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1

Dissection of the insulin signaling pathway via quantitative phosphoproteomics  

PubMed Central

The insulin signaling pathway is of pivotal importance in metabolic diseases, such as diabetes, and in cellular processes, such as aging. Insulin activates a tyrosine phosphorylation cascade that branches to create a complex network affecting multiple biological processes. To understand the full spectrum of the tyrosine phosphorylation cascade, we have defined the tyrosine-phosphoproteome of the insulin signaling pathway, using high resolution mass spectrometry in combination with phosphotyrosine immunoprecipitation and stable isotope labeling by amino acids in cell culture (SILAC) in differentiated brown adipocytes. Of 40 identified insulin-induced effectors, 7 have not previously been described in insulin signaling, including SDR, PKC? binding protein, LRP-6, and PISP/PDZK11, a potential calcium ATPase binding protein. A proteomic interaction screen with PISP/PDZK11 identified the calcium transporting ATPase SERCA2, supporting a connection to calcium signaling. The combination of quantitative phosphoproteomics with cell culture models provides a powerful strategy to dissect the insulin signaling pathways in intact cells.

Kruger, Marcus; Kratchmarova, Irina; Blagoev, Blagoy; Tseng, Yu-Hua; Kahn, C. Ronald; Mann, Matthias

2008-01-01

2

Quantitative phospho-proteomics based on soluble nanopolymers.  

PubMed

Phospho-proteomics, the global analysis of protein phosphorylation, holds great promise for the discovery of cell signaling events that link changes in dynamics of protein phosphorylation to the progression of various diseases, particularly cancer and diabetes. Mass spectrometry has become a powerful tool for identification and global profiling of protein phosphorylation. However, even with continuously improving sensitivity of mass spectrometers, sub-stoichiometric nature of phosphorylation poses enormous challenges for phosphoprotein identification and, particularly, mapping phosphosites. Therefore, a successful mass spectrometry-based phospho-proteomic experiment depends largely on an effective method of phosphopeptide enrichment.We present in this chapter two robust methods based on soluble nanopolymers functionalized for phosphopeptide enrichment. The first method describes the formation of reversible phosphoramidate bonds between amines on the nanopolymer and phosphate groups on peptides, thus enabling selective isolation of phosphopeptides using a molecule size-based filtering device. The second technique is based on the selective chelation of phosphopeptides to zirconia or titania functionalized nanopolymer, which can be isolated from the complex peptide mixture by binding the nanopolymer to solid-phase support through efficient hydrazide chemistry. Combined with stable isotope labeling approaches, both strategies provide reproducible and efficient meanings for quantitative phospho-proteomics. PMID:19241010

Iliuk, Anton; Tao, W Andy

2009-01-01

3

Optimization of peptide density on microarray surface for quantitative phosphoproteomics.  

PubMed

Procedures to determine the density of peptides immobilized on a glass surface for the quantitative detection of phosphorylated peptides for phosphoproteomic applications of peptide microarrays are described. Two kinds of representative fluorescent probe molecules, anti-phosphotyrosine antibody (AB) and phos-tag (PT), were examined to compare their ability for the quantitative detection of phosphorylated peptides. PT is a metal complex with a binding specificity to phosphorylated amino acids, and is much smaller in size than AB. Thus, PT is quantitatively bound to the phosphorylated peptides, even at a high immobilization density without steric hindrance, making them highly suited for future microarrays requiring smaller sized peptide spots for much higher throughput. PMID:21233554

Shimomura, Takashi; Han, Xiaoming; Hata, Akito; Niidome, Takuro; Mori, Takeshi; Katayama, Yoshiki

2011-01-01

4

Quantitative Phosphoproteomics of CXCL12 (SDF-1) Signaling  

PubMed Central

CXCL12 (SDF-1) is a chemokine that binds to and signals through the seven transmembrane receptor CXCR4. The CXCL12/CXCR4 signaling axis has been implicated in both cancer metastases and human immunodeficiency virus type 1 (HIV-1) infection and a more complete understanding of CXCL12/CXCR4 signaling pathways may support efforts to develop therapeutics for these diseases. Mass spectrometry-based phosphoproteomics has emerged as an important tool in studying signaling networks in an unbiased fashion. We employed stable isotope labeling with amino acids in cell culture (SILAC) quantitative phosphoproteomics to examine the CXCL12/CXCR4 signaling axis in the human lymphoblastic CEM cell line. We quantified 4,074 unique SILAC pairs from 1,673 proteins and 89 phosphopeptides were deemed CXCL12-responsive in biological replicates. Several well established CXCL12-responsive phosphosites such as AKT (pS473) and ERK2 (pY204) were confirmed in our study. We also validated two novel CXCL12-responsive phosphosites, stathmin (pS16) and AKT1S1 (pT246) by Western blot. Pathway analysis and comparisons with other phosphoproteomic datasets revealed that genes from CXCL12-responsive phosphosites are enriched for cellular pathways such as T cell activation, epidermal growth factor and mammalian target of rapamycin (mTOR) signaling, pathways which have previously been linked to CXCL12/CXCR4 signaling. Several of the novel CXCL12-responsive phosphoproteins from our study have also been implicated with cellular migration and HIV-1 infection, thus providing an attractive list of potential targets for the development of cancer metastasis and HIV-1 therapeutics and for furthering our understanding of chemokine signaling regulation by reversible phosphorylation.

Wojcechowskyj, Jason A.; Lee, Jessica Y.; Seeholzer, Steven H.; Doms, Robert W.

2011-01-01

5

Quantitative Phosphoproteomics of Proteasome Inhibition in Multiple Myeloma Cells  

PubMed Central

Background The proteasome inhibitor bortezomib represents an important advance in the treatment of multiple myeloma (MM). Bortezomib inhibits the activity of the 26S proteasome and induces cell death in a variety of tumor cells; however, the mechanism of cytotoxicity is not well understood. Methodology/Principal Findings We investigated the differential phosphoproteome upon proteasome inhibition by using stable isotope labeling by amino acids in cell culture (SILAC) in combination with phosphoprotein enrichment and LC-MS/MS analysis. In total 233 phosphoproteins were identified and 72 phosphoproteins showed a 1.5-fold or greater change upon bortezomib treatment. The phosphoproteins with expression alterations encompass all major protein classes, including a large number of nucleic acid binding proteins. Site-specific phosphopeptide quantitation revealed that Ser38 phosphorylation on stathmin increased upon bortezomib treatment, suggesting new mechanisms associated to bortezomib-induced apoptosis in MM cells. Further studies demonstrated that stathmin phosphorylation profile was modified in response to bortezomib treatment and the regulation of stathmin by phosphorylation at specific Ser/Thr residues participated in the cellular response induced by bortezomib. Conclusions/Significance Our systematic profiling of phosphorylation changes in response to bortezomib treatment not only advanced the global mechanistic understanding of the action of bortezomib on myeloma cells but also identified previously uncharacterized signaling proteins in myeloma cells.

Bi, Li-Jun; Tao, Sheng-Ce; Xiong, Sheng; Yin, Xin-Feng; Li, Li-Ping; Lu, Chun-Hua; Jia, Hai-Tao; He, Qing-Yu

2010-01-01

6

Quantitative phosphoproteome profiling of iron-deficient Arabidopsis roots.  

PubMed

Iron (Fe) is an essential mineral nutrient for plants, but often it is not available in sufficient quantities to sustain optimal growth. To gain insights into adaptive processes to low Fe availability at the posttranslational level, we conducted a quantitative analysis of Fe deficiency-induced changes in the phosphoproteome profile of Arabidopsis (Arabidopsis thaliana) roots. Isobaric tags for relative and absolute quantitation-labeled phosphopeptides were analyzed by liquid chromatography-tandem mass spectrometry on an LTQ-Orbitrap with collision-induced dissociation and high-energy collision dissociation capabilities. Using a combination of titanium dioxide and immobilized metal affinity chromatography to enrich phosphopeptides, we extracted 849 uniquely identified phosphopeptides corresponding to 425 proteins and identified several not previously described phosphorylation motifs. A subset of 45 phosphoproteins was defined as being significantly changed in abundance upon Fe deficiency. Kinase motifs in Fe-responsive proteins matched to protein kinase A/calcium calmodulin-dependent kinase II, casein kinase II, and proline-directed kinase, indicating a possible critical function of these kinase classes in Fe homeostasis. To validate our analysis, we conducted site-directed mutagenesis on IAA-CONJUGATE-RESISTANT4 (IAR4), a protein putatively functioning in auxin homeostasis. iar4 mutants showed compromised root hair formation and developed shorter primary roots. Changing serine-296 in IAR4 to alanine resulted in a phenotype intermediate between mutant and wild type, whereas acidic substitution to aspartate to mimic phosphorylation was either lethal or caused an extreme dwarf phenotype, supporting the critical importance of this residue in Fe homeostasis. Our analyses further disclose substantial changes in the abundance of phosphoproteins involved in primary carbohydrate metabolism upon Fe deficiency, complementing the picture derived from previous proteomic and transcriptomic profiling studies. PMID:22438062

Lan, Ping; Li, Wenfeng; Wen, Tuan-Nan; Schmidt, Wolfgang

2012-03-21

7

Quantitative phosphoproteomic analysis of prion-infected neuronal cells  

Microsoft Academic Search

Prion diseases or transmissible spongiform encephalopathies (TSEs) are fatal diseases associated with the conversion of the cellular prion protein (PrPC) to the abnormal prion protein (PrPSc). Since the molecular mechanisms in pathogenesis are widely unclear, we analyzed the global phospho-proteome and detected a differential pattern of tyrosine- and threonine phosphorylated proteins in PrPSc-replicating and pentosan polysulfate (PPS)-rescued N2a cells in

Wibke Wagner; Paul Ajuh; Johannes Löwer; Silja Wessler

2010-01-01

8

P189-T IMAC Enrichment of Phosphopeptides Coupled with 18O Labeling: Quantitative Phosphoproteomics  

PubMed Central

The up- and down-regulation of protein expression has long been a focus of proteomics researchers and has given rise to several mass spectrometry–based quantitation techniques. In the past decade, a great deal of attention has turned toward the subproteomes, particularly those representing post-translational modifications (PTMs), such as phosphorylation. Those PTMs often play key roles in signaling cascades, and affect a number of cellular processes; their study offers insight into intracellular function. We illustrate here phosphoproteome quantitation through the pairing of immobilized metal-affinity chromatography (IMAC) and 18O labeling, which allows for the determination of modulated phosphorylated species in response to external stressors. Following application of varying biological stressors and isolation of each resultant proteome, the samples were proteolytically cleaved using immobilized trypsin. IMAC enrichment of phosphorylated peptides was accomplished using a nitrilotriacetic acid (NTA) analog bonded to silica, presenting Ga3+ as the chelated metal species. Immobilized trypsin was also employed for incorporation of 18O into the sample for quantitative global labeling. It was determined that IMAC enrichment utilizing this combination of chelate, substrate, and metal provided significant enrichment of phosphopeptides that afforded signal levels, which allowed for quantitative analysis of the phosphoproteome. The use of 18O labeling of the samples permitted a global approach to targeting the phosphoproteome concurrent with the non-phosphorylated component. Using MS analysis before and after IMAC-based phosphopeptide enrichment revealed a distinction in regulation of expression and modulation through phosphorylation of the proteins. The coupling of phosphopeptide enrichment with global isotopic labeling provides a valuable and enabling resource for the vastly under-explored area of quantitative phosphoproteomics.

Turner, J. L.; Walters, J. J.; Heutel, J. D.; Radwanski, B. K.; Boland, J.; Ray, K.; Dapron, J. G.

2007-01-01

9

Quantitative phosphoproteomics: New technologies and applications in the DNA damage response.  

PubMed

Cells are highly responsive to their environment. One of the main strategies used by cells in signal transduction is protein phosphorylation, a reversible modification that regulates numerous biological processes. Misregulation of phosphorylation-mediated processes is often implicated in many human diseases and cancers. A global and quantitative analysis of protein phosphorylation provides a powerful new approach and has the potential to reveal new insights in signaling pathways. Recent technological advances in high resolution mass spectrometers and multidimensional liquid chromatography, combined with the use of stable isotope labeling of proteins, have led to the application of quantitative phosphoproteomics to study in vivo signal transduction events on a proteome-wide scale. Here we review recent advancements in quantitative phosphoproteomic technologies, discuss their potentials and identify areas for future development. A key objective of proteomic technology is its application to addressing biological questions. We will therefore describe how current quantitative phosphoproteomic technology can be used to study the molecular basis of phosphorylation events in the DNA damage response. PMID:20855976

Zhou, Huilin; Albuquerque, Claudio P; Liang, Jason; Suhandynata, Raymond T; Weng, Stephanie

2010-09-26

10

Cost-effective isobaric tagging for quantitative phosphoproteomics using DiART reagents.  

PubMed

We describe the use of an isobaric tagging reagent, Deuterium isobaric Amine Reactive Tag (DiART), for quantitative phosphoproteomic experiments. Using DiART tagged custom mixtures of two phosphorylated peptides from alpha casein and their non-phosphorylated counterparts, we demonstrate the compatibility of DiART with TiO2 affinity purification of phosphorylated peptides. Comparison of theoretical vs. experimental reporter ion ratios reveals accurate quantification of phosphorylated peptides over a dynamic range of more than 15-fold. Using DiART labelling and TiO2 enrichment (DiART-TiO2) with large quantities of proteins (8 mg) from the cell lysate of model fungus Aspergillus nidulans, we quantified 744 unique phosphopeptides. Overlap of median values of TiO2 enriched phosphopeptides with theoretical values indicates accurate trends. Altogether these findings confirm the feasibility of performing quantitative phosphoproteomic experiments in a cost-effective manner using isobaric tagging reagents, DiART. PMID:24129742

Ramsubramaniam, Nikhil; Tao, Feng; Li, Shuwei; Marten, Mark R

2013-10-16

11

Quantitative Phospho-proteomics to Investigate the Polo-like Kinase 1-Dependent Phospho-proteome*  

PubMed Central

Polo-like kinase 1 (PLK1) is a key regulator of mitotic progression and cell division, and small molecule inhibitors of PLK1 are undergoing clinical trials to evaluate their utility in cancer therapy. Despite this importance, current knowledge about the identity of PLK1 substrates is limited. Here we present the results of a proteome-wide analysis of PLK1-regulated phosphorylation sites in mitotic human cells. We compared phosphorylation sites in HeLa cells that were or were not treated with the PLK1-inhibitor BI 4834, by labeling peptides via methyl esterification, fractionation of peptides by strong cation exchange chromatography, and phosphopeptide enrichment via immobilized metal affinity chromatography. Analysis by quantitative mass spectrometry identified 4070 unique mitotic phosphorylation sites on 2069 proteins. Of these, 401 proteins contained one or multiple phosphorylation sites whose abundance was decreased by PLK1 inhibition. These include proteins implicated in PLK1-regulated processes such as DNA damage, mitotic spindle formation, spindle assembly checkpoint signaling, and chromosome segregation, but also numerous proteins that were not suspected to be regulated by PLK1. Analysis of amino acid sequence motifs among phosphorylation sites down-regulated under PLK1 inhibition in this data set identified two potential novel variants of the PLK1 consensus motif.

Grosstessner-Hain, Karin; Hegemann, Bjorn; Novatchkova, Maria; Rameseder, Jonathan; Joughin, Brian A.; Hudecz, Otto; Roitinger, Elisabeth; Pichler, Peter; Kraut, Norbert; Yaffe, Michael B.; Peters, Jan-Michael; Mechtler, Karl

2011-01-01

12

Quantitative Phosphoproteomics Identifies Substrates and Functional Modules of Aurora and Polo-Like Kinase Activities in Mitotic Cells  

PubMed Central

Mitosis is a process involving a complex series of events that require careful coordination. Protein phosphorylation by a small number of kinases, in particular Aurora A, Aurora B, the cyclin-dependent kinase–cyclin complex Cdk1/cyclinB, and Polo-like kinase 1 (Plk1), orchestrates almost every step of cell division, from entry into mitosis to cytokinesis. To discover more about the functions of Aurora A, Aurora B, and kinases of the Plk family, we mapped mitotic phosphorylation sites to these kinases through the combined use of quantitative phosphoproteomics and selective targeting of kinase activities by small-molecule inhibitors. Using this integrated approach, we connected 778 phosphorylation sites on 562 proteins with these enzymes in cells arrested in mitosis. By connecting the kinases to protein complexes, we associated these kinases with functional modules. In addition to predicting previously unknown functions, this work establishes additional substrate-recognition motifs for these kinases and provides an analytical template for further use in dissecting kinase signaling events in other areas of cellular signaling and systems biology.

Kettenbach, Arminja N.; Schweppe, Devin K.; Faherty, Brendan K.; Pechenick, Dov; Pletnev, Alexandre A.; Gerber, Scott A.

2013-01-01

13

Quantitative phosphoproteomics identifies substrates and functional modules of Aurora and Polo-like kinase activities in mitotic cells.  

PubMed

Mitosis is a process involving a complex series of events that require careful coordination. Protein phosphorylation by a small number of kinases, in particular Aurora A, Aurora B, the cyclin-dependent kinase-cyclin complex Cdk1/cyclinB, and Polo-like kinase 1 (Plk1), orchestrates almost every step of cell division, from entry into mitosis to cytokinesis. To discover more about the functions of Aurora A, Aurora B, and kinases of the Plk family, we mapped mitotic phosphorylation sites to these kinases through the combined use of quantitative phosphoproteomics and selective targeting of kinase activities by small-molecule inhibitors. Using this integrated approach, we connected 778 phosphorylation sites on 562 proteins with these enzymes in cells arrested in mitosis. By connecting the kinases to protein complexes, we associated these kinases with functional modules. In addition to predicting previously unknown functions, this work establishes additional substrate-recognition motifs for these kinases and provides an analytical template for further use in dissecting kinase signaling events in other areas of cellular signaling and systems biology. PMID:21712546

Kettenbach, Arminja N; Schweppe, Devin K; Faherty, Brendan K; Pechenick, Dov; Pletnev, Alexandre A; Gerber, Scott A

2011-06-28

14

Quantitative phospho-proteomics of early elicitor signalling in Arabidopsis  

Microsoft Academic Search

Perception of general elicitors by plant cells initiates signal\\u000atransduction cascades that are regulated by protein\\u000aphosphorylation. The earliest signaling events occur\\u000awithin minutes and include ion fluxes across the plasma\\u000amembrane, activation of MAPKs, and the formation of\\u000areactive oxygen species. The phosphorylation events that\\u000aregulate these signaling cascades are largely unknown.\\u000aHere we present a mass spectrometry-based quantitative

Joris J. Benschop; Shabaz Mohammed; Martina O'Flaherty; Albert J. R. Heck; Monique Slijper; Frank L. H. Menke

2007-01-01

15

Glycoprotein Capture and Quantitative Phosphoproteomics Indicate Coordinated Regulation of Cell Migration upon Lysophosphatidic Acid Stimulation*  

PubMed Central

The lipid mediator lysophosphatidic acid (LPA) is a serum component that regulates cellular functions such as proliferation, migration, and survival via specific G protein-coupled receptors. The underlying signaling mechanisms are still incompletely understood, including those that operate at the plasma membrane to modulate cell-cell and cell-matrix interactions in LPA-promoted cell migration. To explore LPA-evoked phosphoregulation with a focus on cell surface proteins, we combined glycoproteome enrichment by immobilized lectins with SILAC-based quantitative phosphoproteomics. We performed biological replicate analyses in SCC-9 squamous cell carcinoma cells and repeatedly quantified the effect of 1.5- and 5-min LPA treatment on more than 700 distinct phosphorylations in lectin-purified proteins. We detected many regulated phosphorylation events on various types of plasma membrane proteins such as cell adhesion molecules constituting adherens junctions, desmosomes, and hemidesmosomes. Several of these LPA-regulated phosphorylation sites have been characterized in a biological context other than G protein-coupled receptor signaling, and the transfer of this functional information suggests coordinated and multifactorial cell adhesion control in LPA-induced cell migration. Additionally, we identified LPA-mediated activation loop phosphorylation of the serine/threonine kinase Wnk1 and verified a role of Wnk1 for LPA-induced cell migration in knock-down experiments. In conclusion, the glycoproteome phosphoproteomics strategy described here sheds light on incompletely understood mechanisms in LPA-induced cell migratory behavior.

Mausbacher, Nina; Schreiber, Thiemo B.; Daub, Henrik

2010-01-01

16

A quantitative map of the liver mitochondrial phosphoproteome reveals posttranslational control of ketogenesis.  

PubMed

Mitochondria are dynamic organelles that play a central role in a diverse array of metabolic processes. Elucidating mitochondrial adaptations to changing metabolic demands and the pathogenic alterations that underlie metabolic disorders represent principal challenges in cell biology. Here, we performed multiplexed quantitative mass spectrometry-based proteomics to chart the remodeling of the mouse liver mitochondrial proteome and phosphoproteome during both acute and chronic physiological transformations in more than 50 mice. Our analyses reveal that reversible phosphorylation is widespread in mitochondria, and is a key mechanism for regulating ketogenesis during the onset of obesity and type 2 diabetes. Specifically, we have demonstrated that phosphorylation of a conserved serine on Hmgcs2 (S456) significantly enhances its catalytic activity in response to increased ketogenic demand. Collectively, our work describes the plasticity of this organelle at high resolution and provides a framework for investigating the roles of proteome restructuring and reversible phosphorylation in mitochondrial adaptation. PMID:23140645

Grimsrud, Paul A; Carson, Joshua J; Hebert, Alex S; Hubler, Shane L; Niemi, Natalie M; Bailey, Derek J; Jochem, Adam; Stapleton, Donald S; Keller, Mark P; Westphall, Michael S; Yandell, Brian S; Attie, Alan D; Coon, Joshua J; Pagliarini, David J

2012-11-01

17

Quantitative phosphoproteomics analysis reveals broad regulatory role of heparan sulfate on endothelial signaling.  

PubMed

Heparan sulfate (HS) is a linear, abundant, highly sulfated polysaccharide that expresses in the vasculature. Recent genetic studies documented that HS critically modulates various endothelial cell functions. However, elucidation of the underlying molecular mechanism has been challenging because of the presence of a large number of HS-binding ligands found in the examined experimental conditions. In this report, we used quantitative phosphoproteomics to examine the global HS-dependent signaling by comparing wild type and HS-deficient endothelial cells that were cultured in a serum-containing medium. A total of 7222 phosphopeptides, corresponding to 1179 proteins, were identified. Functional correlation analysis identified 25 HS-dependent functional networks, and the top five are related to cell morphology, cellular assembly and organization, cellular function and maintenance, cell-to-cell communication, inflammatory response and disorder, cell growth and proliferation, cell movement, and cellular survival and death. This is consistent with cell function studies showing that HS deficiency altered endothelial cell growth and mobility. Mining for the underlying molecular mechanisms further revealed that HS modulates signaling pathways critically related to cell adhesion, migration, and coagulation, including ILK, integrin, actin cytoskeleton organization, tight junction and thrombin signaling. Intriguingly, this analysis unexpectedly determined that the top HS-dependent signaling is the IGF-1 signaling pathway, which has not been known to be modulated by HS. In-depth analysis of growth factor signaling identified 22 HS-dependent growth factor/cytokine/growth hormone signaling pathways, including those both previously known, such as HGF and VEGF, and those unknown, such as IGF-1, erythropoietin, angiopoietin/Tie, IL-17A and growth hormones. Twelve of the identified 22 growth factor/cytokine/growth hormone signaling pathways, including IGF-1 and angiopoietin/Tie signaling, were alternatively confirmed in phospho-receptor tyrosine kinase array analysis. In summary, our SILAC-based quantitative phosphoproteomic analysis confirmed previous findings and also uncovered novel HS-dependent functional networks and signaling, revealing a much broader regulatory role of HS on endothelial signaling. PMID:23649490

Qiu, Hong; Jiang, Jun-Lin; Liu, Miao; Huang, Xin; Ding, Shi-Jian; Wang, Lianchun

2013-05-06

18

Research resource: identification of novel growth hormone-regulated phosphorylation sites by quantitative phosphoproteomics.  

PubMed

GH and GH receptors are expressed throughout life, and GH elicits a diverse range of responses, including growth and altered metabolism. It is therefore important to understand the full spectrum of GH signaling pathways and cellular responses. We applied mass spectrometry-based phosphoproteomics combined with stable isotope labeling with amino acids in cell culture to identify proteins rapidly phosphorylated in response to GH in 3T3-F442A preadipocytes. We identified 132 phosphosites in 95 proteins that exhibited rapid (5 or 15 min) GH-dependent statistically significant increases in phosphorylation by more than or equal to 50% and 96 phosphosites in 46 proteins that were down-regulated by GH by more than or equal to 30%. Several of the GH-stimulated phosphorylation sites were known (e.g. regulatory Thr/Tyr in Erks 1 and 2, Tyr in signal transducers and activators of transcription (Stat) 5a and 5b, Ser939 in tuberous sclerosis protein (TSC) 2 or tuberin). The remaining 126 GH-stimulated sites were not previously associated with GH. Kyoto Encyclopedia of Genes and Genomes pathway analysis of GH-stimulated sites indicated enrichment in proteins associated with the insulin and mammalian target of rapamycin (mTOR) pathways, regulation of the actin cytoskeleton, and focal adhesions. Akt/protein kinase A consensus sites (RXRXXS/T) were the most commonly phosphorylated consensus sites. Immunoblotting confirmed GH-stimulated phosphorylation of all seven novel GH-dependent sites tested [regulatory sites in proline-rich Akt substrate, 40 kDA (PRAS40), regulatory associated protein of mTOR, ATP-citrate lyase, Na(+)/H(+) exchanger-1, N-myc downstream regulated gene 1, and Shc]). The immunoblot results suggest that many, if not most, of the GH-stimulated phosphosites identified in this large-scale quantitative phosphoproteomics analysis, including sites in multiple proteins in the Akt/ mTOR complex 1 pathway, are phosphorylated in response to GH. Their identification significantly broadens our thinking of GH-regulated cell functions. PMID:22570334

Ray, Bridgette N; Kweon, Hye Kyong; Argetsinger, Lawrence S; Fingar, Diane C; Andrews, Philip C; Carter-Su, Christin

2012-05-08

19

Quantitative phosphoproteomics identifies filaggrin and other targets of ionizing radiation in a human skin model  

PubMed Central

Our objective here was to perform a quantitative phosphoproteomic study on a reconstituted human skin tissue to identify low and high dose ionizing radiation dependent signaling in a complex 3-dimensional setting. Application of an isobaric labeling strategy using sham and 3 radiation doses (3, 10, 200 cGy) resulted in the identification of 1052 unique phosphopeptides. Statistical analyses identified 176 phosphopeptides showing significant changes in response to radiation and radiation dose. Proteins responsible for maintaining skin structural integrity including keratins and desmosomal proteins (desmoglein, desmoplakin, plakophilin 1, 2 and 3) had altered phosphorylation levels following exposure to both low and high doses of radiation. Altered phosphorylation of multiple sites in profilaggrin linker domains coincided with altered profilaggrin processing suggesting a role for linker phosphorylation in human profilaggrin regulation. These studies demonstrate that the reconstituted human skin system undergoes a coordinated response to both low and high doses of ionizing radiation involving multiple layers of the stratified epithelium that serve to maintain tissue integrity and mitigate effects of radiation exposure.

Yang, Feng; Waters, Katrina M; Webb-Robertson, Bobbie-Jo; Sowa, Marianne B.; von Neubeck, Claire; Aldrich, Josh T.; Markillie, L. Meng; Wirgau, Rachel M.; Gritsenko, Marina A.; Zhao, Rui; Camp, David G.; Smith, Richard D.; Stenoien, David L.

2012-01-01

20

Automated, reproducible, titania-based phosphopeptide enrichment strategy for label-free quantitative phosphoproteomics.  

PubMed

An automated phosphopeptide enrichment strategy is described using titanium dioxide (TiO2)-packed, fused silica capillaries for use with liquid chromatography (LC)-mass spectrometry (MS)/MS-based, label-free proteomics workflows. To correlate an optimum peptide:TiO2 loading ratio between different particle types, the ratio of phenyl phosphate-binding capacities was used. The optimum loading for the column was then verified through replicate enrichments of a range of quantities of digested rat brain tissue cell lysate. Fractions were taken during sample loading, multiple wash steps, and the elution steps and analyzed by LC-MS/MS to gauge the efficiency and reproducibility of the enrichment. Greater than 96% of the total phosphopeptides were detected in the elution fractions, indicating efficient trapping of the phosphopeptides on the first pass of enrichment. The quantitative reproducibility of the automated setup was also improved greatly with phosphopeptide intensities from replicate enrichments exhibiting a median coefficient of variation (CV) of 5.8%, and 80% of the identified phosphopeptides had CVs below 11.1%, while maintaining >85% specificity. By providing this high degree of analytical reproducibility, this method allows for label-free phosphoproteomics over large sample sets with complex experimental designs (multiple biological conditions, multiple biological replicates, multiple time-points, etc.), including large-scale clinical cohorts. PMID:23542237

Richardson, Brenna McJury; Soderblom, Erik J; Thompson, J Will; Moseley, M Arthur

2013-04-01

21

Quantitative phosphoproteomics using acetone-based Peptide labeling: method evaluation and application to a cardiac ischemia/reperfusion model.  

PubMed

Mass spectrometry (MS) techniques to globally profile protein phosphorylation in cellular systems that are relevant to physiological or pathological changes have been of significant interest in biological research. An MS-based strategy utilizing an inexpensive acetone-based peptide-labeling technique known as reductive alkylation by acetone (RABA) for quantitative phosphoproteomics was explored to evaluate its capacity. Because the chemistry for RABA labeling for phosphorylation profiling had not been previously reported, it was first validated using a standard phosphoprotein and identical phosphoproteomes from cardiac tissue extracts. A workflow was then utilized to compare cardiac tissue phosphoproteomes from mouse hearts not expressing FGF2 versus hearts expressing low-molecular-weight fibroblast growth factor-2 (LMW FGF2) to relate low-molecular-weight fibroblast growth factor-2 (LMW FGF2)-mediated cardioprotective phenomena induced by ischemia/reperfusion injury of hearts, with downstream phosphorylation changes in LMW FGF2 signaling cascades. Statistically significant phosphorylation changes were identified at 14 different sites on 10 distinct proteins, including some with mechanisms already established for LMW FGF2-mediated cardioprotective signaling (e.g., connexin-43), some with new details linking LMW FGF2 to the cardioprotective mechanisms (e.g., cardiac myosin binding protein C or cMyBPC), and also several new downstream effectors not previously recognized for cardio-protective signaling by LMW FGF2. Additionally, one of the phosphopeptides, cMyBPC/pSer-282, identified was further verified with site-specific quantification using an SRM (selected reaction monitoring)-based approach that also relies on isotope labeling of a synthetic phosphopeptide with deuterated acetone as an internal standard. Overall, this study confirms that the inexpensive acetone-based peptide labeling can be used in both exploratory and targeted quantification phosphoproteomic studies to identify and verify biologically relevant phosphorylation changes in whole tissues. PMID:24016359

Wijeratne, Aruna B; Manning, Janet R; Schultz, Jo El J; Greis, Kenneth D

2013-09-24

22

Quantitative Phosphoproteome Profiling of Iron-Deficient Arabidopsis Roots1[C][W  

PubMed Central

Iron (Fe) is an essential mineral nutrient for plants, but often it is not available in sufficient quantities to sustain optimal growth. To gain insights into adaptive processes to low Fe availability at the posttranslational level, we conducted a quantitative analysis of Fe deficiency-induced changes in the phosphoproteome profile of Arabidopsis (Arabidopsis thaliana) roots. Isobaric tags for relative and absolute quantitation-labeled phosphopeptides were analyzed by liquid chromatography-tandem mass spectrometry on an LTQ-Orbitrap with collision-induced dissociation and high-energy collision dissociation capabilities. Using a combination of titanium dioxide and immobilized metal affinity chromatography to enrich phosphopeptides, we extracted 849 uniquely identified phosphopeptides corresponding to 425 proteins and identified several not previously described phosphorylation motifs. A subset of 45 phosphoproteins was defined as being significantly changed in abundance upon Fe deficiency. Kinase motifs in Fe-responsive proteins matched to protein kinase A/calcium calmodulin-dependent kinase II, casein kinase II, and proline-directed kinase, indicating a possible critical function of these kinase classes in Fe homeostasis. To validate our analysis, we conducted site-directed mutagenesis on IAA-CONJUGATE-RESISTANT4 (IAR4), a protein putatively functioning in auxin homeostasis. iar4 mutants showed compromised root hair formation and developed shorter primary roots. Changing serine-296 in IAR4 to alanine resulted in a phenotype intermediate between mutant and wild type, whereas acidic substitution to aspartate to mimic phosphorylation was either lethal or caused an extreme dwarf phenotype, supporting the critical importance of this residue in Fe homeostasis. Our analyses further disclose substantial changes in the abundance of phosphoproteins involved in primary carbohydrate metabolism upon Fe deficiency, complementing the picture derived from previous proteomic and transcriptomic profiling studies.

Lan, Ping; Li, Wenfeng; Wen, Tuan-Nan; Schmidt, Wolfgang

2012-01-01

23

Quantitative phosphoproteomic analysis of neuronal intermediate filament proteins (NF-M/H) in Alzheimer's disease by iTRAQ  

PubMed Central

Aberrant hyperphosphorylation of neuronal cytoskeletal proteins is one of the major pathological hallmarks of neurodegenerative disorders such as Alzheimer disease (AD), amyotrophic lateral sclerosis (ALS), and Parkinson's disease (PD). Human NF-M/H display a large number of multiple KSP repeats in the carboxy-terminal tail domain, which are phosphorylation sites of proline-directed serine/threonine (pSer/Thr-Pro, KS/T-P) kinases. The phosphorylation sites of NF-M/H have not been characterized in AD brain. Here, we use quantitative phosphoproteomic methodology, isobaric tag for relative and absolute quantitation (iTRAQ), for the characterization of NF-M/H phosphorylation sites in AD brain. We identified 13 hyperphosphorylated sites of NF-M; 9 Lys-Ser-Pro (KSP) sites; 2 variant motifs, Glu-Ser-Pro (ESP) Ser-736 and Leu-Ser-Pro (LSP) Ser-837; and 2 non-S/T-P motifs, Ser-783 and Ser-788. All the Ser/Thr residues are phosphorylated at significantly greater abundance in AD brain compared with control brain. Ten hyperphosphorylated KSP sites have been identified on the C-terminal tail domain of NF-H, with greater abundance of phosphorylation in AD brain compared with control brain. Our data provide the direct evidence that NF-M/H are hyperphosphorylated in AD compared with control brain and suggest the role of both proline-directed and non-proline-directed protein kinases in AD. This study represents the first comprehensive iTRAQ analyses and quantification of phosphorylation sites of human NF-M and NF-H from AD brain and suggests that aberrant hyperphosphorylation of neuronal intermediate filament proteins is involved in AD.—Rudrabhatla, P., Grant, P., Jaffe, H., Strong, M. J., Pant, H. C. Quantitative phosphoproteomic analysis of neuronal intermediate filament proteins (NF-M/H) in Alzheimer's disease by iTRAQ.

Rudrabhatla,*, Parvathi; Grant,*, Philip; Jaffe, Howard; Strong, Michael J.; Pant, Harish C.

2010-01-01

24

Quantitative phosphoproteomic analysis of soybean root hairs inoculated with Bradyrhizobium japonicum.  

PubMed

Root hairs are single hair-forming cells on roots that function to increase root surface area, enhancing water and nutrient uptake. In leguminous plants, root hairs also play a critical role as the site of infection by symbiotic nitrogen fixing rhizobia, leading to the formation of a novel organ, the nodule. The initial steps in the rhizobia-root hair infection process are known to involve specific receptor kinases and subsequent kinase cascades. Here, we characterize the phosphoproteome of the root hairs and the corresponding stripped roots (i.e. roots from which root hairs were removed) during rhizobial colonization and infection to gain insight into the molecular mechanism of root hair cell biology. We chose soybean (Glycine max L.), one of the most important crop plants in the legume family, for this study because of its larger root size, which permits isolation of sufficient root hair material for phosphoproteomic analysis. Phosphopeptides derived from root hairs and stripped roots, mock inoculated or inoculated with the soybean-specific rhizobium Bradyrhizobium japonicum, were labeled with the isobaric tag eight-plex iTRAQ, enriched using Ni-NTA magnetic beads and subjected to nanoRPLC-MS/MS1 analysis using HCD and decision tree guided CID/ETD strategy. A total of 1625 unique phosphopeptides, spanning 1659 nonredundant phosphorylation sites, were detected from 1126 soybean phosphoproteins. Among them, 273 phosphopeptides corresponding to 240 phosphoproteins were found to be significantly regulated (>1.5-fold abundance change) in response to inoculation with B. japonicum. The data reveal unique features of the soybean root hair phosphoproteome, including root hair and stripped root-specific phosphorylation suggesting a complex network of kinase-substrate and phosphatase-substrate interactions in response to rhizobial inoculation. PMID:22843990

Nguyen, Tran Hong Nha; Brechenmacher, Laurent; Aldrich, Joshua T; Clauss, Therese R; Gritsenko, Marina A; Hixson, Kim K; Libault, Marc; Tanaka, Kiwamu; Yang, Feng; Yao, Qiuming; Pasa-Toli?, Ljiljana; Xu, Dong; Nguyen, Henry T; Stacey, Gary

2012-07-25

25

Quantitative phosphoproteomics of transforming growth factor-? signaling in colon cancer cells.  

PubMed

The transforming growth factor-? (TGF-?) signaling pathway progresses through a series of protein phosphorylation regulated steps. Smad4 is a key mediator of the classical TGF-? signaling pathway; however, reports suggest that TGF-? can activate other cellular pathways independent of Smad4. By investigating the TGF-?-regulated phosphoproteome, we aimed to uncover new functions controlled by TGF-?. We applied titanium dioxide to enrich phosphopeptides from stable isotope labeling with amino acids in cell culture (SILAC)-labeled SW480 cells stably expressing Smad4 and profiled them by mass spectrometry. TGF-? stimulation for 30?min resulted in the induction of 17 phosphopeptides and the repression of 8 from a total of 149 unique phosphopeptides. Proteins previously not known to be phosphorylated by TGF-? including programmed cell death protein 4, nuclear ubiquitous casein and cyclin-dependent kinases substrate, hepatoma-derived growth factor and cell division kinases amongst others were induced following TGF-? stimulation, while the phosphorylation of TRAF2 and NCK-interacting protein kinase are examples of proteins whose phosphorylation status was repressed. This phosphoproteomic screen has identified new TGF-?-modulated phosphorylation responses in colon carcinoma cells. PMID:21751366

Ali, Naveid A; Molloy, Mark P

2011-08-01

26

Quantitative phosphoproteomics in nuclei of vasopressin-sensitive renal collecting duct cells.  

PubMed

Vasopressin regulates transport across the collecting duct epithelium in part via effects on gene transcription. Transcriptional regulation occurs partially via changes in phosphorylation of transcription factors, transcriptional coactivators, and protein kinases in the nucleus. To test whether vasopressin alters the nuclear phosphoproteome of vasopressin-sensitive cultured mouse mpkCCD cells, we used stable isotope labeling and mass spectrometry to quantify thousands of phosphorylation sites in nuclear extracts and nuclear pellet fractions. Measurements were made in the presence and absence of the vasopressin analog dDAVP. Of the 1,251 sites quantified, 39 changed significantly in response to dDAVP. Network analysis of the regulated proteins revealed two major clusters ("cell-cell adhesion" and "transcriptional regulation") that were connected to known elements of the vasopressin signaling pathway. The hub proteins for these two clusters were the transcriptional coactivator ?-catenin and the transcription factor c-Jun. Phosphorylation of ?-catenin at Ser552 was increased by dDAVP [log(2)(dDAVP/vehicle) = 1.79], and phosphorylation of c-Jun at Ser73 was decreased [log(2)(dDAVP/vehicle) = -0.53]. The ?-catenin site is known to be targeted by either protein kinase A or Akt, both of which are activated in response to vasopressin. The c-Jun site is a canonical target for the MAP kinase Jnk2, which is downregulated in response to vasopressin in the collecting duct. The data support the idea that vasopressin-mediated control of transcription in collecting duct cells involves selective changes in the nuclear phosphoproteome. All data are available to users at http://helixweb.nih.gov/ESBL/Database/mNPPD/. PMID:22992673

Bolger, Steven J; Hurtado, Patricia A Gonzales; Hoffert, Jason D; Saeed, Fahad; Pisitkun, Trairak; Knepper, Mark A

2012-09-19

27

Dynamics of the G Protein-coupled Vasopressin V2 Receptor Signaling Network Revealed by Quantitative Phosphoproteomics*  

PubMed Central

G protein-coupled receptors (GPCRs) regulate diverse physiological processes, and many human diseases are due to defects in GPCR signaling. To identify the dynamic response of a signaling network downstream from a prototypical Gs-coupled GPCR, the vasopressin V2 receptor, we have carried out multireplicate, quantitative phosphoproteomics with iTRAQ labeling at four time points following vasopressin exposure at a physiological concentration in cells isolated from rat kidney. A total of 12,167 phosphopeptides were identified from 2,783 proteins, with 273 changing significantly in abundance with vasopressin. Two-dimensional clustering of phosphopeptide time courses and Gene Ontology terms revealed that ligand binding to the V2 receptor affects more than simply the canonical cyclic adenosine monophosphate-protein kinase A and arrestin pathways under physiological conditions. The regulated proteins included key components of actin cytoskeleton remodeling, cell-cell adhesion, mitogen-activated protein kinase signaling, Wnt/?-catenin signaling, and apoptosis pathways. These data suggest that vasopressin can regulate an array of cellular functions well beyond its classical role in regulating water and solute transport. These results greatly expand the current view of GPCR signaling in a physiological context and shed new light on potential roles for this signaling network in disorders such as polycystic kidney disease. Finally, we provide an online resource of physiologically regulated phosphorylation sites with dynamic quantitative data (http://helixweb.nih.gov/ESBL/Database/TiPD/index.html).

Hoffert, Jason D.; Pisitkun, Trairak; Saeed, Fahad; Song, Jae H.; Chou, Chung-Lin; Knepper, Mark A.

2012-01-01

28

Phosphoproteomics in cancer.  

PubMed

Reversible protein phosphorylation serves as a basis for regulating a number of cellular processes. Aberrant activation of kinase signaling pathways is commonly associated with several cancers. Recent developments in phosphoprotein/phosphopeptide enrichment strategies and quantitative mass spectrometry have resulted in robust pipelines for high-throughput characterization of phosphorylation in a global fashion. Today, it is possible to profile site-specific phosphorylation events on thousands of proteins in a single experiment. The potential of this approach is already being realized to characterize signaling pathways that govern oncogenesis. In addition, chemical proteomic strategies have been used to unravel targets of kinase inhibitors, which are otherwise difficult to characterize. This review summarizes various approaches used for analysis of the phosphoproteome in general, and protein kinases in particular, highlighting key cancer phosphoproteomic studies. PMID:20937571

Harsha, H C; Pandey, Akhilesh

2010-09-26

29

Quantitative phosphoproteomic analysis reveals vasopressin V2-receptor-dependent signaling pathways in renal collecting duct cells.  

PubMed

Vasopressin's action in renal cells to regulate water transport depends on protein phosphorylation. Here we used mass spectrometry-based quantitative phosphoproteomics to identify signaling pathways involved in the short-term V2-receptor-mediated response in cultured collecting duct cells (mpkCCD) from mouse. Using Stable Isotope Labeling by Amino acids in Cell culture (SILAC) with two treatment groups (0.1 nM dDAVP or vehicle for 30 min), we carried out quantification of 2884 phosphopeptides. The majority (82%) of quantified phosphopeptides did not change in abundance in response to dDAVP. Analysis of the 273 phosphopeptides increased by dDAVP showed a predominance of so-called "basophilic" motifs consistent with activation of kinases of the AGC family. Increases in phosphorylation of several known protein kinase A targets were found. In addition, increased phosphorylation of targets of the calmodulin-dependent kinase family was seen, including autophosphorylation of calmodulin-dependent kinase 2 at T286. Analysis of the 254 phosphopeptides decreased in abundance by dDAVP showed a predominance of so-called "proline-directed" motifs, consistent with down-regulation of mitogen-activated or cyclin-dependent kinases. dDAVP decreased phosphorylation of both JNK1/2 (T183/Y185) and ERK1/2 (T183/Y185; T203/Y205), consistent with a decrease in activation of these proline-directed kinases in response to dDAVP. Both ERK and JNK were able to phosphorylate residue S261of aquaporin-2 in vitro, a site showing a decrease in phosphorylation in response to dDAVP in vivo. The data support roles for multiple vasopressin V2-receptor-dependent signaling pathways in the vasopressin signaling network of collecting duct cells, involving several kinases not generally accepted to regulate collecting duct function. PMID:20139300

Rinschen, Markus M; Yu, Ming-Jiun; Wang, Guanghui; Boja, Emily S; Hoffert, Jason D; Pisitkun, Trairak; Knepper, Mark A

2010-02-05

30

A comparative phosphoproteomic analysis of a human tumor metastasis model using a label free quantitative approach  

PubMed Central

Alterations in cellular phosphorylation patterns have been implicated in a number of diseases, including cancer, through multiple mechanisms. Herein we present a survey of the phosphorylation profiles of an isogenic pair of human cancer cell lines with opposite metastatic phenotype. Phosphopeptides were enriched from tumor cell lysates with titanium dioxide and zirconium dioxide, and identified with nano-LC-MS/MS using an automatic cross-validation of MS/MS and MS/MS/MS (MS2 + MS3) data-dependent neutral loss method. A spectral counting quantitative strategy was applied to the two cell line samples on the MS2-only scan which was implemented successively after each MS2 + MS3 scan in the same sample. For all regulated phosphopeptides reported by spectral counting analysis, sequence and phosphorylation site assignments were validated by a MS2 + MS3 data-dependent neutral loss method. With this approach, we identified over 70 phosphorylated sites on 27 phosphoproteins as being differentially expressed with respect to tumor cell phenotype. The altered expression levels of proteins identified by LC-MS/MS were validated using Western blotting. Using network pathway analysis, we observed that the majority of the differentially expressed proteins were highly interconnected and belong to two major intracellular signaling pathways. Our findings suggest that the phosphorylation of isoform A of lamin A/C and GTPase activating protein binding protein 1 is associated with metastatic propensity. The study demonstrates a quantitative and comparative proteomics strategy to identify differential phosphorylation patterns in complex biological samples.

Xie, Xiaolei; Feng, Shun; Vuong, Huy; Liu, Yashu; Goodison, Steve; Lubman, David M

2010-01-01

31

Quantitative phosphoproteomics studies using stable isotope dimethyl labeling coupled with IMAC-HILIC-nanoLC-MS/MS for estrogen-induced transcriptional regulation.  

PubMed

17?-Estradiol (E2) regulates transcriptional activity partly by inducing protein-kinase cascades, leading to the phosphorylation of estrogen receptors (ERs) and other functional proteins. Many of these phosphorylation events are also modulated by growth factors. To gain an insight into E2-modulated protein phosphorylation, we applied quantitative phosphoproteomics to investigate global changes in protein phosphorylation induced by E2 in MCF-7 cells. Proteomic analyses using stable isotope dimethyl labeling coupled with immobilized metal affinity chromatography-hydrophilic interaction liquid chromatography (IMAC-HILIC) fractionation and nanoLC-MS/MS identified and quantified 2857 unique phosphorylation sites in 1338 phosphoproteins from 1 mg of total cellular protein. In addition to S118 of ER?, a 30-min E2 treatment significantly altered the status of 403 phosphorylation sites, including 112 novel sites. Interestingly, the substrate motifs for ERK1/2 were largely enriched in both the up-regulated and down-regulated phosphorylation sites. An increase in the phosphorylation on either the T202 or Y204 sites of ERK1 was observed after E2 treatment, while dual phosphorylation on both sites were not detected, implying that a feedback loop to deactivate MAPK signaling was achieved during a 30-min E2 treatment. In contrast, the PKA and CKII substrate motifs were majorly enriched among the up-regulated phosphorylation sites. Western blot analysis confirmed that E2 increased the phosphorylation level of S226 within a CKII motif of HSP90? by a factor of 2- to 3-fold without changing the total protein expression level. E2 also up-regulated phosphorylations of S255 in HSP90? and S353 within a CKII motif of HSP90?. These results indicated that E2 may modulate gene transcription by affecting the stability, function, and activity of many regulators through a HSP90 phosphorylation-mediated chaperoning process. This study, using a quantitative, multidimensional separation phosphoproteomic approach that required a relatively low amount of cells, provides new insights into the diversity, variability, and dynamic nature of the protein phosphorylation/dephosphorylation elicited by E2. PMID:21210654

Wu, Chin-Jen; Chen, Yen-Wen; Tai, Jung-Hsiang; Chen, Shu-Hui

2011-02-14

32

Quantitative- and Phospho-Proteomic Analysis of the Yeast Response to the Tyrosine Kinase Inhibitor Imatinib to Pharmacoproteomics-Guided Drug Line Extension  

PubMed Central

Abstract Imatinib mesylate (IM) is a potent tyrosine kinase inhibitor used as front-line therapy in chronic myeloid leukemia, a disease caused by the oncogenic kinase Bcr-Abl. Although the clinical success of IM set a new paradigm in molecular-targeted therapy, the emergence of IM resistance is a clinically significant problem. In an effort to obtain new insights into the mechanisms of adaptation and tolerance to IM, as well as the signaling pathways potentially affected by this drug, we performed a two-dimensional electrophoresis-based quantitative- and phospho-proteomic analysis in the eukaryotic model Saccharomyces cerevisiae. We singled out proteins that were either differentially expressed or differentially phosphorylated in response to IM, using the phosphoselective dye Pro-Q® Diamond, and identified 18 proteins in total. Ten were altered only at the content level (mostly decreased), while the remaining 8 possessed IM-repressed phosphorylation. These 18 proteins are mainly involved in cellular carbohydrate processes (glycolysis/gluconeogenesis), translation, protein folding, ion homeostasis, and nucleotide and amino acid metabolism. Remarkably, all 18 proteins have human functional homologs. A role for HSP70 proteins in the response to IM, as well as decreased glycolysis as a metabolic marker of IM action are suggested, consistent with findings from studies in human cell lines. The previously-proposed effect of IM as an inhibitor of vacuolar H+-ATPase function was supported by the identification of an underexpressed protein subunit of this complex. Taken together, these findings reinforce the role of yeast as a valuable eukaryotic model for pharmacological studies and identification of new drug targets, with potential clinical implications in drug reassignment or line extension under a personalized medicine perspective.

dos Santos, Sandra C.; Mira, Nuno P.; Moreira, Ana S.

2012-01-01

33

Quantitative- and phospho-proteomic analysis of the yeast response to the tyrosine kinase inhibitor imatinib to pharmacoproteomics-guided drug line extension.  

PubMed

Imatinib mesylate (IM) is a potent tyrosine kinase inhibitor used as front-line therapy in chronic myeloid leukemia, a disease caused by the oncogenic kinase Bcr-Abl. Although the clinical success of IM set a new paradigm in molecular-targeted therapy, the emergence of IM resistance is a clinically significant problem. In an effort to obtain new insights into the mechanisms of adaptation and tolerance to IM, as well as the signaling pathways potentially affected by this drug, we performed a two-dimensional electrophoresis-based quantitative- and phospho-proteomic analysis in the eukaryotic model Saccharomyces cerevisiae. We singled out proteins that were either differentially expressed or differentially phosphorylated in response to IM, using the phosphoselective dye Pro-Q(®) Diamond, and identified 18 proteins in total. Ten were altered only at the content level (mostly decreased), while the remaining 8 possessed IM-repressed phosphorylation. These 18 proteins are mainly involved in cellular carbohydrate processes (glycolysis/gluconeogenesis), translation, protein folding, ion homeostasis, and nucleotide and amino acid metabolism. Remarkably, all 18 proteins have human functional homologs. A role for HSP70 proteins in the response to IM, as well as decreased glycolysis as a metabolic marker of IM action are suggested, consistent with findings from studies in human cell lines. The previously-proposed effect of IM as an inhibitor of vacuolar H(+)-ATPase function was supported by the identification of an underexpressed protein subunit of this complex. Taken together, these findings reinforce the role of yeast as a valuable eukaryotic model for pharmacological studies and identification of new drug targets, with potential clinical implications in drug reassignment or line extension under a personalized medicine perspective. PMID:22775238

Dos Santos, Sandra C; Mira, Nuno P; Moreira, Ana S; Sá-Correia, Isabel

2012-07-09

34

Quantitative Genetic Dissection of Shoot Architecture Traits in Maize: Towards a Functional Genomics Approach  

Technology Transfer Automated Retrieval System (TEKTRAN)

Quantitative trait loci (QTL) affecting the total number of leaves (TNOL) made prior to flowering and the number of leaves below the ear (NLBE) were mapped and characterized in order to dissect the genetic regulatory components of these agronomically important traits of corn. The full set of interm...

35

Genetic and molecular dissection of quantitative traits in rice  

Microsoft Academic Search

Recent progress in the generation of a molecular genetic map and markers for rice has made possible a new phase of mapping individual genes associated with complex traits. This type of analysis is often referred to as quantitative trait locus (QTL) analysis. Increasing numbers of QTL analyses are providing enormous amounts of information about QTLs, such as the numbers of

Masahiro Yano; Takuji Sasaki

1997-01-01

36

Using Quantitative Redox Proteomics to Dissect the Yeast Redoxome*  

PubMed Central

To understand and eventually predict the effects of changing redox conditions and oxidant levels on the physiology of an organism, it is essential to gain knowledge about its redoxome: the proteins whose activities are controlled by the oxidation status of their cysteine thiols. Here, we applied the quantitative redox proteomic method OxICAT to Saccharomyces cerevisiae and determined the in vivo thiol oxidation status of almost 300 different yeast proteins distributed among various cellular compartments. We found that a substantial number of cytosolic and mitochondrial proteins are partially oxidized during exponential growth. Our results suggest that prevailing redox conditions constantly control central cellular pathways by fine-tuning oxidation status and hence activity of these proteins. Treatment with sublethal H2O2 concentrations caused a subset of 41 proteins to undergo substantial thiol modifications, thereby affecting a variety of different cellular pathways, many of which are directly or indirectly involved in increasing oxidative stress resistance. Classification of the identified protein thiols according to their steady-state oxidation levels and sensitivity to peroxide treatment revealed that redox sensitivity of protein thiols does not predict peroxide sensitivity. Our studies provide experimental evidence that the ability of protein thiols to react to changing peroxide levels is likely governed by both thermodynamic and kinetic parameters, making predicting thiol modifications challenging and de novo identification of peroxide sensitive protein thiols indispensable.

Brandes, Nicolas; Reichmann, Dana; Tienson, Heather; Leichert, Lars I.; Jakob, Ursula

2011-01-01

37

Dissection Dissected.  

ERIC Educational Resources Information Center

|Discusses the role of dissection in science courses, examining essential lessons students can learn (such as developing an abiding respect for all forms of life, including the animal being dissected). Also presents a list of tips related to classroom dissection and comments on formaldehyde and formalin substitutes. (JN)|

Berman, William

1984-01-01

38

A comparative phosphoproteomic analysis of a human tumor metastasis model using a label-free quantitative approach.  

PubMed

Alterations in cellular phosphorylation patterns have been implicated in a number of diseases, including cancer, through multiple mechanisms. Herein we present a survey of the phosphorylation profiles of an isogenic pair of human cancer cell lines with opposite metastatic phenotype. Phosphopeptides were enriched from tumor cell lysates with titanium dioxide and zirconium dioxide, and identified with nano-LC-MS/MS using an automatic cross-validation of MS/MS and MS/MS/MS (MS2+MS3) data-dependent neutral loss method. A spectral counting quantitative strategy was applied to the two cell line samples on the MS2-only scan, which was implemented successively after each MS2+MS3 scan in the same sample. For all regulated phosphopeptides reported by spectral counting analysis, sequence and phosphorylation site assignments were validated by a MS2+MS3 data-dependent neutral loss method. With this approach, we identified over 70 phosphorylated sites on 27 phosphoproteins as being differentially expressed with respect to tumor cell phenotype. The altered expression levels of proteins identified by LC-MS/MS were validated using Western blotting. Using network pathway analysis, we observed that the majority of the differentially expressed proteins were highly interconnected and belong to two major intracellular signaling pathways. Our findings suggest that the phosphorylation of isoform A of lamin A/C and GTPase activating protein binding protein 1 is associated with metastatic propensity. The study demonstrates a quantitative and comparative proteomics strategy to identify differential phosphorylation patterns in complex biological samples. PMID:20446291

Xie, Xiaolei; Feng, Shun; Vuong, Huy; Liu, Yashu; Goodison, Steve; Lubman, David M

2010-06-01

39

Quantitative Mitochondrial Phosphoproteomics Using iTRAQ on an LTQ-Orbitrap with High Energy Collision Dissociation  

PubMed Central

Using iTRAQ labeling and mass spectrometry on an LTQ-Orbitrap with HCD capability, we assessed relative changes in protein phosphorylation in the mitochondria upon physiological perturbation. As a reference reaction, we monitored the well-characterized regulation of pyruvate dehydrogenase (PDH) activity via phosphorylation/dephosphorylation by pyruvate dehydrogenase kinase/pyruvate dehydrogenase phosphatase in response to dichloroacetate, de-energization and Ca2+. Relative quantification of phosphopeptides of PDH-E1? subunit from porcine heart revealed dephosphorylation at three serine sites (Ser231, Ser292 and Ser299). Dephosphorylation at Ser292 (i.e., the inhibitory site) with DCA correlated with an activation of PDH activity as previously reported, consistent with our de-energization data. Calcium also dephosphorylated (i.e., activated) PDH thus confirming calcium activation of PDP. With this approach, we successfully monitored other phosphorylation sites of mitochondrial proteins including adenine nucleotide translocase, malate dehydrogenase and mitochondrial creatine kinase, etc. Among them four proteins exhibited phosphorylation changes with these physiological stimuli: (1) BCKDH-E1? subunit increased phosphorylation at Ser337 with DCA and de-energization; (2) apoptosis-inducing factor phosphorylation was elevated at Ser345 with calcium; (3) ATP synthase F1 complex ? subunit and (4) mitofilin dephosphorylated at Ser65 and Ser264 upon de-energization. This screening validated the iTRAQ/HCD technology as a method for functional quantitation of mitochondrial protein phosphorylation as well as providing insights into the regulation of mitochondria via phosphorylation.

Boja, Emily S.; Phillips, Darci; French, Stephanie A.; Harris, Robert A.; Balaban, Robert S.

2009-01-01

40

Quantitative mitochondrial phosphoproteomics using iTRAQ on an LTQ-Orbitrap with high energy collision dissociation.  

PubMed

With the use of iTRAQ labeling and mass spectrometry on an LTQ-Orbitrap with HCD capability, we assessed relative changes in protein phosphorylation in the mitochondria upon physiological perturbation. As a reference reaction, we monitored the well-characterized regulation of pyruvate dehydrogenase (PDH) activity via phosphorylation/dephosphorylation by pyruvate dehydrogenase kinase/pyruvate dehydrogenase phosphatase in response to dichloroacetate, de-energization and Ca2+. Relative quantification of phosphopeptides of PDH-E1alpha subunit from porcine heart revealed dephosphorylation at three serine sites (Ser231, Ser292 and Ser299). Dephosphorylation at Ser292 (i.e., the inhibitory site) with DCA correlated with an activation of PDH activity as previously reported, consistent with our de-energization data. Calcium also dephosphorylated (i.e., activated) PDH, thus, confirming calcium activation of PDP. With this approach, we successfully monitored other phosphorylation sites of mitochondrial proteins including adenine nucleotide translocase, malate dehydrogenase and mitochondrial creatine kinase. Among them, four proteins exhibited phosphorylation changes with these physiological stimuli: (1) BCKDH-E1alpha subunit increased phosphorylation at Ser337 with DCA and de-energization; (2) apoptosis-inducing factor phosphorylation was elevated at Ser345 with calcium; (3) ATP synthase F1 complex alpha subunit and (4) mitofilin dephosphorylated at Ser65 and Ser264 upon de-energization. This screening validated the iTRAQ/HCD technology as a method for functional quantitation of mitochondrial protein phosphorylation as well as providing insight into the regulation of mitochondria via phosphorylation. PMID:19694452

Boja, Emily S; Phillips, Darci; French, Stephanie A; Harris, Robert A; Balaban, Robert S

2009-10-01

41

Dissecting Dissection.  

ERIC Educational Resources Information Center

This journal features articles covering various aspects of dissection. "Biology--The Study of Life" (George Russell) offers students experiments that do not require using invasive procedures. "Animal Cruelty--Behind the Scenes" (Zoe Weil) describes sources of laboratory animals. "Doing without Dissection" (Juliana Texley) discusses objections over…

AV Magazine, 1996

1996-01-01

42

Phosphoproteomics of vasopressin signaling in the kidney  

PubMed Central

Protein phosphorylation plays a critical role in the signaling pathways regulating water and solute transport in the distal renal tubule (i.e., renal collecting duct). A central mediator in this process is the antidiuretic peptide hormone arginine vasopressin, which regulates a number of transport proteins including water channel aquaporin-2 and urea transporters (UT-A1 and UT-A3). Within the past few years, tandem mass spectrometry-based proteomics has played a pivotal role in revealing global changes in the phosphoproteome in response to vasopressin signaling in the renal collecting duct. This type of large-scale ‘shotgun’ approach has resulted in an exponential increase in the number of phosphoproteins known to be regulated by vasopressin and has expanded on the established signaling mechanisms and kinase pathways regulating collecting duct physiology. This article will provide a brief background on vasopressin action, will highlight a number of recent quantitative phosphoproteomic studies in both native rat kidney and cultured collecting duct cells, and will conclude with a perspective focused on emerging trends in the field of phosphoproteomics.

Hoffert, Jason D; Pisitkun, Trairak; Knepper, Mark A

2012-01-01

43

Phosphoproteomics and cancer research.  

PubMed

Protein phosphorylation plays key roles in the regulation of normal and cancer cells. It is a highly dynamic process. Protein kinases are the targets of several new cancer drugs and drug candidates. However, some of the main issues related to new drugs are how they function and the selection of those patients that will likely respond best to a particular treatment regime. There is an urgent need to understand and monitor kinase signalling pathways. Phosphoproteomics requires the enrichment of phosphorylated proteins or peptides from tissue or bodily fluids, and the application of technologies such as mass spectrometry (MS) to the identification and quantification of protein phosphorylation sites. As the field develops it will provide pharmacodynamic readouts of disease states and cellular drug responses in tumour samples. There have been a number of recent advances, but there are still technical hurdles and bioinformatics challenges that need to be addressed. PMID:19531450

Ashman, Keith; Villar, Elena López

2009-06-01

44

Dissecting the regulation of fructan metabolism in perennial ryegrass (Lolium perenne) with quantitative trait locus mapping.  

PubMed

Quantitative trait locus (QTL) mapping, which can be a useful tool for dissecting complex traits, has been used here to study the regulation of fructan metabolism in temperate forage grasses. An F2 mapping family, derived from a high water-soluble carbohydrate (WSC) x low WSC cross, was used to map fructans and the other components of WSC (sucrose, glucose and fructose) in leaves and tiller bases of perennial ryegrass (Lolium perenne) in spring and autumn. To characterize regions of the genome that control basic carbohydrate metabolism, a strategy to minimize the impact of genotype (G) x environment (E), and E-effects on the characterization of G-effects, was adopted. Most traits were highly variable within the family. There was also considerable year-to-year environmental variation. However, significant genetic effects were detected, and several traits had high broad-sense heritability. QTL were identified on chromosomes 1, 2, 5 and 6. Leaf and tiller base QTL did not coincide. Individual QTL explained between 8 and 59% of the total phenotypic variation in the traits. Fructan turnover, metabolism and their genetic control, and the effect of environment, are discussed in the context of the results. PMID:16390418

Turner, L B; Cairns, A J; Armstead, I P; Ashton, J; Skøt, K; Whittaker, D; Humphreys, M O

2006-01-01

45

Taking Aim at Shotgun Phosphoproteomics  

PubMed Central

Shotgun phosphoproteomics employs liquid chromatography-coupled tandem mass spectrometry (LC-MS/MS) to analyze phosphopeptides from complex protein mixtures, allowing detection and quantification of phosphorylation events on a global scale. Within the past few years, this powerful technique has been used to uncover novel phosphorylation sites as well as explore changes in protein phosphorylation during cellular signaling in various systems. This review presents a general overview of current phosphoproteomic methodologies, including summaries of various approaches to phosphopeptide enrichment, alternative MS fragmentation strategies, and the latest software for analysis of phosphopeptide data sets.

Hoffert, Jason D.; Knepper, Mark A.

2008-01-01

46

Phosphoproteomics-based network medicine.  

PubMed

One of the major tasks of phosphoproteomics is providing potential biomarkers for either diagnosis or drug targets in medical applications. Because most complex diseases are due to the actions of multiple genes/proteins, the identification of complex phospho-signatures containing multiple phosphorylation events within phosphoproteomics-based networks generates more efficient and robust biomarkers than a single, differentially phosphorylated substrate or site. Here, we briefly summarize the current efforts and progress in this newly emerging field of phosphoproteomics-based network medicine by reviewing the computational (re)construction of phosphorylation-mediated signaling networks from unannotated phosphoproteomic data, the discovery of robust network phospho-signatures and the application of these signatures for classifying cancers and predicting drug responses. The challenges as well as the potential advantages are evaluated and discussed. Although the current techniques are at present far from mature, we believe that such a systematic approach as we describe can generate more useful and robust biomarkers for biomedical usage, even at the current stage of development. PMID:23751130

Liu, Zexian; Wang, Yongbo; Xue, Yu

2013-06-28

47

Phosphoproteomics: new insights into cellular signaling  

Microsoft Academic Search

Developments in the field of phosphoproteomics have been fueled by the need simultaneously to monitor many different phosphoproteins within the signaling networks that coordinate responses to changes in the cellular environment. This article presents a brief review of phosphoproteomics with an emphasis on the biological insights that have been derived so far.

Marc Mumby; Deirdre Brekken

2005-01-01

48

Impact of phosphoproteomics on studies of bacterial physiology.  

PubMed

Protein phosphorylation on serine, threonine and tyrosine is recognized as a major tool of signal transduction in bacteria. However, progress in the field has been hampered by the lack of global and site-specific data on bacterial phosphoproteomes. Recent advances in mass spectrometry-based proteomics have encouraged bacteriologists to start using powerful gel-free approaches for global detection of phosphorylated proteins. These studies have generated large data sets of proteins phosphorylated on serine, threonine and tyrosine, with identified phosphorylation sites which represent an excellent starting point for in-depth physiological characterization of kinases and their substrates. The list of phosphorylated proteins inspired a number of physiological studies in which the identity of the phosphorylation site facilitated the elucidation of molecular mechanisms of signaling and regulation. Bacterial phosphoproteomics also provided interesting insights into the evolutionary aspects of protein phosphorylation. The field is rapidly embracing quantitative mass spectrometry strategies, comparing phosphoproteome dynamics in changing conditions and aiming to reconstruct the entire regulatory networks by linking kinases to their physiological substrates. PMID:22091997

Mijakovic, Ivan; Macek, Boris

2011-11-28

49

Proteome, phosphoproteome, and N-glycoproteome are quantitatively preserved in formalin-fixed paraffin-embedded tissue and analyzable by high-resolution mass spectrometry.  

PubMed

Tissue samples in biobanks are typically formalin-fixed and paraffin-embedded (FFPE), in which form they are preserved for decades. It has only recently been shown that proteins in FFPE tissues can be identified by mass spectrometry-based proteomics but analysis of post-translational modifications is thought to be difficult or impossible. The filter aided sample preparation (FASP) method can analyze proteomic samples solubilized in high concentrations of SDS and we use this feature to develop a simple protocol for FFPE analysis. Combination with simple pipet-tip based peptide fractionation identified about 5000 mouse liver proteins in 24 h measurement time-the same as in fresh tissue. Results from the FFPE-FASP procedure do not indicate any discernible changes due to storage time, hematoxylin staining or laser capture microdissection. We compared fresh against FFPE tissue using the SILAC mouse and found no significant qualitative or quantitative differences between these samples either at the protein or the peptide level. Application of our FFPE-FASP protocol to phosphorylation and N-glycosylation pinpointed nearly 5000 phosphosites and 1500 N-glycosylation sites. Analysis of FFPE tissue of the SILAC mouse revealed that these post-translational modifications were quantitatively preserved. Thus, FFPE biobank material can be analyzed by quantitative proteomics at the level of proteins and post-translational modifications. PMID:20469934

Ostasiewicz, Pawe?; Zielinska, Dorota F; Mann, Matthias; Wi?niewski, Jacek R

2010-07-01

50

Chemical Visualization of Phosphoproteomes on Membrane*  

PubMed Central

With new discoveries of important roles of phosphorylation on a daily basis, phospho-specific antibodies, as the primary tool for on-membrane detection of phosphoproteins, face enormous challenges. To address an urgent need for convenient and reliable analysis of phosphorylation events, we report a novel strategy for sensitive phosphorylation analysis in the Western blotting format. The chemical reagent, which we termed pIMAGO, is based on a multifunctionalized soluble nanopolymer and is capable of selectively binding to phosphorylated residues independent of amino acid microenvironment, thus offering great promise as a universal tool in biological analyses where the site of phosphorylation is not known or its specific antibody is not available. The specificity and sensitivity of the approach was first examined using a mixture of standard proteins. The method was then applied to monitor phosphorylation changes in in vitro kinase and phosphatase assays. Finally, to demonstrate the unique ability of pIMAGO to measure endogenous phosphorylation, we used it to visualize and determine the differences in phosphorylated proteins that interact with wild-type and kinase dead mutant of Polo-like kinase 1 during mitosis, the results of which were further confirmed by a quantitative phosphoproteomics experiment.

Iliuk, Anton; Liu, X. Shawn; Xue, Liang; Liu, Xiaoqi; Tao, W. Andy

2012-01-01

51

Global analysis of neuronal phosphoproteome regulation by chondroitin sulfate proteoglycans.  

PubMed

Chondroitin sulfate proteoglycans (CSPGs) are major components of the extracellular matrix which mediate inhibition of axonal regeneration after injury to the central nervous system (CNS). Several neuronal receptors for CSPGs have recently been identified; however, the signaling pathways by which CSPGs restrict axonal growth are still largely unknown. In this study, we applied quantitative phosphoproteomics to investigate the global changes in protein phosphorylation induced by CSPGs in primary neurons. In combination with isobaric Tags for Relative and Absolute Quantitation (iTRAQ) labeling, strong cation exchange chromatography (SCX) fractionation, immobilized metal affinity chromatography (IMAC) and LC-MS/MS, we identified and quantified 2214 unique phosphopeptides corresponding to 1118 phosphoproteins, with 118 changing significantly in abundance with CSPG treatment. The proteins that were regulated by CSPGs included key components of synaptic vesicle trafficking, axon guidance mediated by semaphorins, integrin signaling, cadherin signaling and EGF receptor signaling pathways. A significant number of the regulated proteins are cytoskeletal and related proteins that have been implicated in regulating neurite growth. Another highly represented protein category regulated by CSPGs is nucleic acid binding proteins involved in RNA post-transcriptional regulation. Together, by screening the overall phosphoproteome changes induced by CSPGs, this data expand our understanding of CSPG signaling, which provides new insights into development of strategies for overcoming CSPG inhibition and promoting axonal regeneration after CNS injury. PMID:23527152

Yu, Panpan; Pisitkun, Trairak; Wang, Guanghui; Wang, Rong; Katagiri, Yasuhiro; Gucek, Marjan; Knepper, Mark A; Geller, Herbert M

2013-03-18

52

Dissecting Quantitative Trait Loci for Boron Efficiency across Multiple Environments in Brassica napus  

PubMed Central

High yield is the most important goal in crop breeding, and boron (B) is an essential micronutrient for plants. However, B deficiency, leading to yield decreases, is an agricultural problem worldwide. Brassica napus is one of the most sensitive crops to B deficiency, and considerable genotypic variation exists among different cultivars in response to B deficiency. To dissect the genetic basis of tolerance to B deficiency in B. napus, we carried out QTL analysis for seed yield and yield-related traits under low and normal B conditions using the double haploid population (TNDH) by two-year and the BQDH population by three-year field trials. In total, 80 putative QTLs and 42 epistatic interactions for seed yield, plant height, branch number, pod number, seed number, seed weight and B efficiency coefficient (BEC) were identified under low and normal B conditions, singly explaining 4.15–23.16% and 0.53–14.38% of the phenotypic variation. An additive effect of putative QTLs was a more important controlling factor than the additive-additive effect of epistatic interactions. Four QTL-by-environment interactions and 7 interactions between epistatic interactions and the environment contributed to 1.27–4.95% and 1.17–3.68% of the phenotypic variation, respectively. The chromosome region on A2 of SYLB-A2 for seed yield under low B condition and BEC-A2 for BEC in the two populations was equivalent to the region of a reported major QTL, BE1. The B. napus homologous genes of Bra020592 and Bra020595 mapped to the A2 region and were speculated to be candidate genes for B efficiency. These findings reveal the complex genetic basis of B efficiency in B. napus. They provide a basis for the fine mapping and cloning of the B efficiency genes and for breeding B-efficient cultivars by marker-assisted selection (MAS).

Zhao, Zunkang; Wu, Likun; Nian, Fuzhao; Ding, Guangda; Shi, Taoxiong; Zhang, Didi; Shi, Lei; Xu, Fangsen; Meng, Jinling

2012-01-01

53

Phosphoproteomic analyses reveal signaling pathways that facilitate lytic gammaherpesvirus replication.  

PubMed

Lytic gammaherpesvirus (GHV) replication facilitates the establishment of lifelong latent infection, which places the infected host at risk for numerous cancers. As obligate intracellular parasites, GHVs must control and usurp cellular signaling pathways in order to successfully replicate, disseminate to stable latency reservoirs in the host, and prevent immune-mediated clearance. To facilitate a systems-level understanding of phosphorylation-dependent signaling events directed by GHVs during lytic replication, we utilized label-free quantitative mass spectrometry to interrogate the lytic replication cycle of murine gammaherpesvirus-68 (MHV68). Compared to controls, MHV68 infection regulated by 2-fold or greater ca. 86% of identified phosphopeptides - a regulatory scale not previously observed in phosphoproteomic evaluations of discrete signal-inducing stimuli. Network analyses demonstrated that the infection-associated induction or repression of specific cellular proteins globally altered the flow of information through the host phosphoprotein network, yielding major changes to functional protein clusters and ontologically associated proteins. A series of orthogonal bioinformatics analyses revealed that MAPK and CDK-related signaling events were overrepresented in the infection-associated phosphoproteome and identified 155 host proteins, such as the transcription factor c-Jun, as putative downstream targets. Importantly, functional tests of bioinformatics-based predictions confirmed ERK1/2 and CDK1/2 as kinases that facilitate MHV68 replication and also demonstrated the importance of c-Jun. Finally, a transposon-mutant virus screen identified the MHV68 cyclin D ortholog as a viral protein that contributes to the prominent MAPK/CDK signature of the infection-associated phosphoproteome. Together, these analyses enhance an understanding of how GHVs reorganize and usurp intracellular signaling networks to facilitate infection and replication. PMID:24068923

Stahl, James A; Chavan, Shweta S; Sifford, Jeffrey M; Macleod, Veronica; Voth, Daniel E; Edmondson, Ricky D; Forrest, J Craig

2013-09-19

54

Phosphoproteomic Analyses Reveal Signaling Pathways That Facilitate Lytic Gammaherpesvirus Replication  

PubMed Central

Lytic gammaherpesvirus (GHV) replication facilitates the establishment of lifelong latent infection, which places the infected host at risk for numerous cancers. As obligate intracellular parasites, GHVs must control and usurp cellular signaling pathways in order to successfully replicate, disseminate to stable latency reservoirs in the host, and prevent immune-mediated clearance. To facilitate a systems-level understanding of phosphorylation-dependent signaling events directed by GHVs during lytic replication, we utilized label-free quantitative mass spectrometry to interrogate the lytic replication cycle of murine gammaherpesvirus-68 (MHV68). Compared to controls, MHV68 infection regulated by 2-fold or greater ca. 86% of identified phosphopeptides – a regulatory scale not previously observed in phosphoproteomic evaluations of discrete signal-inducing stimuli. Network analyses demonstrated that the infection-associated induction or repression of specific cellular proteins globally altered the flow of information through the host phosphoprotein network, yielding major changes to functional protein clusters and ontologically associated proteins. A series of orthogonal bioinformatics analyses revealed that MAPK and CDK-related signaling events were overrepresented in the infection-associated phosphoproteome and identified 155 host proteins, such as the transcription factor c-Jun, as putative downstream targets. Importantly, functional tests of bioinformatics-based predictions confirmed ERK1/2 and CDK1/2 as kinases that facilitate MHV68 replication and also demonstrated the importance of c-Jun. Finally, a transposon-mutant virus screen identified the MHV68 cyclin D ortholog as a viral protein that contributes to the prominent MAPK/CDK signature of the infection-associated phosphoproteome. Together, these analyses enhance an understanding of how GHVs reorganize and usurp intracellular signaling networks to facilitate infection and replication.

Stahl, James A.; Chavan, Shweta S.; Sifford, Jeffrey M.; MacLeod, Veronica; Voth, Daniel E.; Edmondson, Ricky D.; Forrest, J. Craig

2013-01-01

55

Dissecting eukaryotic cells by coherent phase microscopy: quantitative analysis of quiescent and activated T lymphocytes  

NASA Astrophysics Data System (ADS)

We present a concept for quantitative characterization of a functional state of an individual eukaryotic cell based on interference imaging. The informative parameters of the phase images of quiescent and mitogen-activated T lymphocytes included the phase thickness, phase volume, the area, and the size of organelles. These parameters were obtained without a special hypothesis about cell structure. Combinations of these parameters generated a ``phase portrait'' of the cell. A simplified spherical multilayer optic model of a T lymphocyte was used to calculate the refractivity profile, to identify structural elements of the image with the organelles, and to interpret the parameters of the phase portrait. The values of phase image parameters underwent characteristic changes in the course of mitogenic stimulation of T cells; thereby, the functional state of individual cells can be described using these parameters. Because the values of the components of the phase portrait are measured in absolute units, it is possible to compare the parameters of images obtained with different interference microscopes. Thus, the analysis of phase portraits provides a new and perspective approach for quantitative, real-time analysis of subcellular structure and physiologic state of an individual cell.

Tychinsky, Vladimir P.; Kretushev, Alexander V.; Vyshenskaya, Tatiana V.; Shtil, Alexander A.

2012-07-01

56

Dissecting eukaryotic cells by coherent phase microscopy: quantitative analysis of quiescent and activated T lymphocytes  

PubMed Central

Abstract. We present a concept for quantitative characterization of a functional state of an individual eukaryotic cell based on interference imaging. The informative parameters of the phase images of quiescent and mitogen-activated T lymphocytes included the phase thickness, phase volume, the area, and the size of organelles. These parameters were obtained without a special hypothesis about cell structure. Combinations of these parameters generated a “phase portrait” of the cell. A simplified spherical multilayer optic model of a T lymphocyte was used to calculate the refractivity profile, to identify structural elements of the image with the organelles, and to interpret the parameters of the phase portrait. The values of phase image parameters underwent characteristic changes in the course of mitogenic stimulation of T cells; thereby, the functional state of individual cells can be described using these parameters. Because the values of the components of the phase portrait are measured in absolute units, it is possible to compare the parameters of images obtained with different interference microscopes. Thus, the analysis of phase portraits provides a new and perspective approach for quantitative, real-time analysis of subcellular structure and physiologic state of an individual cell.

Tychinsky, Vladimir P.; Kretushev, Alexander V.; Vyshenskaya, Tatiana V.; Shtil, Alexander A.

2012-01-01

57

Technical phosphoproteomic and bioinformatic tools useful in cancer research  

PubMed Central

Reversible protein phosphorylation is one of the most important forms of cellular regulation. Thus, phosphoproteomic analysis of protein phosphorylation in cells is a powerful tool to evaluate cell functional status. The importance of protein kinase-regulated signal transduction pathways in human cancer has led to the development of drugs that inhibit protein kinases at the apex or intermediary levels of these pathways. Phosphoproteomic analysis of these signalling pathways will provide important insights for operation and connectivity of these pathways to facilitate identification of the best targets for cancer therapies. Enrichment of phosphorylated proteins or peptides from tissue or bodily fluid samples is required. The application of technologies such as phosphoenrichments, mass spectrometry (MS) coupled to bioinformatics tools is crucial for the identification and quantification of protein phosphorylation sites for advancing in such relevant clinical research. A combination of different phosphopeptide enrichments, quantitative techniques and bioinformatic tools is necessary to achieve good phospho-regulation data and good structural analysis of protein studies. The current and most useful proteomics and bioinformatics techniques will be explained with research examples. Our aim in this article is to be helpful for cancer research via detailing proteomics and bioinformatic tools.

2011-01-01

58

Quantitative dissection of hydrogen bond-mediated proton transfer in the ketosteroid isomerase active site.  

PubMed

Hydrogen bond networks are key elements of protein structure and function but have been challenging to study within the complex protein environment. We have carried out in-depth interrogations of the proton transfer equilibrium within a hydrogen bond network formed to bound phenols in the active site of ketosteroid isomerase. We systematically varied the proton affinity of the phenol using differing electron-withdrawing substituents and incorporated site-specific NMR and IR probes to quantitatively map the proton and charge rearrangements within the network that accompany incremental increases in phenol proton affinity. The observed ionization changes were accurately described by a simple equilibrium proton transfer model that strongly suggests the intrinsic proton affinity of one of the Tyr residues in the network, Tyr16, does not remain constant but rather systematically increases due to weakening of the phenol-Tyr16 anion hydrogen bond with increasing phenol proton affinity. Using vibrational Stark spectroscopy, we quantified the electrostatic field changes within the surrounding active site that accompany these rearrangements within the network. We were able to model these changes accurately using continuum electrostatic calculations, suggesting a high degree of conformational restriction within the protein matrix. Our study affords direct insight into the physical and energetic properties of a hydrogen bond network within a protein interior and provides an example of a highly controlled system with minimal conformational rearrangements in which the observed physical changes can be accurately modeled by theoretical calculations. PMID:23798390

Sigala, Paul A; Fafarman, Aaron T; Schwans, Jason P; Fried, Stephen D; Fenn, Timothy D; Caaveiro, Jose M M; Pybus, Brandon; Ringe, Dagmar; Petsko, Gregory A; Boxer, Steven G; Herschlag, Daniel

2013-06-24

59

Genetic dissection of quantitative trait locus for ethanol sensitivity in long- and short-sleep mice.  

PubMed

Interval-specific congenic strains (ISCS) allow fine mapping of a quantitative trait locus (QTL), narrowing its confidence interval by an order of magnitude or more. In earlier work, we mapped four QTL specifying differential ethanol sensitivity, assessed by loss of righting reflex because of ethanol (LORE), in the inbred long-sleep (ILS) and inbred short-sleep (ISS) strains, accounting for approximately 50% of the genetic variance for this trait. Subsequently, we generated reciprocal congenic strains in which each full QTL interval from ILS was bred onto the ISS background and vice versa. An earlier paper reported construction and results of the ISCS on the ISS background; here, we describe this process and report results on the ILS background. We developed multiple ISCS for each Lore QTL in which the QTL interval was broken into a number of smaller intervals. For each of the four QTL regions (chromosomes 1, 2, 11 and 15), we were successful in reducing the intervals significantly. Multiple, positive strains were overlapped to generate a single, reduced interval. Subsequently, this reduced region was overlaid on previous reductions from the ISS background congenics, resulting in substantial reductions in all QTL regions by approximately 75% from the initial mapping study. Genes with sequence or expression polymorphisms in the reduced intervals are potential candidates; evidence for these is presented. Genetic background effects can be important in detection of single QTL; combining this information with the generation of congenics on both backgrounds, as described here, is a powerful approach for fine mapping QTL. PMID:18363857

Bennett, B; Carosone-Link, P; Beeson, M; Gordon, L; Phares-Zook, N; Johnson, T E

2008-03-21

60

New findings of kinase switching in gastrointestinal stromal tumor under imatinib using phosphoproteomic analysis.  

PubMed

Despite the revolutionary effects of imatinib on advanced gastrointestinal stromal tumors (GISTs), most patients eventually develop disease progression following primary resistance or acquired resistance driven by secondary-resistant mutations. Even in radiographically vanishing lesions, pathology has revealed persistent viable cells during imatinib therapy, which could lead to the emergence of drug-resistant clones. To uncover the mechanisms underlying these clinical issues, here we examined imatinib-induced phosphoproteomic alterations in GIST-T1 cells, using our quantitative tyrosine phosphoproteomic analysis method, which combined immunoaffinity enrichment of phosphotyrosine-containing peptides with isobaric tags for relative and absolute quantitation (iTRAQ) technology. Using this approach, we identified 171 tyrosine phosphorylation sites spanning 134 proteins, with 11 proteins exhibiting greater than 1.5-fold increases in tyrosine phosphorylation. Among them, we evaluated FYN and focal adhesion kinase (FAK), both of which are reportedly involved in proliferation and malignant alteration of tumors. We confirmed increased tyrosine phosphorylation of both kinases by western blotting. Inhibition of FYN and FAK phosphorylation each increased tumor cell sensitivity to imatinib. Furthermore, a FAK-selective inhibitor (TAG372) induced apoptosis of imatinib-resistant GIST-T1 cells and decreased the imatinib IC50 . These results indicate that FYN or FAK might be potential therapeutic targets to overcome resistance to imatinib in GISTs. Additionally, we showed that the iTRAQ-based quantitative phosphotyrosine-focused phosphoproteomic approach is a powerful method for screening phosphoproteins associated with drug resistance. PMID:23716303

Takahashi, Tsuyoshi; Serada, Satoshi; Ako, Maiko; Fujimoto, Minoru; Miyazaki, Yasuaki; Nakatsuka, Rie; Ikezoe, Takayuki; Yokoyama, Akihito; Taguchi, Takahiro; Shimada, Kazuki; Kurokawa, Yukinori; Yamasaki, Makoto; Miyata, Hiroshi; Nakajima, Kiyokazu; Takiguchi, Shuji; Mori, Masaki; Doki, Yuichiro; Naka, Tetsuji; Nishida, Toshirou

2013-06-14

61

Phosphoproteomics characterization of novel phosphorylated sites of lens proteins from normal and cataractous human eye lenses  

PubMed Central

Purpose Post-translational modification (PTM) of lens proteins is believed to play various roles in age-related lens function and development. Among the different types of PTM, phosphorylation is most noteworthy to play a major role in the regulation of various biosignaling pathways in relation to metabolic processes and cellular functions. The present study reported the quantitative analysis of the in vivo phosphoproteomics profiles of human normal and cataractous lenses with the aim of identifying specific phosphorylation sites which may provide insights into the physiologic significance of phosphorylation in relation to cataract formation. Methods To improve detection sensitivity of low abundant proteins, we first adopted SDS-gel electrophoresis fractionation of lens extracts to identify and compare the protein compositions between normal and cataractous lenses, followed by tryptic digestion, enrichment of phosphopeptides by immobilized metal affinity chromatography (IMAC) and nano-liquid chromatography coupled tandem mass spectrometry (nanoLC-MS/MS) analysis. Results By comprehensively screening of the phosphoproteome in normal and cataractous lenses, we identified 32 phosphoproteins and 73 phosphorylated sites. The most abundantly phosphorylated proteins are two subunits of ?-crystallin, i.e., ?B1-crystallin (12%) and ?B2-crystallin (12%). Moreover, serine was found to be the most abundantly phosphorylated residue (72%) in comparison with threonine (24%) and tyrosine (4%) in the lens phosphoproteome. The quantitative analysis revealed significant and distinct changes of 19 phosphoproteins corresponding to 28 phosphorylated sites between these two types of human lenses, including 20 newly discovered novel phosphorylation sites on lens proteins. Conclusions The shotgun phosphoproteomics approach to characterize protein phosphorylation may be adapted and extended to the comprehensive analysis of other types of post-translational modification of lens proteins in vivo. The identification of these novel phosphorylation sites in lens proteins that showed differential expression in the cataractous lens may bear some unknown physiologic significance and provide insights into phosphorylation-related human eye diseases, which warrant further investigation in the future.

Huang, Chun-Hao; Wang, Yi-Ting; Tsai, Chia-Feng; Chen, Yu-Ju; Lee, Jiahn-Shing

2011-01-01

62

Site-specific analysis of bacterial phosphoproteomes.  

PubMed

Protein phosphorylation on serine, threonine and tyrosine is established as an important regulatory modification in bacteria. A growing number of studies employing mass spectrometry-based proteomics report large protein phosphorylation datasets, providing precise evidence for in-vivo phosphorylation that is especially suitable for functional follow-up. Here, we provide an overview of the strategies currently used in bacterial phosphoproteomics, with an emphasis on gel-free proteomics and approaches that enable global detection of phosphorylation sites in bacterial proteins. The proteomics technology has matured sufficiently to permit routine characterization of phosphoproteomes and phosphopeptides with high sensitivity; we argue that the next challenge in the field will be the large-scale detection of protein kinase and phosphatase substrates and their integration into regulatory networks of the bacterial cell. PMID:21726046

Macek, Boris; Mijakovic, Ivan

2011-07-04

63

Identification of Targets of c-Src Tyrosine Kinase by Chemical Complementation and Phosphoproteomics*  

PubMed Central

The cellular proto-oncogene c-Src is a nonreceptor tyrosine kinase involved in cell growth and cytoskeletal regulation. Despite being dysregulated in a variety of human cancers, its precise functions are not fully understood. Identification of the substrates of c-Src remains a major challenge, because there is no simple way to directly stimulate its activity. Here we combine the chemical rescue of mutant c-Src and global quantitative phosphoproteomics to obtain the first high resolution snapshot of the range of tyrosine phosphorylation events that occur in the cell immediately after specific c-Src stimulation. After enrichment by anti-phosphotyrosine antibodies, we identified 29 potential novel c-Src substrate proteins. Tyrosine phosphopeptide mapping allowed the identification of 382 nonredundant tyrosine phosphopeptides on 213 phosphoproteins. Stable isotope labeling of amino acids in cell culture-based quantitation allowed the detection of 97 nonredundant tyrosine phosphopeptides whose level of phosphorylation is increased by c-Src. A large number of previously uncharacterized c-Src putative protein targets and phosphorylation sites are presented here, a majority of which play key roles in signaling and cytoskeletal networks, particularly in cell adhesion. Integrin signaling and focal adhesion kinase signaling pathway are two of the most altered pathways upon c-Src activation through chemical rescue. In this context, our study revealed the temporal connection between c-Src activation and the GTPase Rap1, known to stimulate integrin-dependent adhesion. Chemical rescue of c-Src provided a tool to dissect the spatiotemporal mechanism of activation of the Rap1 guanine exchange factor, C3G, one of the identified potential c-Src substrates that plays a role in focal adhesion signaling. In addition to unveiling the role of c-Src in the cell and, specifically, in the Crk-C3G-Rap1 pathway, these results exemplify a strategy for obtaining a comprehensive understanding of the functions of nonreceptor tyrosine kinases with high specificity and kinetic resolution.

Ferrando, Isabel Martinez; Chaerkady, Raghothama; Zhong, Jun; Molina, Henrik; Jacob, Harrys K.C.; Herbst-Robinson, Katie; Dancy, Beverley M.; Katju, Vikram; Bose, Ron; Zhang, Jin; Pandey, Akhilesh; Cole, Philip A.

2012-01-01

64

Reproducibility of quantitative fiber tracking measurements in diffusion tensor imaging of frontal lobe tracts: A protocol based on the fiber dissection technique  

PubMed Central

Background: Diffusion tensor imaging (DTI)-based tractography is a noninvasive in vivo method for tracing white matter bundles. This raises possibilities for qualitative and quantitative assessment of the structural organization of tracts. Nevertheless, questions remain about neuroanatomical accuracy, reproducibility for clinical purposes, and accessibility of the best method for broader application. The aim of this study was to combine the fiber dissection technique and tractography to provide more pertinent insight into brain anatomy and, as a result, to test a protocol for reconstruction of six major frontal lobe tracts. Methods: A combination of fiber dissection of formalin-fixed brain tissue after freezing (Klingler's technique) and virtual dissection (tractography) was used to develop a protocol to reconstruct major frontal tracts. Apparent diffusion coefficient (ADC), fractional anisotropy (FA), number of voxels (NVO), volume (VOL), number (NTR), and length (LEN) of tracts were evaluated to assess intra- and interobserver reproducibility. Statistical reliability was evaluated using intraclass correlation coefficients (ICCs) and the Pearson association coefficient (r). Results: The virtual dissection obtained by tractography seemed to reproduce the anatomic knowledge of the white matter tracts obtained through the classic method. In reliability study, most ICC and r values corresponded at least to large correlation. The magnitude of correlation was very high (ICC 0.7-0.9) or almost perfect (ICC 0.9-1.0) for the FA and ADC measures of every tract studied. Conclusion: The DTI protocol proposed herein provided a reliable method for analysis of reconstructed frontal lobe tracts, especially for the FA and ADC variables.

Dini, Leandro I.; Vedolin, Leonardo M.; Bertholdo, Debora; Grando, Rafael D.; Mazzola, Alessandro; Dini, Simone A.; Isolan, Gustavo R.; da Costa, Jaderson C.; Campero, Alvaro

2013-01-01

65

Increased confidence in large-scale phosphoproteomics data by complementary mass spectrometric techniques and matching of phosphopeptide data sets.  

PubMed

Large-scale phosphoproteomics studies are of great interest due to their potential for the dissection of signaling pathways controlled by protein kinases. Recent advances in mass spectrometry (MS)-based phosphoproteomic techniques offer new opportunities to profile protein kinase activities in a comprehensive manner. However, this increasingly used approach still poses many analytical challenges. On one hand, high stringency criteria for phosphopeptide identification based on MS/MS data are needed in order to avoid false positives; however, on the other hand, these stringent criteria also result in the introduction of many false negatives. In the current report, we employ different mass spectrometric techniques for large-scale phosphoproteomics in order to reduce the presence of false negatives and enhance data confidence. A LTQ-Orbitrap LC-MS/MS platform identified approximately 3 times more phosphopeptides than Q-TOF LC-MS/MS instrumentation (4308 versus 1485 identifications, respectively). In both cases, collision induced dissociation (CID) was used to fragment peptides. Interestingly, the two platforms produced complementary data as many of the low scoring phosphopeptide ions identified by LTQ-Orbitrap MS/MS gave rise to high score identifications by Q-TOF MS/MS analysis, and vice versa. In fact, approximately 450 phosphopeptides identified by the Q-TOF instrument were not identified by the LTQ-Orbitrap. Further data comparison revealed the extent of the problem: in one experiment, the estimated number of false negatives (1066) was close to the number of identified phosphopeptides (1485). This work demonstrates that by using standard procedures for phosphopeptide identification the number of false negatives can be even greater than the number of false positives. We propose using historical phosphoproteomic data and spectral matching algorithms in order to efficiently minimize false negative rates. PMID:19537829

Alcolea, Maria P; Kleiner, Oliver; Cutillas, Pedro R

2009-08-01

66

Toward defining the phosphoproteome of Xenopus laevis embryos  

PubMed Central

Phosphorylation is universally used for controlling protein function, but knowledge of the phosphoproteome in vertebrate embryos has been limited. However, recent technical advances make it possible to define an organism's phosphoproteome at a more comprehensive level. Xenopus laevis offers established advantages for analyzing the regulation of protein function by phosphorylation. Functionally unbiased, comprehensive information about the Xenopus phosphoproteome would provide a powerful guide for future studies of phosphorylation in a developmental context. To this end, we performed a phosphoproteomic analysis of Xenopus oocytes, eggs, and embryos using recently developed mass spectrometry methods. We identified 1,441 phosphorylation sites present on 654 different Xenopus proteins, including hundreds of previously unknown phosphorylation sites. This approach identified several phosphorylation sites described in the literature and/or evolutionarily conserved in other organisms, validating the data's quality. These data will serve as a powerful resource for the exploration of phosphorylation and protein function within a developmental context.

McGivern, Jered V.; Swaney, Danielle L.; Coon, Joshua J.; Sheets, Michael D.

2010-01-01

67

Increasing phosphoproteomic coverage through sequential digestion by complementary proteases  

PubMed Central

Protein phosphorylation is a reversible post-translational modification known to regulate protein function, subcellular localization, complex formation, and protein degradation. Detailed phosphoproteomic information is critical to kinomic studies of signal transduction and for elucidation of cancer biomarkers, such as in non-small cell lung adenocarcinoma, where phosphorylation is commonly dysregulated. However, the collection and analysis of phosphorylation data remains a difficult problem. The low concentrations of phosphopeptides in complex biological mixtures as well as challenges inherent in their chemical nature have limited phosphoproteomic characterization and some phosphorylation sites are inaccessible by traditional workflows. We developed a sequential digestion method using complementary proteases, Glu-C and trypsin, to increase phosphoproteomic coverage and supplement traditional approaches. The sequential digestion method is more productive than workflows utilizing only Glu-C and we evaluated the orthogonality of the sequential digestion method relative to replicate trypsin-based analyses. Finally, we demonstrate the ability of the sequential digestion method to access new regions of the phosphoproteome by comparison to existing public phosphoproteomic databases. Our approach increases coverage of the human lung cancer phosphoproteome by accessing both new phosphoproteins and novel phosphorylation site information.

Gilmore, Jason M.; Kettenbach, Arminja N.; Gerber, Scott A.

2011-01-01

68

Phosphoproteomic analysis of Her2/neu signaling and inhibition  

PubMed Central

Her2/neu (Her2) is a tyrosine kinase belonging to the EGF receptor (EGFR)/ErbB family and is overexpressed in 20–30% of human breast cancers. We sought to characterize Her2 signal transduction pathways further by using MS-based quantitative proteomics. Stably transfected cell lines overexpressing Her2 or empty vector were generated, and the effect of an EGFR and Her2 selective tyrosine kinase inhibitor, PD168393, on these cells was characterized. Quantitative measurements were obtained on 462 proteins by using the SILAC (stable isotope labeling with amino acids in cell culture) method to monitor three conditions simultaneously. Of these proteins, 198 showed a significant increase in tyrosine phosphorylation in Her2-overexpressing cells, and 81 showed a significant decrease in phosphorylation. Treatment of Her2-overexpressing cells with PD168393 showed rapid reversibility of the majority of the Her2-triggered phosphorylation events. Phosphoproteins that were identified included many known Her2 signaling molecules as well as known EGFR signaling proteins that had not been previously linked to Her2, such as Stat1, Dok1, and ?-catenin. Importantly, several previously uncharacterized Her2 signaling proteins were identified, including Axl tyrosine kinase, the adaptor protein Fyb, and the calcium-binding protein Pdcd-6/Alg-2. We also identified a phosphorylation site in Her2, Y877, which is located in the activation loop of the kinase domain, is distinct from the known C-terminal tail autophosphorylation sites, and may have important implications for regulation of Her2 signaling. Network modeling, which combined phosphoproteomic results with literature-curated protein–protein interaction data, was used to suggest roles for some of the previously unidentified Her2 signaling proteins.

Bose, Ron; Molina, Henrik; Patterson, A. Scott; Bitok, John K.; Periaswamy, Balamurugan; Bader, Joel S.; Pandey, Akhilesh; Cole, Philip A.

2006-01-01

69

Parallel proteomic and phosphoproteomic analyses of successive stages of maize leaf development.  

PubMed

We performed large-scale, quantitative analyses of the maize (Zea mays) leaf proteome and phosphoproteome at four developmental stages. Exploiting the developmental gradient of maize leaves, we analyzed protein and phosphoprotein abundance as maize leaves transition from proliferative cell division to differentiation to cell expansion and compared these developing zones to one another and the mature leaf blade. Comparison of the proteomes and phosphoproteomes suggests a key role for posttranslational regulation in developmental transitions. Analysis of proteins with cell wall- and hormone-related functions illustrates the utility of the data set and provides further insight into maize leaf development. We compare phosphorylation sites identified here to those previously identified in Arabidopsis thaliana. We also discuss instances where comparison of phosphorylated and unmodified peptides from a particular protein indicates tissue-specific phosphorylation. For example, comparison of unmodified and phosphorylated forms of PINFORMED1 (PIN1) suggests a tissue-specific difference in phosphorylation, which correlates with changes in PIN1 polarization in epidermal cells during development. Together, our data provide insights into regulatory processes underlying maize leaf development and provide a community resource cataloging the abundance and phosphorylation status of thousands of maize proteins at four leaf developmental stages. PMID:23933881

Facette, Michelle R; Shen, Zhouxin; Björnsdóttir, Fjola R; Briggs, Steven P; Smith, Laurie G

2013-08-09

70

Parallel Proteomic and Phosphoproteomic Analyses of Successive Stages of Maize Leaf Development[C][W][OPEN  

PubMed Central

We performed large-scale, quantitative analyses of the maize (Zea mays) leaf proteome and phosphoproteome at four developmental stages. Exploiting the developmental gradient of maize leaves, we analyzed protein and phosphoprotein abundance as maize leaves transition from proliferative cell division to differentiation to cell expansion and compared these developing zones to one another and the mature leaf blade. Comparison of the proteomes and phosphoproteomes suggests a key role for posttranslational regulation in developmental transitions. Analysis of proteins with cell wall– and hormone-related functions illustrates the utility of the data set and provides further insight into maize leaf development. We compare phosphorylation sites identified here to those previously identified in Arabidopsis thaliana. We also discuss instances where comparison of phosphorylated and unmodified peptides from a particular protein indicates tissue-specific phosphorylation. For example, comparison of unmodified and phosphorylated forms of PINFORMED1 (PIN1) suggests a tissue-specific difference in phosphorylation, which correlates with changes in PIN1 polarization in epidermal cells during development. Together, our data provide insights into regulatory processes underlying maize leaf development and provide a community resource cataloging the abundance and phosphorylation status of thousands of maize proteins at four leaf developmental stages.

Facette, Michelle R.; Shen, Zhouxin; Bjornsdottir, Fjola R.; Briggs, Steven P.; Smith, Laurie G.

2013-01-01

71

Phosphoproteomics Study on the Activated PKC?-Induced Cell Death.  

PubMed

The proteolytic activation of protein kinase C? (PKC?) generates a catalytic fragment called PKC?-CF, which induces cell death. However, the mechanisms underlying PKC?-CF-mediated cell death are largely unknown. On the basis of an engineering leukemic cell line with inducible expression of PKC?-CF, here we employ SILAC-based quantitative phosphoproteomics to systematically and dynamically investigate the overall phosphorylation events during cell death triggered by PKC?-CF expression. Totally, 3000 phosphorylation sites were analyzed. Considering the fact that early responses to PKC?-CF expression initiate cell death, we sought to identify pathways possibly related directly with PKC? by further analyzing the data set of phosphorylation events that occur in the initiation stage of cell death. Interacting analysis of this data set indicates that PKC?-CF triggers complicated networks to initiate cell death, and motif analysis and biochemistry verification reveal that several kinases in the downstream of PKC? conduct these networks. By analysis of the specific sequence motif of kinase-substrate, we also find 59 candidate substrates of PKC? from the up-regulated phosphopeptides, of which 12 were randomly selected for in vitro kinase assay and 9 were consequently verified as substrates of PKC?. To our greatest understanding, this study provides the most systematic analysis of phosphorylation events initiated by the cleaved activated PKC?, which would vastly extend the profound understanding of PKC?-directed signal pathways in cell death. The MS data have been deposited to the ProteomeXchange with identifier PXD000225. PMID:23879269

Xia, Li; Wang, Tong-Dan; Shen, Shao-Ming; Zhao, Meng; Sun, Han; He, Ying; Xie, Lu; Wu, Zhao-Xia; Han, San-Feng; Wang, Li-Shun; Chen, Guo-Qiang

2013-09-10

72

Genetic dissection of testis weight in mice: quantitative trait locus analysis using F 2 intercrosses between strains with extreme testis weight, and association study using Y-consomic strains  

Microsoft Academic Search

In the present study, dissection of genetic bases of testis weight in mice was performed. Autosomes and the X chromosome were\\u000a searched using traditional quantitative trait locus (QTL) scans, and the Y chromosome was searched by association studies\\u000a of Y-consomic strains. QTL analysis was performed in ?DDD × ?CBA F2 mice; the inbred mouse DDD has the heaviest testes, whereas the inbred

Jun-ichi Suto

73

Paper dissection  

NSDL National Science Digital Library

Students are provided with a dinosaur article from a popular magazine (e.g. Discover or Natural History) or the journal Science. Their task is to dissect the article distinguishing evidence from interpretation. They need to recognize the various hypotheses presented and also evaluate the strength of these ideas. Then during classroom discussion, they explore the implications of their dissections. For example they would address some of the following questions: Are other interpretations possible? Where have the authors over interpreted the evidence? What are the strongest interpretations? How could the ideas be further tested? What type of evidence would be sufficient to falsify or further support the interpretations of the papers?

Varricchio, David

74

Polyomino Dissections  

ERIC Educational Resources Information Center

|One of Gardner's passions was to introduce puzzles into the classroom. From this point of view, polyomino dissections are an excellent topic. They require little background, provide training in geometric visualization, and mostly they are fun. In this article, we put together a large collection of such puzzles, introduce a new approach in solving…

Hohn, Tiina; Liu, Andy

2012-01-01

75

Dissecting Light  

NSDL National Science Digital Library

White light is composed of the entire visible light spectrum, but how do you teach this to students in a hands-on way? The answer is simple: by using a spectroscope. This easy-to-make tool allows students to dissect light and in the process, develop an un

Proto, Christopher; Marek, Edmund A.

2000-04-01

76

Rapid Phosphoproteomic and Transcriptomic Changes in the Rhizobia-legume Symbiosis*  

PubMed Central

Symbiotic associations between legumes and rhizobia usually commence with the perception of bacterial lipochitooligosaccharides, known as Nod factors (NF), which triggers rapid cellular and molecular responses in host plants. We report here deep untargeted tandem mass spectrometry-based measurements of rapid NF-induced changes in the phosphorylation status of 13,506 phosphosites in 7739 proteins from the model legume Medicago truncatula. To place these phosphorylation changes within a biological context, quantitative phosphoproteomic and RNA measurements in wild-type plants were compared with those observed in mutants, one defective in NF perception (nfp) and one defective in downstream signal transduction events (dmi3). Our study quantified the early phosphorylation and transcription dynamics that are specifically associated with NF-signaling, confirmed a dmi3-mediated feedback loop in the pathway, and suggested “cryptic” NF-signaling pathways, some of them being also involved in the response to symbiotic arbuscular mycorrhizal fungi.

Rose, Christopher M.; Venkateshwaran, Muthusubramanian; Volkening, Jeremy D.; Grimsrud, Paul A.; Maeda, Junko; Bailey, Derek J.; Park, Kwanghyun; Howes-Podoll, Maegen; den Os, Desiree; Yeun, Li Huey; Westphall, Michael S.; Sussman, Michael R.; Ane, Jean-Michel; Coon, Joshua J.

2012-01-01

77

Clam Dissection  

NSDL National Science Digital Library

Students observe clams (Mercenaria) in a salt water aquarium, paying attention to siphons and any burrowing. They then remove the clams and describe the external morphology. The clams are then dissected, with special attention made to features (siphons, muscles) that leave observable marks on the shells. They are then provided the shells of a different genus (Mya) and asked to predict the soft tissue morphology and life mode.

Plotnick, Roy

78

Biology teachers' dissection practices and the influences that lead to their adoption: An exploratory research  

NASA Astrophysics Data System (ADS)

The lack of resolution in the on-going animal dissection debate inspired this mixed methods study to identify Connecticut secondary biology teachers' dissection practices and the influences that lead to their adoption. Qualitative findings indicate past experiences, managing objections to dissection, school culture, goals of biology teaching and ethics as major influences on dissection practices with 58.4% (n=7) of the sample dissecting and 41.6% not dissecting (n=5). Quantitative findings reveal gender, standards and curriculum, advantages of dissection and experiences as a student as major influences on dissection practices with 71.9% (n=92) of the sample dissecting and 28.1% (n=36) not dissecting. The study concludes that dissection policies are necessary and imminent in Connecticut school districts. Furthermore, it advises teacher-initiated, qualitative and quantitative assessments to expose disparities between student dissection perspectives and their own, prior to conducting dissection. Finally, it provides suggestions for addressing potential differences including administrative involvement.

Milano, Regina Nicole

79

Phosphoproteomics: searching for a needle in a haystack.  

PubMed

Most of the cellular processes are regulated by reversible phosphorylation of proteins, which in turn plays a critical role in the regulation of gene expression, cell division, signal transduction, metabolism, differentiation, and apoptosis. Mass spectrometry of phosphopeptides obtained from tryptic protein digests has become a powerful tool for characterization of phosphoproteins involved in these processes. However, there is a general need to significantly enrich the phosphopeptide content to compensate their low abundance, insufficient ionization, and suppression effects of non-phosphorylated peptides. This paper aims to give a comprehensive overview on the methods involved in recent phosphoproteomics. It presents a description of contemporary enrichment techniques with references to particular studies and compares different approaches to characterization of phosphoproteome by mass spectrometry. PMID:21839867

Tichy, Ales; Salovska, Barbora; Rehulka, Pavel; Klimentova, Jana; Vavrova, Jirina; Stulik, Jiri; Hernychova, Lenka

2011-08-04

80

InnovationsFunctional and quantitative proteomics using SILAC  

Microsoft Academic Search

Researchers in many biological areas now routinely characterize proteins by mass spectrometry. Among the many formats for quantitative proteomics, stable-isotope labelling by amino acids in cell culture (SILAC) has emerged as a simple and powerful one. SILAC removes false positives in protein-interaction studies, reveals large-scale kinetics of proteomes and — as a quantitative phosphoproteomics technology — directly uncovers important points

Matthias Mann

2006-01-01

81

Characterization of the Phosphoproteome in Human Bronchoalveolar Lavage Fluid  

PubMed Central

Global-scale examination of protein phosphorylation in human biological fluids by phosphoproteomics approaches is an emerging area of research with potential for significant contributions towards discovery of novel biomarkers. In this pilot work, we analyzed the phosphoproteome in human bronchoalveolar lavage fluid (BAL) from nondiseased subjects. The main objectives were to assess the feasibility to probe phosphorylated proteins in human BAL and to obtain the initial catalog of BAL phosphoproteins, including protein identities and exact description of their phosphorylation sites. We used a gel-free bioanalytical workflow that included whole-proteome digestion of depleted BAL proteins, enrichment of phosphopeptides by immobilized metal ion affinity chromatography (IMAC), LC-MS/MS analyses with a linear ion trap mass spectrometer, and searches of a protein sequence database to generate a panel of BAL phosphoproteins and their sites of phosphorylation. Based on sequence-diagnostic MS/MS fragmentation patterns, we identified a collection of 36 phosphopeptides that contained 26 different phosphorylation sites. These phosphopeptides mapped to 21 phosphoproteins including, for example, vimentin, plastin-2, ferritin heavy chain, kininogen-1, and others. The characterized phosphoproteins have diverse characteristics in terms of cellular origin and biological function. To the best of our knowledge, results of this study represent the first description of the human BAL phosphoproteome.

Giorgianni, Francesco; Mileo, Valentina; Desiderio, Dominic M.; Catinella, Silvia; Beranova-Giorgianni, Sarka

2012-01-01

82

Characterization of the phosphoproteome in human bronchoalveolar lavage fluid.  

PubMed

Global-scale examination of protein phosphorylation in human biological fluids by phosphoproteomics approaches is an emerging area of research with potential for significant contributions towards discovery of novel biomarkers. In this pilot work, we analyzed the phosphoproteome in human bronchoalveolar lavage fluid (BAL) from nondiseased subjects. The main objectives were to assess the feasibility to probe phosphorylated proteins in human BAL and to obtain the initial catalog of BAL phosphoproteins, including protein identities and exact description of their phosphorylation sites. We used a gel-free bioanalytical workflow that included whole-proteome digestion of depleted BAL proteins, enrichment of phosphopeptides by immobilized metal ion affinity chromatography (IMAC), LC-MS/MS analyses with a linear ion trap mass spectrometer, and searches of a protein sequence database to generate a panel of BAL phosphoproteins and their sites of phosphorylation. Based on sequence-diagnostic MS/MS fragmentation patterns, we identified a collection of 36 phosphopeptides that contained 26 different phosphorylation sites. These phosphopeptides mapped to 21 phosphoproteins including, for example, vimentin, plastin-2, ferritin heavy chain, kininogen-1, and others. The characterized phosphoproteins have diverse characteristics in terms of cellular origin and biological function. To the best of our knowledge, results of this study represent the first description of the human BAL phosphoproteome. PMID:22997577

Giorgianni, Francesco; Mileo, Valentina; Desiderio, Dominic M; Catinella, Silvia; Beranova-Giorgianni, Sarka

2012-09-11

83

Phosphoproteome exploration reveals a reformatting of cellular processes in response to low sterol biosynthetic capacity in Arabidopsis.  

PubMed

Sterols are membrane-bound isoprenoid lipids that are required for cell viability and growth. In plants, it is generally assumed that 3-hydroxy-3-methylglutaryl-CoA-reductase (HMGR) is a key element of their biosynthesis, but the molecular regulation of that pathway is largely unknown. In an attempt to identify regulators of the biosynthetic flux from acyl-CoA toward phytosterols, we compared the membrane phosphoproteome of wild-type Arabidopsis thaliana and of a mutant being deficient in HMGR1. We performed a N-terminal labeling of microsomal peptides with a trimethoxyphenyl phosphonium (TMPP) derivative, followed by a quantitative assessment of phosphopeptides with a spectral counting method. TMPP derivatization of peptides resulted in an improved LC-MS/MS detection due to increased hydrophobicity in chromatography and ionization efficiency in electrospray. The phosphoproteome coverage was 40% higher with this methodology. We further found that 31 proteins were in a different phosphorylation state in the hmgr1-1 mutant as compared with the wild-type. One-third of these proteins were identified based on novel phosphopeptides. This approach revealed that phosphorylation changes in the Arabidopsis membrane proteome targets major cellular processes such as transports, calcium homeostasis, photomorphogenesis, and carbohydrate synthesis. A reformatting of these processes appears to be a response of a genetically reduced sterol biosynthesis. PMID:22182420

Heintz, Dimitri; Gallien, Sebastien; Compagnon, Vincent; Berna, Anne; Suzuki, Masashi; Yoshida, Shigeo; Muranaka, Toshiya; Van Dorsselaer, Alain; Schaeffer, Christine; Bach, Thomas J; Schaller, Hubert

2012-01-11

84

Systematic Analysis of Protein Phosphorylation Networks From Phosphoproteomic Data*  

PubMed Central

In eukaryotes, hundreds of protein kinases (PKs) specifically and precisely modify thousands of substrates at specific amino acid residues to faithfully orchestrate numerous biological processes, and reversibly determine the cellular dynamics and plasticity. Although over 100,000 phosphorylation sites (p-sites) have been experimentally identified from phosphoproteomic studies, the regulatory PKs for most of these sites still remain to be characterized. Here, we present a novel software package of iGPS for the prediction of in vivo site-specific kinase-substrate relations mainly from the phosphoproteomic data. By critical evaluations and comparisons, the performance of iGPS is satisfying and better than other existed tools. Based on the prediction results, we modeled protein phosphorylation networks and observed that the eukaryotic phospho-regulation is poorly conserved at the site and substrate levels. With an integrative procedure, we conducted a large-scale phosphorylation analysis of human liver and experimentally identified 9719 p-sites in 2998 proteins. Using iGPS, we predicted a human liver protein phosphorylation networks containing 12,819 potential site-specific kinase-substrate relations among 350 PKs and 962 substrates for 2633 p-sites. Further statistical analysis and comparison revealed that 127 PKs significantly modify more or fewer p-sites in the liver protein phosphorylation networks against the whole human protein phosphorylation network. The largest data set of the human liver phosphoproteome together with computational analyses can be useful for further experimental consideration. This work contributes to the understanding of phosphorylation mechanisms at the systemic level, and provides a powerful methodology for the general analysis of in vivo post-translational modifications regulating sub-proteomes.

Song, Chunxia; Ye, Mingliang; Liu, Zexian; Cheng, Han; Jiang, Xinning; Han, Guanghui; Songyang, Zhou; Tan, Yexiong; Wang, Hongyang; Ren, Jian; Xue, Yu; Zou, Hanfa

2012-01-01

85

Phosphoproteomic biomarkers predicting histologic nonalcoholic steatohepatitis and fibrosis.  

PubMed

The progression of nonalcoholic fatty liver disease (NAFLD) has been linked to deregulated exchange of the endocrine signaling between adipose and liver tissue. Proteomic assays for the phosphorylation events that characterize the activated or deactivated state of the kinase-driven signaling cascades in visceral adipose tissue (VAT) could shed light on the pathogenesis of nonalcoholic steatohepatitis (NASH) and related fibrosis. Reverse-phase protein microarrays (RPMA) were used to develop biomarkers for NASH and fibrosis using VAT collected from 167 NAFLD patients (training cohort, N = 117; testing cohort, N = 50). Three types of models were developed for NASH and advanced fibrosis: clinical models, proteomics models, and combination models. NASH was predicted by a model that included measurements of two components of the insulin signaling pathway: AKT kinase and insulin receptor substrate 1 (IRS1). The models for fibrosis were less reliable when predictions were based on phosphoproteomic, clinical, or the combination data. The best performing model relied on levels of the phosphorylation of GSK3 as well as on two subunits of cyclic AMP regulated protein kinase A (PKA). Phosphoproteomics technology could potentially be used to provide pathogenic information about NASH and NASH-related fibrosis. This information can lead to a clinically relevant diagnostic/prognostic biomarker for NASH. PMID:20441224

Younossi, Zobair M; Baranova, Ancha; Stepanova, Maria; Page, Sandra; Calvert, Valerie S; Afendy, Arian; Goodman, Zachary; Chandhoke, Vikas; Liotta, Lance; Petricoin, Emanuel

2010-06-01

86

Integrative Features of the Yeast Phosphoproteome and Protein–Protein Interaction Map  

Microsoft Academic Search

Following recent advances in high-throughput mass spectrometry (MS)–based proteomics, the numbers of identified phosphoproteins and their phosphosites have greatly increased in a wide variety of organisms. Although a critical role of phosphorylation is control of protein signaling, our understanding of the phosphoproteome remains limited. Here, we report unexpected, large-scale connections revealed between the phosphoproteome and protein interactome by integrative data-mining

Nozomu Yachie; Rintaro Saito; Naoyuki Sugiyama; Masaru Tomita; Yasushi Ishihama

2011-01-01

87

Comparative phosphoproteomics reveals evolutionary and functional conservation of phosphorylation across eukaryotes  

PubMed Central

Background Reversible phosphorylation of proteins is involved in a wide range of processes, ranging from signaling cascades to regulation of protein complex assembly. Little is known about the structure and evolution of phosphorylation networks. Recent high-throughput phosphoproteomics studies have resulted in the rapid accumulation of phosphopeptide datasets for many model organisms. Here, we exploit these novel data for the comparative analysis of phosphorylation events between different species of eukaryotes. Results Comparison of phosphoproteomics datasets of six eukaryotes yields an overlap ranging from approximately 700 sites for human and mouse (two large datasets of closely related species) to a single site for fish and yeast (distantly related as well as two of the smallest datasets). Some conserved events appear surprisingly old; those shared by plant and animals suggest conservation over the time scale of a billion years. In spite of the hypothesized incomprehensive nature of phosphoproteomics datasets and differences in experimental procedures, we show that the overlap between phosphoproteomes is greater than expected by chance and indicates increased functional relevance. Despite the dynamic nature of the evolution of phosphorylation, the relative overlap between the different datasets is identical to the phylogeny of the species studied. Conclusion This analysis provides a framework for the generation of biological insights by comparative analysis of high-throughput phosphoproteomics datasets. We expect the rapidly growing body of data from high-throughput mass spectrometry analysis to make comparative phosphoproteomics a powerful tool for elucidating the evolutionary and functional dynamics of reversible phosphorylation.

Boekhorst, Jos; van Breukelen, Bas; Heck, Albert JR; Snel, Berend

2008-01-01

88

Phosphoproteome Dynamics Upon Changes in Plant Water Status Reveal Early Events Associated With Rapid Growth Adjustment in Maize Leaves*  

PubMed Central

Plant growth adjustment during water deficit is a crucial adaptive response. The rapid fine-tuned control achieved at the post-translational level is believed to be of considerable importance for regulating early changes in plant growth reprogramming. Aiming at a better understanding of early responses to contrasting plant water statuses, we carried out a survey of the protein phosphorylation events in the growing zone of maize leaves upon a range of water regimes. In this study, the impact of mild and severe water deficits were evaluated in comparison with constant optimal watering and with recovery periods lasting 5, 10, 20, 30, 45, and 60 min. Using four biological replicates per treatment and a robust quantitative phosphoproteomic methodology based on stable-isotope labeling, we identified 3664 unique phosphorylation sites on 2496 proteins. The abundance of nearly 1250 phosphorylated peptides was reproducibly quantified and profiled with high confidence among treatments. A total of 138 phosphopeptides displayed highly significant changes according to water regimes and enabled to identify specific patterns of response to changing plant water statuses. Further quantification of protein amounts emphasized that most phosphorylation changes did not reflect protein abundance variation. During water deficit and recovery, extensive changes in phosphorylation status occurred in critical regulators directly or indirectly involved in plant growth and development. These included proteins influencing epigenetic control, gene expression, cell cycle-dependent processes and phytohormone-mediated responses. Some of the changes depended on stress intensity whereas others depended on rehydration duration, including rapid recoveries that occurred as early as 5 or 10 mins after rewatering. By combining a physiological approach and a quantitative phosphoproteomic analysis, this work provides new insights into the in vivo early phosphorylation events triggered by rapid changes in plant water status, and their possible involvement in plant growth-related processes.

Bonhomme, Ludovic; Valot, Benoit; Tardieu, Francois; Zivy, Michel

2012-01-01

89

Marquette University Neuroanatomical Dissection  

NSDL National Science Digital Library

This website provides information regarding Marquette University' Neuroanatomical Dissection Summer Course. The focus of the course is an intensive review of the brain and spinal cord. Participants will spend a portion of the course dissecting a cadaver.

Marquette University (Marquette University)

2012-07-24

90

Phosphoproteomic analysis reveals interconnected system-wide responses to perturbations of kinases and phosphatases in yeast.  

PubMed

The phosphorylation and dephosphorylation of proteins by kinases and phosphatases constitute an essential regulatory network in eukaryotic cells. This network supports the flow of information from sensors through signaling systems to effector molecules and ultimately drives the phenotype and function of cells, tissues, and organisms. Dysregulation of this process has severe consequences and is one of the main factors in the emergence and progression of diseases, including cancer. Thus, major efforts have been invested in developing specific inhibitors that modulate the activity of individual kinases or phosphatases; however, it has been difficult to assess how such pharmacological interventions would affect the cellular signaling network as a whole. Here, we used label-free, quantitative phosphoproteomics in a systematically perturbed model organism (Saccharomyces cerevisiae) to determine the relationships between 97 kinases, 27 phosphatases, and more than 1000 phosphoproteins. We identified 8814 regulated phosphorylation events, describing the first system-wide protein phosphorylation network in vivo. Our results show that, at steady state, inactivation of most kinases and phosphatases affected large parts of the phosphorylation-modulated signal transduction machinery-and not only the immediate downstream targets. The observed cellular growth phenotype was often well maintained despite the perturbations, arguing for considerable robustness in the system. Our results serve to constrain future models of cellular signaling and reinforce the idea that simple linear representations of signaling pathways might be insufficient for drug development and for describing organismal homeostasis. PMID:21177495

Bodenmiller, Bernd; Wanka, Stefanie; Kraft, Claudine; Urban, Jörg; Campbell, David; Pedrioli, Patrick G; Gerrits, Bertran; Picotti, Paola; Lam, Henry; Vitek, Olga; Brusniak, Mi-Youn; Roschitzki, Bernd; Zhang, Chao; Shokat, Kevan M; Schlapbach, Ralph; Colman-Lerner, Alejandro; Nolan, Garry P; Nesvizhskii, Alexey I; Peter, Matthias; Loewith, Robbie; von Mering, Christian; Aebersold, Ruedi

2010-12-21

91

The Problems of Dissection.  

ERIC Educational Resources Information Center

|Describes some problems of classroom dissection including the cruelty that animals destined for the laboratory suffer. Discusses the multilevel approach that the National Anti-Vivisection Society (NAVS) has developed to address the problems of animal dissection such as offering a dissection hotline, exhibiting at science teacher conferences, and…

Davis, Pat

1997-01-01

92

Genetic dissection of tocopherol and phytosterol in recombinant inbred lines of sunflower through quantitative trait locus analysis and the candidate gene approach  

Microsoft Academic Search

Sunflower (Helianthus annuus L.) contains tocopherol, a non-enzymatic antioxidant known as lipid-soluble vitamin E, and phytosterol, with interesting\\u000a properties, which can result in decreased risk of chronic diseases in humans and with several beneficial effects in plants.\\u000a The genetic control of tocopherol and phytosterol content in a population of 123 recombinant inbred lines of sunflower was\\u000a studied through quantitative trait

P. Haddadi; A. Ebrahimi; N. B. Langlade; B. Yazdi-samadi; M. Berger; A. Calmon; M. R. Naghavi; P. Vincourt; A. Sarrafi

93

Proteome and phosphoproteome of Africanized and European honeybee venoms.  

PubMed

Honey bee venom toxins trigger immunological, physiological, and neurological responses within victims. The high occurrence of bee attacks involving potentially fatal toxic and allergic reactions in humans and the prospect of developing novel pharmaceuticals make honey bee venom an attractive target for proteomic studies. Using label-free quantification, we compared the proteome and phosphoproteome of the venom of Africanized honeybees with that of two European subspecies, namely Apis mellifera ligustica and A. m. carnica. From the total of 51 proteins, 42 were common to all three subspecies. Remarkably, the toxins melittin and icarapin were phosphorylated. In all venoms, icarapin was phosphorylated at the (205) Ser residue, which is located in close proximity to its known antigenic site. Melittin, the major toxin of honeybee venoms, was phosphorylated in all venoms at the (10) Thr and (18) Ser residues. (18) Ser phosphorylated melittin-the major of its two phosphorylated forms-was less toxic compared to the native peptide. PMID:23798553

Resende, Virgínia Maria Ferreira; Vasilj, Andrej; Santos, Keity Souza; Palma, Mario Sergio; Shevchenko, Andrej

2013-09-01

94

Cocaine and aortic dissection.  

PubMed

Aortic dissection is a rare, potentially catastrophic vascular emergency. Early recognition of the clinical manifestations, rapid confirmation using imaging modalities, urgent administration of appropriate medication and expedient selection of definitive long-term therapy are key to preserving life and reducing morbidity. In recent years it has become increasingly clear that there is a relation between cocaine and aortic dissection. Cocaine serves as both a predisposing factor to aortic dissection due to its effect on aortic connective tissue and as a precipitating factor due to its propensity to produce abrupt and severe hypertension. While similarities exist in the clinical features and diagnostic methods between cocaine-related aortic dissection and aortic dissection unrelated to cocaine use, there are important differences in management between these two syndromes which are rooted in the pharmacology and physiology of cocaine. An understanding of these differences is key to effective early and long-term management of cocaine-related aortic dissection. PMID:20233907

Singh, Avneet; Khaja, Azamuddin; Alpert, Martin A

2010-04-01

95

Cellular Quantitative Structure-Activity Relationship (Cell-QSAR): Conceptual Dissection of Receptor Binding and Intracellular Disposition in Antifilarial Activities of Selwood Antimycins  

PubMed Central

We present the cellular quantitative structure–activity relationship (cell-QSAR) concept that adapts ligand-based and receptor-based 3D-QSAR methods for use with cell-level activities. The unknown intracellular drug disposition is accounted for by the disposition function (DF), a model-based, nonlinear function of a drug’s lipophilicity, acidity, and other properties. We conceptually combined the DF with our multispecies, multimode version of the frequently used ligand-based comparative molecular field analysis (CoMFA) method, forming a single correlation function for fitting the cell-level activities. The resulting cell-QSAR model was applied to the Selwood data on filaricidal activities of antimycin analogues. Their molecules are flexible, ionize under physiologic conditions, form different intramolecular H-bonds for neutral and ionized species, and cross several membranes to reach unknown receptors. The calibrated cell-QSAR model is significantly more predictive than other models lacking the disposition part and provides valuable structure optimization clues by factorizing the cell-level activity of each compound into the contributions of the receptor binding and disposition.

2012-01-01

96

Cellular quantitative structure-activity relationship (Cell-QSAR): conceptual dissection of receptor binding and intracellular disposition in antifilarial activities of Selwood antimycins.  

PubMed

We present the cellular quantitative structure-activity relationship (cell-QSAR) concept that adapts ligand-based and receptor-based 3D-QSAR methods for use with cell-level activities. The unknown intracellular drug disposition is accounted for by the disposition function (DF), a model-based, nonlinear function of a drug's lipophilicity, acidity, and other properties. We conceptually combined the DF with our multispecies, multimode version of the frequently used ligand-based comparative molecular field analysis (CoMFA) method, forming a single correlation function for fitting the cell-level activities. The resulting cell-QSAR model was applied to the Selwood data on filaricidal activities of antimycin analogues. Their molecules are flexible, ionize under physiologic conditions, form different intramolecular H-bonds for neutral and ionized species, and cross several membranes to reach unknown receptors. The calibrated cell-QSAR model is significantly more predictive than other models lacking the disposition part and provides valuable structure optimization clues by factorizing the cell-level activity of each compound into the contributions of the receptor binding and disposition. PMID:22468611

Natesan, Senthil; Wang, Tiansheng; Lukacova, Viera; Bartus, Vladimir; Khandelwal, Akash; Subramaniam, Rajesh; Balaz, Stefan

2012-04-11

97

Using SNP markers to dissect linkage disequilibrium at a major quantitative trait locus for resistance to the potato cyst nematode Globodera pallida on potato chromosome V.  

PubMed

The damage caused by the parasitic root cyst nematode Globodera pallida is a major yield-limiting factor in potato cultivation . Breeding for resistance is facilitated by the PCR-based marker 'HC', which is diagnostic for an allele conferring high resistance against G. pallida pathotype Pa2/3 that has been introgressed from the wild potato species Solanum vernei into the Solanum tuberosum tetraploid breeding pool. The major quantitative trait locus (QTL) controlling this nematode resistance maps on potato chromosome V in a hot spot for resistance to various pathogens including nematodes and the oomycete Phytophthora infestans. An unstructured sample of 79 tetraploid, highly heterozygous varieties and breeding clones was selected based on presence (41 genotypes) or absence (38 genotypes) of the HC marker. Testing the clones for resistance to G. pallida confirmed the diagnostic power of the HC marker. The 79 individuals were genotyped for 100 single nucleotide polymorphisms (SNPs) at 10 loci distributed over 38 cM on chromosome V. Forty-five SNPs at six loci spanning 2 cM in the interval between markers GP21-GP179 were associated with resistance to G. pallida. Based on linkage disequilibrium (LD) between SNP markers, six LD groups comprising between 2 and 18 SNPs were identified. The LD groups indicated the existence of multiple alleles at a single resistance locus or at several, physically linked resistance loci. LD group C comprising 18 SNPs corresponded to the 'HC' marker. LD group E included 16 SNPs and showed an association peak, which positioned one nematode resistance locus physically close to the R1 gene family. PMID:19020852

Achenbach, Ute; Paulo, Joao; Ilarionova, Evgenyia; Lübeck, Jens; Strahwald, Josef; Tacke, Eckhard; Hofferbert, Hans-Reinhard; Gebhardt, Christiane

2008-11-20

98

Genetic Dissection of Quantitative Trait Loci for Hemostasis and Thrombosis on Mouse Chromosomes 11 and 5 Using Congenic and Subcongenic Strains  

PubMed Central

Susceptibility to thrombosis varies in human populations as well as many inbred mouse strains. Only a small portion of this variation has been identified, suggesting that there are unknown modifier genes. The objective of this study was to narrow the quantitative trait locus (QTL) intervals previously identified for hemostasis and thrombosis on mouse distal chromosome 11 (Hmtb6) and on chromosome 5 (Hmtb4 and Hmtb5). In a tail bleeding/rebleeding assay, a reporter assay for hemostasis and thrombosis, subcongenic strain (6A-2) had longer clot stability time than did C57BL/6J (B6) mice but a similar time to the B6-Chr11A/J consomic mice, confirming the Hmtb6 phenotype. Six congenic and subcongenic strains were constructed for chromosome 5, and the congenic strain, 2A-1, containing the shortest A/J interval (16.6 cM, 26.6 Mbp) in the Hmtb4 region, had prolonged clot stability time compared to B6 mice. In the 3A-2 and CSS-5 mice bleeding time was shorter than for B6, mice confirming the Hmtb5 QTL. An increase in bleeding time was identified in another congenic strain (3A-1) with A/J interval (24.8 cM, 32.9 Mbp) in the proximal region of chromosome 5, confirming a QTL for bleeding previously mapped to that region and designated as Hmtb10. The subcongenic strain 4A-2 with the A/J fragment in the proximal region had a long occlusion time of the carotid artery after ferric chloride injury and reduced dilation after injury to the abdominal aorta compared to B6 mice, suggesting an additional locus in the proximal region, which was designated Hmtb11 (5 cM, 21.4 Mbp). CSS-17 mice crossed with congenic strains, 3A-1 and 3A-2, modified tail bleeding. Using congenic and subcongenic analysis, candidate genes previously identified and novel genes were identified as modifiers of hemostasis and thrombosis in each of the loci Hmtb6, Hmtb4, Hmtb10, and Hmtb11.

Hoover-Plow, Jane; Sa, Qila; Huang, Menggui; Grondolsky, Jessica

2013-01-01

99

Genetic dissection of quantitative trait Loci for hemostasis and thrombosis on mouse chromosomes 11 and 5 using congenic and subcongenic strains.  

PubMed

Susceptibility to thrombosis varies in human populations as well as many inbred mouse strains. Only a small portion of this variation has been identified, suggesting that there are unknown modifier genes. The objective of this study was to narrow the quantitative trait locus (QTL) intervals previously identified for hemostasis and thrombosis on mouse distal chromosome 11 (Hmtb6) and on chromosome 5 (Hmtb4 and Hmtb5). In a tail bleeding/rebleeding assay, a reporter assay for hemostasis and thrombosis, subcongenic strain (6A-2) had longer clot stability time than did C57BL/6J (B6) mice but a similar time to the B6-Chr11(A/J) consomic mice, confirming the Hmtb6 phenotype. Six congenic and subcongenic strains were constructed for chromosome 5, and the congenic strain, 2A-1, containing the shortest A/J interval (16.6 cM, 26.6 Mbp) in the Hmtb4 region, had prolonged clot stability time compared to B6 mice. In the 3A-2 and CSS-5 mice bleeding time was shorter than for B6, mice confirming the Hmtb5 QTL. An increase in bleeding time was identified in another congenic strain (3A-1) with A/J interval (24.8 cM, 32.9 Mbp) in the proximal region of chromosome 5, confirming a QTL for bleeding previously mapped to that region and designated as Hmtb10. The subcongenic strain 4A-2 with the A/J fragment in the proximal region had a long occlusion time of the carotid artery after ferric chloride injury and reduced dilation after injury to the abdominal aorta compared to B6 mice, suggesting an additional locus in the proximal region, which was designated Hmtb11 (5 cM, 21.4 Mbp). CSS-17 mice crossed with congenic strains, 3A-1 and 3A-2, modified tail bleeding. Using congenic and subcongenic analysis, candidate genes previously identified and novel genes were identified as modifiers of hemostasis and thrombosis in each of the loci Hmtb6, Hmtb4, Hmtb10, and Hmtb11. PMID:24147020

Hoover-Plow, Jane; Sa, Qila; Huang, Menggui; Grondolsky, Jessica

2013-10-17

100

Flower Dissection Lab  

NSDL National Science Digital Library

From Fairchild Tropical Botanic Garden, this site presents a simple Flower Dissection Lab using orchids and composite flowers. This pdf document contains the materials needed and instructions for the lab, as well as a worksheet for students to complete as they dissect their flower.

2007-12-27

101

Early phosphoproteomic changes in the mouse spleen during deoxynivalenol-induced ribotoxic stress.  

PubMed

The trichothecene mycotoxin deoxynivalenol (DON) targets the innate immune system and is of public health significance because of its frequent presence in human and animal food. DON-induced proinflammatory gene expression and apoptosis in the lymphoid tissue have been associated with a ribotoxic stress response (RSR) that involves rapid phosphorylation of mitogen-activated protein kinases (MAPKs). To better understand the relationship between protein phosphorylation and DON's immunotoxic effects, stable isotope dimethyl labeling-based proteomics in conjunction with titanium dioxide chromatography was employed to quantitatively profile the immediate (? 30min) phosphoproteome changes in the spleens of mice orally exposed to 5mg/kg body weight DON. A total of 90 phosphoproteins indicative of novel phosphorylation events were significantly modulated by DON. In addition to critical branches and scaffolds of MAPK signaling being affected, DON exposure also altered phosphorylation of proteins that mediate phosphatidylinositol 3-kinase/AKT pathways. Gene ontology analysis revealed that DON exposure affected biological processes such as cytoskeleton organization, regulation of apoptosis, and lymphocyte activation and development, which likely contribute to immune dysregulation associated with DON-induced RSR. Consistent with these findings, DON impacted phosphorylation of proteins within diverse immune cell populations, including monocytes, macrophages, T cells, B cells, dendritic cells, and mast cells. Fuzzy c-means clustering analysis further indicated that DON evoked several distinctive temporal profiles of regulated phosphopeptides. Overall, the findings from this investigation can serve as a template for future focused exploration and modeling of cellular responses associated with the immunotoxicity evoked by DON and other ribotoxins. PMID:23811945

Pan, Xiao; Whitten, Douglas A; Wu, Ming; Chan, Christina; Wilkerson, Curtis G; Pestka, James J

2013-06-29

102

A Pipeline for (15)N Metabolic Labeling and Phosphoproteome Analysis in Arabidopsis thaliana.  

PubMed

Within the past two decades, the biological application of mass spectrometric technology has seen great advances in terms of innovations in hardware, software, and reagents. Concurrently, the burgeoning field of proteomics has followed closely (Yates et al., Annu Rev Biomed Eng 11:49-79, 2009)-and with it, importantly, the ability to globally assay altered levels of posttranslational modifications in response to a variety of stimuli. Though many posttranslational modifications have been described, a major focus of these efforts has been protein-level phosphorylation of serine, threonine, and tyrosine residues (Schreiber et al., Proteomics 8:4416-4432, 2008). The desire to examine changes across signal transduction cascades and networks in their entirety using a single mass spectrometric analysis accounts for this push-namely, preservation and enrichment of the transient yet informative phosphoryl side group. Analyzing global changes in phosphorylation allows inferences surrounding cascades/networks as a whole to be made. Towards this same end, much work has explored ways to permit quantitation and combine experimental samples such that more than one replicate or experimental condition can be identically processed and analyzed, cutting down on experimental and instrument variability, in addition to instrument run time. One such technique that has emerged is metabolic labeling (Gouw et al., Mol Cell Proteomics 9:11-24, 2010), wherein biological samples are labeled in living cells with nonradioactive heavy isotopes such as (15)N or (13)C. Since metabolic labeling in living organisms allows one to combine the material to be processed at the earliest possible step, before the tissue is homogenized, it provides a unique and excellent method for comparing experimental samples in a high-throughput, reproducible fashion with minimal technical variability. This chapter describes a pipeline used for labeling living Arabidopsis thaliana plants with nitrogen-15 ((15)N) and how this can be used, in conjunction with a technique for enrichment of phosphorylated peptides (phosphopeptides), to determine changes in A. thaliana's phosphoproteome on an untargeted, global scale. PMID:24057376

Minkoff, Benjamin B; Burch, Heather L; Sussman, Michael R

2014-01-01

103

Postpartum aortic dissection.  

PubMed

Postpartum aortic dissection is a rare but lethal event. Until now, only a limited number of cases have been reported, and a comprehensive literature review from 1988 to 2012 yielded 27 cases. Postpartum aortic dissection occurred between Day 1 and Day 42 after delivery, either vaginally or by cesarean section. Pregnancy alone without underlying contributing risk factors and Marfan syndrome were the two main risk factors for postpartum aortic dissection, accounting for 44.4% and 40.7% of cases, respectively. Late presentation and delayed diagnosis may lead to sudden death. Improving prenatal and peripartum care is, therefore, crucial in preventing the development of aortic dissection. Prompt diagnosis and timely treatment of postpartum aortic dissection may prevent patient death. PMID:24075366

Yuan, Shi-Min

2013-09-01

104

Renal artery dissection.  

PubMed Central

Renal artery dissections are stenotic or occlusive lesions most often observed in hypertensive patients with underlying atherosclerosis or fibromuscular disease. Acute dissections may present spontaneously, as a complication of diagnostic or therapeutic angiography or as an agonal event associated with overwhelming systemic illness. Chronic dissections may produce renovascular hypertension or be entirely asymptomatic. Fourteen renal artery dissections have been encountered in nine patients treated at Vanderbilt University Medical Center during the past decade. Eleven dissections have been found in seven patients with renovascular hypertension. Seven of these dissections were chronic (six functional, one silent) and four acute (two spontaneous, two secondary to angiography). Three agonal dissections were found in two additional patients postmortem: one at autopsy and bilateral dissections found at the time of cadaveric donor nephrectomy. Ten bypass procedures, including five complex branch reconstructions of which three were performed ex vivo, have been performed with 100% immediate patency and maintenance or improvement of renal function. Long-term follow-up of these patients has shown sustained patency of the reconstructed renal arteries, excellent blood pressure control, and normal renal function in all. Nephrectomy has not been required and there have been no associated deaths. Seventy-seven additional renal artery dissections in 72 patients collected from previous reports have been analyzed. Patient survival (55/72, 76.4%) and preservation of the involved kidney in surviving patients (26/55, 47.3%) were low in these earlier series. In addition, renal failure was associated with 59% of the deaths. The lethality of renal artery dissections and the ease and success of revascularization, which preserves renal function and ameliorates associated renovascular hypertension, emphasize the need for an aggressive approach to the recognition and treatment of this entity. Therapy should be directed toward arterial reconstructions and the preservation of functioning renal tissue. Images FIG. 1A. FIG. 2A. FIG. 5. FIG. 6. FIG. 7. FIG. 9. FIG. 10. FIG. 11.

Smith, B M; Holcomb, G W; Richie, R E; Dean, R H

1984-01-01

105

Phospho-Proteomic Screen Identifies Potential Therapeutic Targets in Melanoma  

PubMed Central

Therapies directed against receptor tyrosine kinases are effective in many cancer subtypes, including lung and breast cancer. We used a phospho-proteomic platform to identify active receptor tyrosine kinases that might represent therapeutic targets in a panel of twenty-five melanoma cell strains. We detected activated receptors including TYRO3, AXL, MERTK, EPHB2, MET, IGF1R, EGFR, KIT, HER3, and HER4. Statistical analysis of receptor tyrosine kinase activation as well as ligand and receptor expression indicates that some receptors, such as FGFR3, may be activated via autocrine circuits. shRNA knockdown targeting three of the active kinases identified in the screen, AXL, HER3, and IGF1R, inhibited the proliferation of melanoma cells and knockdown of active AXL also reduced melanoma cell migration. The changes in cellular phenotype observed upon AXL knockdown appear to be modulated via the STAT3 signaling pathway, while the IGF1R-dependent alterations seem to be regulated by the AKT signaling pathway. Ultimately, this study identifies several novel targets for therapeutic intervention in melanoma.

Tworkoski, Kathryn; Singhal, Garima; Szpakowski, Sebastian; Zito, Christina Ivins; Bacchiocchi, Antonella; Muthusamy, Viswanathan; Bosenberg, Marcus; Krauthammer, Michael; Halaban, Ruth; Stern, David F.

2011-01-01

106

Global kinomic and phospho-proteomic analyses of the human malaria parasite Plasmodium falciparum  

Microsoft Academic Search

The role of protein phosphorylation in the life cycle of malaria parasites is slowly emerging. Here we combine global phospho-proteomic analysis with kinome-wide reverse genetics to assess the importance of protein phosphorylation in Plasmodium falciparum asexual proliferation. We identify 1177 phosphorylation sites on 650 parasite proteins that are involved in a wide range of general cellular activities such as DNA

Lev Solyakov; Jean Halbert; Mahmood M. Alam; Jean-Philippe Semblat; Dominique Dorin-Semblat; Luc Reininger; Andrew R. Bottrill; Sharad Mistry; Abdirhaman Abdi; Clare Fennell; Zoe Holland; Claudia Demarta; Yvan Bouza; Audrey Sicard; Marie-Paule Nivez; Sylvain Eschenlauer; Tenzing Lama; Divya Catherine Thomas; Pushkar Sharma; Shruti Agarwal; Selina Kern; Gabriele Pradel; Michele Graciotti; Andrew B. Tobin; Christian Doerig

2011-01-01

107

Chemical phosphoproteomics and development of bisubstrate based inhibitors of protein kinase C isozymes  

Microsoft Academic Search

Protein phosphorylation is one of the most abundant post-translational modifications. Phosphorylation is important for the function of the protein, for example it regulates enzyme activity, signal transduction and cell division. Protein phosphorylation plays a central role in virtually all crucial cellular processes. Therefore methods have been developed to determine which proteins are phosphorylated, that is to unravel the phosphoproteome. One

A. J. Poot

2010-01-01

108

Traumatic carotid artery dissection.  

PubMed

Traumatic carotid artery dissections are uncommon and potentially devastating injuries that often have a delayed presentation. Soldiers often engage in leisure, training, and combat activities that place them at risk for sustaining an injury that causes a carotid artery dissection. To compound matters, spontaneous dissections are being more frequently recognized as well. Clinicians must be thorough in their history taking and maintain an elevated level of suspicion for this injury when presented with neurologic symptoms suggestive of head and neck pathology. This case study illustrates the difficulties encountered in arriving at a timely, correct diagnosis and offers treatment plan options. We hope that this case study will facilitate the early recognition and treatment of carotid artery dissections in the future. PMID:23764161

Hostettler, Cathy; Williams, Thomas; McKnight, Christine; Sanchez, Angela; Diggs, Georgette

2013-01-01

109

Carotid dissection (image)  

MedlinePLUS

... obstruction, or leak in the lining of the carotid. This leaking of blood into the artery wall ( ... to the neck, which means stroke secondary to carotid dissection may occur in young people as well ...

110

Wrangling Phosphoproteomic Data to Elucidate Cancer Signaling Pathways  

PubMed Central

The interpretation of biological data sets is essential for generating hypotheses that guide research, yet modern methods of global analysis challenge our ability to discern meaningful patterns and then convey results in a way that can be easily appreciated. Proteomic data is especially challenging because mass spectrometry detectors often miss peptides in complex samples, resulting in sparsely populated data sets. Using the R programming language and techniques from the field of pattern recognition, we have devised methods to resolve and evaluate clusters of proteins related by their pattern of expression in different samples in proteomic data sets. We examined tyrosine phosphoproteomic data from lung cancer samples. We calculated dissimilarities between the proteins based on Pearson or Spearman correlations and on Euclidean distances, whilst dealing with large amounts of missing data. The dissimilarities were then used as feature vectors in clustering and visualization algorithms. The quality of the clusterings and visualizations were evaluated internally based on the primary data and externally based on gene ontology and protein interaction networks. The results show that t-distributed stochastic neighbor embedding (t-SNE) followed by minimum spanning tree methods groups sparse proteomic data into meaningful clusters more effectively than other methods such as k-means and classical multidimensional scaling. Furthermore, our results show that using a combination of Spearman correlation and Euclidean distance as a dissimilarity representation increases the resolution of clusters. Our analyses show that many clusters contain one or more tyrosine kinases and include known effectors as well as proteins with no known interactions. Visualizing these clusters as networks elucidated previously unknown tyrosine kinase signal transduction pathways that drive cancer. Our approach can be applied to other data types, and can be easily adopted because open source software packages are employed.

Grimes, Mark L.; Lee, Wan-Jui; van der Maaten, Laurens; Shannon, Paul

2013-01-01

111

The Rapamycin-sensitive Phosphoproteome Reveals That TOR Controls Protein Kinase A Toward Some But Not All Substrates  

PubMed Central

Regulation of cell growth requires extensive coordination of several processes including transcription, ribosome biogenesis, translation, nutrient metabolism, and autophagy. In yeast, the protein kinases Target of Rapamycin (TOR) and protein kinase A (PKA) regulate these processes and are thereby the main activators of cell growth in response to nutrients. How TOR, PKA, and their corresponding signaling pathways are coordinated to control the same cellular processes is not understood. Quantitative analysis of the rapamycin-sensitive phosphoproteome combined with targeted analysis of PKA substrates suggests that TOR complex 1 (TORC1) activates PKA but only toward a subset of substrates. Furthermore, we show that TORC1 signaling impinges on BCY1, the negative regulatory subunit of PKA. Inhibition of TORC1 with rapamycin leads to BCY1 phosphorylation on several sites including T129. Phosphorylation of BCY1 T129 results in BCY1 activation and inhibition of PKA. TORC1 inhibits BCY1 T129 phosphorylation by phosphorylating and activating the S6K homolog SCH9 that in turn inhibits the MAP kinase MPK1. MPK1 phosphorylates BCY1 T129 directly. Thus, TORC1 activates PKA toward some substrates by preventing MPK1-mediated activation of BCY1.

Soulard, Alexandre; Cremonesi, Alessio; Moes, Suzette; Schutz, Frederic; Jeno, Paul

2010-01-01

112

Posttranslational regulation of self-renewal capacity: insights from proteome and phosphoproteome analyses of stem cell leukemia.  

PubMed

We recently generated 2 phenotypically similar Hoxa9+Meis1 overexpressing acute myeloid leukemias that differ by their in vivo biologic behavior. The first leukemia, named FLA2, shows a high frequency of leukemia stem cells (LSCs; 1 in 1.4 cells), whereas the second, FLB1, is more typical with a frequency of LSCs in the range of 1 per several hundred cells. To gain insights into possible mechanisms that determine LSC self-renewal, we profiled and compared the abundance of nuclear and cytoplasmic proteins and phosphoproteins from these leukemias using quantitative proteomics. These analyses revealed differences in proteins associated with stem cell fate, including a hyperactive p38 MAP kinase in FLB1 and a differentially localized Polycomb group protein Ezh2, which is mostly nuclear in FLA2 and predominantly cytoplasmic in FLB1. Together, these newly documented proteomes and phosphoproteomes represent a unique resource with more than 440 differentially expressed proteins and 11 543 unique phosphopeptides, of which 80% are novel and 7% preferentially phosphorylated in the stem cell-enriched leukemia. PMID:22802335

Trost, Matthias; Sauvageau, Martin; Hérault, Olivier; Deleris, Paul; Pomiès, Christelle; Chagraoui, Jalila; Mayotte, Nadine; Meloche, Sylvain; Sauvageau, Guy; Thibault, Pierre

2012-07-16

113

Chemical tagging strategies for mass spectrometry-based phospho-proteomics.  

PubMed

The study of protein phosphorylation in combination with chemical methods may serve several purposes. The removal of the phosphate group from phosphoserine and -threonine residues by beta-elimination has been employed to improve sensitivity for mass spectrometric detection and to attach affinity tags for phosphopeptide enrichment. More recently, phosphoramidate chemistry has been shown to be another promising tool for enriching phosphorylated peptides, and other phosphate-directed reactions may also be applicable to the study of the phosphoproteome in the future. In recent years, the combination of large-scale phospho-proteomics studies with stable isotope labeling for quantification purposes has become of growing importance, frequently involving the introduction of chemical tags such as iTRAQ. In this chapter, we will highlight several key strategies that involve chemical tagging reactions. PMID:19241017

Leitner, Alexander; Lindner, Wolfgang

2009-01-01

114

Cadaver preservation and dissection  

Microsoft Academic Search

Postgraduate cadaver dissection is an unsurpassed method of maintaining and improving one's knowledge of anatomy. Since fresh cadavers are not always available, some form of preservation is often required especially for courses or workshops. A technique using glutaraldehyde is described and its pros and cons compared with the time honored formaldehyde-phenol technique. The method is particularly suitable for cadaver preservation

D. E. Tolhurst; J. Hart

1990-01-01

115

Dissecting Diversity Part II  

ERIC Educational Resources Information Center

|This article presents "Dissecting Diversity, Part II," the conclusion of a wide-ranging two-part roundtable discussion on diversity in higher education. The participants were as follows: Lezli Baskerville, J.D., President and CEO of the National Association for Equal Opportunity (NAFEO); Dr. Gerald E. Gipp, Executive Director of the American…

Matthews, Frank

2005-01-01

116

Video Gallery: Shark Dissection  

NSDL National Science Digital Library

This video gallery is from the Museum's Seminars on Science, a series of distance-learning courses designed to help educators meet the new national science standards. There are 16 videos each covering dissection of a different part of the dogfish shark. There is a downloadable pdf for each video.

117

Doing without Dissection.  

ERIC Educational Resources Information Center

|Both the National Science Teachers Association (NSTA) and the National Association of Biology Teachers (NABT) have issued position statements on the use of animals in the classroom. Dissection has not become extinct, but its role is far smaller than it used to be. (MLF)|

Texley, Juliana

1992-01-01

118

Traumatic cervical artery dissection.  

PubMed

Traumatic cervical artery dissection (TCAD) is a complication of severe blunt head or neck trauma, the main cause being motor vehicle accidents. TCAD are increasingly recognized, and incidences of up to 0.86% for internal carotid and 0.53% for traumatic vertebral artery dissections (TVAD) among blunt trauma victims are reported. Diagnostic evaluation for TCAD is mandatory in the presence of (1) hemorrhage of potential arterial origin originating from the nose, ears, mouth, or a wound; (2) expanding cervical hematoma; (3) cervical bruit in a patient >50 years of age; (4) evidence of acute infarct at brain imaging; (5) unexplained central or lateralizing neurological deficit or transient ischemic attack, or (6) Horner syndrome, neck or head pain. In addition, a number of centers screen asymptomatic patients with blunt trauma for TCAD. Catheter angiography is the standard of reference for diagnosis of TCAD. Color duplex ultrasound, computed tomographic, and magnetic resonance angiography are noninvasive screening alternatives, but each method has its diagnostic limitations compared to catheter angiography. Anticoagulants and antiplatelet drugs may prevent ischemic stroke, but bleeding from traumatized tissues may offset the benefits of antithrombotic treatment. Endovascular therapy of dissected vessels, thrombarterectomy, direct suture of intimal tears, and extracranial-intracranial bypass should be considered in exceptional cases. Neurological outcome is probably worse in TCAD compared to spontaneous CAD, although it is unclear whether this is due to dissection-induced ischemic stroke or associated traumatic lesions. PMID:17290111

Nedeltchev, Krassen; Baumgartner, Ralf W

2005-01-01

119

Spontaneous coronary artery dissection.  

PubMed

Spontaneous coronary artery dissection (SCAD) is an infrequent condition that is underdiagnosed. There is a predilection for young women without traditional cardiovascular risk factors, and it is increasingly diagnosed in women who are not peripartum. We discovered an association between SCAD and fibromuscular dysplasia (FMD), in which most women with nonatherosclerotic SCAD were found to have FMD in another vascular territory. We suspect that these seemingly healthy patients have underlying coronary FMD that predisposed them to coronary dissection. Medical treatment of SCAD includes antiplatelet therapy and ?-blockade. Revascularization of SCAD patients might be challenging, and the recommendation for stenting or surgery depends on their clinical status and the dissected coronary anatomy. The long-term outcome of patients who survived their SCAD event is generally good, however, they are at risk for recurrent dissection and major cardiovascular events, and thus should be closely monitored by cardiovascular specialists. This review summarizes the epidemiology, associated etiology, diagnosis, management, and outcome of patients with SCAD. PMID:23498840

Saw, Jacqueline

2013-03-13

120

Lymphnode dissection in breast cancer  

Microsoft Academic Search

Background: Along with the ongoing modifications in treatment of primary breast cancer, the purpose and extent of lymph-node dissection\\u000a has changed. The following is an overview of the current knowledge and practice of lymph-node dissection in breast cancer,\\u000a with special regard to expected developments in the near future. Axillary dissection is described as a ten-step procedure,\\u000a including dissection of level-I

A. Bembenek; P. M. Schlag

2000-01-01

121

Phosphoproteomic identification and phylogenetic analysis of ribosomal P-proteins in Populus dormant terminal buds  

Microsoft Academic Search

To better understand the role that reversible phosphorylation plays in woody plant ribosomal P-protein function, we initiated\\u000a a phosphoproteomic investigation of P-proteins from Populus dormant terminal buds. Using gel-free (in-solution) protein digestion and phosphopeptide enrichment combined with a nanoUPLC–ESI–MS\\/MS\\u000a strategy, we identified six phosphorylation sites on eight P-proteins from Populus dormant terminal buds. Among these, six Ser sites and one

Chang-Cai Liu; Tian-Cong Lu; Hua-Hua Li; Hong-Xia Wang; Gui-Feng Liu; Ling Ma; Chuan-Ping Yang; Bai-Chen Wang

2010-01-01

122

Identifying Drug Effects via Pathway Alterations using an Integer Linear Programming Optimization Formulation on Phosphoproteomic Data  

Microsoft Academic Search

Understanding the mechanisms of cell function and drug action is a major endeavor in the pharmaceutical industry. Drug effects are governed by the intrinsic properties of the drug (i.e., selectivity and potency) and the specific signaling transduction network of the host (i.e., normal vs. diseased cells). Here, we describe an unbiased, phosphoproteomic-based approach to identify drug effects by monitoring drug-induced

Alexander Mitsos; Ioannis N. Melas; Paraskeuas Siminelakis; Aikaterini D. Chairakaki; Julio Saez-Rodriguez; Leonidas G. Alexopoulos

2009-01-01

123

Phosphoproteomic Analysis of Seed Maturation in Arabidopsis, Rapeseed, and Soybean1[C][W][OA  

PubMed Central

To characterize protein phosphorylation in developing seed, a large-scale, mass spectrometry-based phosphoproteomic study was performed on whole seeds at five sequential stages of development in soybean (Glycine max), rapeseed (Brassica napus), and Arabidopsis (Arabidopsis thaliana). Phosphopeptides were enriched from 0.5 mg of total peptides using a combined strategy of immobilized metal affinity and metal oxide affinity chromatography. Enriched phosphopeptides were analyzed by Orbitrap tandem mass spectrometry and mass spectra mined against cognate genome or cDNA databases in both forward and randomized orientations, the latter to calculate false discovery rate. We identified a total of 2,001 phosphopeptides containing 1,026 unambiguous phosphorylation sites from 956 proteins, with an average false discovery rate of 0.78% for the entire study. The entire data set was uploaded into the Plant Protein Phosphorylation Database (www.p3db.org), including all meta-data and annotated spectra. The Plant Protein Phosphorylation Database is a portal for all plant phosphorylation data and allows for homology-based querying of experimentally determined phosphosites. Comparisons with other large-scale phosphoproteomic studies determined that 652 of the phosphoproteins are novel to this study. The unique proteins fall into several Gene Ontology categories, some of which are overrepresented in our study as well as other large-scale phosphoproteomic studies, including metabolic process and RNA binding; other categories are only overrepresented in our study, like embryonic development. This investigation shows the importance of analyzing multiple plants and plant organs to comprehensively map the complete plant phosphoproteome.

Meyer, Louis J.; Gao, Jianjiong; Xu, Dong; Thelen, Jay J.

2012-01-01

124

StageTip-Based HAMMOC, an Efficient and Inexpensive Phosphopeptide Enrichment Method for Plant Shotgun Phosphoproteomics.  

PubMed

Phosphopeptide enrichment is the most critical step for successful LC-MS/MS-based shotgun phosphoproteomics. Recent technological improvements have made selective phosphopeptide enrichment from non-fractionated whole cell lysate digests with a single-step procedure possible. Here, a handy protocol is described for phosphopeptide enrichment from plant materials using hydroxy acid-modified metal oxide chromatography (HAMMMOC) with a stop-and-go-extraction tip (StageTip). PMID:24136549

Nakagami, Hirofumi

2014-01-01

125

Sensitive kinase assay linked with phosphoproteomics for identifying direct kinase substrates  

PubMed Central

Our understanding of the molecular control of many disease pathologies requires the identification of direct substrates targeted by specific protein kinases. Here we describe an integrated proteomic strategy, termed kinase assay linked with phosphoproteomics, which combines a sensitive kinase reaction with endogenous kinase-dependent phosphoproteomics to identify direct substrates of protein kinases. The unique in vitro kinase reaction is carried out in a highly efficient manner using a pool of peptides derived directly from cellular kinase substrates and then dephosphorylated as substrate candidates. The resulting newly phosphorylated peptides are then isolated and identified by mass spectrometry. A further comparison of these in vitro phosphorylated peptides with phosphopeptides derived from endogenous proteins isolated from cells in which the kinase is either active or inhibited reveals new candidate protein substrates. The kinase assay linked with phosphoproteomics strategy was applied to identify unique substrates of spleen tyrosine kinase (Syk), a protein-tyrosine kinase with duel properties of an oncogene and a tumor suppressor in distinctive cell types. We identified 64 and 23 direct substrates of Syk specific to B cells and breast cancer cells, respectively. Both known and unique substrates, including multiple centrosomal substrates for Syk, were identified, supporting a unique mechanism that Syk negatively affects cell division through its centrosomal kinase activity.

Xue, Liang; Wang, Wen-Horng; Iliuk, Anton; Hu, Lianghai; Galan, Jacob A.; Yu, Shuai; Hans, Michael; Geahlen, Robert L.; Tao, W. Andy

2012-01-01

126

Phosphoproteomics-Based Modeling Defines the Regulatory Mechanism Underlying Aberrant EGFR Signaling  

PubMed Central

Background Mutation of the epidermal growth factor receptor (EGFR) results in a discordant cell signaling, leading to the development of various diseases. However, the mechanism underlying the alteration of downstream signaling due to such mutation has not yet been completely understood at the system level. Here, we report a phosphoproteomics-based methodology for characterizing the regulatory mechanism underlying aberrant EGFR signaling using computational network modeling. Methodology/Principal Findings Our phosphoproteomic analysis of the mutation at tyrosine 992 (Y992), one of the multifunctional docking sites of EGFR, revealed network-wide effects of the mutation on EGF signaling in a time-resolved manner. Computational modeling based on the temporal activation profiles enabled us to not only rediscover already-known protein interactions with Y992 and internalization property of mutated EGFR but also further gain model-driven insights into the effect of cellular content and the regulation of EGFR degradation. Our kinetic model also suggested critical reactions facilitating the reconstruction of the diverse effects of the mutation on phosphoproteome dynamics. Conclusions/Significance Our integrative approach provided a mechanistic description of the disorders of mutated EGFR signaling networks, which could facilitate the development of a systematic strategy toward controlling disease-related cell signaling.

Tasaki, Shinya; Nagasaki, Masao; Kozuka-Hata, Hiroko; Semba, Kentaro; Gotoh, Noriko; Hattori, Seisuke; Inoue, Jun-ichiro; Yamamoto, Tadashi; Miyano, Satoru; Sugano, Sumio; Oyama, Masaaki

2010-01-01

127

Tandem metal-oxide affinity chromatography for enhanced depth of phosphoproteome analysis.  

PubMed

In eukaryotic cells many diverse cellular functions are regulated by reversible protein phosphorylation. In recent years, phosphoproteomics has become a powerful tool to study protein phosphorylation because it allows unbiased localization, and site-specific quantification, of in vivo phosphorylation of hundreds of proteins in a single experiment. A common strategy to identify phosphoproteins and their phosphorylation sites from complex biological samples is the enrichment of phosphopeptides from digested cellular lysates followed by mass spectrometry. However, despite the high sensitivity of modern mass spectrometers the large dynamic range of protein abundance and the transient nature of protein phosphorylation remained major pitfalls in MS-based phosphoproteomics. Tandem metal-oxide affinity chromatography (MOAC) represents a robust and highly selective approach for the identification and site-specific quantification of low abundant phosphoproteins that is based on the successive enrichment of phosphoproteins and -peptides. This strategy combines protein extraction under denaturing conditions, phosphoprotein enrichment using Al(OH)3-based MOAC, tryptic digestion of enriched phosphoproteins followed by TiO2-based MOAC of phosphopeptides. Thus, tandem MOAC effectively targets the phosphate moiety of phosphoproteins and phosphopeptides and, thus, allows probing of the phosphoproteome to unprecedented depth. PMID:24136551

Beckers, Gerold J M; Hoehenwarter, Wolfgang; Röhrig, Horst; Conrath, Uwe; Weckwerth, Wolfram

2014-01-01

128

Neck dissections: radical to conservative  

PubMed Central

Background Neck dissection is an important surgical procedure for the management of metastatic nodal disease in the neck. The gold standard of neck nodal management has been the radical neck dissection. Any modification in the neck dissection is always compared with this standard. Over the last few decades, in order to alleviate the morbidity of radical neck dissection, several modifications and conservative procedures have been advocated. These procedures retain certain lymphatic or non-lymphatic structures and have been shown not to compromise oncological safety. Methods A literature search of the Medline was carried out for all articles on neck dissections. The articles were systematically reviewed to analyze and trace the evolution of neck dissection. These were then categorized to address the nomenclature, management of node positive and node negative neck including those who had received chemoradiation. Results The present article discusses the neck nodal nomenclature, the radical neck dissection, its modifications and migration to more conservative procedures and possible advances in the near future. Conclusion Radical neck dissection is now replaced with modified radical neck dissections in most situations. Attempts are being made to replace modified radical neck dissections with selective neck dissections for early node positivity. Sentinel node biopsy is being studied to address the issue of node negative neck. More conservative surgeries are likely to replace the 'radical' surgeries of bygone era. This process is facilitated by earlier detection of the disease and better understanding of cancer biology.

Harish, K

2005-01-01

129

Shark Dissection Webcast  

NSDL National Science Digital Library

View this Webcast dissection of four shark species conducted last August at the Birch Aquarium and narrated by Dr. Jeffrey Graham of the Scripps Institution of Oceanography. This is a rare opportunity to learn from a marine biologist as he examines the internal organs of these sharks for the audience. The site also has several short text sections offering life history and behavioral information for those users interested in learning more about sharks in general.

2001-01-01

130

Intracranial arterial dissection  

Microsoft Academic Search

We review the angiographic and CT findings, precipitating factors and clinical features in nine patients with ten intracranial\\u000a arterial dissections. The internal carotid artery was involved in five cases, the vertebral artery in four and the posterior\\u000a inferior cerebellar artery in one. Angiography revealed irregular stenosis in four cases, irregular stenosis and a pseudoaneurysm\\u000a in two, irregular stenosis and irregular

O. Pelkonen; T. Tikkakoski; S. Leinonen; J. Pyhtinen; K. Sotaniemi

1998-01-01

131

Sheep Brain Dissection  

NSDL National Science Digital Library

A sheep brain is used to teach about memory and where it takes place because its brain structure and functions are similar to the human brain. Students will be exposed briefly to the fact that electrochemical connections made between brain cells help us remember the thoughts, skills, experiences, and knowledge that make each of us unique. Through dissections, students will learn about the cortex, brain cells, and where the three main subdivisions of memory (working, long-term, and skill memory) take place.

Science NetLinks (The museum of science, art and human perception at the Palace of Fine Arts;)

2004-04-30

132

Triple quad ICPMS (ICPQQQ) as a new tool for absolute quantitative proteomics and phosphoproteomics.  

PubMed

It is clear that sensitive and interference-free quantification of ICP-detectable elements naturally present in proteins will boost the role of ICPMS in proteomics. In this study, a completely new way of polyatomic interference removal in ICPMS for detection of sulfur (present in the majority of proteins as methionine or cysteine) and phosphorus (present in phosphorylated proteins) is presented. It is based on the concept of tandem mass spectrometry (QQQ) typically used in molecular MS. Briefly, the first quadrupole can be operated as 1 amu window band-pass mass filter to select target analyte ions ((31)P, (32)S, and their on-mass polyatomic interferences). In this way, only selected ions enter the cell and react with O(2), reducing the interferences produced by matrix ions as well as background noise. After optimization of the cell conditions, product ions formed for the targets, (47)PO(+) and (48)SO(+), could be detected with enhanced sensitivity and selectivity. The coupling to capillary HPLC allowed analysis of S- and P-containing species with the lowest detection limits ever published (11 and 6.6 fmol, respectively). The potential of the approach for proteomics studies was demonstrated for the highly sensitive simultaneous absolute quantification of different S-containing peptides and phosphopeptides. PMID:22725632

Diez Fernández, Silvia; Sugishama, Naoki; Ruiz Encinar, Jorge; Sanz-Medel, Alfredo

2012-06-29

133

Global Effects of Kinase Inhibitors on Signaling Networks Revealed by Quantitative Phosphoproteomics  

Microsoft Academic Search

Aberrant signaling causes many diseases, and manipu- lating signaling pathways with kinase inhibitors has emerged as a promising area of drug research. Most kinase inhibitors target the conserved ATP-binding pock- et; therefore specificity is a major concern. Proteomics has previously been used to identify the direct targets of kinase inhibitors upon affinity purification from cellular extracts. Here we introduce a

Cuiping Pan; Jesper V. Olsen; Henrik Daub; Matthias Mann

2009-01-01

134

Quantitative phosphoproteome analysis using a dendrimer conjugation chemistry and tandem mass spectrometry  

Microsoft Academic Search

We present a robust and general method for the identification and relative quantification of phosphorylation sites in complex protein mixtures. It is based on a new chemical derivatization strategy using a dendrimer as a soluble polymer support and tandem mass spectrometry (MS\\/MS). In a single step, phosphorylated peptides are covalently conjugated to a dendrimer in a reaction catalyzed by carbodiimide

W Andy Tao; Bernd Wollscheid; Robert O'Brien; Jimmy K Eng; Xiao-jun Li; Bernd Bodenmiller; Julian D Watts; Leroy Hood; Ruedi Aebersold

2005-01-01

135

Carotid and Vertebral Artery Dissection  

Microsoft Academic Search

INTRODUCTIONCarotid and vertebral artery dissections are potentially disabling and yet probably under-diagnosed, and mainly seem to affect young and middle-aged people (Bogousslavsky et al. 1987). Our review focuses on the mechanisms, possible underlying causes, clinical manifestations, diagnostic tools, treatment and prognosis of both carotid and vertebral dissection.EPIDEMIOLOGYCervical artery dissection accounts for up to 20% of strokes in patients under 30

Marcel Arnold; Marie-Germaine Bousser

2005-01-01

136

Analysis of protein phosphorylation using mass spectrometry: deciphering the phosphoproteome  

Microsoft Academic Search

In signal transduction in eukaryotes, protein phosphorylation is a key event. To understand signaling processes, we must first acquire an inventory of phosphoproteins and their phosphorylation sites under different conditions. Because phosphorylation is a dynamic process, elucidation of signaling networks also requires quantitation of these phosphorylation events. In this article, we outline several methods for enrichment of phosphorylated proteins and

Matthias Mann; Shao-En Ong; Mads Grønborg; Hanno Steen; Ole N. Jensen; Akhilesh Pandey

2002-01-01

137

Phosphoproteomic analysis of apoptotic hematopoietic stem cells from hemoglobin E\\/?-thalassemia  

Microsoft Academic Search

Background  Hemoglobin E\\/?-thalassemia is particularly common in Southeast Asia and has variable symptoms ranging from mild to severe\\u000a anemia. Previous investigations demonstrated the remarkable symptoms of ?-thalassemia in terms of the acceleration of apoptotic\\u000a cell death. Ineffective erythropoiesis has been studied in human hematopoietic stem cells, however the distinct apoptotic\\u000a mechanism was unclear.\\u000a \\u000a \\u000a \\u000a \\u000a Methods  The phosphoproteome of bone marrow HSCs\\/CD34+ cells from

Saranyoo Ponnikorn; Tasanee Panichakul; Kitima Sresanga; Chokdee Wongborisuth; Sittiruk Roytrakul; Suradej Hongeng; Sumalee Tungpradabkul

2011-01-01

138

"Dissection" of a Hair Dryer  

ERIC Educational Resources Information Center

|The electrical design of the common hair dryer is based almost entirely on relatively simple principles learned in introductory physics classes. Just as biology students dissect a frog to see the principles of anatomy in action, physics students can "dissect" a hair dryer to see how principles of electricity are used in a real system. They can…

Eisenstein, Stan; Simpson, Jeff

2008-01-01

139

Phosphoproteome analysis of isoflurane-protected heart mitochondria: phosphorylation of adenine nucleotide translocator-1 on Tyr194 regulates mitochondrial function  

Microsoft Academic Search

Aims Reversible phosphorylation of mitochondrial proteins is essential in the regulation of respiratory function, energy metabolism, and mitochondrion-mediated cell death. We hypothesized that mitochon- drial protein phosphorylation plays a critical role in cardioprotection during pre and postconditioning, two of the most efficient anti-ischaemic therapies. Methods and results Using phosphoproteomic approaches, we investigated the profiles of phosphory- lated proteins in Wistar

Jianhua Feng; Min Zhu; Marcus C. Schaub; Peter Gehrig; Bernd Roschitzki; Eliana Lucchinetti; Michael Zaugg

140

Spontaneous arterial dissection  

Microsoft Academic Search

Opinion statement  \\u000a \\u000a \\u000a \\u000a \\u000a – \\u000a \\u000a There is no controlled study for the best treatment or management of cervicocerebral artery dissection (CAD).\\u000a \\u000a \\u000a \\u000a \\u000a – \\u000a \\u000a Rationale initial empiric treatment in acute CAD to prevent secondary embolism is partial thromboplastin time (PTT)-guided\\u000a anticoagulation by intravenous heparin followed by anticoagulation with warfarin.\\u000a \\u000a \\u000a \\u000a \\u000a – \\u000a \\u000a Carotid surgery for treatment of CAD is not recommended anymore with the possible exception

Tobias Brandt; Louis Caplan

2001-01-01

141

Large-scale phosphoproteomics analysis of whole saliva reveals a distinct phosphorylation pattern.  

PubMed

In-depth knowledge of bodily fluid phosphoproteomes, such as whole saliva, is limited. To better understand the whole saliva phosphoproteome, we generated a large-scale catalog of phosphorylated proteins. To circumvent the wide dynamic range of phosphoprotein abundance in whole saliva, we combined dynamic range compression using hexapeptide beads, strong cation exchange HPLC peptide fractionation, and immobilized metal affinity chromatography prior to mass spectrometry. In total, 217 unique phosphopeptides sites were identified representing 85 distinct phosphoproteins at 2.3% global FDR. From these peptides, 129 distinct phosphorylation sites were identified of which 57 were previously known, but only 11 of which had been previously identified in whole saliva. Cellular localization analysis revealed salivary phosphoproteins had a distribution similar to all known salivary proteins, but with less relative representation in "extracellular" and "plasma membrane" categories compared to salivary glycoproteins. Sequence alignment showed that phosphorylation occurred at acidic-directed kinase, proline-directed, and basophilic motifs. This differs from plasma phosphoproteins, which predominantly occur at Golgi casein kinase recognized sequences. Collectively, these results suggest diverse functions for salivary phosphoproteins and multiple kinases involved in their processing and secretion. In all, this study should lay groundwork for future elucidation of the functions of salivary protein phosphorylation. PMID:21299198

Stone, Matthew D; Chen, Xiaobing; McGowan, Thomas; Bandhakavi, Sricharan; Cheng, Bin; Rhodus, Nelson L; Griffin, Timothy J

2011-03-01

142

Large scale phosphoproteome analysis of LNCaP human prostate cancer cells  

PubMed Central

Prostate cancer is the most frequently diagnosed cancer among men in the western world. The androgen receptor, a phosphoprotein, is suspected to be involved in all stages of the prostate cancer. Androgen receptor activity can be modulated by various kinases such as PKA, MAPK, AKT, and Src. Phosphorylation is an important post-translational modification and serves as a molecular on/off switch to regulate signaling. Disruptions of cellular phosphorylation are associated with various diseases such as cancer and kinases provide important drug targets. Here we present an analysis of the phosphoproteome in LNCaP human prostate cancer cells. The analytical strategy employed used proteomics based methodologies with a combination of detergent and chaotropic reagent during trypsin digestion followed by titanium dioxide enrichment of phosphopeptides. Over the course of multiple analyses by mass spectrometry we identified a total of 746 phosphorylation sites in 540 phosphopeptides corresponding to 116 phosphoproteins, of which 56 have not been previously reported. Phosphoproteins identified included transcription factors, co-regulators of the androgen receptor, and cancer-related proteins that include ?-catenin, USP10, and histone deacetylase-2. The information of signaling pathways, motifs of phosphorylated peptides, biological processes, molecular functions, cellular components, and protein interactions from the identified phosphoproteins established a map of phosphoproteome and signaling pathways in LNCaP cells.

Myung, Jae-Kyung; Sadar, Marianne D

2012-01-01

143

Phosphoproteomic analysis of electroacupuncture analgesia in an inflammatory pain rat model.  

PubMed

The phosphorylation changes of nociceptive signaling proteins in the spinal cord dorsal horn (SCDH) are important in creating exaggerated pain following peripheral inflammation. Electroacupuncture (EA) has been widely used to relieve acute and chronic inflammatory pain in human and experimental pain models. In the present study, we performed a phosphoproteomic analysis to investigate whether EA alters protein phosphorylation in SCDH to attenuate pain development. Inflammatory hyperalgesia was induced by intraplantar injection of complete Freund's adjuvant (CFA) into the rat hind paw. EA treatment at ST36 and SP6 acupoints alleviated thermal hyperalgesia of the CFA-induced inflammatory pain model rats. The SCDH proteins from the control, inflammatory pain model and EA treatment rats were separated by 2-dimensional gel electrophoresis and the alterations in phosphoproteins were detected by Pro-Q Diamond staining. Eight proteins were differentially phosphorylated following EA treatment in the inflammatory pain model. Aldolase C, nascent polypeptide-associated complex ?, stress-induced phosphoprotein 1 and heat shock protein 90 were identified as phosphoproteins whose expression was increased, whereas GDP dissociation inhibitor 1, thiamine triphosphatase, phosphoglycerate kinase 1 and 14-3-3 ? were phosphoproteins whose expression was decreased. This is the first phosphoproteomic screening study to elucidate the working mechanisms of EA analgesia. The results suggest that the regulation of cellular pathways in which the identified proteins are involved may be associated with an EA analgesic mechanism. PMID:22576741

Lee, Si-Hyoung; Kim, Sun-Young; Kim, Ji-Hwan; Jung, Hye-Yun; Moon, Jeong-Hee; Bae, Kwang-Hee; Choi, Byung-Tae

2012-04-18

144

Phosphoproteomic profiling reveals vasopressin-regulated phosphorylation sites in collecting duct.  

PubMed

Protein phosphorylation is an important component of vasopressin signaling in the renal collecting duct, but the database of known phosphoproteins is incomplete. We used tandem mass spectrometry to identify vasopressin-regulated phosphorylation events in isolated rat inner medullary collecting duct (IMCD) suspensions. Using multiple search algorithms to identify the phosphopeptides from spectral data, we expanded the size of the existing collecting duct phosphoproteome database from 367 to 1187 entries. Label-free quantification in vasopressin- and vehicle-treated samples detected a significant change in the phosphorylation of 29 of 530 quantified phosphopeptides. The targets include important structural, regulatory, and transporter proteins. The vasopressin-regulated sites included two known sites (Ser-486 and Ser-499) present in the urea channel UT-A1 and one previously unknown site (Ser-84) on vasopressin-sensitive urea channels UT-A1 and UT-A3. In vitro assays using synthetic peptides showed that purified protein kinase A (PKA) could phosphorylate all three sites, and immunoblotting confirmed the PKA dependence of Ser-84 and Ser-486 phosphorylation. These results expand the known list of collecting duct phosphoproteins and highlight the utility of targeted phosphoproteomic approaches. PMID:20075062

Bansal, Amar D; Hoffert, Jason D; Pisitkun, Trairak; Hwang, Shelly; Chou, Chung-Lin; Boja, Emily S; Wang, Guanghui; Knepper, Mark A

2010-01-14

145

Comprehensive phosphoproteome analysis of INS-1 pancreatic ?-cells using various digestion strategies coupled with liquid chromatography-tandem mass spectrometry.  

PubMed

Type 2 diabetes results from aberrant regulation of the phosphorylation cascade in beta-cells. Phosphorylation in pancreatic beta-cells has not been examined extensively, except with regard to subcellular phosphoproteomes using mitochondria. Thus, robust, comprehensive analytical strategies are needed to characterize the many phosphorylated proteins that exist, because of their low abundance, the low stoichiometry of phosphorylation, and the dynamic regulation of phosphoproteins. In this study, we attempted to generate data on a large-scale phosphoproteome from the INS-1 rat pancreatic beta-cell line using linear ion trap MS/MS. To profile the phosphoproteome in-depth, we used comprehensive phosphoproteomic strategies, including detergent-based protein extraction (SDS and SDC), differential sample preparation (in-gel, in-solution digestion, and FASP), TiO2 enrichment, and MS replicate analyses (MS2-only and multiple-stage activation). All spectra were processed and validated by stringent multiple filtering using target and decoy databases. We identified 2467 distinct phosphorylation sites on 1419 phosphoproteins using 4 mg of INS-1 cell lysate in 24 LC-MS/MS runs, of which 683 (27.7%) were considered novel phosphorylation sites that have not been characterized in human, mouse, or rat homologues. Our informatics data constitute a rich bioinformatics resource for investigating the function of reversible phosphorylation in pancreatic beta-cells. In particular, novel phosphorylation sites on proteins that mediate the pathology of type 2 diabetes, such as Pdx-1, Nkx.2, and Srebf1, will be valuable targets in ongoing phosphoproteomics studies. PMID:22276854

Han, Dohyun; Moon, Sungyoon; Kim, Yikwon; Ho, Won-Kyung; Kim, Kyunggon; Kang, Yup; Jun, Heesook; Kim, Youngsoo

2012-03-14

146

How Safe is High-Power Ultrasonic Dissection?  

PubMed Central

Objective To evaluate the safety of ultrasonic dissection. Summary Background Data High-power ultrasonic dissection is in widespread use for both open and laparoscopic operations and is generally perceived to carry a low risk of collateral damage, but there is no published evidence for this. Methods Under controlled experimental conditions, ultrasonic dissections were performed in pigs using Ultracision (Ethicon) or Autosonix (Tyco/USSC) at the three power settings (3, 4, and 5) in random fashion to mobilize the cardia and fundus, bile duct, hepatic artery, portal vein, aorta from the inferior vena cava, renal vessels, colon, and ureters. The dissections (open and laparoscopic) were carried out on pigs at each power setting with each device. Thermal mapping of the tissues during dissection was performed with an infrared thermal camera and associated software. The animals were killed at the end of each experiment and specimens were harvested for quantitative histology. Results Extreme and equivalent temperature gradients were generated by ultrasonic dissection with both systems. Heat production was directly proportional to the power setting and the activation time. The core body temperature of the animals after completion of the laparoscopic dissections rose by an average of 2.3°C. The zone around the jaws that exceeded 60°C with continuous ultrasonic dissection for 10 to 15 seconds at level 5 measured 25.3 and 25.7 mm for Ultracision and Autosonix, respectively. At this power setting and an activation time of 15 seconds, the temperature 1.0 cm away from the tips of the instrument exceeded 140°C. Although there was no discernible macroscopic damage, these thermal changes were accompanied by significant histologic injury that extended to the media of large vessels and caused partial- to full-thickness mural damage of the cardia, ureter, and bile duct. Collateral damage was absent or insignificant after dissections at power level 3 with both systems and an activation time not exceeding 5 seconds. Conclusions High-power ultrasonic dissections at level 5 and to a lesser extent level 4 result in considerable heat production that causes proximity collateral damage to adjacent tissues when the continuous activation time exceeds 10 seconds. Ultrasonic dissections near important structures should be conducted at level 3. At power levels of 4 and 5, the ultrasonic energy bursts to the tissue should not exceed 5 seconds at any one time.

Emam, Tarek A.; Cuschieri, Alfred

2003-01-01

147

Analysis of the Rana catesbeiana tadpole tail fin proteome and phosphoproteome during T3-induced apoptosis: identification of a novel type I keratin  

PubMed Central

Background Thyroid hormones (THs) are vital in the maintenance of homeostasis and in the control of development. One postembryonic developmental process that is principally regulated by THs is amphibian metamorphosis. This process has been intensively studied at the genomic level yet very little information at the proteomic level exists. In addition, there is increasing evidence that changes in the phosphoproteome influence TH action. Results Here we identify components of the proteome and phosphoproteome in the tail fin that changed within 48 h of exposure of premetamorphic Rana catesbeiana tadpoles to 10 nM 3,5,3'-triiodothyronine (T3). To this end, we developed a cell and protein fractionation method combined with two-dimensional gel electrophoresis and phosphoprotein-specific staining. Altered proteins were identified using mass spectrometry (MS). We identified and cloned a novel Rana larval type I keratin, RLK I, which may be a target for caspase-mediated proteolysis upon exposure to T3. In addition, the RLK I transcript is reduced during T3-induced and natural metamorphosis which is consistent with a larval keratin. Furthermore, GILT, a protein involved in the immune system, is changed in phosphorylation state which is linked to its activation. Using a complementary MS technique for the analysis of differentially-expressed proteins, isobaric tags for relative and absolute quantitation (iTRAQ) revealed 15 additional proteins whose levels were altered upon T3 treatment. The success of identifying proteins whose levels changed upon T3 treatment with iTRAQ was enhanced through de novo sequencing of MS data and homology database searching. These proteins are involved in apoptosis, extracellular matrix structure, immune system, metabolism, mechanical function, and oxygen transport. Conclusion We have demonstrated the ability to derive proteomics-based information from a model species for postembryonic development for which no genome information is currently available. The present study identifies proteins whose levels and/or phosphorylation states are altered within 48 h of the induction of tadpole tail regression prior to overt remodeling of the tail. In particular, we have identified a novel keratin that is a target for T3-mediated changes in the tail that can serve as an indicator of early response to this hormone.

Domanski, Dominik; Helbing, Caren C

2007-01-01

148

[Endoscopic submucosal dissection].  

PubMed

Endoscopic submucosal dissection (ESD) was developed in Japan but has now also become permanently established in various centers in Europe. ESD is an endoscopic en bloc mucosal resection technique for the treatment of early cancers with a diameter >1 cm and also superficial precancerous lesions, which could only be removed unsatisfactorily in several fragments or with uncertain lateral safety margins using previous loop excision procedures. Using ESD a lesion is excised after circular marking and generous submucosal injection with a safety margin of approximately 5 mm and subsequently resected at the level of the submucosa with a 1-3 mm short diathermic knife. ESD requires high technical skills in interventional endoscopy and is more time-consuming than snare resection techniques. However, numerous studies have shown a clear superiority for ESD with respect to the R0 resection rate and the local recurrence rate. The present article gives a current review of the use of ESD in the upper and lower gastrointestinal tract and demonstrates perspectives of the procedure. PMID:23455659

Hochberger, J; Köhler, P; Kruse, E; Hûppertz, J; Delvaux, M; Gay, G; Wedi, E

2013-03-01

149

Spontaneous Arterial Dissection.  

PubMed

There is no controlled study for the best treatment or management of cervico-cerebral artery dissection (CAD). Rationale initial empiric treatment in acute CAD to prevent secondary embolism is partial thromboplastin time (PTT)-guided anticoagulation by intravenous heparin followed by anticoagulation with warfarin. Carotid surgery for treatment of CAD is not recommended anymore with the possible exception of persisting severe stenosis of the proximal internal carotid artery (ICA). There could be use of carotid angioplasty by balloon dilatation and stenting in selected cases of severe cerebral hemodynamic impairment by bilateral CAD. Duration of secondary prophylaxis by anticoagulation is best guided by Doppler sonography follow-up, and should be continued until normalization of blood flow or until at least 1 year after the vessel is occluded. There is no evidence that pseudoaneurysms increase the risk for embolic complication, and there is no evidence for surgery or continuation of anticoagulation in patients with pseudoaneurysms. Caution should be recommended for exercises that involve excessive head movements (eg, bungee jumping, trampoline jumping, and chiropractic maneuvers). The patient should be informed that recurrent rate is low in nonfamilial cases. Doppler sonography is a low-cost and high-sensitivity method for patients at risk. PMID:11487460

Brandt, Tobias; Caplan, Louis

2001-09-01

150

Aortic dissection presenting with pancreatitis.  

PubMed

Aortic dissections can be challenging to diagnose in the emergency department (ED) because patients can present with a variety of complaints. We present a case involving a woman with multiple comorbidities, who had experienced intermittent abdominal pain for several months, which worsened in the days leading up to her ED visit. She was diagnosed with pancreatitis based on her history and blood work but, incidentally, on computed tomographic scan, also was found to have a Stanford type B aortic dissection. Her dissection and pancreatitis were managed medically with tight blood pressure control without the need for surgical intervention. Several case studies associating acute aortic dissection with acute pancreatitis have been published, but it remains unclear whether these 2 conditions have a causal relationship. PMID:23602744

Pham, Thuy V; Nable, Jose V

2013-04-17

151

Aortic dissection and cocaine use.  

PubMed

Most of the cocaine - deaths are said to be related to cardiovascular complications. This paper addresses a rather infrequent complication of chronic cocaine use, represented by the aortic dissection. The case in point pertains to a 45-year-old, caucasian male, substance abuser who suffered an aortic dissection following the use of cocaine. Blood concentrations of cocaine and benzoylecgonine were considered not to be within a potentially toxic range. PMID:21907939

Marella, Gian Luca; Furnari, Carmelo; Perfetti, Emilio; Arcudi, Giovanni

2011-07-12

152

Nonsyndromic genetic predisposition to aortic dissection  

Microsoft Academic Search

The major diseases affecting the aorta are aortic aneurysms and dissections, with patients with acute dissections often presenting in the emergency department (ED). Recent studies demonstrate a strong genetic predisposition to thoracic aortic aneurysms and dissections, independent of syndromes traditionally considered to predispose to aortic disease (such as Marfan syndrome). Nonsyndromic familial thoracic aortic aneurysms and dissections are inherited in

Sumera N Hasham; Matthew R Lewin; Van T Tran; Hariyadarshi Pannu; Ann Muilenburg; Marcia Willing; Dianna M Milewicz

2004-01-01

153

The dissections of craniocervical arteries.  

PubMed

Dissection of craniocervical arteries internal carotid artery (ICA), or vertebral artery (VA) is an increasingly recognized entity and infrequent cause of stroke. We investigated 8 patients (4 women and 4 men) with dissections of the craniocervical arteries. Diagnostic procedures for detection of craniocervical dissection included: extracranial ultrasound-color Doppler flow imaging (CDFI) of carotid and vertebral arteries, transcranial Doppler sonography (TCD) and radiological computed tomography (CT) and digital subtractive angiography (DSA) examinations. Ultrasound findings (CDFI of carotid and vertebral arteries) were positive for vessel dissection in seven patients (or 87.5 per cent) and negative in one patient. DSA was consistent with dissection in five patients (or 62.5 per cent), negative in one, while in two patients the examination was not performed due to known allergy to contrast media. Five patients (62.5 per cent) were treated with anticoagulants, one with suppressors of platelet aggregation, and two patients were operated. Six patients (75 per cent) after the treatment showed partial recovery of neurological defects, and an improvement of ultrasound finding of dissected arteries. In one patient, following operation, stroke developed with deterioration of motor deficit, and one patient was readmitted three months later due to a newly developed stroke and soon died. The diagnosis should be suspected in any young or middle-age patient with new onset of otherwise unexplained unremitting headache or neck ache, especially in association with transient or permanent focal neurological deficits. PMID:16417172

Pasi?, Marija Bosnjak; Solter, Vesna Vargek; Seri?, Vesna; Uremovi?, Melita; Vidrih, Branka; Lisak, Marijana; Demarin, Vida

2005-12-01

154

Emergency management of spontaneous coronary artery dissection.  

PubMed

Six cases of spontaneous coronary arteries dissection are reported. In one patient, triple vessel spontaneous coronary artery dissection was identified. Another patient presented spontaneous left main coronary artery dissection. In one case we found the spontaneous dissection of the left anterior descending artery associated with distal aortic arch dissection. These conditions are very rare and may present a surgical dilemma. Causative factors and underlying pathology are clarified. Prompt diagnosis and surgical intervention is safe and effective. Early recognition of left main coronary artery dissection or three-vessel dissection is essential because urgent coronary artery bypass grafting may be life saving. PMID:11887053

Bonacchi, M; Prifti, E; Giunti, G; Frati, G; Leacche, M; Brancaccio, G; Sani, G

2002-04-01

155

Unraveling the phosphoproteome dynamics in mammal mitochondria from a network perspective.  

PubMed

With mitochondrion garnering more attention for its inextricable involvement in pathophysiological conditions, it seems imperative to understand the means by which the molecular pathways harbored in this organelle are regulated. Protein phosphorylation has been considered a central event in cellular signaling and, more recently, in the modulation of mitochondrial activity. Efforts have been made to understand the molecular mechanisms by which protein phosphorylation regulates mitochondrial signaling. With the advances in mass-spectrometry-based proteomics, there is a substantial hope and expectation in the increased knowledge of protein phosphorylation profile and its mode of regulation. On the basis of phosphorylation profiles, attempts have been made to disclose the kinases involved and how they control the molecular processes in mitochondria and, consequently, the cellular outcomes. Still, few studies have focused on mitochondrial phosphoproteome profiling, particularly in diseases. The present study reviews current data on protein phosphorylation profiling in mitochondria, the potential kinases involved and how pathophysiological conditions modulate the mitochondrial phosphoproteome. To integrate data from distinct research papers, we performed network analysis, with bioinformatic tools like Cytoscape, String, and PANTHER taking into consideration variables such as tissue specificity, biological processes, molecular functions, and pathophysiological conditions. For instance, data retrieved from these analyses evidence some homology in the mitochondrial phosphoproteome among liver and heart, with proteins from transport and oxidative phosphorylation clusters particularly susceptible to phosphorylation. A distinct profile was noticed for adipocytes, with proteins form metabolic processes, namely, triglycerides metabolism, as the main targets of phosphorylation. Regarding disease conditions, more phosphorylated proteins were observed in diabetics with some distinct phosphoproteins identified in type 2 prediabetic states and early type 2 diabetes mellitus. Heart-failure-related phosphorylated proteins are in much lower amount and are mainly involved in transport and metabolism. Nevertheless, technical considerations related to mitochondria isolation and protein separation should be considered in data comparison among different proteomic studies. Data from the present review will certainly open new perspectives of protein phosphorylation in mitochondria and will help to envisage future studies targeting the underlying regulatory mechanisms. PMID:23964737

Padrão, Ana Isabel; Vitorino, Rui; Duarte, José Alberto; Ferreira, Rita; Amado, Francisco

2013-09-06

156

Biology teachers' attitudes to dissection and alternatives.  

PubMed

A survey of 5000 American middle and high school level biology teachers was completed to assess attitudes and classroom practice relating to dissection and alternative teaching methods. A preliminary sample of 494 respondents revealed that 79% of teachers used dissection to teach biology. While 72% believed that dissection was an important part of the curriculum, 17% disagreed; 69% considered dissection to be an essential hands-on activity. While 31% believed that alternatives were as good as dissection for teaching anatomy and physiology, 55% disagreed. The primary reason given for continuing dissection, rather than exclusively using alternatives, was the hands-on aspect of dissection (69%). While the majority (66%) of biology teachers favoured student choice between dissection and other learning methods, 20% disagreed. Although the effectiveness of alternative methods has been documented, and ethical arguments against dissection have been advanced, the mainstream introduction of humane alternatives to dissection requires a transformation of the beliefs, experience and practice of biology teachers. PMID:23581121

King, Lesley A; Ross, Cheryl L; Stephens, Martin L; Rowan, Andrew N

2004-06-01

157

Activation of aortic endothelial cells by oxidized phospholipids: a phosphoproteomic analysis  

PubMed Central

Previous studies have shown that oxidized products of the phospholipid PAPC (Ox-PAPC) are strong activators of aortic endothelial cells and play an important role in atherosclerosis and other inflammatory diseases. We and others have demonstrated that Ox-PAPC activates specific signaling pathways and regulates a large number of genes. Using a phosphoproteomic approach based on phosphopeptide enrichment and mass spectrometry analysis, we identified candidate changes in Ox-PAPC-induced protein phosphorylation of 228 proteins. Functional annotation of these proteins showed an enrichment of the regulation of cytoskeleton, junctional components, and tyrosine kinases, all of which may contribute to the phenotypic and molecular changes observed in endothelial cells treated with Ox-PAPC. Many changes in protein phosphorylation induced by Ox-PAPC are reported here for the first time and provide new insights into the mechanism of activation by oxidized lipids, including phosphorylation-based signal transduction.

Zimman, Alejandro; Chen, Sharon S.; Komisopoulou, Evangelia; Titz, Bjoern; Martinez-Pinna, Roxana; Kafi, Aarya; Berliner, Judith A.; Graeber, Thomas G.

2010-01-01

158

Robust phosphoproteome enrichment using monodisperse microsphere-based immobilized titanium (IV) ion affinity chromatography.  

PubMed

Mass spectrometry (MS)-based proteomics has become the preferred tool for the analysis of protein phosphorylation. To be successful at such an endeavor, there is a requirement for an efficient enrichment of phosphopeptides. This is necessary because of the substoichiometric nature of phosphorylation at a given site and the complexity of the cell. Recently, new alternative materials have emerged that allow excellent and robust enrichment of phosphopeptides. These monodisperse microsphere-based immobilized metal ion affinity chromatography (IMAC) resins incorporate a flexible linker terminated with phosphonate groups that chelate either zirconium or titanium ions. The chelated zirconium or titanium ions bind specifically to phosphopeptides, with an affinity that is similar to that of other widely used metal oxide affinity chromatography materials (typically TiO(2)). Here we present a detailed protocol for the preparation of monodisperse microsphere-based Ti(4+)-IMAC adsorbents and the subsequent enrichment process. Furthermore, we discuss general pitfalls and crucial steps in the preparation of phosphoproteomics samples before enrichment and, just as importantly, in the subsequent mass spectrometric analysis. Key points such as lysis, preparation of the chromatographic system for analysis and the most appropriate methods for sequencing phosphopeptides are discussed. Bioinformatics analysis specifically relating to site localization is also addressed. Finally, we demonstrate how the protocols provided are appropriate for both single-protein analysis and the screening of entire phosphoproteomes. It takes ?2 weeks to complete the protocol: 1 week to prepare the Ti(4+)-IMAC material, 2 d for sample preparation, 3 d for MS analysis of the enriched sample and 2 d for data analysis. PMID:23391890

Zhou, Houjiang; Ye, Mingliang; Dong, Jing; Corradini, Eleonora; Cristobal, Alba; Heck, Albert J R; Zou, Hanfa; Mohammed, Shabaz

2013-02-07

159

Large-scale phosphoproteomic analysis of membrane proteins in renal proximal and distal tubule  

PubMed Central

Recent advances in mass spectrometry (MS) have provided means for large-scale phosphoproteomic profiling of specific tissues. Here, we report results from large-scale tandem MS [liquid chromatography (LC)-MS/MS]-based phosphoproteomic profiling of biochemically isolated membranes from the renal cortex, with focus on transporters and regulatory proteins. Data sets were filtered (by target-decoy analysis) to limit false-positive identifications to <2%. A total of 7,125 unique nonphosphorylated and 743 unique phosphorylated peptides were identified. Among the phosphopeptides identified were sites on transporter proteins, i.e., solute carrier (Slc, n = 63), ATP-binding cassette (Abc, n = 4), and aquaporin (Aqp, n = 3) family proteins. Database searches reveal that a majority of the phosphorylation sites identified in transporter proteins were previously unreported. Most of the Slc family proteins are apical or basolateral transporters expressed in proximal tubule cells, including proteins known to mediate transport of glucose, amino acids, organic ions, and inorganic ions. In addition, we identified potentially important phosphorylation sites for transport proteins from distal nephron segments, including the bumetanide-sensitive Na-K-2Cl cotransporter (Slc12a1 or NKCC2) at Ser87, Thr101, and Ser126 and the thiazide-sensitive Na-Cl cotransporter (Slc12a3 or NCC) at Ser71 and Ser124. A subset of phosphorylation sites in regulatory proteins coincided with known functional motifs, suggesting specific regulatory roles. An online database from this study (http://dir.nhlbi.nih.gov/papers/lkem/rcmpd/) provides a resource for future studies of transporter regulation.

Feric, Marina; Zhao, Boyang; Hoffert, Jason D.; Pisitkun, Trairak

2011-01-01

160

Temporal bone dissection simulation--an update.  

PubMed

We report on our continued development of a virtual simulation for temporal bone dissection that provides stereoscopic display, haptic feedback, and aural simulation into a straightforward, comprehensive learning environment. The multimodal interface provides a seamless simulation for non-deterministic drilling and cutting of bone in the surgical context, as well as an intuitive interface for the intelligent tutor for learning regional anatomy. We present novel methodologies for integrating multimodal and multiresolution data sets, including extension to functional and structural segmentation. We will present our initial efforts to validate this environment. Through continued iterations, it is our hope that the system will provide a valuable tool for training future otologic surgeons as well as an environment for the quantitative evaluation of surgical skill. PMID:15458142

Stredney, D; Wiet, Gregory J; Bryan, J; Sessanna, D; Murakami, Jim; Schmalbrock, P; Powell, Kimerly; Welling, B

2002-01-01

161

Dissecting aortic aneurysm in computed tomography.  

PubMed

The dissecting aortic aneurysm (DAA) is an emergency, and because of that it requires urgent diagnosis and treatment. Many methods may by used to diagnose dissection, including aortography, CT, MRI, traditional and transesophageal ultrasonography. The computed tomography is often used in diagnostic of DAA, thus the knowledge of morphological characteristic of dissection is very important. The most important features of dissection in CT are presence of dissection of intima and two lumens, true and false. Nevertheless, the CT pictures of dissection not always appears like this, and sometimes the two lumens are identified only by their different rates of opacification with contrast material. PMID:15314960

Pas?awski, Marek; Z?omaniec, Janusz; Ruci?ska, Eulalia; Horbaczewska, Anna

2003-01-01

162

Diagnostic imaging for aortic dissection.  

PubMed

Diagnostic imaging for aortic dissection has dramatically changed in recent years. Previously, imaging consisted of conventional X-ray radiography, followed by invasive catheter angiography. Now imaging of dissection is performed primarily with multidetector CT, and to a lesser extent, with ultrasound and MRI. Catheter angiography is used primarily as a means of treating complications. Which modality to choose depends on patient factors, physician preference, and differences in availability of state-of-the-art equipment. All three modalities are highly accurate in experienced hands and have revolutionized the detection and evaluation of this condition. PMID:16253826

Kapustin, Andrew J; Litt, Harold I

2005-01-01

163

Bilateral common carotid artery dissection.  

PubMed

A 63-year-old Japanese man with no significant medical or family history was admitted for sudden consciousness disturbance, left hemiparesis and shock. Physical examination showed internal carotid artery asymmetry on palpation and significant differential blood pressure in both upper arms. A thoracic CT scan showed classic aortic dissection from the ascending aorta through the common iliac artery, classic dissection of the left common carotid artery and an intramural haematoma in the right common carotid artery. The patient's consciousness level gradually improved, and he underwent emergency surgery involving aortic rebuilding with a synthetic graft. Subsequently, he had a good clinical course. PMID:22783009

Inokuchi, Ryota; Sato, Hajime; Aoki, Yuta; Yahagi, Naoki

2012-07-10

164

``Dissection'' of a Hair Dryer  

NASA Astrophysics Data System (ADS)

The electrical design of the common hair dryer is based almost entirely on relatively simple principles learned in introductory physics classes. Just as biology students dissect a frog to see the principles of anatomy in action, physics students can ``dissect'' a hair dryer to see how principles of electricity are used in a real system. They can discover how engineers solve problems such as how to vary between low and high heat and fan speed by simply moving the position of a single switch. Principles of alternating versus direct current, series and parallel circuits, electrical safety, voltage dividing, ac rectification, power, and measurement of resistance and continuity all come in to play.

Eisenstein, Stan; Simpson, Jeff

2008-12-01

165

Spontaneous multiarterial dissection immediately after childbirth.  

PubMed

Spontaneous coronary artery dissection and vertebral artery dissection are rare, life-threatening conditions. The pathophysiology of spontaneous coronary artery dissection during the peripartum period is poorly understood. We present a case of spontaneous multivessel dissection in a 32-year-old postpartum woman who presented with neck and chest pain. The patient's coronary and vertebral artery dissections were diagnosed with use of multiple imaging methods, and dissection of the internal mammary artery was discovered during surgery. The patient underwent successful coronary artery bypass grafting and remained asymptomatic 2 years later. To our knowledge, this is the first report of simultaneous coronary, vertebral, and internal mammary artery dissection in a postpartum woman. Early recognition and treatment is crucial, given the high mortality rate associated with spontaneous dissection. PMID:23109768

Brantley, Hutton P; Cabarrus, Brian R; Movahed, Assad

2012-01-01

166

Spontaneous Multiarterial Dissection Immediately after Childbirth  

PubMed Central

Spontaneous coronary artery dissection and vertebral artery dissection are rare, life-threatening conditions. The pathophysiology of spontaneous coronary artery dissection during the peripartum period is poorly understood. We present a case of spontaneous multivessel dissection in a 32-year-old postpartum woman who presented with neck and chest pain. The patient's coronary and vertebral artery dissections were diagnosed with use of multiple imaging methods, and dissection of the internal mammary artery was discovered during surgery. The patient underwent successful coronary artery bypass grafting and remained asymptomatic 2 years later. To our knowledge, this is the first report of simultaneous coronary, vertebral, and internal mammary artery dissection in a postpartum woman. Early recognition and treatment is crucial, given the high mortality rate associated with spontaneous dissection.

Brantley, Hutton P.; Cabarrus, Brian R.; Movahed, Assad

2012-01-01

167

Vertebral Artery Dissection Diagnosed with CT  

Microsoft Academic Search

Summary: Vertebral artery dissection after neck manipulation has been well described. A case of bilateral vertebral artery dissection diagnosed with dynamic CT scanning of the neck is reported. The CT appearances and correlative angiographic and MR findings are presented.

J. R. Soper; G. D. Parker; J. M. Hallinan

168

Keeping Dissection Alive for Medical Students  

NSDL National Science Digital Library

This article describes an experiential course with the goal of immersing medical students in a cadaver dissection course abroad. The course was developed because of a reduction in cadaver opportunities and a desire by medical students to gain dissection skills.

2009-11-01

169

Dissection & Science Fairs. [Information Packet.  

ERIC Educational Resources Information Center

|This collection of pamphlets and articles reprinted from other National Anti-Vivisection Society (NAVS) publications was compiled to address the issues of classroom laboratory dissection and the use of animals in science fair projects. Three of the pamphlets contained in this packet are student handbooks designed to help students of elementary,…

National Anti-Vivisection Society, Chicago, IL.

170

Animal Rights Activism Threatens Dissection.  

ERIC Educational Resources Information Center

|Discussed is the movement against the use of dissections in science laboratories. Examples of protests across the United States are included. Compared is the plight of using animals in a biology classroom and the demise of the teaching of evolution in some areas. (KR)|

Holden, Constance

1990-01-01

171

Traumatic bilateral vertebral artery dissection.  

PubMed

Traumatic vertebral artery dissection is not often seen by forensic pathologists, and cases investigated are scarce in the forensic literature. We present the case of a 40-year-old woman cyclist who was struck by a car while wearing a helmet, and was neurologically near normal immediately thereafter at Emergency. She presented 48 h later with acute right hemiparesis, decreasing level of consciousness, and unsteadiness. CT revealed massive cerebellar infarction. CT angiography was normal. The patient died in coma 7 days after injury and autopsy revealed bilateral edematous cerebellar infarction and bilateral vertebral artery dissection. Rotational neck injury and mural tear in the wall of the Atlantic parts of both vertebral arteries is suggested as the possible mechanism of the arterial injury. Head and neck injuries are reported as a precipitating cause of vertebral artery injury. The possible influence of trauma may be further underestimated if longer intervals between vessel dissection and ischemia occur. The current case illustrates that "talk-and-die" syndrome may be due to occult vertebral artery dissection, possibly bilateral. In forensic cases of delayed death after mild trauma to the head and neck, the vertebral arteries should be examined for the cause of death. PMID:21798679

Galtés, Ignasi; Borondo, Juan Carlos; Cos, Mònica; Subirana, Mercè; Martin-Fumadó, Carles; Martín, Carles; Castellà, Josep; Medallo, Jordi

2011-07-27

172

Traumatic bilateral vertebral artery dissection  

Microsoft Academic Search

Traumatic vertebral artery dissection is not often seen by forensic pathologists, and cases investigated are scarce in the forensic literature. We present the case of a 40-year-old woman cyclist who was struck by a car while wearing a helmet, and was neurologically near normal immediately thereafter at Emergency. She presented 48h later with acute right hemiparesis, decreasing level of consciousness,

Ignasi Galtés; Juan Carlos Borondo; Mònica Cos; Mercè Subirana; Carles Martín; Josep Castellà; Jordi Medallo

173

Epidemiology of thoracic aortic dissection  

Microsoft Academic Search

Thoracic aortic dissection (TAD) is estimated to occur at a rate of 3–4 cases per 100,000 persons per year and is associated with a high mortality. Reported rates are probably underestimates of the true incidence of TAD because of difficulties in diagnosis. The incidence of TAD appears to have been increasing over time. TAD is most common in men and

Ludivine Russell; Scott A. LeMaire

2010-01-01

174

Genetic dissection of rice grain shape using a recombinant inbred line population derived from two contrasting parents and fine mapping a pleiotropic quantitative trait locus qGL7  

PubMed Central

Background The three-dimensional shape of grain, measured as grain length, width, and thickness (GL, GW, and GT), is one of the most important components of grain appearance in rice. Determining the genetic basis of variations in grain shape could facilitate efficient improvements in grain appearance. In this study, an F7:8 recombinant inbred line population (RIL) derived from a cross between indica and japonica cultivars (Nanyangzhan and Chuan7) contrasting in grain size was used for quantitative trait locus (QTL) mapping. A genetic linkage map was constructed with 164 simple sequence repeat (SSR) markers. The major aim of this study was to detect a QTL for grain shape and to fine map a minor QTL, qGL7. Results Four QTLs for GL were detected on chromosomes 3 and 7, and 10 QTLs for GW and 9 QTLs for GT were identified on chromosomes 2, 3, 5, 7, 9 and 10, respectively. A total of 28 QTLs were identified, of which several are reported for the first time; four major QTLs and six minor QTLs for grain shape were also commonly detected in both years. The minor QTL, qGL7, exhibited pleiotropic effects on GL, GW, GT, 1000-grain weight (TGW), and spikelets per panicle (SPP) and was further validated in a near isogenic F2 population (NIL-F2). Finally, qGL7 was narrowed down to an interval between InDel marker RID711 and SSR marker RM6389, covering a 258-kb region in the Nipponbare genome, and cosegregated with InDel markers RID710 and RID76. Conclusion Materials with very different phenotypes were used to develop mapping populations to detect QTLs because of their complex genetic background. Progeny tests proved that the minor QTL, qGL7, could display a single mendelian characteristic. Therefore, we suggested that minor QTLs for traits with high heritability could be isolated using a map-based cloning strategy in a large NIL-F2 population. In addition, combinations of different QTLs produced diverse grain shapes, which provide the ability to breed more varieties of rice to satisfy consumer preferences.

2010-01-01

175

Current management of type B aortic dissection  

PubMed Central

Acute aortic dissection is a life-threatening condition associated with high morbidity and mortality. In this article, the authors review basic biology of the aorta and aortic dissection, epidemiology, clinical presentation, diagnostic approach, emergency stabilization measures, and the latest surgical approach for type B dissection.

Tran, T Paul; Khoynezhad, Ali

2009-01-01

176

Elucidating the CXCL12/CXCR4 Signaling Network in Chronic Lymphocytic Leukemia through Phosphoproteomics Analysis  

PubMed Central

Background Chronic Lymphocytic Leukemia (CLL) pathogenesis has been linked to the prolonged survival and/or apoptotic resistance of leukemic B cells in vivo, and is thought to be due to enhanced survival signaling responses to environmental factors that protect CLL cells from spontaneous and chemotherapy-induced death. Although normally associated with cell migration, the chemokine, CXCL12, is one of the factors known to support the survival of CLL cells. Thus, the signaling pathways activated by CXCL12 and its receptor, CXCR4, were investigated as components of these pathways and may represent targets that if inhibited, could render resistant CLL cells more susceptible to chemotherapy. Methodology/Principal Findings To determine the downstream signaling targets that contribute to the survival effects of CXCL12 in CLL, we took a phosphoproteomics approach to identify and compare phosphopeptides in unstimulated and CXCL12-stimulated primary CLL cells. While some of the survival pathways activated by CXCL12 in CLL are known, including Akt and ERK1/2, this approach enabled the identification of additional signaling targets and novel phosphoproteins that could have implications in CLL disease and therapy. In addition to the phosphoproteomics results, we provide evidence from western blot validation that the tumor suppressor, programmed cell death factor 4 (PDCD4), is a previously unidentified phosphorylation target of CXCL12 signaling in all CLL cells probed. Additionally, heat shock protein 27 (HSP27), which mediates anti-apoptotic signaling and has previously been linked to chemotherapeutic resistance, was detected in a subset (?25%) of CLL patients cells examined. Conclusions/Significance Since PDCD4 and HSP27 have previously been associated with cancer and regulation of cell growth and apoptosis, these proteins may have novel implications in CLL cell survival and represent potential therapeutic targets. PDCD4 also represents a previously unknown signaling target of chemokine receptors; therefore, these observations increase our understanding of alternative pathways to migration that may be activated or inhibited by chemokines in the context of cancer cell survival.

O'Hayre, Morgan; Salanga, Catherina L.; Kipps, Thomas J.; Messmer, Davorka; Dorrestein, Pieter C.; Handel, Tracy M.

2010-01-01

177

Spontaneous Dissection of the Superior Mesenteric Artery  

SciTech Connect

Spontaneous dissection of the superior mesenteric artery (SMA) is a rare occurrence, especially when not associated with aortic dissection [1]. Currently, only 28 cases appear to have been reported. Due to the scarcity of cases in the literature, the natural history of isolated, spontaneous SMA dissection is unclear. CT has been reported to be useful for the initial diagnosis of SMA dissection [2-5]. We present two recent cases of spontaneous SMA dissection in which enhanced spiral CT was instrumental in following the disease process and guiding clinical decision making.

Sheldon, Patrick J. [Department of Radiology, University of California San Diego Medical Center, 200 West Arbor Drive, San Diego, CA 92103 (United States); Esther, James B. [Department of Radiology, Beth Israel Deaconess Medical Center, Harvard Medical School, West Campus, CC308E, One Deaconess Road, Boston, MA 02215 (United States); Sheldon, Elana L. [Department of Medicine, University of California San Diego Medical Center, 200 West Arbor Drive, San Diego, CA 92103 (United States); Sparks, Steven R. [Department of Surgery, University of California San Diego Medical Center, 200 West Arbor Drive, San Diego, CA 92103 (United States); Brophy, David P. [Department of Radiology, Beth Israel Deaconess Medical Center, Harvard Medical School, West Campus, CC308E, One Deaconess Road, Boston, MA 02215 (United States); Oglevie, Steven B. [Department of Radiology, University of California San Diego Medical Center, 200 West Arbor Drive, San Diego, CA 92103 (United States)

2001-09-15

178

Phosphoproteomics of collagen receptor networks reveals SHP-2 phosphorylation downstream of wild-type DDR2 and its lung cancer mutants.  

PubMed

Collagen is an important extracellular matrix component that directs many fundamental cellular processes including differentiation, proliferation and motility. The signalling networks driving these processes are propagated by collagen receptors such as the ?1 integrins and the DDRs (discoidin domain receptors). To gain an insight into the molecular mechanisms of collagen receptor signalling, we have performed a quantitative analysis of the phosphorylation networks downstream of collagen activation of integrins and DDR2. Temporal analysis over seven time points identified 424 phosphorylated proteins. Distinct DDR2 tyrosine phosphorylation sites displayed unique temporal activation profiles in agreement with in vitro kinase data. Multiple clustering analysis of the phosphoproteomic data revealed several DDR2 candidate downstream signalling nodes, including SHP-2 (Src homology 2 domain-containing protein tyrosine phosphatase 2), NCK1 (non-catalytic region of tyrosine kinase adaptor protein 1), LYN, SHIP-2 [SH2 (Src homology 2)-domain-containing inositol phosphatase 2], PIK3C2A (phosphatidylinositol-4-phosphate 3-kinase, catalytic subunit type 2?) and PLCL2 (phospholipase C-like 2). Biochemical validation showed that SHP-2 tyrosine phosphorylation is dependent on DDR2 kinase activity. Targeted proteomic profiling of a panel of lung SCC (squamous cell carcinoma) DDR2 mutants demonstrated that SHP-2 is tyrosine-phosphorylated by the L63V and G505S mutants. In contrast, the I638F kinase domain mutant exhibited diminished DDR2 and SHP-2 tyrosine phosphorylation levels which have an inverse relationship with clonogenic potential. Taken together, the results of the present study indicate that SHP-2 is a key signalling node downstream of the DDR2 receptor which may have therapeutic implications in a subset of DDR2 mutations recently uncovered in genome-wide lung SCC sequencing screens. PMID:23822953

Iwai, Leo K; Payne, Leo S; Luczynski, Maciej T; Chang, Francis; Xu, Huifang; Clinton, Ryan W; Paul, Angela; Esposito, Edward A; Gridley, Scott; Leitinger, Birgit; Naegle, Kristen M; Huang, Paul H

2013-09-15

179

Thoracic Aortic Dissection: Are Matrix Metalloproteinases Involved?  

PubMed Central

Thoracic aortic dissection, one of the major diseases affecting the aorta, carries a very high mortality rate. Improving our understanding of the pathobiology of this disease may help us develop medical treatments to prevent dissection and subsequent aneurysm formation and rupture. Dissection is associated with degeneration of the aortic media. Recent studies have shown increased expression and activation of a family of proteolytic enzymes—called matrix metalloproteinases (MMPs)—in dissected aortic tissue, suggesting that MMPs may play a major role in this disease. Inhibition of MMPs may be beneficial in reducing MMP-mediated aortic damage associated with dissection. This article reviews the recent literature and summarizes our current understanding of the role of MMPs in the pathobiology of thoracic aortic dissection. The potential importance of MMP inhibition as a future treatment of aortic dissection is also discussed.

Zhang, Xiaoming; Shen, Ying H.; LeMaire, Scott A.

2010-01-01

180

Netfrog: The Interactive Frog Dissection  

NSDL National Science Digital Library

This tutorial on frog dissection contains an introduction and sections on preparation, skin incisions, muscle incisions, and internal organs. The purpose of this lab activity is to help students learn the anatomy of a frog and provide them with a better understanding of the anatomy of vertebrate animals in general, including humans. This site provides still and motion visuals of preserved and pithed (severed spinal cord) frogs to demonstrate incisions, in addition to text.

Kinzie, Mable

181

Systems-Level Overview of Host Protein Phosphorylation During Shigella flexneri Infection Revealed by Phosphoproteomics.  

PubMed

The enteroinvasive bacterium Shigella flexneri invades the intestinal epithelium of humans. During infection, several injected effector proteins promote bacterial internalization, and interfere with multiple host cell responses. To obtain a systems-level overview of host signaling during infection, we analyzed the global dynamics of protein phosphorylation by liquid chromatography-tandem MS and identified several hundred of proteins undergoing a phosphorylation change during the first hours of infection. Functional bioinformatic analysis revealed that they were mostly related to the cytoskeleton, transcription, signal transduction, and cell cycle. Fuzzy c-means clustering identified six temporal profiles of phosphorylation and a functional module composed of ATM-phosphorylated proteins related to genotoxic stress. Pathway enrichment analysis defined mTOR as the most overrepresented pathway. We showed that mTOR complex 1 and 2 were required for S6 kinase and AKT activation, respectively. Comparison with a published phosphoproteome of Salmonella typhimurium-infected cells revealed a large subset of coregulated phosphoproteins. Finally, we showed that S. flexneri effector OspF affected the phosphorylation of several hundred proteins, thereby demonstrating the wide-reaching impact of a single bacterial effector on the host signaling network. PMID:23828894

Schmutz, Christoph; Ahrné, Erik; Kasper, Christoph A; Tschon, Therese; Sorg, Isabel; Dreier, Roland F; Schmidt, Alexander; Arrieumerlou, Cécile

2013-07-04

182

Tyrosine phosphoproteomics of fibroblast growth factor signaling: a role for insulin receptor substrate-4.  

PubMed

Signal transduction by receptor tyrosine kinases is initiated by recruitment of a variety of signaling proteins to tyrosine-phosphorylated motifs in the activated receptors. Several signaling pathways are thus activated in parallel, the combination of which decides the cellular response. Here, we present a dual strategy for extensive mapping of tyrosine-phosphorylated proteins and probing of signal-dependent protein interactions of a signaling cascade. The approach relies on labeling of cells with "heavy" and "light" isotopic forms of Arg to distinguish two cell populations. First, tyrosine-phosphorylated proteins from stimulated ("heavy"-labeled) and control samples ("normal"-labeled) are isolated and subjected to high sensitivity Fourier transform ion cyclotron resonance mass spectrometry analysis. Next, phosphopeptides corresponding to tyrosine phosphorylation sites identified during the tyrosine phosphoproteomic analysis are used as baits to isolate phosphospecific protein binding partners, which are subsequently identified by mass spectrometry. We used this approach to identify 28 components of the signaling cascade induced by stimulation with the basic fibroblast growth factor. Insulin receptor substrate-4 was identified as a novel candidate in fibroblast growth factor receptor signaling, and we defined phosphorylation-dependent interactions with other components, such as adaptor protein Grb2, of the signaling cascade. Finally, we present evidence for a complex containing insulin receptor substrate-4 and ShcA in signaling by the fibroblast growth factor receptor. PMID:15316024

Hinsby, Anders M; Olsen, Jesper V; Mann, Matthias

2004-08-16

183

Phosphoproteomic Dynamics of Chickpea (Cicer arietinum L.) Reveals Shared and Distinct Components of Dehydration Response.  

PubMed

Reversible protein phosphorylation is a ubiquitous regulatory mechanism that plays critical roles in transducing stress signals to bring about coordinated intracellular responses. To gain better understanding of dehydration response in plants, we have developed a differential phosphoproteome in a food legume, chickpea (Cicer arietinum L.). Three-week-old chickpea seedlings were subjected to progressive dehydration by withdrawing water, and the changes in the phosphorylation status of a large repertoire of proteins were monitored. The proteins were resolved by 2-DE and stained with phosphospecific fluorescent Pro-Q Diamond dye. Mass spectrometric analysis led to the identification of 91 putative phosphoproteins, presumably involved in a variety of functions including cell defense and rescue, photosynthesis and photorespiration, molecular chaperones, and ion transport, among others. Multiple sites of phosphorylation were predicted on several key elements, which include both the regulatory as well as the functional proteins. A critical survey of the phosphorylome revealed a DREPP (developmentally regulated plasma membrane protein) plasma membrane polypeptide family protein, henceforth designated CaDREPP1. The transcripts of CaDREPP1 were found to be differentially regulated under dehydration stress, further corroborating the proteomic results. This work provides new insights into the possible phosphorylation events triggered by the conditions of progressive water-deficit in plants. PMID:24083463

Subba, Pratigya; Barua, Pragya; Kumar, Rajiv; Datta, Asis; Soni, Kamlesh Kumar; Chakraborty, Subhra; Chakraborty, Niranjan

2013-10-08

184

Use of (32)P to study dynamics of the mitochondrial phosphoproteome.  

PubMed

Protein phosphorylation is a well-characterized regulatory mechanism in the cytosol, but remains poorly defined in the mitochondrion. In this study, we characterized the use of (32)P-labeling to monitor the turnover of protein phosphorylation in the heart and liver mitochondria matrix. The (32)P labeling technique was compared and contrasted to Phos-tag protein phosphorylation fluorescent stain and 2D isoelectric focusing. Of the 64 proteins identified by MS spectroscopy in the Phos-Tag gels, over 20 proteins were correlated with (32)P labeling. The high sensitivity of (32)P incorporation detected proteins well below the mass spectrometry and even 2D gel protein detection limits. Phosphate-chase experiments revealed both turnover and phosphate associated protein pool size alterations dependent on initial incubation conditions. Extensive weak phosphate/phosphate metabolite interactions were observed using nondisruptive native gels, providing a novel approach to screen for potential allosteric interactions of phosphate metabolites with matrix proteins. We confirmed the phosphate associations in Complexes V and I due to their critical role in oxidative phosphorylation and to validate the 2D methods. These complexes were isolated by immunocapture, after (32)P labeling in the intact mitochondria, and revealed (32)P-incorporation for the alpha, beta, gamma, OSCP, and d subunits in Complex V and the 75, 51, 42, 23, and 13a kDa subunits in Complex I. These results demonstrate that a dynamic and extensive mitochondrial matrix phosphoproteome exists in heart and liver. PMID:19351177

Aponte, Angel M; Phillips, Darci; Hopper, Rachel K; Johnson, D Thor; Harris, Robert A; Blinova, Ksenia; Boja, Emily S; French, Stephanie; Balaban, Robert S

2009-06-01

185

The phosphoproteome of Arabidopsis plants lacking the oxidative signal-inducible1 (OXI1) protein kinase.  

PubMed

• The AGC protein kinase OXI1 is a key protein in plant responses to oxidative signals, and is important for two oxidative burst-mediated processes: basal resistance to microbial pathogens and root hair growth. To identify possible components of the OXI1 signalling pathway, phosphoproteomic techniques were used to detect alterations in the abundance of phosphorylated proteins and peptides in an oxi1 null mutant of Arabidopsis thaliana. • The relative abundance of phosphorylated proteins was assessed either using two-dimensional gel electrophoresis and staining with the phosphoprotein stain Pro-Q Diamond or by the identification and quantification, by mass spectrometry, of stable-isotope labelled phosphopeptides. • A number of proteins show altered phosphorylation in the oxi1 mutant. Five proteins, including a putative F-box and 3-phosphoinositide-dependent kinase 1, show reduced phosphorylation in the oxi1 mutant, and may be direct or indirect targets of OXI1. Four proteins, including ethylene insensitive 2 and phospholipase d-gamma, show increased phosphorylation in the oxi1 mutant. • This study has identified a range of candidate proteins from the OXI1 signalling pathway. The diverse activities of these proteins, including protein degradation and hormone signalling, may suggest crosstalk between OXI1 and other signal transduction cascades. PMID:21175636

Howden, Andrew J M; Salek, Mogjiborahman; Miguet, Laurent; Pullen, Margaret; Thomas, Benjamin; Knight, Marc R; Sweetlove, Lee J

2010-12-22

186

Visualization and Biochemical Analyses of the Emerging Mammalian 14-3-3-Phosphoproteome*  

PubMed Central

Hundreds of candidate 14-3-3-binding (phospho)proteins have been reported in publications that describe one interaction at a time, as well as high-throughput 14-3-3-affinity and mass spectrometry-based studies. Here, we transcribed these data into a common format, deposited the collated data from low-throughput studies in MINT (http://mint.bio.uniroma2.it/mint), and compared the low- and high-throughput data in VisANT graphs that are easy to analyze and extend. Exploring the graphs prompted questions about technical and biological specificity, which were addressed experimentally, resulting in identification of phosphorylated 14-3-3-binding sites in the mitochondrial import sequence of the iron-sulfur cluster assembly enzyme (ISCU), cytoplasmic domains of the mitochondrial fission factor (MFF), and endoplasmic reticulum-tethered receptor expression-enhancing protein 4 (REEP4), RNA regulator SMAUG2, and cytoskeletal regulatory proteins, namely debrin-like protein (DBNL) and kinesin light chain (KLC) isoforms. Therefore, 14-3-3s undergo physiological interactions with proteins that are destined for diverse subcellular locations. Graphing and validating interactions underpins efforts to use 14-3-3-phosphoproteomics to identify mechanisms and biomarkers for signaling pathways in health and disease.

Johnson, Catherine; Tinti, Michele; Wood, Nicola T.; Campbell, David G.; Toth, Rachel; Dubois, Fanny; Geraghty, Kathryn M.; Wong, Barry H. C.; Brown, Laura J.; Tyler, Jennifer; Gernez, Aurelie; Chen, Shuai; Synowsky, Silvia; MacKintosh, Carol

2011-01-01

187

Ti(4+)-phosphate functionalized cellulose for phosphopeptides enrichment and its application in rice phosphoproteome analysis.  

PubMed

In this study, a novel immobilized metal ion affinity chromatography (IMAC) material for phosphopeptide enrichment was prepared based on modified cellulose and was applied in rice phosphoproteome analysis. Firstly, cellulose was modified with phosphoric acid via esterification, and then Ti(4+) was chelated onto the phosphorylated cellulose. The synthesized materials were ultrafine powders and had good dispersibility in acidic buffer, and as supporting matrix, phosphorylated cellulose exhibited good biocompatibility and chemical stability. Enrichment conditions were optimized and the optimum loading buffer was 40% acetonitrile (ACN) with 6% trifluoroacetic acid (TFA). Finally, the Ti(4+)-phosphate functionalized cellulose was submitted to phosphopeptides enrichment prior to mass spectrometry (MS). For ?-casein lysates, 14 phosphopeptides were detected with high intensities even though the sample concentration was as low as 2 pmol. Besides, 15 phosphopeptides were still identified by using the digest mixture of ?-casein and bovine serum albumin with molar ratio of 1:100, which demonstrated high specificity and sensitivity for phosphopeptides enrichment. 19 phosphoproteins were identified from 200 ?g of salt-free rice leaf protein lysates, while 30 phosphoproteins were identified from salt-stressed rice leaf protein lysates, and most of these proteins were related to the biological processes in response to abiotic stimulus. PMID:22795554

Shen, Feng; Hu, Yufeng; Guan, Ping; Ren, Xueqin

2012-07-01

188

A solid phase extraction-based platform for rapid phosphoproteomic analysis  

PubMed Central

Protein phosphorylation is among the most common and intensely studied post-translational protein modification. It plays crucial roles in virtually all cellular processes and has been implicated in numerous human diseases, including cancer. Traditional biochemical and genetic methods for identifying and monitoring sites of phosphorylation are laborious and slow and in recent years have largely been replaced by mass spectrometric analysis. Improved methods for phosphopeptide enrichment coupled with faster and more sensitive mass spectrometers have led to an explosion in the size of phosphoproteomic datasets. However, wider application of these methods is limited by equipment costs and the resultant high demand for instrument time as well as by a technology gap between biologists and mass spectrometrists. Here we describe a modified two-step enrichment strategy that employs lysC digestion and step elution from self-packed strong cation exchange (SCX) solid phase extraction (SPE) columns followed by immobilized metal ion affinity chromatography (IMAC) and LC-MS/MS analysis using a hybrid LTQ Orbitrap Velos mass spectrometer. The SCX procedure does not require an HPLC system, demands little expertise, and because multiple samples can be processed in parallel, can provide a large savings of time and labor. We demonstrate this method in conjunction with stable isotope labeling to quantify peptides harboring >8,000 unique phosphorylation sites in yeast in 12 hours of instrument analysis time and examine the impact of enzyme choice and instrument platform.

Dephoure, Noah; Gygi, Steven P.

2011-01-01

189

Proteomic and phosphoproteomic profiling during diapause entrance in the flesh fly, Sarcophaga crassipalpis.  

PubMed

Diapause is an alternate developmental pathway that is regulated by the neuroendocrine system in insects. To date, much of the information that has been published regarding the possible molecular events associated with diapause have been at the level of transcription. However, since transcription and translation are not linked in eukaryotic systems, a proteomics approach may represent a better tool to identify the gene products that regulate this period of developmental arrest. In this study, we performed gel-based proteomic and phospho-proteomic analyses to identify proteins that are differentially expressed or differentially phosphorylated in the brain during the initiation of pupal diapause in the flesh fly, Sarcophaga crassipalpis. A total of 27 proteins and phosphoproteins were identified by LC-MS/MS, including 16 that were either upregulated or phosphorylated during diapause, including proteins that function in cellular defense, cell cycle inhibition and neuronal protection. Of equal importance, 11 proteins were identified that were either downregulated at the total protein level, or from nuclear fractions. These included proteins involved in cell proliferation, adult development and aging. These data provide potentially valuable insight into the regulation of insect dormancy as well as the general phenomenon of aging in eukaryotic systems. PMID:21501620

Pavlides, Savvas C; Pavlides, Sheri A; Tammariello, Steven P

2011-04-09

190

Visualization and biochemical analyses of the emerging mammalian 14-3-3-phosphoproteome.  

PubMed

Hundreds of candidate 14-3-3-binding (phospho)proteins have been reported in publications that describe one interaction at a time, as well as high-throughput 14-3-3-affinity and mass spectrometry-based studies. Here, we transcribed these data into a common format, deposited the collated data from low-throughput studies in MINT (http://mint.bio.uniroma2.it/mint), and compared the low- and high-throughput data in VisANT graphs that are easy to analyze and extend. Exploring the graphs prompted questions about technical and biological specificity, which were addressed experimentally, resulting in identification of phosphorylated 14-3-3-binding sites in the mitochondrial import sequence of the iron-sulfur cluster assembly enzyme (ISCU), cytoplasmic domains of the mitochondrial fission factor (MFF), and endoplasmic reticulum-tethered receptor expression-enhancing protein 4 (REEP4), RNA regulator SMAUG2, and cytoskeletal regulatory proteins, namely debrin-like protein (DBNL) and kinesin light chain (KLC) isoforms. Therefore, 14-3-3s undergo physiological interactions with proteins that are destined for diverse subcellular locations. Graphing and validating interactions underpins efforts to use 14-3-3-phosphoproteomics to identify mechanisms and biomarkers for signaling pathways in health and disease. PMID:21725060

Johnson, Catherine; Tinti, Michele; Wood, Nicola T; Campbell, David G; Toth, Rachel; Dubois, Fanny; Geraghty, Kathryn M; Wong, Barry H C; Brown, Laura J; Tyler, Jennifer; Gernez, Aurélie; Chen, Shuai; Synowsky, Silvia; MacKintosh, Carol

2011-07-01

191

Phosphoproteomic mass spectrometry profiling links Src family kinases to escape from HER2 tyrosine kinase inhibition  

PubMed Central

Despite the initial effectiveness of the tyrosine kinase inhibitor lapatinib against HER2 gene-amplified breast cancers, most patients eventually relapse after treatment, implying that tumors acquire mechanisms of drug resistance. To discover these mechanisms, we generated six lapatinib-resistant HER2-overexpressing human breast cancer cell lines. In cells that grew in the presence of lapatinib, HER2 autophosphorylation was undetectable whereas active PI3K-Akt and MAPK were maintained. To identify networks maintaining these signaling pathways, we profiled the tyrosine phosphoproteome of sensitive and resistant cells using an immunoaffinity-enriched mass spectrometry method. We found increased phosphorylation of Src family kinases (SFK) and putative Src substrates in several resistant cell lines. Treatment of these resistant cells with Src kinase inhibitors partially blocked PI3K-Akt signaling and restored lapatinib sensitivity. Further, SFK mRNA expression was upregulated in primary HER2+ tumors treated with lapatinib. Finally, the combination of lapatinib and the Src inhibitor AZD0530 was more effective than lapatinib alone at inhibiting pAkt and growth of established HER2-positive BT-474 xenografts in athymic mice. These data suggest that increased Src kinase activity is a mechanism of lapatinib resistance and support the combination of HER2 antagonists with Src inhibitors early in the treatment of HER2+ breast cancers in order to prevent or overcome resistance to HER2 inhibitors.

Rexer, Brent N.; Ham, Amy-Joan L.; Rinehart, Cammie; Hill, Salisha; Granja-Ingram, Nara de Matos; Gonzalez, Ana Maria; Mills, Gordon B.; Dave, Bhuvanesh; Chang, Jenny C.; Liebler, Daniel C.; Arteaga, Carlos L.

2011-01-01

192

Dissection of Saccharomyces cerevisiae asci.  

PubMed

Yeast is a highly tractable model system that is used to study many different cellular processes. The common laboratory strain Saccharomyces cerevisiae exists in either a haploid or diploid state. The ability to combine alleles from two haploids and the ability to introduce modifications to the genome requires the production and dissection of asci. Asci production from haploid cells begins with the mating of two yeast haploid strains with compatible mating types to produce a diploid strain. This can be accomplished in a number of ways either on solid medium or in liquid. It is advantageous to select for the diploids in medium that selectively promotes their growth compared to either of the haploid strains. The diploids are then allowed to sporulate on nutrient-poor medium to form asci, a bundle of four haploid daughter cells resulting from meiotic reproduction of the diploid. A mixture of vegetative cells and asci is then treated with the enzyme zymolyase to digest away the membrane sac surrounding the ascospores of the asci. Using micromanipulation with a microneedle under a dissection microscope one can pick up individual asci and separate and relocate the four ascopores. Dissected asci are grown for several days and tested for the markers or alleles of interest by replica plating onto appropriate selective media. PMID:19455096

Morin, Audrey; Moores, Adrian W; Sacher, Michael

2009-05-19

193

Phosphoproteome Analysis of Functional Mitochondria Isolated from Resting Human Muscle Reveals Extensive Phosphorylation of Inner Membrane Protein Complexes and Enzymes*  

PubMed Central

Mitochondria play a central role in energy metabolism and cellular survival, and consequently mitochondrial dysfunction is associated with a number of human pathologies. Reversible protein phosphorylation emerges as a central mechanism in the regulation of several mitochondrial processes. In skeletal muscle, mitochondrial dysfunction is linked to insulin resistance in humans with obesity and type 2 diabetes. We performed a phosphoproteomics study of functional mitochondria isolated from human muscle biopsies with the aim to obtain a comprehensive overview of mitochondrial phosphoproteins. Combining an efficient mitochondrial isolation protocol with several different phosphopeptide enrichment techniques and LC-MS/MS, we identified 155 distinct phosphorylation sites in 77 mitochondrial phosphoproteins, including 116 phosphoserine, 23 phosphothreonine, and 16 phosphotyrosine residues. The relatively high number of phosphotyrosine residues suggests an important role for tyrosine phosphorylation in mitochondrial signaling. Many of the mitochondrial phosphoproteins are involved in oxidative phosphorylation, tricarboxylic acid cycle, and lipid metabolism, i.e. processes proposed to be involved in insulin resistance. We also assigned phosphorylation sites in mitochondrial proteins involved in amino acid degradation, importers and transporters, calcium homeostasis, and apoptosis. Bioinformatics analysis of kinase motifs revealed that many of these mitochondrial phosphoproteins are substrates for protein kinase A, protein kinase C, casein kinase II, and DNA-dependent protein kinase. Our results demonstrate the feasibility of performing phosphoproteome analysis of organelles isolated from human tissue and provide novel targets for functional studies of reversible phosphorylation in mitochondria. Future comparative phosphoproteome analysis of mitochondria from healthy and diseased individuals will provide insights into the role of abnormal phosphorylation in pathologies, such as type 2 diabetes.

Zhao, Xiaolu; Leon, Ileana R.; Bak, Steffen; Mogensen, Martin; Wrzesinski, Krzysztof; H?jlund, Kurt; Jensen, Ole N?rregaard

2011-01-01

194

Phosphoproteomic analysis reveals site-specific changes in GFAP and NDRG2 phosphorylation in frontotemporal lobar degeneration  

PubMed Central

Frontotemporal lobar degeneration (FTLD) is a progressive neurodegenerative disease characterized by behavioral abnormalities, personality changes, language dysfunction, and can co-occur with the development of motor neuron disease. One major pathological form of FTLD is characterized by intracellular deposition of ubiquitinated and phosphorylated TAR DNA binding protein-43 (TDP-43), suggesting that dysregulation in phosphorylation events may contribute to disease progression. However, to date systematic analysis of the phosphoproteome in FTLD brains has not been reported. In this study we employed immobilized metal affinity chromatography (IMAC) followed by liquid chromatography-tandem mass spectrometry (LC-MS/MS) to identify phosphopeptides from FTLD and age-matched control postmortem human brain tissue. Using this approach we identified 786 phosphopeptides in frontal cortex (control and FTLD), in which the population of phosphopeptides represented approximately 50% of the total peptides analyzed. Label free quantification using spectral counts revealed six proteins with significant changes in the FTLD phosphoproteome. N-myc-downstream regulated gene 2 (NDRG2) and glial fibrillary acidic protein (GFAP) had an increased number of phosphospectra in FTLD, whereas microtubule associated protein 1A (MAP1A), reticulon 4 (RTN4; also referred to as neurite outgrowth inhibitor (Nogo)), protein kinase C gamma (PRKCG), and heat shock protein 90kDa alpha, class A member 1(HSP90AA1) had significantly fewer phosphospectra compared to control brain. To validate these differences, we examined NDRG2 phosphorylation in FTLD brain by immunoblot analyses, and using a phosphoserine-13 (pSer13) GFAP monoclonal antibody we show an increase in pSer13 GFAP levels by immunoblot concomitant with increased overall GFAP levels in FTLD cases. These data highlight the utility of combining proteomic and phosphoproteomic strategies to characterize postmortem human brain tissue.

Herskowitz, Jeremy H.; Seyfried, Nicholas T.; Duong, Duc M.; Xia, Qiangwei; Rees, Howard D.; Gearing, Marla; Peng, Junmin; Lah, James J.; Levey, Allan I.

2010-01-01

195

A dissecting competition for medical students.  

PubMed

After repeated requests from medical students for more cadaver dissection opportunities, a voluntary dissecting "competition" was initiated for the third year medical students in 2006. This has been held annually on five occasions since, offering up to 30 dissection stations and accommodating an average of 53 students (range 40-66) per year, representing about 20-25% of the total class. Material is standardized to distal upper or lower limb specimens, each of which is dissected by one or two students during a single weekend day. Participants are required to complete their dissection in about six hours and present an appropriately labeled display together with a 300 word abstract, emphasizing clinical relevance. Dissections are judged on presentation, accuracy of identification and labeling, and relevance to the clinical abstract, taking into account the technical difficulty of the particular dissection. Judging from successive annual uptake of places and informal feedback, this is not only a popular event allowing students to focus creatively on producing a clinically relevant dissection in a relaxed learning environment but also of educational value. An unexpected outcome has been the production of many specimens suitable as prosections for future classes. A dissecting competition may be a useful method of stimulating learning for medical students interested in undertaking further dissection but it requires appropriate staff commitment and a supply of suitable cadaver specimens. PMID:22213677

Samalia, Latika; Stringer, Mark D

2011-12-29

196

Analysis of the Rana catesbeiana tadpole tail fin proteome and phosphoproteome during T3-induced apoptosis: identification of a novel type I keratin  

Microsoft Academic Search

BACKGROUND: Thyroid hormones (THs) are vital in the maintenance of homeostasis and in the control of development. One postembryonic developmental process that is principally regulated by THs is amphibian metamorphosis. This process has been intensively studied at the genomic level yet very little information at the proteomic level exists. In addition, there is increasing evidence that changes in the phosphoproteome

Dominik Domanski; Caren C Helbing

2007-01-01

197

A comparison of the effects of animal dissection and a computer simulation dissection program on students' knowledge of frog anatomy and attitudes toward dissection  

Microsoft Academic Search

The purpose of this study was to examine the effectiveness of computer-simulated dissection versus the effectiveness of true dissection related to student achievement and attitude. Student achievement was measured by post-dissection and delayed post-dissection tests which measured students' knowledge on frog anatomy. Students' attitudes were measured by pre-dissection and post-dissection attitude surveys. The sample used consisted of 115 high school

Isabella Michel-Clark

2003-01-01

198

Vertebral artery dissection associated with sildenafil abuse.  

PubMed

We present a 49-year-old male who suffered a cerebellar infarction due to a vertebral artery dissection. The patient had taken sildenafil daily for at least 2 years for sexual enhancement. There was no sexual intercourse or traumatic event prior to symptom onset. Sildenafil intake has been associated with aortic dissection and, in the light of this report, we suggest that chronic sildenafil intake could be a risk factor for arterial dissection. PMID:23454143

Dersch, Rick; Anastasopoulos, Constantin; Hader, Claudia; Stich, Oliver

2013-02-27

199

Aortic dissection presenting as pleural effusion  

PubMed Central

Aortic dissection is a life threatening emergency. This case illustrates the unusual way an aortic dissection can present. This patient presented with sharp, left interscapular pain, which subsided after a while and left-sided pleural effusion. Further investigations revealed that this was a case of thoracic aortic dissection with a leak into pleural space. She underwent thoracic endovascular aortic repair with stent graft insertion.

Somasamudra, Pramod; Smith, Ed; Tandan, Ronja

2011-01-01

200

[Progress in genetic study of aortic dissection].  

PubMed

Genetic study can provide important insight into the etiology of aortic dissection. To explore the pathogenesis and natural history of aortic dissection, a number of genes have been identified through microarray chip screening and undergone testing of polymorphisms to find mutations strongly associated with the disease. The results suggested aortic dissection to be a multi-gene disorder. Multiple genes probably work together to promote its development. Several diseases with a genetic predisposition are closely connected with aortic dissection, which also implied a role of genetic changes and malfunction in this disease. PMID:23926011

Li, Yongsheng; Fu, Weiguo; Dong, Zhihui; Wang, Lixin; Wang, Yuqi

2013-08-01

201

Extracranial vertebral artery dissection: nine cases.  

PubMed

Nine patients (six men, three women) with extracranial vertebral artery dissection are described. Their mean age was 39.1 years (range 17-66). In four cases dissection was "spontaneous"; in the other five cases there was a history of trivial trauma. Three patients had fibromuscular dysplasia, two were migraineurs, one had elastorrhexis. Treatment varied. Six received heparin, three acetylsalicylic acid or ticlopidine. Eight had good recovery. Two patients experienced recurrence when stopping acetylsalicylic acid. The pathogenesis of dissections and the distinction between spontaneous dissections and those associated with minor trauma are discussed. PMID:1512608

Josien, E

1992-07-01

202

Use of 32P to Study Dynamics of the Mitochondrial Phosphoproteome  

PubMed Central

Protein phosphorylation is a well characterized regulatory mechanism in the cytosol, but remains poorly defined in the mitochondrion. In this study, we characterized the use of 32P-labeling to monitor the turnover of protein phosphorylation in the heart and liver mitochondria matrix. The 32P labeling technique was compared and contrasted to Phos-tag protein phosphorylation fluorescent stain and 2D isoelectric focusing. Of the 64 proteins identified by MS spectroscopy in the Phos-Tag gels, over 20 proteins were correlated with 32P labeling. The high sensitivity of 32P incorporation detected proteins well below the mass spectrometry and even 2D gel protein detection limits. Phosphate-chase experiments revealed both turnover and phosphate associated protein pool size alterations dependent on initial incubation conditions. Extensive weak phosphate/phosphate metabolite interactions were observed using non-disruptive native gels, providing a novel approach to screen for potential allosteric interactions of phosphate metabolites with matrix proteins. We confirmed the phosphate associations in Complexes V and I due to their critical role in oxidative phosphorylation and to validate the 2D methods. These complexes were isolated by immunocapture, after 32P labeling in the intact mitochondria, and revealed 32P-incorporation for the ?, ?, ?, OSCP, and d subunits in Complex V and the 75kDa, 51kDa, 42kDa, 23kDa, and 13a kDa subunits in Complex I. These results demonstrate that a dynamic and extensive mitochondrial matrix phosphoproteome exists in heart and liver.

Aponte, Angel M.; Phillips, Darci; Hopper, Rachel K.; Johnson, D. Thor; Harris, Robert A.; Blinova, Ksenia; Boja, Emily S.; French, Stephanie; Balaban, Robert S.

2009-01-01

203

Change of carbon source causes dramatic effects in the phospho-proteome of the archaeon Sulfolobus solfataricus.  

PubMed

Protein phosphorylation is known to occur in Archaea. However, knowledge of phosphorylation in the third domain of life is rather scarce. Homology-based searches of archaeal genome sequences reveals the absence of two-component systems in crenarchaeal genomes but the presence of eukaryotic-like protein kinases and protein phosphatases. Here, the influence of the offered carbon source (glucose versus tryptone) on the phospho-proteome of Sulfolobus solfataricus P2 was studied by precursor acquisition independent from ion count (PAcIFIC). In comparison to previous phospho-proteome studies, a high number of phosphorylation sites (1318) located on 690 phospho-peptides from 540 unique phospho-proteins were detected, thus increasing the number of currently known archaeal phospho-proteins from 80 to 621. Furthermore, a 25.8/20.6/53.6 Ser/Thr/Tyr percentage ratio with an unexpectedly high predominance of tyrosine phosphorylation was detected. Phospho-proteins in most functional classes (21 out of 26 arCOGs) were identified, suggesting an important regulatory role in S. solfataricus. Focusing on the central carbohydrate metabolism in response to the offered carbon source, significant changes were observed. The observed complex phosphorylation pattern hints at an important physiological function of protein phosphorylation in control of the central carbohydrate metabolism, which might particularly operate in channeling carbon flux into the respective metabolic pathways. PMID:22639831

Esser, D; Pham, T K; Reimann, J; Albers, S V; Siebers, B; Wright, P C

2012-09-14

204

Analysis of the serine/threonine/tyrosine phosphoproteome of the pathogenic bacterium Listeria monocytogenes reveals phosphorylated proteins related to virulence.  

PubMed

Phosphorylation is the most common and widely studied post-translational protein modification in bacteria. It plays an important role in all kinds of cellular processes and controls key regulatory mechanisms, including virulence in certain pathogens. To gain insight into the role of protein phosphorylation in the pathogen Listeria monocytogenes, the serine (Ser), threonine (Thr) and tyrosine (Tyr) phosphoproteome of this bacterium was determined. We used the "gel free" proteomic approach with high accuracy mass spectrometry after enrichment of phosphopeptides. A total of 143 sites of phosphorylation were clearly identified, on 155 unique peptides of 112 phosphoproteins. The Ser/Thr/Tyr phosphorylation site distribution was 93:43:7. All identified phosphopeptides are monophosphorylated, except one and many identified phosphoproteins are related to virulence, translation, phosphoenolpyruvate:sugar phosphotransferase system, glycolysis and stress response. A description of these phosphoproteins is provided together with a comparison of the phosphosites in the L. monocytogenes proteins and in their homologues of other bacteria for which the phosphoproteome has been determined. Compared with the previous studies, we noticed a more extended conservation of the phosphorylation sites in glycolytic enzymes as well as ribosomal proteins. PMID:21956863

Misra, Sandeep K; Milohanic, Eliane; Aké, Francine; Mijakovic, Ivan; Deutscher, Josef; Monnet, Véronique; Henry, Céline

2011-09-29

205

Combination of Multistep IMAC Enrichment with High-pH Reverse Phase Separation for In-Depth Phosphoproteomic Profiling.  

PubMed

Typical mass spectrometric phosphoproteome studies are complicated by the need for large amounts of starting material and extensive sample preparation to ensure sufficient phosphopeptide identifications. In this paper, we present a novel strategy to perform optimized multistep IMAC enrichment from whole cell lysates followed by high-pH reverse phase fractionation (multi-IMAC-HLB; HLB means hydrophilic-lipophilic-balanced reversed-phase cartridge). The peptide-to-IMAC ratio was optimized to maximize IMAC performance, while multistep IMAC enrichment enabled improved phosphopeptide acquisition. The addition of the HLB step further fractionates the IMAC enriched phosphopeptides while desalting the samples, which dramatically reduces the sample manipulation time and sample loss compared to other popular strategies. We compared the phosphopeptide identification results of the multi-IMAC-HLB method with 3 mg of starting material to the well-established SCX-IMAC method with 15 mg of starting material. We identified 8969 unique phosphopeptides with the multi-IMAC-HLB method, compared to 5519 unique phosphopeptides identified with the SCX-IMAC method, an increase of 62.5%. The increase in the numbers of identified phosphopeptides is due to the increase in the ratio of identified phosphopeptides out of all detected peptides, 70.5% with multi-IMAC-HLB method compared to 32.3% with the SCX-IMAC method. Multi-IMAC-HLB is a robust and efficient method for in-depth phosphoproteomic research. PMID:23927012

Yue, Xiao-Shan; Hummon, Amanda B

2013-08-08

206

Post-operative morbidity following paediatric tonsillectomy; a comparison of bipolar diathermy dissection and blunt dissection  

Microsoft Academic Search

In a prospective study of 76 children aged between 18 months and 13 years, 40 children underwent tonsillectomy using the traditional blunt dissection technique with bipolar diathermy to establish haemostasis while 36 children underwent tonsillectomy where bipolar diathermy alone was used to dissect out the tonsils. Blood loss was significantly reduced in the diathermy dissection group (10.5 ml ± 2.05,

F. B. MacGregor; D. M. Albert; A. K. Bhattacharyya

1995-01-01

207

Spontaneous Cervical Artery Dissection: The Borgess Classification  

PubMed Central

Background and Purpose: The pathogenesis of spontaneous cervical artery dissections (sCAD) and its best medical treatment are debated. This may be due to a lack of clear classification of sCAD. We propose the new Borgess classification of sCAD, based on the presence or absence of intimal tear as depicted on imaging studies and effect on blood flow. Materials and Methods: This is a single-center investigator-initiated registry on consecutive patients treated for sCAD. In the Borgess classification, type I dissections have intact intima and type II dissections have an intimal tear. Results: Forty-four patients and 52 dissected arteries were found. Forty-nine of 52 dissections (93%) were treated with dual anti-platelet therapy. Twenty-one of 52 dissections were type I; 31 were type II. Type I dissections were more likely to present with ischemic symptoms [stroke, transient ischemic attack (TIA)] (p?=?0.001). More type I dissections occurred in the vertebral artery, while more type II dissections occurred in the internal carotid artery (p?dissections were more likely to heal than type II (p?dissection types in the Borgess classification appear to relate to clinical presentation and rate of healing, making the classification useful in clinical management. Dual anti-platelet therapy for sCAD seems to have a very low risk of subsequent stroke; however, a large prospective study is needed to investigate the best treatment.

Perry, Brandon C.; Al-Ali, Firas

2013-01-01

208

Virtual temporal bone dissection: a case study  

Microsoft Academic Search

The Temporal Bone Dissection Simulator is an ongoing research project for the construction of a synthetic environment suitable for virtual dissection of human temporal bone and related anatomy. Funded by the National Institute on Deafness and Other Communication Disorders (NIDCD), the primary goal of this project is to provide a safe, robust, and cost-effective virtual environment for learning the anatomy

Jason Bryan; Don Stredney; Gregory J. Wiet; Dennis Sessanna

2001-01-01

209

Objecting To Dissection: A College Student's Handbook.  

ERIC Educational Resources Information Center

|In a number of states, students from kindergarten through high school have won the right to refuse to dissect or kill animals and the right to substitute an alternative project. This booklet was designed to help college science students take an ethical stand by refusing to participate in dissection exercises. The booklet begins with an overview…

National Anti-Vivisection Society, Chicago, IL.

210

Vertebral artery dissection causing stroke in sport  

Microsoft Academic Search

Five cases of vertebral arterial dissection occurring in sport are presented. These cases emphasise the diagnostic and management difficulties in this setting. Stroke in sport, although uncommon, is predominantly due to arterial dissection in either the vertebral or carotid arteries. Physicians involved in athlete care need to be aware of this diagnosis.

Paul McCrory

2000-01-01

211

Modeling the propagation of arterial dissection  

Microsoft Academic Search

Arterial dissections are frequently observed in clinical practice and during road traffic accidents. In particular, the lamellarly arrangement of elastin, collagen, in addition to smooth muscle cells in the middle arterial layer, the media, favors dissection failure. Experimental studies and related biomechanical models are rare in the literature. Finite strain kinematics is employed, and the discontinuity in the displacement field

T. Christian Gasser; Gerhard A. Holzapfel

2006-01-01

212

Extracranial vertebral artery dissection: nine cases  

Microsoft Academic Search

Nine patients (six men, three women) with extracranial vertebral artery dissection are described. Their mean age was 39.1 years (range 17–66). In four cases dissection was “spontaneous”; in the other five cases there was a history of trivial trauma. Three patients had fibromuscular dysplasia, two were migraineurs, one had elastorrhexis. Treatment varied. Six received heparin, three acetylsalicylic acid or ticlopidine.

E. Josien

1992-01-01

213

Surgical Management of Spontaneous Coronary Artery Dissection  

PubMed Central

Spontaneous coronary artery dissection, which causes acute coronary syndrome and can result in sudden death, is rare; but its true incidence is underestimated, since most patients die suddenly, without diagnosis. The aim of this study was to show the importance of prompt diagnosis and treatment. In reviewing the records of 5,000 consecutive patients who underwent coronary angiography between January 2001 and August 2006, we found 6 cases of spontaneous coronary artery dissection (an incidence rate of 0.12%). Five patients presented with left main coronary artery dissection and 1 patient, with right coronary artery dissection. Angioplasty with stenting failed in the patient with right coronary artery dissection. Coronary artery bypass surgery was performed in all patients. The patient with right coronary artery dissection died of sepsis on the 30th postoperative day. The other 5 patients (83.3%) are still free of symptoms, and they had negative results on stress tests at the 6- and 12-month follow-up visits after coronary artery bypass surgery. The clinical presentation of spontaneous left main coronary artery dissection was similar to that of atherosclerotic disease. However, early diagnosis of spontaneous coronary artery dissection by means of coronary angiography is of paramount importance, because urgent coronary artery bypass grafting can be lifesaving.

Unal, Mehmet; Korkut, Ali Kubilay; Kosem, Mesut; Ertunc, Vedat; Ozcan, Mustafa; Caglar, Nizamettin

2008-01-01

214

Quick Dissection of the Segmental Bronchi  

ERIC Educational Resources Information Center

|Knowledge of the three-dimensional anatomy of the bronchopulmonary segments is essential for respiratory medicine. This report describes a quick guide for dissecting the segmental bronchi in formaldehyde-fixed human material. All segmental bronchi are easy to dissect, and thus, this exercise will help medical students to better understand the…

Nakajima, Yuji

2010-01-01

215

Neck Dissection Through a Facelift Incision  

PubMed Central

Obectives/Hypothesis To determine the feasibility and safety of neck dissection through a facelift incision. Study Design Prospective case series. Methods Cadavers and live subjects underwent neck dissection using a facelift incision with and without endoscopic assistance. In the live facelift neck dissection (FLND), the preoperative surgical indications, staging, adjuvant therapy, intraoperative technical procedure, pathology reports on lymph nodes, and short-term outcomes were reviewed. Results FLND was successfully performed in four cadavers and four live subjects, including selective (less than five neck levels removed) and comprehensive (levels I–V removed) neck dissections. All levels were accessible through this approach, with additional retraction required for levels I and IV. Endoscopic assistance was required in one neck dissection for adequate visualization. Short-term complications and number of excised lymph nodes were comparable to those from traditional neck dissection approaches. Conclusions Open neck dissection through a facelift incision is feasible and offers an alternate approach to traditional incisions. This can be performed without requiring robotic assistance and with endoscopic assistance only in certain cases. Endoscopic assistance can offer enhanced visualization of the surgical field and complement open direct approaches in neck dissection. Although FLND offers improved cosmetic outcomes when compared to those of traditional neck incisions, further study is required to determine its efficacy and indications.

Melvin, Thuy-Anh N.; Eliades, Steven J.; Ha, Patrick K.; Fakhry, Carole; Saunders, John M.; Califano, Joseph A.; Blanco, Ray G. F.

2013-01-01

216

Objecting To Dissection: A College Student's Handbook.  

ERIC Educational Resources Information Center

In a number of states, students from kindergarten through high school have won the right to refuse to dissect or kill animals and the right to substitute an alternative project. This booklet was designed to help college science students take an ethical stand by refusing to participate in dissection exercises. The booklet begins with an overview of…

National Anti-Vivisection Society, Chicago, IL.

217

Surgical management of spontaneous coronary artery dissection.  

PubMed

Spontaneous coronary artery dissection, which causes acute coronary syndrome and can result in sudden death, is rare; but its true incidence is underestimated, since most patients die suddenly, without diagnosis. The aim of this study was to show the importance of prompt diagnosis and treatment. In reviewing the records of 5,000 consecutive patients who underwent coronary angiography between January 2001 and August 2006, we found 6 cases of spontaneous coronary artery dissection (an incidence rate of 0.12%). Five patients presented with left main coronary artery dissection and 1 patient, with right coronary artery dissection. Angioplasty with stenting failed in the patient with right coronary artery dissection. Coronary artery bypass surgery was performed in all patients. The patient with right coronary artery dissection died of sepsis on the 30th postoperative day. The other 5 patients (83.3%) are still free of symptoms, and they had negative results on stress tests at the 6- and 12-month follow-up visits after coronary artery bypass surgery. The clinical presentation of spontaneous left main coronary artery dissection was similar to that of atherosclerotic disease. However, early diagnosis of spontaneous coronary artery dissection by means of coronary angiography is of paramount importance, because urgent coronary artery bypass grafting can be lifesaving. PMID:19156232

Unal, Mehmet; Korkut, Ali Kubilay; Kosem, Mesut; Ertunc, Vedat; Ozcan, Mustafa; Caglar, Nizamettin

2008-01-01

218

Vertebral artery dissection with amphetamine abuse  

Microsoft Academic Search

Vertebral artery dissection is an important cause of disabling stroke in young adults, recognition of its presenting features and risk factors is paramount for expeditious diagnosis and preventive treatment. Numerous risk factors for vertebral artery dissection have been reported; trauma is the most common. This case report describes a patient with amphetamine abuse, who had posterior circulation stroke from vertebral

Osama O. Zaidat; Jeffery Frank

2001-01-01

219

Beyond Dissection: Innovative Tools for Biology Education.  

ERIC Educational Resources Information Center

|This catalog lists resources available for classroom use in teaching about anatomy and physiology which are alternatives to dissection. The entries are provided under three main categories: (1) Whole Animal Dissection/Vivisection; (2) Animal Organ or System Anatomy and Physiology; and (3) Other, including animal behavior, biotechnology,…

Larson, Sandra, Ed.

220

Superselective neck dissection: rationale, indications, and results.  

PubMed

It has been established that an appropriately indicated selective neck dissection can achieve the same oncologic results as more extensive dissections. An even more modified selective neck dissection, termed superselective neck dissection, involves the compartmental removal of the fibrofatty tissue contents within the defined boundaries of two or fewer contiguous neck levels. Evidence from retrospective studies suggests that superselective neck dissection (SSND) is oncologically sound for two indications: elective treatment of the clinically N0 neck and salvage treatment of persistent lymph node disease after chemoradiotherapy. While there is broader support for the former scenario, evidence that SSND may constitute optimal treatment in the latter is in conformity with the trend toward developing surgical techniques that provide better functional outcomes without compromising efficacy. PMID:23321797

Suárez, Carlos; Rodrigo, Juan P; Robbins, K Thomas; Paleri, Vinidh; Silver, Carl E; Rinaldo, Alessandra; Medina, Jesus E; Hamoir, Marc; Sanabria, Alvaro; Mondin, Vanni; Takes, Robert P; Ferlito, Alfio

2013-01-16

221

Bilateral renal artery dissection following extreme exertion.  

PubMed

Dissection of a renal artery is rare and is usually associated with underlying arterial disease. Bilateral renal artery dissection following extreme exertion is exceptionally uncommon, and thus presents a diagnostic challenge. We report a case of a middle-aged, otherwise healthy man who presented to the hospital with left flank pain after a long bicycling trip. Initial laboratory tests and urinalysis were normal. Careful review of a contrast-enhanced computed tomography angiogram (CTA) with 3D reconstruction revealed bilateral segmental renal artery dissection and thrombosis with corresponding renal infarcts. He was treated medically and rapidly recovered. PMID:21955870

Baroudi, S; Bastani, B; Balci, N; Bieneman, B K; Sobti, P; Kudva, G C

2011-10-01

222

A phosphoproteomics approach to identify candidate kinase inhibitor pathway targets in lymphoma-like primary cell lines.  

PubMed

Mass spectrometry-based technologies are increasingly utilized in drug discovery. Phosphoproteomics in particular has allowed for the efficient surveying of phosphotyrosine signaling pathways involved in various diseases states, most prominently in cancer. We describe a phosphotyrosine-based proteomics screening approach to identify signaling pathways and tyrosine kinase inhibitor targets in highly tumorigenic human lymphoma-like primary cells. We identified several receptor tyrosine kinase pathways and validated SRC family kinases (SFKs) as potential drug targets for targeted selection of small molecule inhibitors. BMS-354825 (dasatinib) and SKI-606 (bosutinib), second and third generation clinical SFK/ABL inhibitors, were found to be potent cytotoxic agents against tumorigenic cells with low toxicity to normal pediatric stem cells. Both SFK inhibitors reduced ERK1/2 and AKT phosphorylation and induced apoptosis. This study supports the adaptation of high-end mass spectrometry techniques for the efficient identification of candidate tyrosine kinases as novel therapeutic targets in primary cancer cell lines. PMID:23701117

Vojvodic, Miliana; Hansford, Loen M; Morozova, Olena; Blakely, Kim M; Taylor, Paul; Fathers, Kelly E; Moffat, Jason; Marra, Marco; Smith, Kristen M; Moran, Michael F; Kaplan, David R

2013-12-01

223

The Phosphoproteomes of Plasmodium falciparum and Toxoplasma gondii reveal unusual adaptations within and beyond the parasites' boundaries  

PubMed Central

Summary Plasmodium falciparum and Toxoplasma gondii are obligate intracellular apicomplexan parasites that rapidly invade and extensively modify host cells. Protein phosphorylation is one mechanism by which these parasites can control such processes. Here we present a phosphoproteome analysis of peptides enriched from schizont stage P. falciparum and T. gondii tachyzoites that are either “intracellular” or purified away from host material. Using liquid chromatography and tandem mass-spectrometry we identified over 5,000 and 10,000 previously unknown phosphorylation sites in P. falciparum and T. gondii respectively, revealing that protein phosphorylation is an extensively used regulation mechanism both within and beyond parasite boundaries. Unexpectedly both parasites have phosphorylated tyrosines and P. falciparum has unusual phosphorylation motifs that are apparently shaped by its A:T-rich genome. This dataset provides important information on the role of phosphorylation in the host-pathogen interaction, and clues to the evolutionary forces operating on protein phosphorylation motifs in both parasites.

Treeck, Moritz; Sanders, John L.; Elias, Joshua E.; Boothroyd, John C.

2012-01-01

224

Training in endoscopic submucosal dissection.  

PubMed

Endoscopic submucosal dissection (ESD) represents an important advancement in the therapy of early neoplastic gastrointestinal lesions by providing higher en-bloc curative resection rate with lower recurrence compared to endoscopic mucosal resection (EMR) and by sparing the involved organ and protecting patient's quality of life. Despite these advantages ESD is associated with long procedure times and a higher rate of complications, making ESD a challenging procedure which requires advanced endoscopic skills. Thus, there has been a recognized need for structured training system for ESD to enhance trainee experience and, to reduce the risks of complications and inadequate treatment. ESD has a very flat learning curve. However, we do not have uniformly accepted benchmarks for competency. Nevertheless, it appears that, in Japan, more than 30 supervised gastric ESD procedures are required to achieve technical proficiency and minimize complications. A number of training algorithms have been proposed in Japan with the aim to standardize ESD training. These algorithms cannot be directly applied in the West due to substantial differences including the availability of highly qualified mentors, the type of pathology seen, choice of devices, and trainee's background. We propose a training algorithm for Western physicians which integrates both hands-on training courses, animal model work as well as visits to expert centers. No specific preceptor training programs have been yet developed but there is a consensus that these programs are important for permeation of ESD worldwide. PMID:23951392

Coman, Roxana M; Gotoda, Takuji; Draganov, Peter V

2013-08-16

225

Debates on Colorectal Endoscopic Submucosal Dissection - Traction for Effective Dissection: Gravity Is Enough  

PubMed Central

Colorectal endoscopic submucosal dissection (ESD) still remains a technically difficult procedure. The maintenance of tissue tension and good submucosal exposure during dissection is one of the most important factors for an effective and safe dissection. Although various traction methods have been developed, traction by gravity is one of the most useful method for colorectal ESD. Traction using adjunctive devices can thus be reserved for extremely difficult cases or for endoscopists in their learning periods for colorectal ESD.

2013-01-01

226

Dissecting aortic aneurysm in maintenance hemodialysis patients.  

PubMed

The dissecting aortic aneurysm (DAA) is a rare pathology that may result in fatal outcome. We report follow up of three cases of DAA patients undergoing maintenance hemo-dialysis who were managed conservatively. PMID:19861869

Ounissi, M; Goucha, R; Hedri, H; Hamida, F Ben; Abderrahim, E; El Younsi, F; Abdallah, T Ben; Maiz, H Ben; Kheder, A

2009-11-01

227

Efficient tissue gluing in aortic dissection  

Microsoft Academic Search

The authors' method for uniting the dissected aortic wall layers with the help of gelatine-resorcinol adhesive is described focusing on special instruments used in this conjunction. (Eur J Cardio-thorac Surg (1994) 8:160-1611

H. G. Borst; J. Laas; B. Biihner

1994-01-01

228

Animal Rights Groups Target High School Dissection.  

ERIC Educational Resources Information Center

|Two groups leading the charge against dissection are People for the Ethical Treatment of Animals (PETA) and the Student Action Corps for Animals (SACA). Protests by student and community members remain the movement's strongest weapon. (MLF)|

Trotter, Andrew

1992-01-01

229

An unusual case of carotid dissection.  

PubMed

Carotid dissection is a rare, but potentially fatal, cause of ischaemic stroke in young patients. It occurs when a small tear forms in the tunica intima of the arterial wall creating a space between the inner and outer layers of the vessel where blood can enter and form a haematoma. This can cause a stenosis or complete occlusion. Thromboembolic events are thought to be the cause of infarction in the majority of cases of stroke, rather than haemodynamic insufficiency, in patients with carotid dissection. Although traditionally thought to be most commonly caused by head or neck trauma, spontaneous carotid dissection is now an increasingly recognised cause of stroke in young patients. Clinical signs can often be subtle, with mild cerebral or cranial nerve dysfunction. Here, a case is reported of a spontaneous internal carotid artery dissection in a previously well 38-year-old man. An appropriate imaging modality is important to confirm the diagnosis before commencing anticoagulation treatment. PMID:20562155

Mazhary, S; Dev, S; Mentzer, A

2010-06-01

230

Spontaneous aortic dissecting hematoma in two dogs.  

PubMed

This report describes 2 cases of spontaneous aortic dissecting hematoma in young Border Collie and Border Collie crossbred dogs. Histology was performed in one of the cases involving an unusual splitting of the elastin present within the wall of the aorta, consistent with elastin dysplasia as described in Marfan syndrome in humans. The first case involved a young purebred Border Collie that died suddenly and the second case involved a Border Collie crossbred dog that died after a 1-month history of seizures. Gross lesions included pericardial tamponade with dissection of the ascending aorta in the former case and thoracic cavity hemorrhage, mediastinal hematoma, and aortic dissection in the latter. Histologic lesions in the case of the Border Collie crossbred dog included a dissecting hematoma of the ascending aorta with elastin dysplasia and right axillary arterial intimal proliferation. PMID:16312247

Boulineau, Theresa Marie; Andrews-Jones, Lydia; Van Alstine, William

2005-09-01

231

Bilateral spontaneous dissection of extracranial vertebral arteries  

Microsoft Academic Search

A previously healthy 35-year-old man suddenly developed vertebrobasilar ischaemia while playing tennis. Cerebral arteriography revealed a dissecting aneurysm of the cervical portion of both vertebral arteries. The neurological deficit and the angiographic features resolved with anticoagulant treatment alone. Only 15 patients with non-traumatic extracranial vertebral artery dissection have been previously reported. It is necessary to recognize the condition very quickly,

D. Leys; F. Lesoin; J. P. Pruvo; G. Gozet; M. Jomin; H. Petit

1987-01-01

232

Pulmonary artery dissection: echocardiographic findings and diagnosis.  

PubMed

Pulmonary artery dissection is a rare but life-threatening event, predisposing to sudden cardiac death or cardiogenic shock. It is often associated with underlying congenital disorders predisposing to pulmonary hypertension. Rarely, it is diagnosed by echocardiography or other image techniques. We present a case report of a pulmonary artery dissection, diagnosed primarily by echocardiography. The patient died soon after refusing any interventional approach after a short period under medication. PMID:12848882

Areco, Daniel; Pizzano, Nelson

2003-05-01

233

Managing Dissections of the Thoracic Aorta  

PubMed Central

Thoracic aortic dissection is associated with substantial morbidity and mortality, and it requires timely and accurate diagnosis and treatment. Long-term antihypertensive therapy remains critical for the treatment of this disease. Surgical intervention, although still a formidable undertaking, has evolved to better address both acute and chronic dissection, and the results have improved. Basic and clinical research, as well as technological advances, have increased our understanding of this challenging disease state.

WONG, DANIEL R.; LEMAIRE, SCOTT A.; COSELLI, JOSEPH S.

2010-01-01

234

Spontaneous Mirror Dissections of Cervicocephalic Arteries  

PubMed Central

Summary While so-called twin or mirror aneurysms constitute an established subgroup of multiple aneurysms, simultaneous spontaneous mirror dissections of cervicocephalic artery have not yet been reported as a particular entity. Among the patients treated at our institution since 1989, we identified 74 patients with spontaneous, nontraumatic dissections. Six of these cases presented with simultaneous bilateral dissections and four of the six patients had mirror dissections. Acute or chronic headache was present in all four cases. Additional clinical presentations consisted of impaired consciousness, cranial nerve palsy, and tinnitus. Angiography revealed irregular stenosis, dilatation or aneurysms located in the cervical ICA (internal carotid artery), VA (vertebral artery), or MCA (middle cerebral artery) without evident location bias. Although mirror dissections seems to be an exceptional finding, they may shed light on the vulnerability of different arterial segments to specific diseases. Similar to arterial aneurysm formation, pathogenesis of mirror dissection may involve an underlying "shared defect" in the endothelial cells, since these cells demonstrate a bilateral distribution during embryological development. This particular distribution therefore also provides a chronicle trail of the first trigger striking during embryonic development and demonstrates the segmental vulnerability to highly specific triggers.

Zhao, W.Y.; Krings, T.; Alvarez, H.; Ozanne, A.; Holmin, S.; Lasjaunias, P.L.

2006-01-01

235

Recurrent post-partum coronary artery dissection  

PubMed Central

Coronary artery dissection is a rare but well-described cause for myocardial infarction during the post-partum period. Dissection of multiple coronary arteries is even less frequent. Here we present a case of recurrent post-partum coronary artery dissections. This unusual presentation poses unique problems for management. A 35 year-old female, gravida 3 para 2, presented with myocardial infarction 9 weeks and 3 days post-partum. Cardiac catheterization demonstrated left anterior descending (LAD) dissection but an otherwise normal coronary anatomy. The lesion was treated with four everolimus eluting stents. Initially the patient made an unremarkable recovery until ventricular fibrillation arrest occurred on the following day. Unsynchronized cardioversion restored a normal sinus rhythm and repeat catheterization revealed new right coronary artery (RCA) dissection. A wire was passed distally, but it was unclear whether this was through the true or false lumen and no stents could be placed. However, improvement of distal RCA perfusion was noted on angiogram. Despite failure of interventional therapy the patient was therefore treated conservatively. Early operation after myocardial infarction has a significantly elevated risk of mortality and the initial dissection had occurred within 24 hours. This strategy proved successful as follow-up transthoracic echocardiography after four months demonstrated a preserved left ventricular ejection fraction of 55-60% without regional wall motion abnormalities. The patient remained asymptomatic from a cardiac point of view.

2010-01-01

236

Acute aortic dissection in China.  

PubMed

The clinical profiles and outcomes of acute aortic dissection (AAD) have not been evaluated in China. We retrospectively analyzed, from January 1, 2008 to December 31, 2011, the data from 1,812 patients (mean age 51.1 ± 10.9 years; 77.5% men) with AAD (726 with type A and 1,086 with type B) from 19 large hospitals. Most patients had hypertension and presented with an abrupt onset of chest and/or back pain. Patients with type A AAD were more likely to present with typical symptoms and signs. Computed tomography was the most common initial imaging modality, used in 76.3% of patients with an AAD. The overall in-hospital mortality rate was 17.7%, with most of the deaths occurring within the first week. Surgery was used in 75.3% of patients with type A AAD. The mortality in this cohort was 33.8%. Endovascular treatment was performed in 76.1% of patients with type B AAD. The mortality rate was 2.2%. Multivariate analysis showed that hypertension (odds ratio 2.80, p <0.001), Marfan syndrome (odds ratio 1.76, p = 0.017), anterior chest pain (odds ratio 1.62, p = 0.004), abdominal pain (odds ratio 1.51, p = 0.041), migrating pain (odds ratio 1.56, p = 0.04), and arch vessel involvement (odds ratio 1.70, p <0.001) were predictive factors for increased in-hospital mortality in patients with an AAD. In conclusion, our study has provided insight into the current profiles and outcomes of AAD in China. This knowledge might be useful for clinicians when diagnosing and treating these patients. PMID:22762721

Li, Yang; Yang, Nan; Duan, Weixun; Liu, Siqi; Yu, Shiqiang; Yi, Dinghua

2012-07-03

237

The Effect of Animal Dissections on Student Acquisition of Knowledge of and Attitudes toward the Animals Dissected.  

ERIC Educational Resources Information Center

|A conflict exists over the use of animals in the classroom. One aspect of this use involved the dissection of animals. Animal protection advocates report that dissections constitute abuse of the animals dissected. The advocates state that what is learned by dissection could be more effectively learned by other means. Some science educators state…

McCollum, Terry L.

238

Student injuries in the dissecting room.  

PubMed

Cadaver dissection is the first opportunity for many students to practice handling human tissue and is their first exposure to the occupational hazards involved with this task. Few studies examine dissection room injuries to ascertain the dangers associated with dissecting. We performed a retrospective cohort analysis of dissection room injuries from four student cohorts over an eleven-year period (2001-2011), including second-year medical students, third-year medical students, second-year dental students, and third-year science students. Injury data included activity causing injury, object responsible, and injury site. A total of 163 injuries during 70,039 hours of dissection were recorded, with 66 in third-year medical students, 42 in second-year medical students, 36 in third-year science students, and 16 in second-year dental students. The overall rate was 2.87 injuries per 1,000 dissection hours, with second-year medical students most frequently injured (5.5 injuries per 1,000 hours); third-year medical students were least frequently injured (1.3 injuries per 1,000 hours). A significant difference in injury rates between student groups indicated a higher than expected injury rate to second-year medical students and lower than expected rates to third-year medical students. Injury rates increased for most groups between 2001-2006 and 2007-2011 periods. Most injuries (79%) were from scalpel cuts to the finger or thumb. This study provides injury rates for dissection room injuries to students, indicating differences in injury frequency between cohorts and an increase in injury rate over time. As scalpel cuts were the most likely injury mechanism, targeting scalpel handling with preventative strategies may reduce future injury risk. Anat Sci Educ. © 2013 American Association of Anatomists. PMID:23536433

Cornwall, Jon; Davies, Tilman M; Lees, David

2013-03-27

239

Science Teachers and the Dissection Debate: Perspectives on Animal Dissection and Alternatives  

ERIC Educational Resources Information Center

|This study investigated Ontario science and biology teachers' practices and attitudes toward animal dissection and dissection alternatives. The data was collected through a mixed methods approach involving online surveys (n = 153) and subsequent telephone interviews (n = 9) with secondary school science and biology teachers. The findings indicate…

Oakley, Jan

2012-01-01

240

[Eight cases of extracranial vertebral artery dissection].  

PubMed

We present eight cases of extracranial vertebral artery dissection. One of these had traumatic antecedents at the neck level while undergoing massage treatment. Of the rest, in four cases there was only a history of commonplace traumatism at neck level, consisting of twisting or stretching. Most presented pain at this level both before and during symptoms. Five had symptoms compatible with lateral bulbar infarct, two with cerebral infarct and one at the protuberance level. Angiography showed irregular stenosis of the spine on the affected side in five cases, occlusion in three cases. Nuclear magnetic resonance (NMR) was performed on five, with findings compatible with dissection. Six received anticoagulant treatment and two received platelet antiagregants with good recovery except in one patient who died twelve months later without any indication of the existence of dissection. We also carried out a review of the literature with special emphasis on the etiology of spontaneous cases, on clinical and neuroimaging findings and on treatment. PMID:8714482

Pego, R; Marey, J; López-Facal, M S; Marín-Sánchez, M

1996-02-01

241

Prevention of complications in neck dissection  

PubMed Central

Background The neck dissection has remained a pivotal aspect of head and neck cancer management for over a century. During this time its role has expanded from a purely therapeutic option into an elective setting, in part promoted by efforts to reduce its morbidity. Objectives This review will consider the potential complications of neck dissection and on the basis of the available evidence describe both their management and prevention. Conclusion Although the neck dissection continues to provide clinicians with a method of addressing cervical disease, its reliability and safety can only be assured if surgeons remain cognisant of the potential complications and aim to minimise such morbidity by appropriate management in the peri-operative period.

Kerawala, Cyrus J; Heliotos, Manolis

2009-01-01

242

Carotid and vertebral artery dissection syndromes  

PubMed Central

Cervicocerebral arterial dissections (CAD) are an important cause of strokes in younger patients accounting for nearly 20% of strokes in patients under the age of 45 years. Extracranial internal carotid artery dissections comprise 70%–80% and extracranial vertebral dissections account for about 15% of all CAD. Aetiopathogenesis of CAD is incompletely understood, though trauma, respiratory infections, and underlying arteriopathy are considered important. A typical picture of local pain, headache, and ipsilateral Horner's syndrome followed after several hours by cerebral or retinal ischaemia is rare. Doppler ultrasound, MRI/MRA, and CT angiography are useful non-invasive diagnostic tests. The treatment of extracranial CAD is mainly medical using anticoagulants or antiplatelet agents although controlled studies to show their effectiveness are lacking. The prognosis of extracranial CAD is generally much better than that of the intracranial CAD. Recurrences are rare in CAD.

Thanvi, B; Munshi, S; Dawson, S; Robinson, T

2005-01-01

243

Identification of in vivo phosphorylation sites of lens proteins from porcine eye lenses by a gel-free phosphoproteomics approach  

PubMed Central

Purpose Phosphorylation is an important post-translational modification for the cellular regulation of various biosignaling pathways. We have identified in vivo phosphorylation sites of various lens proteins including especially the major structural proteins of the crystallin family from porcine eye lenses by means of two-dimensional gel electrophoresis (2-DE) or immobilized metal affinity chromatography (IMAC) followed by liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS). Methods For the identification of phosphorylated residues in various lens proteins of porcine lens extracts, we have adapted two complementary proteomic approaches, i.e., pre-fractionation of protein samples with 2-DE or enrichment of phosphopeptides with IMAC followed by LC-MS/MS analysis and database search. The results were compared and validated with those in phosphoproteomics databases. Results Two subunits of ?-crystallin, ?A-crystallin and ?B-crystallin, as well as other lens crystallins and non-crystallin cellular proteins, such as ?-enolase, heat shock protein ?-1 (HSP27), and glucose-6-phosphate isomerase (GPI) were found to be phosphorylated in vivo at specific sites. Moreover, ?A- and ?B-crystallins were found to be the most abundantly phosphorylated proteins in porcine lenses, being extensively phosphorylated on serine or threonine, but not on tyrosine residues. Conclusions The complementary gel-based and gel-free proteomic strategies have been compared and evaluated for the study of crystallin phosphorylation from whole tissue extracts of porcine eye lenses. Technically, the IMAC method facilitates direct site-specific identification of phosphorylation residues in lens proteins, which does not necessitate the pre-MS/MS 2-DE separation of protein samples. Moreover, the improved strategy using gel-free phosphoproteomics analysis affords a more effective and simplistic method for the determination of in vivo phosphorylation sites than the conventional 2-DE pre-separation of protein mixture. This study should form a firm basis for the comprehensive analysis of post-translational modification of lens proteins in terms of aging or various diseased states.

Huang, Chun-Hao; Lee, I-Liang; Wang, Yi-Ting; Liu, Nai-Yu; Tsay, Yeou-Guang; Chen, Yu-Ju

2010-01-01

244

The nature of dissection: Exploring student conceptions  

NASA Astrophysics Data System (ADS)

The model of conceptual change in science describes the process of learning as a complete restructuring of knowledge, when learners discover or are shown more plausible, intelligent alternatives to existing conceptions. Emotions have been acknowledged as part of a learner's conceptual ecology, but the effects of emotions on learning have yet to be described. This research was conducted to examine the role that emotions have on learning for thirteen high school students, as they dissected cats in a Human Anatomy and Physiology class. The project also investigated whether a student's emotional reactions may be used to develop a sense of connectedness with the nonhuman world, which is defined as ecological literacy. This study utilized a grounded theory approach, in which student responses to interviews were the primary source of data. Interviews were transcribed, and responses were coded according to a constant comparative method of analysis. Responses were compared with the four conditions necessary for conceptual change to occur, and also to five principles of ecological literacy. Students who had negative reactions to dissection participated less in the activity, and demonstrated less conceptual change. Two female students showed the strongest emotional reactions to dissection, and also the lowest amount of conceptual change. One male student also had strong negative reactions to death, and showed no conceptual change. The dissection experiences of the students in this study did not generally reflect ecological principles. The two students whose emotional reactions to dissection were the most negative demonstrated the highest degree of ecological literacy. These results provide empirical evidence of the effects that emotions have on learning, and also supports the opinions of educators who do not favor dissection, because it does not teach students to respect all forms of life.

York, Katharine

245

Aortic dissection: a 250-year perspective.  

PubMed

Two hundred fifty years have passed since Frank Nicholls' history-making, accurate observations on the anatomic findings and cause of death of King George II were published. Several decades later, the disease was named, using--for the first time--the terms dissection and dissecting attached to an aortic disease process. Another century went by before effective surgical treatment was developed. In sharp contrast, the evolution of the last 20 years has been nothing short of amazing. Our understanding of AD, while not yet complete, has improved dramatically. In addition, the introduction of nonsurgical endovascular therapy has had a profoundly transformative impact--and we are just at the beginning! It would not be unreasonable to predict that stent-graft repair will likely replace (or nearly replace) open surgery in the treatment of complicated type B dissection in the near future, especially as technologies continue to improve and indication-specific designs are developed and tested in the clinical setting. Moreover, it is predictable that endovascular solutions for some patients with type A aortic dissection will become available in the years to come as surgical results continue to be suboptimal. Finally, and amidst this plethora of “good news,” it is appropriate to reflect on the formidable challenge that endovascular therapies face as they gear to “compete” with optimal medical therapy in the management of patients with acute uncomplicated type B dissection, because it will obviously be difficult (if not impossible) to improve on the already-achieved 30-day mortality rate of less than 10%. Long-term gains may well become the winning card when and if the late results of TEVAR can be shown to improve on the rather compromised outlook of medically treated dissection patients. Stay tuned. PMID:22199439

Criado, Frank J

2011-01-01

246

Dissecting apple tree architecture into genetic, ontogenetic and environmental effects: QTL mapping  

Microsoft Academic Search

The present study aimed to dissect tree architectural plasticity into genetic, ontogenetic and environmental effects over\\u000a the first 4 years of growth of an apple F1 progeny by means of quantitative traits loci (QTL) mapping. Both growth and branching\\u000a processes were phenotyped on the consecutive annual shoots of different axes within a tree. For each studied trait, predicted\\u000a values (best linear

Vincent Segura; Charles-Eric Durel; Evelyne Costes

2009-01-01

247

[Surgery of aortic dissection: for which patient?].  

PubMed

In the acute stage (less than two weeks), surgery is indicated for Stanford type A aortic dissections. With respect to the initial work-up, surgery consists in replacing the ascending aorta, sometimes the aortic arch (with supra aortic vessels reimplantation), and aortic valve replacement (valve replacement, Bentall valved tube or valve sparing Tyron David technique). Ischemic visceral complications must be searched for and treated by endovascular techniques or surgery. Aneurismal evolution of chronic dissections must be treated surgically. Replacement can encompass the entire aorta. PMID:21146353

Verhoye, Jean-Philippe; Abouliatim, Issam; Larralde, Antoine; Beneux, Xavier; Heautot, Jean-François

2010-12-10

248

Pregnancy-associated spontaneous coronary artery dissection.  

PubMed

Spontaneous coronary artery dissection is a rare cause of acute myocardial infarction that occurs particularly in women during the pregnancy and in the postpartum period. We describe a dramatic case of pregnancy-related spontaneous left main coronary artery dissection that resulted in acute myocardial infarction with severe left ventricular dysfunction and was complicated by acute heart failure and cardiogenic shock. Urgent revascularization and restoration of myocardial perfusion that were performed in this case resulted in marked left ventricular function recovery and clinical improvement. PMID:18060935

Goland, Sorel; Schwarz, Ernst R; Siegel, Robert J; Czer, Lawrence S C

2007-12-01

249

Spontaneous left main coronary artery dissection.  

PubMed

Spontaneous coronary artery dissection is a rare and generally fatal disease. A review of the literature demonstrates that the aetiopathogenesis of the disease is unknown and that the histology is rarely described. It usually occurs in young women during the post-partum period or while taking oral contraceptives. The treatment depends on the clinical presentation and the results of the angiography. We report here a case of spontaneous dissection of the left main stem coronary artery, with extension into the left coronary territory which which occurred in a 43-year-old woman. PMID:18614552

Cini, Roberto; Iezzi, Federica; Sordini, Paolo; Pasceri, Vincenzo

2008-07-09

250

Acute Type II Aortic Dissection with Severe Aortic Regurgitation and Chronic Descending Aortic Dissection in Pregnant Patient with Marfan Syndrome  

PubMed Central

Aortic dilatation and dissection are severe complications during pregnancy that can be fatal to both the mother and the fetus. The risks of these complications are especially high in pregnant patients with Marfan syndrome; however, incidents of descending aortic dissection are very rare. This case report involves a successful Bentall procedure for and recovery from a rare aortic dissection in a pregnant Marfan patient who developed acute type II aortic dissection with severe aortic regurgitation and chronic descending aortic dissection immediately after Cesarean section. Regular follow-up will be needed to monitor the descending aortic dissection.

Lee, Seok-Soo; Jung, Tae-Eun

2012-01-01

251

Changes in the proteome and phosphoproteome expression in the bryozoan Bugula neritina larvae in response to the antifouling agent butenolide.  

PubMed

Larval attachment and metamorphosis, commonly referred to as larval settlement, of marine sessile invertebrates can be triggered or blocked by chemical cues and affected by changes in overall protein expression pattern and phosphorylation dynamics. This study focuses on the effects of butenolide, an effective larval settlement inhibitor, on larval settlement at the proteome level in the bryozoan Bugula neritina. Liquid-phase IEF sample prefractionation combined with 2-DE and MALDI-TOF MS was used to identify the differentially expressed proteins. Substantial changes occurred both in protein abundance and in phosphorylation status during larval settlement and when settling larvae were challenged with butenolide. The proteins that responded to treatment were identified as structural proteins, molecular chaperones, mitochondrial peptidases and calcium-binding proteins. Compared with our earlier results, both genistein and butenolide inhibited larval settlement of B. neritina primarily by changes in protein abundance and the phosphorylation status of proteins but have different protein targets in the same species. Clearly, to design potent antifouling compounds and to understand the mode of action of compounds, more studies on the effects of different compounds on proteome and phosphoproteome of different larval species are required. PMID:20827734

Qian, Pei-Yuan; Wong, Yue Him; Zhang, Yu

2010-10-01

252

Close proximity of phosphorylation sites to ligand in the phosphoproteome of the extreme thermophile Thermus thermophilus HB8.  

PubMed

We performed phosphoproteome analysis of proteins from the extremely thermophilic Gram-negative eubacterium Thermus thermophilus HB8 using gel-free mass spectrometric method. We identified 52 phosphopeptides from 48 proteins and determined 46 phosphorylation sites: 30 on serine, 12 on threonine, and 4 on tyrosine. The identified phosphoproteins are known to be involved in a wide variety of cellular processes. To help elucidate the functional roles of these phosphorylation events, we mapped the phosphorylation sites on the known tertiary structures of the respective proteins. In all, we succeeded in mapping 46 sites (approximately 88%) on the corresponding structures. Most of the phosphorylation sites were found to be located on loops and terminal regions of the secondary structures. Surprisingly, 28 of these sites were situated at or near the active site of the enzyme. In particular, 18 sites were within 4 Å of the ligand, including substrate or cofactor. Such structural locations suggest direct effects of the phosphorylation on the binding of ligand in addition to inducing a conformational change. Interestingly, 19 of these 28 phosphorylation sites were situated near the phosphate moiety of a substrate or cofactor. In oligomeric proteins, 5 phosphorylation sites were found at the subunit interface. Based on these results, we propose a regulatory mechanism that involves Ser/Thr/Tyr phosphorylation in T. thermophilus HB8. PMID:22589190

Takahata, Yoshio; Inoue, Masao; Kim, Kwang; Iio, Yota; Miyamoto, Masaaki; Masui, Ryoji; Ishihama, Yasushi; Kuramitsu, Seiki

2012-05-01

253

Intraoperative aortic dissection in pediatric heart surgery.  

PubMed

Intraoperative aortic dissection occurred in a 3-year-old-boy undergoing repair of an atrial septal defect. Transesophageal echocardiography was useful for the diagnosis, and conservative medical treatment under close observation was feasible in this case which involved a limited intimal tear. PMID:16714685

Hibino, Narutoshi; Harada, Yorikazu; Hiramatsu, Takeshi; Yasukochi, Satoshi; Satomi, Gengi

2006-06-01

254

Acute aortic dissection: be aware of misdiagnosis  

Microsoft Academic Search

BACKGROUND: Acute aortic dissection (AAD) is a life-threatening condition requiring immediate assessment and therapy. A patient suffering from AAD often presents with an insignificant or irrelevant medical history, giving rise to possible misdiagnosis. The aim of this retrospective study is to address the problem of misdiagnosing AD and the different imaging studies used. METHODS: From January 2000 to December 2004,

Irene Asouhidou; Theodora Asteri

2009-01-01

255

Ultrasound assessment of cervical artery dissection.  

PubMed

The purpose of this chapter is to present ultrasound and, in particular, color duplex sonography (CDS) assessment of spontaneous dissection of the cervical internal carotid (sICAD) and vertebral (sVAD) arteries. The examination, typical ultrasound findings and pitfalls in the acute sICAD and sVAD, detection of microembolic signals, and recanalization will be discussed. PMID:17290115

Benninger, D H; Caso, V; Baumgartner, R W

2005-01-01

256

[Arteriovenous dissection for branch retinal vein occlusion].  

PubMed

Arteriovenous dissection (AVD) is a surgical maneuver to separate the retinal artery and vein at the crossing site in patients with branch retinal vein occlusion (BRVO). The published studies showed an evidence level 3. AVD seems to be maintainable in patients with recent onset of BRVO and decimal visual acuity < or =0.4. PMID:18317778

Feltgen, N; Hattenbach, L-O; Mirshahi, A; Hansen, L

2008-04-01

257

Cow's Eye Dissection in the Physics Lab.  

ERIC Educational Resources Information Center

|Proposes the science demonstration of dissecting a cow's eye to integrate biology and physics in the study of optics and lenses. Reviews the anatomy of the eye, describes the visual process and covers topics as index of refraction of the cornea, microscopic receptors, the lens, and the retina. (MDH)|

Lapp, David R.; Keenan, James E.

1991-01-01

258

Dissecting spider embryos for light microscopy.  

PubMed

INTRODUCTIONThe spider Cupiennius salei, commonly known as the American wandering spider, is a particularly useful laboratory model for embryological studies because of the availability of tools to study and manipulate its embryonic development. Cupiennius is used to study axis formation, segmentation, appendage development, neurogenesis, and silk production. These studies contribute to our understanding of the evolution of these processes, but they also help us to understand the origin and diversification of evolutionary novelties. Comparisons between spiders and insects can show the degree of conservation and divergence of developmental mechanisms during arthropod evolution. Any embryological feature conserved between spiders and insects is likely to represent an ancestral feature for arthropods. Comparative molecular embryological work in insects and spiders should eventually allow us to define a molecular archetype for the phylum Arthropoda. This in itself will be a necessary cornerstone for comparing the different metazoan phyla, including chordates. Spider embryos can be studied as whole mounts under the dissection microscope. Alternatively, the embryos can be dissected and observed under the compound microscope. Preparing and dissecting spider embryos for compound microscopy is difficult due to the high amount of yolk, which makes the embryos very fragile. The following protocol describes how to make the necessary tools, then use them to obtain good preparations. Not all embryonic stages can be dissected and prepared; very young stages can only be examined as whole mounts. PMID:21356703

Prpic, Nikola-Michael; Schoppmeier, Michael; Damen, Wim G M

2008-10-01

259

Toward the development of interactive virtual dissection with haptic feedback  

Microsoft Academic Search

Traditional, hands-on dissection of an animal is common practice in many classrooms to aid in the study of anatomy and biology.\\u000a More specifically, virtual dissection environments have been developed making it possible to study the inner workings of animals\\u000a without cutting them up. In this paper, we present a novel virtual reality dissection simulator, where a user can dissect\\u000a an

Nasim Melony Vafai; Shahram Payandeh

2010-01-01

260

Spontaneous bilateral carotid artery dissection following cervical manipulation.  

PubMed

We report an autopsy case of a bilateral carotid artery dissection, following cervical manipulation by a chiropractor. To establish the etiology of a cervical artery dissection is important in view of possible legal implications and to exclude hereditary disorders, since cervical artery dissection has been linked to several arteriopathies. The underlying arteriopathy in the presented case was an idiopathic cystic medial degeneration. This report emphasizes the role of the pathologist in defining the underlying arteriopathy in carotid artery dissection. PMID:22633562

Carprieaux, Marilyn; Michotte, Alex; Van Varenbergh, Dirk; Marichal, Miriam Pipeleers

2012-05-23

261

Pediatric tonsillectomy: post-operative morbidity comparing microsurgical bipolar dissection versus cold sharp dissection  

Microsoft Academic Search

A prospective single-blinded study was conducted to compare pediatric tonsillectomy using the traditional cold sharp dissection with ligation for securing hemostasis (CSDL) versus microsurgical bipolar dissection technique (MBCT). Sixty children aged between 2 and 14 years were sequentially assigned to each group. Blood loss and postoperative pain in the first hour were markedly decreased in the MBCT group (P<0.0001 and

Luis Lassaletta; Gonzalo Mart??n; Miguel Angel Villafruela; Caridad Bolaños; Juan José Álvarez-Vicent

1997-01-01

262

Total arch replacement with elephant trunk procedure for retrograde dissection  

Microsoft Academic Search

BackgroundThe surgical management of type A dissection with the intimal tear in the descending aorta—retrograde dissection—has some challenging aspects because the standard approach through a median sternotomy for ascending aortic dissection is difficult in these cases in which the intimal tear is located in the descending aorta.

Yuji Hanafusa; Hitoshi Ogino; Hiroaki Sasaki; Kenji Minatoya; Motomi Ando; Yutaka Okita; Soichiro Kitamura

2002-01-01

263

Duplex Scan Findings in Patients with Spontaneous Cervical Artery Dissections  

Microsoft Academic Search

Aim to report duplex scan findings in patients with spontaneous internal carotid artery (ICA) or vertebral artery (VA) dissection. Material and methods the records of 24 patients (13 males and 11 females, median age 48 years [range 25–68 years]) with spontaneous extracranial ICA dissection (n=20) or VA dissection (n=4), identified between January 1995 and December 1999, were retrospectively analysed. Results

K. Logason; H.-G. Hårdemark; T. Bärlin; D. Bergqvist; H. Ahlstöm; S. Karacagil

2002-01-01

264

Spontaneous carotid and vertebral artery dissection in children  

Microsoft Academic Search

Carotid and vertebral artery dissection is a rarely reported cause of stroke in childhood and adolescence, especially if there is not a direct trauma to the neck. Four patients, under 15 years of age, presented with an internal carotid artery dissection, and one patient presented with a vertebral artery dissection. They were all making a physical effort when the event

Ana Camacho; Alberto Villarejo; Ana Mart??nez de Aragón; Rogelio Simón; Fernando Mateos

2001-01-01

265

Which Comes First: The Use of Computer Simulation of Frog Dissection or Conventional Dissection as Academic Exercise?  

ERIC Educational Resources Information Center

|Science educators and school administrators are reexamining the educational value of animal dissection in the nation's schools and are focusing on simulation as an instructional alternative. One implication of the debate is that simulations can lead to equivalent learning to hands-on dissection. The second implication is whether dissection is…

Akpan, Joseph; Strayer, Jeremy

2010-01-01

266

A comparison of retention of anatomical knowledge in an introductory college biology course: Traditional dissection vs. virtual dissection  

Microsoft Academic Search

Dissection has always played a crucial role in biology and anatomy courses at all levels of education. However, in recent years, ethical concerns, as well as improved technology, have brought to the forefront the issue of whether virtual dissection is as effective or whether it is more effective than traditional dissection. Most prior research indicated the two methods produced equal

Kelli Rae Taeger

2006-01-01

267

Endovascular approaches and perioperative considerations in acute aortic dissection.  

PubMed

Aortic dissections remain complicated management issues both in the acute setting and in the chronic setting. Acute problems revolve around malperfusion syndromes or rupture, whereas chronic issues progress from the development of aneurysms in the residual dissected aorta. Endovascular approaches to dealing with these difficult situations are being used more frequently to treat acute issues in type B dissections and prevent secondary complications in type A dissections that may require significant intervention in the future. This article discusses the endovascular approaches employed in the care of acute dissections with particular attention toward the anesthetic considerations involved in these challenging cases. PMID:22194281

Jazaeri, Omid; Gupta, Rajan; Rochon, Paul J; Reece, T Brett

2011-12-22

268

Spontaneous dissection of the celiac artery: a case report.  

PubMed

Spontaneous dissection of visceral arteries is rare in the absence of concurrent dissection of the aorta, iatrogenic injury from instrumentation, or trauma. We describe a spontaneous dissection of the celiac artery that was identified by computed tomographic scan in an otherwise healthy man with acute onset abdominal pain and no identifiable causes of dissection. The patient was successfully managed medically. Although endovascular treatment or surgical intervention is the procedure of choice for complicated cases, medical management with close observation is an acceptable management strategy for stable, uncomplicated cases of spontaneous celiac artery dissection. PMID:17543692

Woolard, Jason D; Ammar, Alex D

2007-06-01

269

Modified functional neck dissection: a useful technique for oral cancers.  

PubMed

Among 60 patients with oral squamous cell carcinoma, 30 were treated by the modified functional neck dissection (preserve 8 functional tissues), 30 were treated by functional neck dissection (preserve 3 functional tissues). The recurrent rate of cervical lymph node and the sense of skin were assessed. The recurrence rates in cervical nodes was 6.67% and 10%, respectively (p > 0.05) in patients who accepted modified functional neck dissection and functional neck dissection. The sensation in skin in patients who accepted modified functional neck dissection was better than those who accepted functional neck dissection (p < 0.01). Modified functional neck dissection is helpful to decrease postoperative complications, without increasing recurrent rates of cervical lymph node. PMID:16139562

Minghua, Ge; Zhiyuan, Gu; Zhun, Jin; Han, Chun

2005-08-31

270

Management of Posterior Fossa Dissecting Aneurysms  

PubMed Central

Summary Treatment and prognosis of 14 patients of posterior fossa arterial dissections (AD) and dissecting aneurysms (DA) in one institution was reviewed. Internal trapping of aneurysm was performed for six patients presenting with SAH (three Vertebral, one posterior cerebral, one posterior inferior cerebellar, one anterior inferior cerebellar DA). The patency of the parent arteries was preserved in four DA patients with SAH (two Vertebral, two Basilar DA), 1 incidental vertebral DA, and one DA patient with brainstem infarction using stents and coils (four patients) or coils only (two patient). Proximal occlusion of parent artery was performed in a vertebral DA with SAH. One patient with a superior cerebellar DA presented with a midbrain infarct developed SAH with spontaneous occlusion of the aneurysm two weeks later. Of the 14 cases, ten were angiographically stable or cured during a follow up period of four to 70 months. one spontaneously resolved and two recurred. There was one death.

Winston Chong, W. K.

2008-01-01

271

Laparoscopic Retroperitoneal Lymph Node Dissection: Extraperitoneal Approach  

Microsoft Academic Search

We review our early experience with laparoscopic retroperitoneal lymph node dissection (RPLND) via extraperitoneal approach\\u000a to assess the precise pathological status of retroperitoneal lymph nodes in early-stage testicular cancer. A total of 32 patients\\u000a (23 with stage I, 4 with stage IIa, and 5 with stage IIb) with testicular cancer underwent extraperitoneal laparoscopic RPLND\\u000a in the supine position. After developing

Makoto Satoh; Akihiro Ito; Yoichi Arai

272

Endovascular Stent in Traumatic Thoracic Aortic Dissection  

PubMed Central

Traumatic thoracic aortic injury is typically fatal. However, recent improvements in pre-hospital care and diagnostic modalities have resulted in an increased number of patients with traumatic aortic injury arriving alive at the hospital. Also, the morbidity and mortality associated with endovascular repair are significantly lower than with conventional open surgery in traumatic thoracic aorta injury. We experienced two cases of successful management of traumatic thoracic aortic dissection with endovascular stents caused by traffic accidents.

Jang, Mi Ok; Kim, Ju Han; Oh, Sang Ki; Lee, Min Goo; Park, Keun Ho; Sim, Doo Sun; Hong, Young Joon; Ahn, Youngkeun

2012-01-01

273

The Phosphoproteome of a Chlamydomonas reinhardtii Eyespot Fraction Includes Key Proteins of the Light Signaling Pathway1[W  

PubMed Central

Flagellate green algae have developed a visual system, the eyespot apparatus, which allows the cell to phototax. In a recent proteomic approach, we identified 202 proteins from a fraction enriched in eyespot apparatuses of Chlamydomonas reinhardtii. Among these proteins, five protein kinases and two protein phosphatases were present, indicating that reversible protein phosphorylation occurs in the eyespot. About 20 major phosphoprotein bands were detected in immunoblots of eyespot proteins with an anti-phosphothreonine antibody. Toward the profiling of the targets of protein kinases in the eyespot fraction, we analyzed its phosphoproteome. The solubilized proteins of the eyespot fraction were treated with the endopeptidases LysC and trypsin prior to enrichment of phosphopeptides with immobilized metal-ion affinity chromatography. Phosphopeptides were analyzed by nano-liquid chromatography-electrospray ionization-mass spectrometry (MS) with MS/MS as well as neutral-loss-triggered MS/MS/MS spectra. We were able to identify 68 different phosphopeptides along with 52 precise in vivo phosphorylation sites corresponding to 32 known proteins of the eyespot fraction. Among the identified phosphoproteins are enzymes of carotenoid and fatty acid metabolism, putative signaling components, such as a SOUL heme-binding protein, a Ca2+-binding protein, and an unusual protein kinase, but also several proteins with unknown function. Notably, two unique photoreceptors, channelrhodopsin-1 and channelrhodopsin-2, contain three and one phosphorylation sites, respectively. Phosphorylation of both photoreceptors occurs in the cytoplasmatic loop next to their seven transmembrane regions in a similar distance to that observed in vertebrate rhodopsins, implying functional importance for regulation of these directly light-gated ion channels relevant for the photoresponses of C. reinhardtii.

Wagner, Volker; Ullmann, Katharina; Mollwo, Anne; Kaminski, Marc; Mittag, Maria; Kreimer, Georg

2008-01-01

274

Integrated phosphoproteomic and metabolomic profiling reveals NPM-ALK-mediated phosphorylation of PKM2 and metabolic reprogramming in anaplastic large cell lymphoma.  

PubMed

The mechanisms underlying the pathogenesis of the constitutively active tyrosine kinase nucleophosmin-anaplastic lymphoma kinase (NPM-ALK) expressing anaplastic large cell lymphoma are not completely understood. Here we show using an integrated phosphoproteomic and metabolomic strategy that NPM-ALK induces a metabolic shift toward aerobic glycolysis, increased lactate production, and biomass production. The metabolic shift is mediated through the anaplastic lymphoma kinase (ALK) phosphorylation of the tumor-specific isoform of pyruvate kinase (PKM2) at Y105, resulting in decreased enzymatic activity. Small molecule activation of PKM2 or expression of Y105F PKM2 mutant leads to reversal of the metabolic switch with increased oxidative phosphorylation and reduced lactate production coincident with increased cell death, decreased colony formation, and reduced tumor growth in an in vivo xenograft model. This study provides comprehensive profiling of the phosphoproteomic and metabolomic consequences of NPM-ALK expression and reveals a novel role of ALK in the regulation of multiple components of cellular metabolism. Our studies show that PKM2 is a novel substrate of ALK and plays a critical role in mediating the metabolic shift toward biomass production and tumorigenesis. PMID:23814019

McDonnell, Scott R P; Hwang, Steven R; Rolland, Delphine; Murga-Zamalloa, Carlos; Basrur, Venkatesha; Conlon, Kevin P; Fermin, Damian; Wolfe, Thomas; Raskind, Alexander; Ruan, Chunhai; Jiang, Jian-Kang; Thomas, Craig J; Hogaboam, Cory M; Burant, Charles F; Elenitoba-Johnson, Kojo S J; Lim, Megan S

2013-06-27

275

Aortic dissection: anatomic types and surgical approaches.  

PubMed

Our classification system of acute dissection of the aorta is based on the site of the main intimal tear: Type A: on the ascending aorta; type B: on the transverse aortic arch; type C: on the descending aorta. The extension of the dissecting process is classified as "antegrade" or "retrograde". Acute dissection involving the ascending aorta is an absolute surgical urgency. Any delay in referring the patient to a proper surgical institution or to the operating room increases the risk of death. Fifty per cent of patients, indeed, either untreated or medically supported, die within 48 hours after the onset of symptoms. Surgical therapy is mainly aimed at preventing the patient from dying from intrapericardial rupture of the aorta or from acute massive aortic regurgitation. In type A, it is necessary to replace the ascending aorta with a bloodtight Dacron prosthesis after resecting the entry site, if possible. Downstream, joining the two dissected cylinders by two running sutures and the aid of GRF glue, seals the false lumen. Upstream, the reconstruction of the aortic root and the resuspension of the aortic valve, also by means of running sutures and GRF glue, suppress the aortic valve insufficiency in 90% patients. However, in case of pre-existing annulo-aortic ectasia, the ascending aorta must be replaced by a composite tube according to the Bentail technique. The use of GRF glue since the beginning of 1977, has dramatically improved the immediate and long-term results, accounting for a hospital mortality rate of 10%, in patients less than 65 years old. In type B, resecting the entry site requires that the transverse arch be partially or totally replaced. It is, therefore, mandatory to protect the Central Nervous System. In our experience this is best achieved by perfusing the carotid arteries with cold blood (6 degrees C) during circulatory arrest at moderate core hypothermia (28 degrees C). With this technique of "Cerebroplegia", the hospital mortality rate has been lowered to 28%, higher, though, than in patients undergoing isolated replacement of the ascending aorta. In type C, only the dissections demonstrating symptoms of major complications (rupture or deleterious ischemia) require urgent surgical treatment. In the remaining cases, medical treatment, based on permanent and accurate control of the patient's blood pressure, lead to a good long-term survival rate. Close survey at regular intervals, by means of CT scan or MNR is mandatory to detect any aneurysmal evolution, which may require surgery.(ABSTRACT TRUNCATED AT 400 WORDS) PMID:8482700

Guilmet, D; Bachet, J; Goudot, B; Dreyfus, G; Martinelli, G L

1993-02-01

276

Gene expression in acute Stanford type A dissection: a comparative microarray study  

PubMed Central

Background We compared gene expression profiles in acutely dissected aorta with those in normal control aorta. Materials and methods Ascending aorta specimen from patients with an acute Stanford A-dissection were taken during surgery and compared with those from normal ascending aorta from multiorgan donors using the BD Atlas™ Human1.2 Array I, BD Atlas™ Human Cardiovascular Array and the Affymetrix HG-U133A GeneChip®. For analysis only genes with strong signals of more than 70 percent of the mean signal of all spots on the array were accepted as being expressed. Quantitative real-time polymerase chain reaction (RT-PCR) was used to confirm regulation of expression of a subset of 24 genes known to be involved in aortic structure and function. Results According to our definition expression profiling of aorta tissue specimens revealed an expression of 19.1% to 23.5% of the genes listed on the arrays. Of those 15.7% to 28.9% were differently expressed in dissected and control aorta specimens. Several genes that encode for extracellular matrix components such as collagen IV ?2 and -?5, collagen VI ?3, collagen XIV ?1, collagen XVIII ?1 and elastin were down-regulated in aortic dissection, whereas levels of matrix metalloproteinases-11, -14 and -19 were increased. Some genes coding for cell to cell adhesion, cell to matrix signaling (e.g., polycystin1 and -2), cytoskeleton, as well as several myofibrillar genes (e.g., ?-actinin, tropomyosin, gelsolin) were found to be down-regulated. Not surprisingly, some genes associated with chronic inflammation such as interleukin -2, -6 and -8, were up-regulated in dissection. Conclusion Our results demonstrate the complexity of the dissecting process on a molecular level. Genes coding for the integrity and strength of the aortic wall were down-regulated whereas components of inflammatory response were up-regulated. Altered patterns of gene expression indicate a pre-existing structural failure, which is probably a consequence of insufficient remodeling of the aortic wall resulting in further aortic dissection.

Weis-Muller, Barbara Theresia; Modlich, Olga; Drobinskaya, Irina; Unay, Derya; Huber, Rita; Bojar, Hans; Schipke, Jochen D; Feindt, Peter; Gams, Emmeran; Muller, Wolfram; Goecke, Timm; Sandmann, Wilhelm

2006-01-01

277

[A case of vertebral artery dissection with recurrent brain embolism].  

PubMed

We report a 63-year-old case of the vertebral artery dissection with recurrent brain embolisms. She was admitted to the hospital because she suffered a visual symptom. She was examined by magnetic resonance imaging (MRI) and diagnosed a left vertebral artery (VA) dissection. Digital subtraction angiography (DSA) revealed the string sign on the left VA supporting the evidence of dissection. However, after DSA, multiple brain embolic stroke was occurred. She was treated with anti-platelet drug (sodium ozagrel), then, recanalization of the pseudo-lumen at the dissecting lesion was observed by MRI examination. Anti-platelet medicine (cilostazol) was taken for preventing reattack although the dissecting lesion was not closed. Following 4 weeks, brain embolisms were observed in the posterior circulation system. MRI revealed a dilated pseudo-lumen at the dissecting lesion with recurrent VA. This time, she was treated only with free radical scavenger (edarabone). After the occlusion of the dissected VA was observed, she started to take anti-platelet medicine again. It is generally accepted to use anti-platelet drug or anti-coagulant drug as a treatment of VA dissection causing brain ischemia. However, it should be assessed more carefully in cases showing recanalization of the pseudo-lumen as observed in this case. Surgical treatments should be taken into consideration at the early stage, especially for the cases presenting fragile dissecting lesions. Further study need to decide the effective treatment of the vertebral artery dissection. PMID:16629450

Nakase, Taizen; Suzuki, Akifumi; Okane, Kumiko; Nagata, Ken

2006-03-01

278

Quantitative analysis  

PubMed Central

Quantitative analysis permits the isolation of invariant relations in the study of behavior. The parameters of these relations can serve as higher-order dependent variables in more extensive analyses. These points are illustrated by reference to quantitative descriptions of performance maintained by concurrent schedules, multiple schedules, and signal-detection procedures. Such quantitative descriptions of empirical data may be derived from mathematical theories, which in turn can lead to novel empirical analyses so long as their terms refer to behavioral and environmental events. Thus, quantitative analysis is an integral aspect of the experimental analysis of behavior.

Nevin, John A.

1984-01-01

279

Proteomic and phosphoproteomic comparison of human ES and iPS cells  

PubMed Central

Combining high mass accuracy mass spectrometry, isobaric tagging, and novel software for multiplexed, large-scale protein quantification, we report deep proteomic coverage across multiple biological replicates and cell lines. We applied this method to study four human embryonic stem cell and four induced pluripotent stem cell lines in biological triplicate, a 24-sample comparison resulting in the largest set of identified proteins and phosphorylation sites in pluripotent cells to date. The statistical analysis afforded by this approach revealed, for the first time, subtle but reproducible differences in protein and protein phosphorylation between embryonic stem cells and induced pluripotent cells. Merging these results with RNA-seq analyses, we found functionally related differences across each tier of regulation. Finally, we introduce the Stem Cell–Omics Repository (SCOR), a resource that collates and displays quantitative information across multiple planes of measurement, including mRNA, protein, and post-translational modifications.

Phanstiel, Douglas H.; Brumbaugh, Justin; Wenger, Craig D.; Tian, Shulan; Probasco, Mitchell D.; Bailey, Derek J.; Swaney, Danielle L.; Tervo, Mark A.; Bolin, Jennifer M.; Ruotti, Victor; Stewart, Ron; Thomson, James A.; Coon, Joshua J.

2012-01-01

280

Molecular dissection of developmental behavior of plant height in rice (Oryza sativa L.).  

PubMed

A doubled haploid population of 123 lines from IR64/Azucena was used to dissect the developmental behavior and genotype by environment interaction for plant height by conditional and unconditional quantitative trait loci (QTL) mapping methods in rice. It was shown that the number of QTL detected was different at various measuring stages. Some QTL could be detected at all stages and some only at one or several stages. More QTL could be found on the basis of time-dependent measures of different stages. By conditional QTL mapping of time-dependent measures, it is possible to reveal dynamic gene expression for quantitative traits. Mapping QTL for genetic main effects and GE interaction effects could help us in understanding the nature of QTL x environment interaction for the development of quantitative traits. PMID:9799277

Yan, J; Zhu, J; He, C; Benmoussa, M; Wu, P

1998-11-01

281

Quantitative fractography  

Microsoft Academic Search

In many disciplines, such as biology, botany, geology, materials science and medicine, quantitative image analysis is being used to an increasing extent. In materials science this technique makes it possible to relate the microsctructure to the mechanical properties. In this review we shall show that image analysis can be applied in a fractographic study to characterize quantitatively the morphology of

J. L. Chermant; M. Coster

1979-01-01

282

Metabolic Signature of Electrosurgical Liver Dissection  

PubMed Central

Background and Aims High frequency electrosurgery has a key role in the broadening application of liver surgery. Its molecular signature, i.e. the metabolites evolving from electrocauterization which may inhibit hepatic wound healing, have not been systematically studied. Methods Human liver samples were thus obtained during surgery before and after electrosurgical dissection and subjected to a two-stage metabolomic screening experiment (discovery sample: N?=?18, replication sample: N?=?20) using gas chromatography/mass spectrometry. Results In a set of 208 chemically defined metabolites, electrosurgical dissection lead to a distinct metabolic signature resulting in a separation in the first two dimensions of a principal components analysis. Six metabolites including glycolic acid, azelaic acid, 2-n-pentylfuran, dihydroactinidiolide, 2-butenal and n-pentanal were consistently increased after electrosurgery meeting the discovery (p<2.0×10?4) and the replication thresholds (p<3.5×10?3). Azelaic acid, a lipid peroxidation product from the fragmentation of abundant sn-2 linoleoyl residues, was most abundant and increased 8.1-fold after electrosurgical liver dissection (preplication?=?1.6×10?4). The corresponding phospholipid hexadecyl azelaoyl glycerophosphocholine inhibited wound healing and tissue remodelling in scratch- and proliferation assays of hepatic stellate cells and cholangiocytes, and caused apoptosis dose-dependently in vitro, which may explain in part the tissue damage due to electrosurgery. Conclusion Hepatic electrosurgery generates a metabolic signature with characteristic lipid peroxidation products. Among these, azelaic acid shows a dose-dependent toxicity in liver cells and inhibits wound healing. These observations potentially pave the way for pharmacological intervention prior liver surgery to modify the metabolic response and prevent postoperative complications.

von Schonfels, Witigo; von Kampen, Oliver; Patsenker, Eleonora; Stickel, Felix; Schniewind, Bodo; Hinz, Sebastian; Ahrens, Markus; Balschun, Katharina; Egberts, Jan-Hendrik; Richter, Klaus; Landrock, Andreas; Sipos, Bence; Will, Olga; Huebbe, Patrizia; Schreiber, Stefan; Nothnagel, Michael; Rocken, Christoph; Rimbach, Gerald; Becker, Thomas

2013-01-01

283

Vertebral and carotid artery dissection following chiropractic cervical manipulation  

Microsoft Academic Search

A 50-year-old woman presented a sudden left occipital headache and a posterior circulation stroke after cervical manipulation\\u000a for neck pain. Magnetic resonance imaging documented a left intracranial vertebral artery occlusive dissection associated\\u000a with an ipsilateral internal carotid artery dissection with vessel stenosis in its prepetrous tract. This is the first reported\\u000a case showing an associate vertebral and carotid artery dissection

Giuliano Parenti; Giovanni Orlandi; Mariacristina Bianchi; Maria Renna; Antonio Martini; Luigi Murri

1999-01-01

284

Natural history of a giant coronary aneurysm with spontaneous dissection.  

PubMed

Primary spontaneous coronary artery dissection may appear in young women during the peripartum period or as a result of atherosclerosis. We present a patient with familial hypercholesterolemia who developed a giant aneurysm of the right coronary artery in the setting of atherosclerotic spontaneous coronary dissection over an 8 year period. This report illustrates the association between spontaneous coronary artery dissection and subsequent coronary aneurysm formation. PMID:20014206

Bouzas-Mosquera, Alberto; Vázquez-González, Nicolás; Alvarez-García, Nemesio; Soler, Rafaela; Rodríguez, Esther; Calviño-Santos, Ramón; Castro-Beiras, Alfonso

2009-12-01

285

Iatrogenic left main artery dissection: A catastrophic complication  

PubMed Central

Iatrogenic left main artery (LM) dissection is a catastrophic complication of coronary angiography and angioplasty that requires prompt management using stenting. Although LM dissection can be prevented, it cannot always be avoided and has a reported incidence rate of 0.02%. In the present report, a case of iatrogenic LM dissection that was successfully treated with multiple stents is presented and followed by a brief review of the literature.

Namazi, Mohammad Hassan; Rostami, Reza Tajik; Mohammadi, Afsaneh; Amini, Abdol Latifi; Safi, Morteza; Saadat, Habibollah; Vakili, Hosein; Motamedi, Mohammad Reza; Movahed, Mohammad Reza

2012-01-01

286

Hypertrophy of the sternoclavicular joint after functional neck dissection  

Microsoft Academic Search

Sternoclavicular joint hypertrophy is anecdotally reported as a common sequela to radical neck dissection. It is postulated\\u000a that sternoclavicular joint hypertrophy is a result of a combination of spinal accessory nerve division and sternocleidomastoid\\u000a muscle resection during radical neck dissection. However, we noticed that sternoclavicular joint hypertrophy can occur following\\u000a functional neck dissection with preservation of the spinal accessory nerve,

Mohamed A. Ellabban; Greg O’Neill; Stephen Morley; David S. Soutar

2008-01-01

287

Endovascular repair of a double-lumen dissecting aneurysm.  

PubMed

Treating dissections and dissecting aneurysms requires maintenance of flow through the true lumen and exclusion of the false lumen from the circulation. A dissecting aneurysm of the vertebral artery presented with both a true and false lumen within the aneurysmal sac. Stenting of the true lumen followed by coil embolization of both lumens was performed. Management options and decision-making are discussed for this unique situation. PMID:23761478

Johnson, Andrew Kelly; Gerard, Carter S; Lopes, Demetrius Klee

2013-06-12

288

Endovascular repair of a double-lumen dissecting aneurysm.  

PubMed

Treating dissections and dissecting aneurysms requires maintenance of flow through the true lumen and exclusion of the false lumen from the circulation. A dissecting aneurysm of the vertebral artery presented with both a true and false lumen within the aneurysmal sac. Stenting of the true lumen followed by coil embolization of both lumens was performed. Management options and decision-making are discussed for this unique situation. PMID:23737597

Johnson, Andrew Kelly; Gerard, Carter S; Lopes, Demetrius Klee

2013-06-03

289

MRI and MR angiography of vertebral artery dissection  

Microsoft Academic Search

A review of 4,500 angiograms yielded 11 patients with dissection of the vertebral arteries who had MRI and (in 4 patients)\\u000a MR angiography (MRA) in the acute phase of stroke. One patient with incidental discovery at arteriography of asymptomatic\\u000a vertebral artery dissection and two patients with acute strokes with MRI and MRA findings consistent with vertebral artery\\u000a dissection were included.

M. Mascalchi; M. C. Bianchi; S. Mangiafico; G. Ferrito; M. Puglioli; E. Marin; S. Mugnai; R. Canapicchi; N. Quilici; D. Inzitari

1997-01-01

290

Dissecting aortic aneurysm in a horse.  

PubMed

A case of dissecting aortic aneurysm in a 4-year-old male thoroughbred horse is reported. The horse had a history of inflammation in the right thigh and a fever 2 weeks before sudden death. At necropsy, aortic aneurysms were observed from the aortic valve to the aortic arch, spreading over a distance of 40 cm. An irregular rupture of the intima of the ascending aorta was located in the cardiac side of a ramification to the tunica branchiocephalicus communis. An intramural haematoma, apparent on the cut surface and in the pericardium, had caused cardiac tamponade and sudden death. PMID:10213675

Shirai, W; Momotani, E; Sato, T; Kashima, T; Saito, T; Itoi, Y

1999-04-01

291

Intravenous aortography after aortic dissection repair  

SciTech Connect

Eleven patients were studied after aortic dissection repair, using a technique of intravenous angiography with a line-scanned projection radiography prototype. A computed tomographic scanner was modified to produce line-scanned projection images of the aorta, using temporal or dual energy subtraction in combination with intravenous injection of diatrizoate. Excellent visualization of the Dacron graft, persistent intimal flaps, and aneurysmal dilation of the aorta were obtained in nine patients. Patient respiration when temporal subtraction was used and prolonged circulation time contributed to the two inadequate studies.

Guthaner, D.F.; Brody, W.R.; Miller, D.C.

1981-11-01

292

Spontaneous cervical and cerebral arterial dissections: diagnosis and management.  

PubMed

Arterial dissections of head and neck arteries were first identified pathologically in the 1950s, but not until the 1970s and the 1980s did they begin to be widely recognized as a clinical entity. Carotid and vertebral artery dissections account for only 2% of all ischemic strokes, but they account for approximately 20% of thromboembolic strokes in patients younger than 45 years. The cause of supra-aortic dissections can be either spontaneous or traumatic. This article addresses spontaneous cervical and cerebral artery dissections. PMID:24156857

Rahme, Rudy J; Aoun, Salah G; McClendon, Jamal; El Ahmadieh, Tarek Y; Bendok, Bernard R

2013-05-17

293

Subarachnoid Hemorrhage as a Presentation of Basilar Artery Dissection  

Microsoft Academic Search

Introduction  Subarachnoid hemorrhages caused by intracranial dissections are rare. The management of dissections in these cases not clear.\\u000a \\u000a \\u000a \\u000a Methods  Case report.\\u000a \\u000a \\u000a \\u000a Results  An 82-year-old woman presented with acute drowsiness and vomiting. CT scan demonstrated extensive subarachnoid hemorrhage\\u000a and hydrocephalus that subsequently required placement of ventriculoperitoneal shunt. Angiography revealed extensive basilar\\u000a artery dissection and no aneurysms. The dissection did not produce a critical stenosis

Alexander Y. Zubkov; Amit N. Sanghvi; Harry J. Cloft; Eelco F. M. Wijdicks; Alejandro A. Rabinstein

2007-01-01

294

Spontaneous left main coronary artery dissection: a case report.  

PubMed

Coronary artery dissection is a devastating disease, but spontaneous left main coronary artery dissection is extremely rare. We present the case of a 58-year-old diabetic man who was found to have primary spontaneous left main coronary artery dissection during a coronary angiography examination. Although the dissecting lesion persisted, he had no peri-procedural chest discomfort or electrocardiographic change. We performed urgent coronary artery bypass grafting, which was uneventful. The patient received regular cardiovascular follow-up and did not complain of any postoperative chest discomfort. He had an uneventful recovery. PMID:14604324

Lin, Tsung-Hsien; Lee, Kun-Tai; Chiu, Chaw-Cho; Lai, Wen-Ter; Lin, Young-Yso; Sheu, Sheng-Hsiung

2003-09-01

295

Dissecting specific and global transcriptional regulation of bacterial gene expression  

PubMed Central

Gene expression is regulated by specific transcriptional circuits but also by the global expression machinery as a function of growth. Simultaneous specific and global regulation thus constitutes an additional—but often neglected—layer of complexity in gene expression. Here, we develop an experimental-computational approach to dissect specific and global regulation in the bacterium Escherichia coli. By using fluorescent promoter reporters, we show that global regulation is growth rate dependent not only during steady state but also during dynamic changes in growth rate and can be quantified through two promoter-specific parameters. By applying our approach to arginine biosynthesis, we obtain a quantitative understanding of both specific and global regulation that allows accurate prediction of the temporal response to simultaneous perturbations in arginine availability and growth rate. We thereby uncover two principles of joint regulation: (i) specific regulation by repression dominates the transcriptional response during metabolic steady states, largely repressing the biosynthesis genes even when biosynthesis is required and (ii) global regulation sets the maximum promoter activity that is exploited during the transition between steady states.

Gerosa, Luca; Kochanowski, Karl; Heinemann, Matthias; Sauer, Uwe

2013-01-01

296

Analysis of quantitative trait loci that influence animal behavior  

Microsoft Academic Search

Behavioral differences between in- bred strains of mice and rats have a genetic basis that can now be dissected using quantitative trait locus (QTL) analysis. Over the last 10 years, a large number of genetic loci that influence behavior have been mapped. In this article I review what that information has revealed about the genetic architecture of behavior. I show

Jonathan Flint

2003-01-01

297

Thoracic aortic aneurysms and dissections: endovascular treatment.  

PubMed

The treatment of thoracic aortic disease has changed radically with the advances made in endovascular therapy since the concept of thoracic endovascular aortic repair was first described 15 years ago. Currently, there is a diverse array of endografts that are commercially available to treat the thoracic aorta. Multiple studies, including industry-sponsored and single-institution reports, have demonstrated excellent outcomes of thoracic endovascular aortic repair for the treatment of thoracic aortic aneurysms, with less reported perioperative morbidity and mortality in comparison with conventional open repair. Additionally, similar outcomes have been demonstrated for the treatment of type B dissections. However, the technology remains relatively novel, and larger studies with longer term outcomes are necessary to more fully evaluate the role of endovascular therapy for the treatment of thoracic aortic disease. This review examines the currently available thoracic endografts, preoperative planning for thoracic endovascular aortic repair, and outcomes of thoracic endovascular aortic repair for the treatment of both thoracic aortic aneurysms and type B aortic dissections. Mt Sinai J Med 77:256-269, 2010. (c) 2010 Mount Sinai School of Medicine. PMID:20506451

Baril, Donald T; Cho, Jae S; Chaer, Rabih A; Makaroun, Michel S

298

Homarus Americanus Stomatogastric Nervous System Dissection  

PubMed Central

With the goal of understanding how nervous systems produce activity and respond to the environment, neuroscientists turn to model systems that exhibit the activity of interest and are accessible and amenable to experimental methods. The stomatogastric nervous system (STNS) of the American lobster (Homarus americanus; also know was the Atlantic or Maine lobster) has been established as a model system for studying rhythm generating networks and neuromodulation of networks. The STNS consists of 3 anterior ganglia (2 commissural ganglia and an oesophageal ganglion), containing modulatory neurons that project centrally to the stomatogastric ganglion (STG). The STG contains approximately 30 neurons that comprise two central pattern generating networks, the pyloric and gastric networks that underlie feeding behaviors in crustaceans1,2. While it is possible to study this system in vivo3, the STNS continues to produce its rhythmic activity when isolated in vitro. Physical isolation of the STNS in a dish allows for easy access to the somata in the ganglia for intracellular electrophysiological recordings and to the nerves of the STNS for extracellular recordings. Isolating the STNS is a two-part process. The first part, dissecting the stomach from the animal, is described in an accompanying video article4. In this video article, fine dissection techniques are used to isolate the STNS from the stomach. This procedure results in a nervous system preparation that is available for electrophysiological recordings.

Tobin, Anne-Elise; Bierman, Hilary S.

2009-01-01

299

Partial Root Remodeling on the Two Sinuses for Acute Type A Aortic Dissection with Right Coronary Arterial Dissection  

PubMed Central

We reported simple partial root remodeling using a graft trimmed twin “U” shape for extensive dissection into the right/non-coronary sinuses with acute type A aortic dissection with cardiac tamponade, acute myocardial infarction on the right coronary artery and aortic regurgitation. After total arch replacement with frozen elephant trunk technique for distal dissection, partial root remodeling on the non and right coronary sinuses was performed. Postoperative computed tomography (CT) showed well shaped Valsalva sinuses and aortic regurgitation completely disappeared. This technique might become an alternative procedure for aortic dissection severely involving Valsalva sinuses without dilatation on the aortic root.

2013-01-01

300

Common Iliac Artery Aneurysm and Spontaneous Dissection with Contralateral Iatrogenic Common Iliac Artery Dissection in Classic Ehlers-Danlos Syndrome  

PubMed Central

We describe a 43-year-old man who developed a spontaneous dissection of a right iliac artery aneurysm after performing vigorous physical exercise. Additionally, during peripheral intervention, the patient developed iatrogenic dissection of the left iliac artery. The patient had the characteristic physical findings of Ehlers–Danlos syndrome (EDS), classic type. Genetic testing revealed a mutation in the COL5A1 gene associated with EDS, classic type. Vascular aneurysms and dissections are characteristics of EDS vascular type, but not the classic type. Only one previous case with EDS, classic type with spontaneous iliac artery dissection has been described.

Mehta, Sachin; Dhar, Shweta U.; Birnbaum, Yochai

2012-01-01

301

Common iliac artery aneurysm and spontaneous dissection with contralateral iatrogenic common iliac artery dissection in classic ehlers-danlos syndrome.  

PubMed

We describe a 43-year-old man who developed a spontaneous dissection of a right iliac artery aneurysm after performing vigorous physical exercise. Additionally, during peripheral intervention, the patient developed iatrogenic dissection of the left iliac artery. The patient had the characteristic physical findings of Ehlers-Danlos syndrome (EDS), classic type. Genetic testing revealed a mutation in the COL5A1 gene associated with EDS, classic type. Vascular aneurysms and dissections are characteristics of EDS vascular type, but not the classic type. Only one previous case with EDS, classic type with spontaneous iliac artery dissection has been described. PMID:23997563

Mehta, Sachin; Dhar, Shweta U; Birnbaum, Yochai

2012-09-01

302

A longitudinal study of Type-B aortic dissection and endovascular repair scenarios: computational analyses.  

PubMed

Conservative medical treatment is commonly first recommended for patients with uncomplicated Type-B aortic dissection (AD). However, if dissection-related complications occur, endovascular repair or open surgery is performed. Here we establish computational models of AD based on radiological three-dimensional images of a patient at initial presentation and after 4-years of best medical treatment (BMT). Computational fluid dynamics analyses are performed to quantitatively investigate the hemodynamic features of AD. Entry and re-entries (functioning as entries and outlets) are identified in the initial and follow-up models, and obvious variations of the inter-luminal flow exchange are revealed. Computational studies indicate that the reduction of blood pressure in BMT patients lowers pressure and wall shear stress in the thoracic aorta in general, and flattens the pressure distribution on the outer wall of the dissection, potentially reducing the progressive enlargement of the false lumen. Finally, scenario studies of endovascular aortic repair are conducted. The results indicate that, for patients with multiple tears, stent-grafts occluding all re-entries would be required to effectively reduce inter-luminal blood communication and thus induce thrombosis in the false lumen. This implicates that computational flow analyses may identify entries and relevant re-entries between true and false lumen and potentially assist in stent-graft planning. PMID:23523079

Chen, Duanduan; Müller-Eschner, Matthias; Kotelis, Drosos; Böckler, Dittmar; Ventikos, Yiannis; von Tengg-Kobligk, Hendrik

2013-03-22

303

Global Phosphoproteome Profiling Reveals Unanticipated Networks Responsive to Cisplatin Treatment of Embryonic Stem Cells ? †  

PubMed Central

Cellular responses to DNA-damaging agents involve the activation of various DNA damage signaling and transduction pathways. Using quantitative and high-resolution tandem mass spectrometry, we determined global changes in protein level and phosphorylation site profiles following treatment of SILAC (stable isotope labeling by amino acids in cell culture)-labeled murine embryonic stem cells with the anticancer drug cisplatin. Network and pathway analyses indicated that processes related to the DNA damage response and cytoskeleton organization were significantly affected. Although the ATM (ataxia telangiectasia mutated) and ATR (ATM and Rad3-related) consensus sequence (S/T-Q motif) was significantly overrepresented among hyperphosphorylated peptides, about half of the >2-fold-upregulated phosphorylation sites based on the consensus sequence were not direct substrates of ATM and ATR. Eleven protein kinases mainly belonging to the mitogen-activated protein kinase (MAPK) family were identified as being regulated in their kinase domain activation loop. The biological importance of three of these kinases (cyclin-dependent kinase 7 [CDK7], Plk1, and KPCD1) in the protection against cisplatin-induced cytotoxicity was demonstrated by small interfering RNA (siRNA)-mediated knockdown. Our results indicate that the cellular response to cisplatin involves a variety of kinases and phosphatases not only acting in the nucleus but also regulating cytoplasmic targets, resulting in extensive cytoskeletal rearrangements. Integration of transcriptomic and proteomic data revealed a poor correlation between changes in the relative levels of transcripts and their corresponding proteins, but a large overlap in affected pathways at the levels of mRNA, protein, and phosphoprotein. This study provides an integrated view of pathways activated by genotoxic stress and deciphers kinases that play a pivotal role in regulating cellular processes other than the DNA damage response.

Pines, Alex; Kelstrup, Christian D.; Vrouwe, Mischa G.; Puigvert, Jordi C.; Typas, Dimitris; Misovic, Branislav; de Groot, Anton; von Stechow, Louise; van de Water, Bob; Danen, Erik H. J.; Vrieling, Harry; Mullenders, Leon H. F.; Olsen, Jesper V.

2011-01-01

304

Aortic Diameter >5.5 cm Is Not a Good Predictor of Type A Aortic Dissection Observations From the International Registry of Acute Aortic Dissection (IRAD)  

Microsoft Academic Search

Background—Studies of aortic aneurysm patients have shown that the risk of rupture increases with aortic size. However, few studies of acute aortic dissection patients and aortic size exist. We used data from our registry of acute aortic dissection patients to better understand the relationship between aortic diameter and type A dissection. Methods and Results—We examined 591 type A dissection patients

Linda A. Pape; Thomas T. Tsai; Eric M. Isselbacher; Jae K. Oh; Patrick T. O'Gara; Arturo Evangelista; Rossella Fattori; Gabriel Meinhardt; Santi Trimarchi; Eduardo Bossone; Toru Suzuki; Jeanna V. Cooper; James B. Froehlich; Christoph A. Nienaber; Kim A. Eagle

305

Traumatic Axillary Artery Dissection with Radial Artery Embolism  

SciTech Connect

This report describes a case of pathologically proven traumatic arterial dissection, presenting as complete occlusion of the axillary artery with radial artery embolism. Occlusion of the axillary artery by traumatic dissection mimicked transection and radial artery embolism mimicked congenital absence of the radial artery on the initial angiogram, but these were correctly diagnosed with the following sonogram.

Chung, Hwan-Hoon; Cha, Sang Hoon, E-mail: shcha123@naver.com; Cho, Sung Bum; Kim, Jung Hyuck; Lee, Seung Hwa [Ansan Hospital, Korea University College of Medicine, Department of Radiology (Korea, Republic of); Shin, Jae Seung [Ansan Hospital, Korea University College of Medicine, Department of Thoracic and Cardiovascular Surgery (Korea, Republic of); Park, Sang Woo [KonKuk University Hospital, Department of Radiology (Korea, Republic of)

2006-04-15

306

Therapy Insight: aortic aneurysm and dissection in Marfan's syndrome  

Microsoft Academic Search

Aortic dissection and aneurysm are common clinical problems with life-threatening consequences; they are also the hallmark of several genetic diseases, including Marfan's syndrome (MFS). In spite of clinical and surgical advances that have increased life expectancy for affected patients, cardiovascular manifestations remain significant contributors to morbidity and mortality in MFS. Dissecting aortic aneurysm in this disorder is accounted for by

Harry C Dietz; Francesco Ramirez

2004-01-01

307

Spontaneous dissections of cervicocephalic arteries in childhood and adolescence.  

PubMed

Among 263 consecutive patients with spontaneous cervicocephalic arterial dissections evaluated at the Mayo Clinic, 18 (6.8%) were 18 years of age or younger (mean age, 12 years). The dissection involved the cervical arteries in 11 patients and the intracranial arteries in seven. Extracranially, the internal carotid artery was involved in eight patients, the vertebral artery in two, and both arteries in one. Intracranially, only the anterior circulation was affected. All the patients had cerebral or retinal ischemic symptoms, usually preceded by headache. Death occurred in a 13-year-old boy with intracranial arterial dissection and coarctation of the aorta. For the 17 remaining patients, the follow-up period ranged from 1 to 21 years. A complete or good clinical recovery occurred in 10 of the 11 patients with cervical arterial dissection but in only four of the seven with dissection of intracranial arteries. Recurrent arterial dissection occurred in two patients with cervical arterial dissections and in one patients with intracranial arterial dissection. PMID:7936283

Schievink, W I; Mokri, B; Piepgras, D G

1994-09-01

308

A Modified Dissection Method to Preserve Neck Structures  

ERIC Educational Resources Information Center

|The neck is not only one of the more challenging anatomical regions to dissect but also has important application to clinical conditions, diseases, and procedures. In this study, we describe two simple modifications for dissection of the neck that (1) aid in the identification and preservation of the cutaneous branches of the cervical plexus and…

Hankin, Mark H.; Stoller, Jeremy L.

2009-01-01

309

Predicting death in patients with acute type A aortic dissection  

Microsoft Academic Search

Background—Given the high mortality rates in patients with type A aortic dissection, predictive tools to identify patients at increased risk of death are needed to assist clinicians for optimal treatment. Methods and Results—Accordingly, we evaluated 547 patients with this diagnosis enrolled in the International Registry of Acute Aortic Dissection (IRAD) between January 1996 and December 1999. Univariate testing followed by

Rajendra H. Mehta; Toru Suzuki; Peter G. Hagan

2002-01-01

310

Student Attitudes Toward Cadaveric Dissection at a UK Medical School  

NSDL National Science Digital Library

This article describes a survey conducted among first year medical students examining two main questions. One, attitudes toward the process of dissection and the personhood of the cadaver Two, the extent to which gender, anxiety, exposure to dissection, bereavement and prior experience of a dead body influenced these attitudes. Outcomes and suggestions on how to respond to first year dissectors are provided.

Thelma Quince (University of Cambridge Department of Public Health and Primary Care)

2011-06-08

311

University of Wisconsin Medical School Anatomy Dissection Videos  

NSDL National Science Digital Library

This website provides 27 dissection videos of a human cadaver. Each video focuses on a certain region of the human body and associated anatomical structures. Each video is accompanied by a verbal explanation of the dissection taking place and anatomical structures uncovered. The videos range in time from 6 to 25 minutes in length.

University of Wisconsin Medical School (University of Wisconsin Anatomy)

2002-01-01

312

Internal carotid artery dissection in a patient with Behçet's syndrome.  

PubMed

The authors report a case of internal carotid artery dissection in a young woman with Behçet's syndrome. The authors postulate that a vasculitis of the vasa vasorum already suspected as the basis of aneurysm formation in course of Behçet's syndrome can account for occurrence of arterial dissection in this inflammatory condition. PMID:9732425

Pannone, A; Lucchetti, G; Stazi, G; Corvi, F; Ferguson, T L; Massucci, M; Zaccaria, A

1998-09-01

313

Surgical management of spontaneous left main coronary artery dissection.  

PubMed

Two cases of spontaneous left main coronary artery dissection are reported. This condition is rare and may present as an urgent surgical dilemma. The presentation, diagnosis, and management of primary left main coronary artery dissection are reviewed. Causative factors and underlying pathology are clarified. Prompt diagnosis and surgical intervention with temporary ventricular support is safe and effective. PMID:9692481

Thistlethwaite, P A; Tarazi, R Y; Giordano, F J; Jamieson, S W

1998-07-01

314

Recurrent spontaneous coronary artery dissection: acute management and literature review  

PubMed Central

Spontaneous coronary artery dissection is a rare cause of acute presentations to the catheter laboratory. Often, the angiographic findings are subtle and may be mistaken for a plaque rupture. We descibe a case where repeat presentation revealed the diagnosis of recurrent spontaneous coronary artery dissection.

Dana, Ali

2012-01-01

315

Acute aortic dissection provoked by sneeze: a case report  

Microsoft Academic Search

The response of the abdominal viscera and the contraction of the intercostal muscles during the respiratory phase of sneezing increases intrathoracic pressure, which may lead to several complications. However, there are no reports in the literature concerning aortic dissection after sneezing. We report a patient in whom the development of dissection was secondary to sneezing, although hypertension was present as

A Baydin; M S Nural; H Gu?ven; T Deniz; F Bildik; A Karaduman

2005-01-01

316

A Modified Dissection Method to Preserve Neck Structures  

ERIC Educational Resources Information Center

The neck is not only one of the more challenging anatomical regions to dissect but also has important application to clinical conditions, diseases, and procedures. In this study, we describe two simple modifications for dissection of the neck that (1) aid in the identification and preservation of the cutaneous branches of the cervical plexus and…

Hankin, Mark H.; Stoller, Jeremy L.

2009-01-01

317

Vertebral artery dissection: Issues in diagnosis and management  

Microsoft Academic Search

Vertebral artery dissection is an uncommon cause of stroke in children. Accuracy of diagnosis by magnetic resonance angiography (MRA) instead of invasive transfemoral angiography (TFA) has been controversial. The need for anticoagulation and duration of such therapy is also arguable. We report 2 boys with vertebral artery dissection: one, aged 7 years, presented with hemiparesis and seizures and the other,

Divya S. Khurana; Carsten G. Bonnemann; Elizabeth C. Dooling; Eileen M. Ouellette; Ferdinando Buonanno

1996-01-01

318

Vertebral Artery Dissection and Migraine Headaches in Children  

Microsoft Academic Search

Strokes of the posterior circulation are uncommon in childhood. In vertebrobasilar insults, vertebral artery dissection remains a rare diagnosis. We report the case of an 8-year-old boy with a history of migraine headaches who presented with acute cerebellar signs and agitation following multiple infarctions of bilateral cerebellar hemispheres. Vertebral angiography demonstrated dissection of the left vertebral artery with occlusion of

Timothy E. Lotze; Juliann Paolicchi

2000-01-01

319

Uncommon ultrasound findings in traumatic extracranial vertebral artery dissection  

Microsoft Academic Search

We report a case of internal carotid artery dissection (ICAD) associated with contralateral vertebral artery dissection (VAD). The interest of this case is to discuss an unusual Doppler pattern manifesting by a spectrum of an alternating vertebral artery flow suggesting a hemodynamic contribution from the contralateral vertebral artery (VA) and a clear depiction of both antegrade (red) and retrograde (blue)

N Cals; G Devuyst; D. K Jung; N Afsar; G De Freitas; P-A Despland; J Bogousslavsky

2001-01-01

320

Cervical root injury caused by vertebral artery dissection  

Microsoft Academic Search

Vertebral artery dissection is a common cause of posterior circulation strokes in young and middle-aged adults. Peripheral motor deficits have been rarely described in association with vertebral artery dissection. Peripheral motor involvement may be due to compression of the spinal nerves by an enlarged vertebral artery. It may also result from ischaemia of the anterior horn or the spinal nerves

Arun Aggarwal; Keith Burton

1999-01-01

321

Aortic valve commissural tear mimicking type A aortic dissection  

Microsoft Academic Search

A 52-year-old man came to the local emergency department with symptoms of heart failure and transient chest pain. Transthoracic echocardiography showed severe aortic regurgitation and a dilated ascending aorta. Aortic dissection was suspected, and he was transferred to our institution. Transesophageal echocardiography appeared to confirm the presence of a type A dissection. A mobile, linear structure was present in the

Andrew C. Kupersmith; Robert N. Belkin; John A. McClung; Richard A. Moggio

2002-01-01

322

Aortic Valve Conservation in Acute Type A Dissection  

Microsoft Academic Search

Background. We consider operative survival as the primary objective in acute type A dissection and believe that virtually all native aortic valves can be conserved. We sought to answer the question: “Does glue repair improve the long-term stability of proximal aortic repair?”Methods. We retrospectively studied 64 patients with an acute type A dissection, an ascending aortic tear, and aortic regurgitation

Stephen Westaby; Takahiro Katsumata; Edward Freitas

1997-01-01

323

Dissection of the Adult Zebrafish Kidney  

PubMed Central

Researchers working in the burgeoning field of adult stem cell biology seek to understand the signals that regulate the behavior and function of stem cells during normal homeostasis and disease states. The understanding of adult stem cells has broad reaching implications for the future of regenerative medicine1. For example, better knowledge about adult stem cell biology can facilitate the design of therapeutic strategies in which organs are triggered to heal themselves or even the creation of methods for growing organs in vitro that can be transplanted into humans1. The zebrafish has become a powerful animal model for the study of vertebrate cell biology2. There has been extensive documentation and analysis of embryonic development in the zebrafish3. Only recently have scientists sought to document adult anatomy and surgical dissection techniques4, as there has been a progressive movement within the zebrafish community to broaden the applications of this research organism to adult studies. For example, there are expanding interests in using zebrafish to investigate the biology of adult stem cell populations and make sophisticated adult models of diseases such as cancer5. Historically, isolation of the zebrafish adult kidney has been instrumental for studying hematopoiesis, as the kidney is the anatomical location of blood cell production in fish6,7. The kidney is composed of nephron functional units found in arborized arrangements, surrounded by hematopoietic tissue that is dispersed throughout the intervening spaces. The hematopoietic component consists of hematopoietic stem cells (HSCs) and their progeny that inhabit the kidney until they terminally differentiate8. In addition, it is now appreciated that a group of renal stem/progenitor cells (RPCs) also inhabit the zebrafish kidney organ and enable both kidney regeneration and growth, as observed in other fish species9-11. In light of this new discovery, the zebrafish kidney is one organ that houses the location of two exciting opportunities for adult stem cell biology studies. It is clear that many outstanding questions could be well served with this experimental system. To encourage expansion of this field, it is beneficial to document detailed methods of visualizing and then isolating the adult zebrafish kidney organ. This protocol details our procedure for dissection of the adult kidney from both unfixed and fixed animals. Dissection of the kidney organ can be used to isolate and characterize hematopoietic and renal stem cells and their offspring using established techniques such as histology, fluorescence activated cell sorting (FACS)11,12, expression profiling13,14, and transplantation11,15. We hope that dissemination of this protocol will provide researchers with the knowledge to implement broader use of zebrafish studies that ultimately can be translated for human application.

Wingert, Rebecca A.

2011-01-01

324

Development and application of a phosphoproteomic method using electrostatic repulsion-hydrophilic interaction chromatography (ERLIC), IMAC, and LC-MS/MS analysis to study Marek's Disease Virus infection.  

PubMed

Marek's Disease (MD) is an avian neoplastic disease caused by Marek's Disease Virus (MDV). The mechanism of virus transition between the lytic and latent cycle is still being investigated; however, post-translational modifications, especially phosphorylation, have been thought to play an important role. Previously, our group has used strong cation exchange chromatography in conjunction with reversed-phase liquid chromatography-tandem mass spectrometry (LC-MS/MS) to study the changes in global proteomic expression upon MDV infection (Ramaroson , M. F.; Ruby, J.; Goshe, M. B.; Liu , H.-C. S. J. Proteome Res. 2008, 7, 4346-4358). Here, we extend our study by developing an effective separation and enrichment approach to investigate the changes occurring in the phosphoproteome using electrostatic repulsion-hydrophilic interaction chromatography (ERLIC) to fractionate peptides from chicken embryo fibroblast (CEF) digests and incorporating a subsequent IMAC enrichment step to selectively target phosphorylated peptides for LC-MS/MS analysis. To monitor the multidimensional separation between mock- and MDV-infected CEF samples, a casein phosphopeptide mixture was used as an internal standard. With LC-MS/MS analysis alone, no CEF phosphopeptides were detected, while with ERLIC fractionation only 1.2% of all identified peptides were phosphorylated. However, the incorporation of IMAC enrichment with ERLIC fractionation provided a 50-fold increase in the percentage of identified phosphopeptides. Overall, a total of 581 unique phosphopeptides were identified (p < 0.05) with those of the MDV-infected CEF sample containing nearly twice as many as the mock-infected control of which 11% were unique to MDV proteins. The changes in the phosphoproteome are discussed including the role that microtubule-associated proteins may play in MDV infection mechanisms. PMID:21736374

Chien, Ko-Yi; Liu, Hsiao-Ching; Goshe, Michael B

2011-07-25

325

Gene expression levels assessed by CA1 pyramidal neuron and regional hippocampal dissections in Alzheimer's disease  

PubMed Central

To evaluate molecular signatures of an individual cell type in comparison to the associated region relevant towards understanding the pathogenesis of Alzheimer’s disease (AD), CA1 pyramidal neurons and the surrounding hippocampal formation were microaspirated via laser capture microdissection (LCM) from neuropathologically confirmed AD and age-matched control (CTR) subjects as well as from wild type mouse brain using single population RNA amplification methodology coupled with custom-designed microarray analysis with real-time quantitative polymerase-chain reaction (qPCR) validation. CA1 pyramidal neurons predominantly displayed downregulation of classes of transcripts related to synaptic transmission in AD versus CTR. Regional hippocampal dissections displayed downregulation of several overlapping genes found in the CA1 neuronal population related to neuronal expression, as well as upregulation of select transcripts indicative of admixed cell types including glial-associated markers and immediate-early and cell death genes. Gene level distributions observed in CA1 neurons and regional hippocampal dissections in wild type mice paralleled expression mosaics seen in postmortem human tissue. Microarray analysis was validated in qPCR studies using human postmortem brain tissue and CA1 sector and regional hippocampal dissections obtained from a mouse model of AD/Down syndrome (Ts65Dn mice) and normal disomic (2N) littermates. Classes of transcripts that have a greater percentage of the overall hybridization signal intensity within single neurons tended to be genes related to neuronal communication. The converse was also found, as classes of transcripts such as glial-associated markers were under represented in CA1 pyramidal neuron expression profiles relative to regional hippocampal dissections. These observations highlight a dilution effect that is likely to occur in conventional regional microarray and qPCR studies. Thus, single population studies of specific neurons and intrinsic circuits will likely yield informative gene expression profile data that may be subthreshold and/or under represented in regional studies with an admixture of cell types.

Ginsberg, Stephen D.; Alldred, Melissa J.; Che, Shaoli

2011-01-01

326

Recurrent spontaneous coronary artery dissection: A case report and review of the literature  

PubMed Central

Spontaneous coronary artery dissection is a rare cause of acute coronary syndrome. Recurrent spontaneous dissection is even more rare. A case of recurrent coronary artery dissection is reported and the literature is reviewed.

Harris, Jacqueline L; Brereton, John; Lim, Cathy S; Nelson, Gregory IC

2007-01-01

327

Spontaneous left main dissection treated by percutaneous coronary intervention.  

PubMed

Spontaneous coronary artery dissection is a rare cause of acute coronary events or sudden cardiac death. The clinical presentation is highly variable and prognosis varies widely, depending mainly on how rapidly it is diagnosed. Prompt treatment is also essential, and includes medical management, percutaneous coronary intervention and surgical revascularization. We describe the case of a young woman presenting with spontaneous coronary artery dissection of the left main coronary artery, first diagnosed as coronary thrombus, who underwent successful percutaneous coronary stenting. This report highlights the need to include spontaneous coronary artery dissection in differential diagnosis of chest pain in young women and that distinguishing between coronary thrombus and coronary artery dissection is not always straightforward. To our knowledge this is the fourth case of left main stenting in a patient with spontaneous coronary artery dissection described in the literature. PMID:23809628

Sousa, Alexandra; Lopes, Ricardo; Silva, João Carlos; Maciel, M Júlia

2013-06-25

328

Dissecting aortic aneurysms: accuracy of computed tomographic diagnosis  

SciTech Connect

During a three-year period, fifty patients were evaluated for the possibility of dissecting aortic aneurysm using high-resolution computed tomography (CT). The diagnosis of dissection was made if two contrast-medium-filled channels were identified within the aortic lumen. Eighteen patients were diagnosed with CT as having dissecting aortic aneurysms. Eight patients were evaluated postoperatively and five of these patients had persistence of the double channel. Twenty-four patients had no evidence on CT of aortic dissection. Follow-up was obtained in all patients. There were no known false-negative diagnoses and one false-positive diagnosis. High-resolution CT offers an accurate, noninvasive means to evaluate patients for suspected dissecting aortic aneurysms.

Thorsen, M.K.; San Dretto, M.A.; Lawson, T.L.; Foley, W.D.; Smith, D.F.; Berland, L.L.

1983-09-01

329

Cervical Artery Dissection: Emerging Risk Factors  

PubMed Central

Cervical artery dissection (CAD) represents an increasingly recognized cause of stroke and the most common cause of ischemic stroke in young adults. Many factors have been identified in association with CAD such as primary disease of arterial wall (fibrodysplasia) and other non-specific diseases related to CAD like Ehlers Danlos-syndrome IV, Marfan’s syndrome, vessel tortuosity. Moreover, an underlying arteriopathy which could be in part genetically determined, has been suspected. The rule of emerging risk factors for CAD such as recent respiratory tract infection, migraine and hyperhomocysteinemia are still a matter of research. Other known risks factors for CAD are major head/neck trauma like chiropractic maneuver, coughing or hyperextension injury associated to car. We examined emerging risks factors for CAD detected in the last years, as CAD pathogenesis is still not completely understood and needs further investigations.

Micheli, S; Paciaroni, M; Corea, F; Agnelli, G; Zampolini, M; Caso, V

2010-01-01

330

Diamondiferous Peridotite Tomography: Precursor to Xenolith Dissections.  

NASA Astrophysics Data System (ADS)

Three-dimensional, high-resolution computed X-ray tomography (HRCXT) of diamondiferous peridotite xenoliths from Siberia has successfully imaged diamonds and their textural relationships with co-existing minerals. This is an extension to the tomography and xenolith dissections performed previously on diamondiferous eclogites (e.g., Taylor et al., 2000, Int'l Geol Rev 42; Anand et al., 2003, 8th Int'l Kimb Conf). Spatial relationships between diamonds and their surroundings provide clues to the processes that control diamond crystallization. These relationships can be determined by rotating and viewing the 3-D model at different perspectives and orientations to look for specific associations/alignments. It is possible to render some of the phases transparent and display only one or two minerals at a time. Then by rotating the model, it is possible to look for spatial relationships between different crystals of the same mineral or different minerals. The maps obtained from the tomography form the basis for the delicate dissections of the xenoliths, revealing the diamonds as they formed in their mantle host rocks. Diamondiferous peridotites appear to be sparse carriers of diamonds compared to eclogites, where one unusual eclogite of 65 g contained 74 macro-diamonds. Although kimberlites always contain considerably more peridotite xenoliths than eclogites, the diamond population may actually be more indicative of eclogitic origin. The diamonds appear to be preferentially located in zones with a prominent sub-planar fabric of secondary mineralization - i.e., zones of increased permeability. Diamond was never observed in direct contact with any fresh, primary minerals. Also, there is insufficient sulfide mineralization to call upon an immiscible-sulfide melt as the diamond-forming medium. The association of the diamonds with secondary minerals strongly suggests that the diamonds formed after the initial host peridotite or eclogite, perhaps in conjunction with introduction of metasomatic fluids.

Taylor, L. A.; Taylor, D. S.; Anand, M.; Ketcham, R.; Carlson, W.; Sobolev, N. V.; Pokhilenko, N.

2003-12-01

331

Isolated dissections and dissecting aneurysms of the posterior inferior cerebellar artery: topic and literature review  

Microsoft Academic Search

.  \\u000a Isolated dissections of the posterior inferior cerebellar artery (PICA) are rare. Thus, no large series of cases have been\\u000a reported in the literature. Due to limited knowledge regarding the natural history of these lesions and the lack of high-quality\\u000a evidence supporting various treatment options, management is controversial and practice parameters are ill defined. In order\\u000a to offer a comprehensive

Rabih G. Tawk; Bernard R. Bendok; Adnan I. Qureshi; Christopher C. Getch; Jayashree Srinivasan; Mark Alberts; Eric J. Russell; H. Hunt Batjer

2003-01-01

332

Quantitative Phosphoproteome Analysis of Lysophosphatidic Acid Induced Chemotaxis applying Dual-step ¹O Labeling Coupled with Immobilized Metal-ion Affinity Chromatography  

Microsoft Academic Search

Reversible protein phosphorylation is a central cellular regulatory mechanism in modulating protein activity and propagating signals within cellular pathways and networks. Development of more effective methods for the simultaneous identification of phosphorylation sites and quantification of temporal changes in protein phosphorylation could provide important insights into molecular signaling mechanisms in a variety of different cellular processes. Here we present an

Shi-Jian Ding; Yingchun Wang; Jon M. Jacobs; Wei-Jun Qian; Feng Yang; Aleksey V. Tolmachev; Xiuxia Du; Wei Wang; Ronald J. Moore; Matthew E. Monroe; Samuel O. Purvine; Katrina M. Waters; Tyler H. Heibeck; Joshua N. Adkins; David G. Camp; Richard L. Klemke; Richard D. Smith

2008-01-01

333

Exploring the human leukocyte phosphoproteome using a microfluidic reversed-phase-TiO2-reversed-phase high-performance liquid chromatography phosphochip coupled to a quadrupole time-of-flight mass spectrometer.  

PubMed

The study of protein phosphorylation events is one of the most important challenges in proteome analysis. Despite the importance of phosphorylation for many regulatory processes in cells and many years of phosphoprotein and phosphopeptide research, the identification and characterization of phosphorylation by mass spectrometry is still a challenging task. Recently, we introduced an approach that facilitates the analysis of phosphopeptides by performing automated, online, TiO(2) enrichment of phosphopeptides prior to mass spectrometry (MS) analysis. The implementation of that method on a "plug-and-play" microfluidic high-performance liquid chromatography (HPLC) chip design will potentially open up efficient phosphopeptide enrichment methods enabling phosphoproteomics analyses by a broader research community. Following our initial proof of principle, whereby the device was coupled to an ion trap, we now show that this so-called phosphochip is capable of the enrichment of large numbers of phosphopeptides from complex cellular lysates, which can be more readily identified when coupled to a higher resolution quadrupole time-of-flight (Q-TOF) mass spectrometer. We use the phosphochip-Q-TOF setup to explore the phosphoproteome of nonstimulated primary human leukocytes where we identify 1012 unique phosphopeptides corresponding to 960 different phosphorylation sites providing for the first time an overview of the phosphoproteome of these important circulating white blood cells. PMID:20058876

Raijmakers, Reinout; Kraiczek, Karsten; de Jong, Ad P; Mohammed, Shabaz; Heck, Albert J R

2010-02-01

334

Genetic dissection of agronomic traits within a segregating population of breeding table grapes.  

PubMed

Grapes (Vitis vinifera) are of great economic importance worldwide. We genetically dissected a table grape breeding population, using hidden Markov models (HMM) applied to quantitative trait locus (QTL) analyses. We evaluated and dissected the following traits: total number of clusters, leaf score, peduncle length, cluster length, number of berries, weight of 10 berries, average seed number, nature of seeds, berry skin color, soluble solids, titratable acidity, and berry anthocyanin. A consensus map was developed with 255 SSR molecular markers, ordered into 19 linkage groups. The observed length of this map was 1871.4 cM, with 89.7% coverage. QTL were identified using interval mapping with HMM. The number of QTL detected for each trait varied between 1 and 8, reflecting the quantitative nature of these traits. The percentage of variation explained by these QTL was small, varying between 1.56 and 11.98%. We found QTL across linkage groups 2, 7, 12, 13, and 14 for berry anthocyanin. PMID:23613241

Viana, A P; Riaz, S; Walker, M A

2013-04-02

335

QUANTITATIVE MORPHOLOGY  

EPA Science Inventory

Abstract: In toxicology, the role of quantitative assessment of brain morphology can be understood in the context of two types of treatment-related alterations. One type of alteration is specifically associated with treatment and is not observed in control animals. Measurement ...

336

Endoscopic Extracapsular Dissection for Resection of Pituitary Macroadenomas: Technical Note.  

PubMed

Objective?With the increasing use of the endoscope in neurosurgery, transsphenoidal surgery has undergone a considerable technical evolution. However, most recently reported advances relate to the approach to the sella turcica or to extended transsphenoidal approaches, whereas the dissection technique for pituitary tumor removal itself has received more limited attention. A notable exception is Oldfield's elegant description of an extracapsular dissection of functional pituitary microadenomas. Our objective is to describe and illustrate our technique for endoscopic extracapsular resection of pituitary macroadenomas.Methods?Influenced by Oldfield's description, we have adopted an extracapsular dissection technique in the endoscopic resection of pituitary macroadenomas. After carefully opening the dura without disrupting the macroadenoma pseudocapsule, the pseudocapsule is dissected inferiorly and laterally. The tumor is then internally debulked and the extracapsular dissection is extended circumferentially; the resection is then complete.Results?The enhanced visualization and illumination afforded by the endoscope enables the identification and surgical dissection of the pseudocapsule at the periphery of the macroadenomas under direct vision in most cases. As demonstrated in the illustrative case, working around the macroadenoma pseudocapsule allows for a definitive and complete macroadenoma resection with direct visual confirmation and with preservation of the normal gland and diaphragma.Conclusion?The endoscopic transsphenoidal approach permits an extracapsular dissection of many pituitary macroadenomas. In our preliminary experience, this technique appears to result in a high rate of complete resection without an increase in complications. PMID:23034885

Chamoun, Roukoz; Takashima, Masayoshi; Yoshor, Daniel

2012-10-01

337

Sequential multiple visceral arteries dissections without aortic involvement.  

PubMed

Isolated dissection of visceral arteries without associated aortic pathology is very rare. Risk factors, etiology, and natural history of this pathology continue to be unclear, and the guidelines for clinical management remain to be defined. We present a case not described previously, with sequential dissections of the celiac trunk, superior mesenteric artery, and renal arteries without aortic involvement. The patient presented with severe back thoracic and abdominal pain and without evidence of peritonitis. An abdominal angio-CT scan showed dissection of the superior mesenteric artery (SMA), with partial thrombosis of the false lumen and subsequent stenosis of around 60%. Conservative treatment with anticoagulants seemed to be appropriate in the beginning, because the patient became asymptomatic spontaneously within a few hours and angio-CT showed dissection but no ischemic lesions. On day 10 after onset, however, he again indicated severe back thoracic and abdominal pain. Emergent CT was performed. The prior SMA dissection appeared to be worse due to increased size of the false lumen, followed by SMA stenosis (about 75?80%). In addition, dissection of the celiac artery and both renal arteries could be seen. The patient underwent angiography and stenting of the main trunk of the SMA, with good clinical and radiologic outcome. Double oral antiplatelet therapy was then introduced. An angio-MRI scan 6 months later showed stability of the multiple dissections. PMID:23522441

Bonardelli, Stefano; Battaglia, Giuseppe; Zanotti, Camilla; Cervi, Edoardo; Guadrini, Cristina; Giulini, Stefano M

2013-03-20

338

Level V in therapeutic neck dissections for papillary thyroid carcinoma.  

PubMed

Neck dissection for papillary thyroid carcinoma (PTC) is the standard of care for patients with clinical evidence of regional metastases. However, the extent of neck dissection is debatable. The purpose of the current study was to develop evidence-based recommendations for when to include level V, or 1 of its sublevels, among patients with PTC undergoing neck dissection. A literature review of all studies evaluating the occurrence of metastases in level V in patients with regional metastases from PTC undergoing neck dissection was performed. Occurrence of metastases at level V is low in most series (5% to 10%), although a wide range was noticed. In cases in which metastases were found at level V, they occurred almost exclusively at sublevel VB. Sublevel VA was rarely, if ever, involved with metastatic lymph nodes. However, only recently have investigators begun to specify which sublevels of level V are at risk. Therapeutic dissection of level V is indicated when there is clinical evidence of disease involving this zone. Elective dissection of sublevel VB is indicated when there is involvement of level IV, or possibly multiple nodes at levels II and III. Under these circumstances, dissection of sublevel VB is indicated but sublevel VA may be spared. PMID:22287259

Khafif, Avi; Medina, Jesus E; Robbins, K Thomas; Silver, Carl E; Weber, Randal S; Rinaldo, Alessandra; Owen, Randall P; Shaha, Ashok R; Ferlito, Alfio

2012-01-27

339

Cranial nerve palsies in spontaneous carotid artery dissection.  

PubMed Central

Two patients had isolated unilateral cranial nerve palsies due to spontaneous internal carotid artery (ICA) dissection without ischaemic cerebral involvement. One had acute glossopharyngeal and vagal, the other isolated hypoglossal nerve palsy. Reviewing all reported cases of angiographically confirmed ICA dissection in the literature, 36 additional cases with unequivocal ipsilateral cranial nerve palsies were analysed. While an isolated palsy of the IXth and Xth has not been reported previously, palsies of the XIIth nerve or the IXth to XIIth nerves were most frequently found. In these patients, lower cranial nerve palsies are probably the result of compression by an enlarging ICA due to mural haematoma. Symptoms and signs indicative of carotid dissection were concurrently present only in some reported cases. This raises the question of unrecognised carotid dissection as a cause of isolated cranial nerve palsies. When the dissection occurs in the subadventitial layer without relevant narrowing of the arterial lumen and when an aneurysm is thrombosed, angiography does not reliably yield the diagnosis. Therefore, carotid dissection might have been underestimated as a cause of isolated lower cranial nerve palsies before the advent of MRI. MRI demonstrates directly the extension of the wall haematoma in the axial and longitudinal planes. Some arteriopathies such as fibromuscular dysplasia and tortuosity make a vessel predisposed to dissection. Images

Sturzenegger, M; Huber, P

1993-01-01

340

[Dissection of the extracranial vertebral artery: a case report].  

PubMed

Spontaneous dissection of the vertebral artery is not a frequent occurrence in the vertebrobasilar system. The authors show a case with spontaneous dissection of the extracranial vertebral artery, which produced recurrent artery-to-artery embolism. The angiography revealed characteristic intimal flap. The antiplatelet and anticoagulant therapy was able to control ischemic attacks and the patient made a good clinical recovery. The angiogram performed two months later showed spontaneous resolution of the artery involved. This case shows the effectiveness of anticoagulation and antiplatelet therapy for the prevention of artery-to-artery embolism caused by the extracranial vertebral artery dissection. PMID:7816181

Ishikawa, A; Kanazawa, Y; Hikasa, T; Fujita, K; Tamaki, N

1994-11-01

341

Ascending aortic dissection in weight lifters with cystic medial degeneration.  

PubMed

We report 4 cases of ascending aortic dissection in patients with long histories of weight lifting. In 2 of the patients, the initial symptoms of dissection developed while they were lifting weights. Two patients had a history of hypertension and 2 had previously used anabolic steroids. All 4 were successfully treated surgically. Histopathology showed aortic medial changes in all 4. We believe that the hemodynamic stresses of weight lifting, namely, a rapid increase in systemic arterial blood pressure without a decrease in total peripheral vascular resistance, in combination with aortic medial degeneration may have contributed to the development of the aortic dissection. PMID:2322060

de Virgilio, C; Nelson, R J; Milliken, J; Snyder, R; Chiang, F; MacDonald, W D; Robertson, J M

1990-04-01

342

Traumatic carotid artery dissection caused by bungee jumping.  

PubMed

Bungee jumping is a popular recreational activity in which participant experiences transient freefall while connected to a bungee cord. The rapid freefall and the resultant rebound force created by the bungee cord can result in a variety of bodily injuries. We report herein a case of traumatic carotid artery dissection caused by bungee jumping. The symptoms related to carotid artery dissection were successfully treated with anticoagulation. The etiology of carotid dissection related to bungee jumping is discussed. Physicians should be cognizant of this potential injury due to the force created by the freefall and rebound motion associated in this recreational sport. PMID:17980290

Zhou, Wei; Huynh, Tam T; Kougias, Panagiotis; El Sayed, Hosam F; Lin, Peter H

2007-11-01

343

Hybrid nuclear dissection technique for capsular bag phacoemulsification.  

PubMed

A bimanual phacoemulsification technique for dissecting and removing the firm lens nucleus is described. The technique is a surgical hybrid that combines concepts developed by several surgeons. Bimanual posterior and peripheral nuclear bowl fiber separation (nuclear fracture) has been incorporated into the anatomic dissection of the lens within the capsular bag. This dissection is accomplished with the 45-degree tip on separated nuclear components in situ after capsulorhexis. Combining the best features of various techniques permits this hybrid method to be applied to firm cataracts by most surgeons currently performing phacoemulsification. PMID:2380924

Davison, J A

1990-07-01

344

Spontaneous coronary artery dissection presenting as cardiac tamponade.  

PubMed

Spontaneous dissection of the left main coronary artery is the least common of all dissections involving the coronary arteries. It usually occurs in young women, especially in the peripartum or early postpartum period. We describe the case of a 59-year-old man with no previous history of atherosclerotic heart disease who presented in cardiac tamponade and was found to have a spontaneous left main stem coronary artery dissection at cardiac catheterization. Emergency revascularization was carried out with the patient remaining symptom-free 4 months after surgery. PMID:11996290

Badmanaban, Balaji; McCarty, David; Mole, Damian J; McKeown, Pascal P; Sarsam, Mazin A I

2002-04-01

345

Applications of quantitative whole body autoradiographic technique in radiopharmaceutical research  

SciTech Connect

The routine evaluation of radiopharmaceuticals involves dissecting tissue distribution studies (DTDS) and gamma or positron imaging. DTDS have the following disadvantages: since not all tissues can always be sampled, sites of radiopharmaceutical uptake may be missed and because the procedure involves weighing of dissected tissue samples, the spatial resolution of this method is low and determined by the smallest amount that can be weighed accurately. Gamma camera imaging and positron emission tomography though more comprehensive in evaluating the global distribution of a compound, have relative low spatial resolution. Whole body autoradiography of small animals has a much higher spatial resolution as compared to the above and depicts the global distribution of radiopharmaceuticals. A computer-assisted quantification method of WBARG applied to positron, beta, and gamma emitters will complement the method by producing quantitative values comparable to those obtained by dissection and direct tissue counting, with the advantages of depicting the global distribution at high spatial resolution.

Som, P.; Oster, Z.H.; Yonekura, Y.; Meyer, M.A.; Fand, I.; Brill, A.B.

1982-01-01

346

Dissecting soil moisture-precipitation coupling  

NASA Astrophysics Data System (ADS)

The ability of soil moisture to affect precipitation (SM-P) can be dissected into the ability of soil moisture to affect evapotranspiration (ET; SM-ET) and the ability of ET to affect precipitation (ET-P). SM-ET is a local process that is relatively easy to quantify, but ET-P includes nonlocal atmospheric processes and is more complex. Here, ET-P is quantified both locally and remotely with a back-trajectory method for water vapor transport, using corrected reanalysis data. It is found that, for SM-P and ET-P, local impact is greater than that from remote for most land areas with significant local impacts. By examining the responses of the three metrics (SM-ET, ET-P, and SM-P) to climate variations over different climate regimes, we show that SM-ET is the principal factor that determines the spatial pattern and variation of SM-P. For climatologically wet regions, SM-ET and SM-P are higher during dry periods, and vice versa for climatologically dry regions. All three metrics show highest values over the transitional zones.

Wei, Jiangfeng; Dirmeyer, Paul A.

2012-10-01

347

Complications of gastric endoscopic submucosal dissection.  

PubMed

Endoscopic resection is now a widely accepted treatment for early gastric cancer, having a negligible risk of lymph-node metastasis. Endoscopic submucosal dissection (ESD) is a relatively new endoscopic resection method developed in the mid-1990 s that facilitates en-bloc resection even in patients with large or ulcerative lesions difficult to resect using conventional endoscopic mucosal resection (EMR). However, compared to EMR, ESD requires a longer procedure time and a higher level of technical expertise, in addition to having a slightly greater risk of complications. Endoscopists must be aware of not only the risk factors for, and incidence of, complications, but also how to effectively treat such complications. Perforation and bleeding are the major complications associated with gastric ESD. The perforation and delayed bleeding rates have been reported to range from 1.2% to 5.2% and 0% to 15.6%, respectively, and can usually be managed with appropriate endoscopic treatment. Immediate bleeding during gastric ESD is quite common and controlling such bleeding, which is primarily achieved by carrying out electrocautery, plays a critical role in the successful completion of ESD. PMID:23368986

Oda, Ichiro; Suzuki, Haruhisa; Nonaka, Satoru; Yoshinaga, Shigetaka

2013-01-24

348

Single Drosophila ommatidium dissection and imaging.  

PubMed

The fruit fly Drosophila melanogaster has made invaluable contributions to neuroscience research and has been used widely as a model for neurodegenerative diseases because of its powerful genetics(1). The fly eye in particular has been the organ of choice for neurodegeneration research, being the most accessible and life-dispensable part of the Drosophila nervous system. However the major caveat of intact eyes is the difficulty, because of the intense autofluorescence of the pigment, in imaging intracellular events, such as autophagy dynamics(2), which are paramount to understanding of neurodegeneration. We have recently used the dissection and culture of single ommatidia(3) that has been essential for our understanding of autophagic dysfunctions in a fly model of Dentatorubro-Pallidoluysian Atrophy (DRPLA)(3, 4). We now report a comprehensive description of this technique (Fig. 1), adapted from electrophysiological studies(5), which is likely to expand dramatically the possibility of fly models for neurodegeneration. This method can be adapted to image live subcellular events and to monitor effective drug administration onto photoreceptor cells (Fig. 2). If used in combination with mosaic techniques(6-8), the responses of genetically different cells can be assayed in parallel (Fig. 2). PMID:21876525

Volpi, Vera; Mackay, Daniel; Fanto, Manolis

2011-08-19

349

The need for lymph node dissection in nonmetastatic breast cancer.  

PubMed

Determining whether cancer has spread to locoregional lymph nodes is a critical step in the initial staging of breast cancer patients. Although axillary dissection reliably identifies nodal metastases and prevents the recurrence of cancer in the axilla, there is a significant incidence of long-term side effects, notably lymphedema, and the procedure is of no therapeutic benefit in women without axillary metastases. With the advent of sentinel lymph node biopsy, the axilla can be accurately staged in patients with T1-T3, clinically node-negative breast cancers while avoiding the morbidity of axillary lymph node dissection if the nodes do not contain cancer. Recent clinical trials suggest that for women with metastases to 1 or 2 sentinel nodes, the radiation and systemic therapy that are part of modern multimodality breast cancer treatment can replace axillary dissection when breast-conserving therapy is undertaken. For those with greater disease burden or those undergoing mastectomy, axillary dissection remains standard management. PMID:23020881

Pesce, Catherine; Morrow, Monica

2012-09-27

350

Spontaneous coronary artery dissection presenting as acute myocardial infarction.  

PubMed Central

Spontaneous coronary artery dissection is a rare entity being increasingly diagnosed as a cause of acute myocardial infarction, especially in cases of low cardiac risk female patients. This is one such case report of a black female patient, who suffered an acute anterior wall myocardial infarction due to an idiopathic spontaneous coronary artery dissection of the left anterior descending artery. She was treated with a thrombolytic agent in the acute phase, uneventfully. An urgent coronary angiogram demonstrated an intimal tear with a dissection of the left anterior descending artery. She survived the acute event and her subsequent hospital course was uncomplicated. Hence she was treated medically for her ischemic event and left ventricular systolic dysfunction with a favorable outcome. This case is yet another report of a survivor treated with a thrombolytic agent for the acute myocardial infarction due to spontaneous coronary artery dissection. Images Figure 2 Figure 3

Mahenthiran, J.; Revankar, R.; Koka, V.; Hoo, J.; Shenoy, M.

2000-01-01

351

Aortic dissection presenting as gait disturbance: a case report.  

PubMed

Emergency medicine dogma traditionally teaches that aortic dissection presents as tearing chest pain, radiating to the back. This case report describes a 55-year-old woman presenting with a left homonymous hemianopsia and resultant gait disturbance. Initial head computed tomography demonstrated a right parietal infarct, and chest radiograph demonstrated a markedly widened mediastinum. Acute Stanford type A aortic dissection was subsequently confirmed. This report provides further evidence for atypical, painless presentations of aortic dissection. Given recent literature on the increasing prevalence of painless dissection, the disease entity should be included in the differential diagnosis for stroke, and a simple portable chest x-ray should always be obtained before administering thrombolytics. PMID:22742952

Estreicher, Michael; Portale, Joseph; Lopez, Bernard

2012-06-27

352

[Spontaneous dissection and stenosis of the vertebral artery].  

PubMed

The case of a 21-year-old female patient with neck pain and brain stem symptomatology after appendectomy is reported. Duplex sonographic findings were compatible with right vertebral artery dissection and occlusion of the vessel. Angiography confirmed the diagnosis. The patient recovered within weeks and was free of symptoms 6 months after the acute episode. Dissection of the vertebral artery can occur with or without minor trauma. Associations with fibromuscular dysplasia, arterial hypertension and the use of oral contraceptives have been reported. As in our own patient, dissection can appear without any vessel pathology or risk situation. The most dangerous complication of the disease is rupture of the adventitia with subarachnoid hemorrhage. Without this complication, prognosis of vertebral artery dissection is favourable with complete recovery within weeks. Clinical findings, diagnostic procedure and therapy are discussed. PMID:1925454

Frauchiger, B; Bernays, D R

1991-08-31

353

[Cervical deficit radiculopathy in 3 cases of vertebral artery dissection].  

PubMed

Three cases of extracranial vertebral artery dissections with upper limb peripheral motor deficit (C5-C6) are reported. Six similar cases were also found in the literature. Central neurological symptoms occurred in five of these nine cases, suggesting the diagnosis of dissection. The peripheral motor or sensorial deficit was strictly isolated in the four other cases, simulating radicular neuralgia due to discopathy or foraminal compression. In case of dissections, a precise analysis of pain is helpful to guide diagnosis; sharp, unbearable, continuous and extended neck pain without nocturnal paroxysms and posterior neck stiffness is typical. Analgesics or anti-inflammatory drugs are ineffective. Peripheral motor deficit is more common than sensory deficit. Recovery was complete in this series. In most cases, the radiculopathy appears to be due to cervical root compression in its extraforaminal course due to the dissection hematoma and rarely to radicular ischemia. PMID:9894290

de Bray, J M; Penisson-Besnier, I; Giroud, M; Klein, J; Tanguy, J Y; Pasco, A; Dubas, F

1998-11-01

354

Spontaneous Coronary Artery Dissection: Not Just a Heart Attack  

MedlinePLUS

Spontaneous Coronary Artery Dissection: Not Just a Heart Attack Updated:Jul 27,2013 Sometimes a heart attack is not just a ... the result of spontaneous tearing in the coronary artery wall. The artery wall has three layers and ...

355

Non-invasive diagnosis of internal carotid artery dissections.  

PubMed Central

Arteriography is thought to be mandatory for the diagnosis of internal carotid artery (ICA) dissection. With the introduction of transcranial Doppler sonography (TCD) and magnetic resonance imaging (MRI), however, this is no longer the case. In 13 consecutive patients with ICA dissections the diagnosis was made by means of non-invasive tests including extracranial and transcranial Doppler sonography, contrast enhanced computed tomography (ceCT), and, in five patients, MRI. Intra-arterial digital subtraction angiography used as the gold standard in all cases was confirmative. Extracranial and transcranial ultrasound findings indicative of the diagnosis could be identified. MRI directly demonstrated the intramural haematoma and the false lumen of the dissected artery. These non-invasive techniques also allowed for repetitive follow up examinations. They were, however, unable to demonstrate false aneurysms in the chronic state. Results show that the diagnosis of carotid dissection can be made by means of cerebrovascular ultrasound and MRI. Images

Mullges, W; Ringelstein, E B; Leibold, M

1992-01-01

356

Laparoscopic Pelvic and Paraaortic Lymph Node Dissection in the Obese  

Microsoft Academic Search

Objective. The aim of this study was to determine the utility of laparoscopic pelvic and paraaortic lymph node dissection in obese women.Methods. We performed a retrospective analysis from 1\\/8\\/96 to 1\\/14\\/01 at the University of Oklahoma Health Science Center, evaluating patients who had a Quetelet index (QI) ?28 and had planned laparoscopic bilateral pelvic and paraaortic lymph node dissections (lnd)

Dennis R. Scribner Jr.; Joan L. Walker; Gary A. Johnson; D. Scott McMeekin; Michael A. Gold; Robert S. Mannel

2002-01-01

357

Peripartum acute aortic dissection: A case report & review of literature.  

PubMed

Acute aortic dissection is a rare clinical entity that mainly affects patients older than 50 years. It is unusual in younger patients and its presence has been traditionally associated with trauma, Marfan syndrome, bicuspid aortic valve and pregnancy. We present here, a case of a 30 year old pregnant female with acute aortic dissection type A (De Bakey II), without family history of connective tissue diseases and signs of Marfan syndrome. PMID:22263062

Aziz, Fahad; Penupolu, Sudheer; Alok, Anshu; Doddi, Sujatha; Abed, Mary

2011-03-01

358

Cervical cerebral artery dissection: a multicenter prospective study (preliminary report)  

Microsoft Academic Search

Forty-nine cases of dissection of the internal carotid and vertebral arteries are reported in our prospective multicenter study of 35 men and 14 women, with a mean age of 46.77 years. (range 17–60 years). We evaluated etiology, clinical manifestations, investigative techniques, and treatment. Thirty-one patients had so-called spontaneous dissections, although in the remaining 18 minimal or obvious trauma was considered

P. Bassi; P. Lattuada; A. Gomitoni

2003-01-01

359

Dissecting Aneurysm of the Peripheral Posterior Inferior Cerebellar Artery  

Microsoft Academic Search

Summary  ¶?Dissecting aneurysms of intracranial posterior circulation have recently been shown to be less uncommon than previously\\u000a thought. However, those involving the posterior inferior cerebellar artery (PICA) and not vertebral artery at all are extremely\\u000a rare. We report here a case of a patient with a dissecting aneurysm of the lateral medullary segment of PICA which presented\\u000a as subarachnoid haemorrhage. The

Y. Kanou; K. Arita; K. Kurisu; F. Ikawa; K. Eguchi; S. Monden; K. Watanabe

2000-01-01

360

Endovascular Treatment of Iatrogenic and Traumatic Carotid Artery Dissection  

Microsoft Academic Search

This paper reports on the early and midterm results of endovascular treatment of acute carotid artery dissections, its specific\\u000a problems, and its limitations. We encountered seven patients with symptomatic extracranial carotid artery dissection, three\\u000a cases of which occurred after carotid endarterectomy, two after carotid angioplasty and stenting, and two after trauma. Balloon-expandable\\u000a and self-expanding stents were placed using a transfemoral

Stefan Schulte; Konstantinos P. Donas; Georgios A. Pitoulias; Svante Horsch

2008-01-01

361

Stroke prevention and treatment in patients with spontaneous carotid dissection  

Microsoft Academic Search

This review on spontaneous dissection of the internal carotid artery (sICAD) will discuss in the first part stroke prevention\\u000a and focus on vascular risk factors, antithrombotic therapy, and treatment of severe stenosis or occlusion, and dissecting\\u000a aneurysm. The second part of the review will summarize the treatment of acute ischemic stroke due to sICAD.

Ralf W. Baumgartner

362

Vertebral artery dissection in rheumatoid arthritis with cervical spine disease.  

PubMed

A 59-year-old woman with long-standing active rheumatoid arthritis presented with posterior circulation ischemic stroke after vertebral dissection. She had severe multilevel degenerative changes of her cervical spine. She did not have classic stroke risk factors nor evidence of atherosclerotic disease or other systemic diseases. The most likely mechanism appears to be injury of the artery wall by an osteophyte, causing dissection that resulted in thrombosis and subsequent embolic strokes. PMID:23352423

Mahajan, Ritika; Huisa, Branko N

2013-01-23

363

Internal carotid artery dissection associated with scuba diving.  

PubMed

A 52-year-old man presented to the emergency department with dysphasia and a headache after scuba diving. He was treated initially for decompression sickness. Subsequent workup revealed bilateral internal carotid artery dissection. The risk factors, presenting symptoms, diagnosis, and treatment of internal carotid artery dissection are reviewed. The importance of considering unusual causes of neurologic deficits after scuba diving is emphasized. PMID:7802358

Nelson, E E

1995-01-01

364

Internal Carotid Artery Dissection Associated With Scuba Diving  

Microsoft Academic Search

A 52-year-old man presented to the emergency department with dysphasia and a headache after scuba diving. He was treated initially for decompression sickness. Subsequent workup revealed bilateral internal carotid artery dissection. The risk factors, presenting symptoms, diagnosis, and treatment of internal carotid artery dissection are reviewed. The importance of considering unusual causes of neurologic deficits after scuba diving is emphasized.[Nelson

Elaine E Nelson

1995-01-01

365

Peripartum acute aortic dissection: A case report & review of literature  

PubMed Central

Acute aortic dissection is a rare clinical entity that mainly affects patients older than 50 years. It is unusual in younger patients and its presence has been traditionally associated with trauma, Marfan syndrome, bicuspid aortic valve and pregnancy. We present here, a case of a 30 year old pregnant female with acute aortic dissection type A (De Bakey II), without family history of connective tissue diseases and signs of Marfan syndrome.

Aziz, Fahad; Penupolu, Sudheer; Alok, Anshu; Doddi, Sujatha; Abed, Mary

2011-01-01

366

The Effects of Interactive Dissection Simulation on the Performance and Achievement of High School Biology Students.  

ERIC Educational Resources Information Center

|A study of 61 high school biology students found that Interactive Video Disk (IVD) simulation was as effective as actual frog dissection in promoting student learning of frog anatomy and dissection procedures. When used as a preparation for dissection, IVD simulation helped students perform better dissections and learn more from doing…

Kinzie, Mable B.; And Others

1993-01-01

367

Electrothermal bipolar vessel sealing system in axillary dissection: A prospective randomized clinical study  

Microsoft Academic Search

We assessed whether axillary dissection using the electrothermal bipolar vessel sealing system (LigaSure™) improved perioperative outcome when compared with conventional axillary dissection, in a prospective randomized study of 100 women with breast cancer. Those needing axillary dissection were randomized to the use of LigaSure™ or to conventional axillary dissection (with 50 patients in each group, all of whom had a

Tomás Cortadellas; Octavi Córdoba; Martín Espinosa-Bravo; César Mendoza-Santin; Julia Rodríguez-Fernández; Antonio Esgueva; María Álvarez-Vinuesa; Isabel T. Rubio; Jordi Xercavins

368

VIRTUAL FETAL PIG DISSECTION AS AN AGENT OF KNOWLEDGE ACQUISITION FOR FEMALE HIGH SCHOOL BIOLOGY STUDENTS  

Microsoft Academic Search

This study attempted to determine if a virtual fetal pig dissection can be used as a viable alternative for an actual dissection for females enrolled in high school biology classes by comparing the knowledge acquisition between the experimental (virtual dissection) and control (actual dissection) groups. Two hundred and twenty four students enrolled in biology classes in a suburban all-girl parochial

Rebecca S. Maloney

369

Tyrosine-Phosphoproteome Dynamics  

Microsoft Academic Search

\\u000a Signal transduction systems are known to widely regulate complex biological events such as cell proliferation, differentiation,\\u000a and apoptosis. Since numerous biological analyses have revealed phosphotyrosine-dependent networks play a key role in transmitting\\u000a signals, a comprehensive and fine description of their dynamic behavior would contribute substantially toward system-level\\u000a understanding of the regulatory mechanisms that result in each biological effect. Recent technological

Masaaki Oyama; Shinya Tasaki; Hiroko Kozuka-Hata

370

FBN1 mutations in patients with descending thoracic aortic dissections.  

PubMed

Aortic aneurysm and dissection cause significant morbidity and mortality. There are several known single gene disorders that predispose to isolated aortic disease and eventually aneurysm and dissection. FBN1 mutations are associated with multiple clinical phenotypes, including Marfan syndrome (MFS), MASS phenotype, and familial ectopia lentis, but rarely with isolated aortic aneurysm and dissection. In this report, we describe three patients who presented with primary descending thoracic aortic dissection and who were found to have an FBN1 mutation. None of the patients fulfilled clinical criteria for the diagnosis of MFS, and all had few or none of the skeletal features typical of the condition. Two patients had a history of long-term hypertension, and such a history was suspected in the third patient. These observations suggest that some individuals with FBN1 mutations have significant aortic disease involvement of other systems that is typical of FBN1 mutation-related syndromes. Superimposed risk factors, such as hypertension, may weaken the aortic wall and eventually lead to aortic dissection. Given that the cost continues to decrease, we suggest that diagnostic DNA sequencing for FBN1 mutations in patients with thoracic aortic aneurysms and dissection may be a practical clinical step in evaluating such patients and at-risk family members. PMID:20082464

Brautbar, Ariel; LeMaire, Scott A; Franco, Luis M; Coselli, Joseph S; Milewicz, Dianna M; Belmont, John W

2010-02-01

371

Ruptured vertebral artery dissecting aneurysms treated with endovascular treatment.  

PubMed

Intracranial vertebral artery (VA) dissecting aneurysms often present with severe subarachnoid hemorrhage (SAH) and a subsequent high rate of mortality. We retrospectively studied the treatment efficacy and outcomes of 26 patients with ruptured VA dissecting aneurysms treated with endovascular surgery. Twenty-six patients with ruptured VA dissecting aneurysms were enrolled. Fifteen patients presented with poor-grade SAH and eleven with good-grade SAH. All patients were treated with endovascular treatment. We reviewed modes of therapy, complications and clinical outcomes. Coil occlusion of the artery at the dissecting aneurysm was performed in 24 patients. Proximal parent artery occlusion was performed in 2 patients. Obliteration of the dissecting aneurysm on postoperative angiogram was found in all patients. No patient sustained permanent complications associated with endovascular treatment. Regarding clinical outcome, although five patients died due to severe SAH, 19 patients had a good recovery or moderate disability. Ruptured VA dissecting aneurysms can be managed safely with coil occlusion of the lesion and/or parent artery. PMID:20027810

Shibukawa, Masaaki; Sakamoto, Shigeyuki; Kiura, Yoshihiro; Matsushige, Toshinori; Kurisu, Kaoru

2009-09-01

372

Outcome of extensive coronary artery dissection during coronary angioplasty.  

PubMed Central

A total of 32 (3.6%) patients of 880 undergoing coronary angioplasty during a nine year period at one hospital had extensive dissection (defined as a dissection extending beyond the limits of the dilated angioplasty balloon) in the coronary artery in which the angioplasty procedure was performed. Two (6.25%) of the 32 patients (both of whom were undergoing angioplasty because of unstable angina that was refractory to medical treatment) died as a consequence of the coronary artery dissection. Twelve (38%) needed immediate coronary artery bypass surgery and 11 (34%) had a myocardial infarction, which in four was minor in extent. During follow up, 20 of the 32 patients were successfully managed by medical treatment; only two needed further angioplasty procedures. There were no late deaths. Extensive coronary artery dissection is a serious complication of coronary angioplasty, with a high early mortality and a high incidence of infarction and requirement for bypass surgery. None the less, patients with extensive dissection who are free from the manifestations of acute ischaemia at the end of the procedure can be managed conservatively and have a good immediate and medium term outlook. Attempts should be made to stabilise extensive dissection during coronary angioplasty so that surgical intervention can be delayed or avoided altogether if possible. Images

Cripps, T R; Morgan, J M; Rickards, A F

1991-01-01

373

"Curettage and aspiration dissection technique" using PMOD for liver resection  

PubMed Central

Background and aims. To introduce a special dissection technique named “Curettage and Aspiration Dissection Technique” (CADT) using a versatile instrument called Peng's Multifunction Operative Dissector (PMOD) for liver resection. PMOD is an electrosurgical pencil with an inline suction, bearing four functions: electric cutting, coagulation, aspiration and dissection, The above-mentioned functions can be achieved simultaneously or sequentially during liver resection. The purpose of this study was to evaluate this technique and the special electrosurgical device in hepatic surgery. Patients and methods. From June 2005 to December 2006, 70 consecutive patients with segmentectomy or major hepatectomy were performed with this dissection technique by the same surgeon. Peri-operative data and the technical aspect of this device and dissection technique for various types of liver resection were summarised. Results. Forty-nine of 70 cases with various degrees of cirrhosis. Median blood loss were 470 ml (100–2400 ml), the bleeding and mortality within one month postoperatively was zero. There were postoperative complications in 20 patients: bile leak occurred in five cases, nine cases with right pleural effusion and six with ascites. No relative complications with this method were found. Conclusion. The CADT and PMOD can achieve better dissection and hemostasis. It possible is a much more valuable alternative to other devices currently used for liver surgery.

Peng, S. Y.

2008-01-01

374

Unraveling pancreatic islet biology by quantitative proteomics  

SciTech Connect

The pancreatic islets of Langerhans play a critical role in maintaining blood glucose homeostasis by secreting insulin and several other important peptide hormones. Impaired insulin secretion due to islet dysfunction is linked to the pathogenesis underlying both Type 1 and Type 2 diabetes. Over the past 5 years, emerging proteomic technologies have been applied to dissect the signaling pathways that regulate islet functions and gain an understanding of the mechanisms of islet dysfunction relevant to diabetes. Herein, we briefly review some of the recent quantitative proteomic studies involving pancreatic islets geared towards gaining a better understanding of islet biology relevant to metabolic diseases.

Zhou, Jianying; Dann, Geoffrey P.; Liew, Chong W.; Smith, Richard D.; Kulkarni, Rohit N.; Qian, Weijun

2011-08-01

375

Coronary artery dissection with rupture of aortic valve commissure following type A aortic dissection: the role of 64-slice MDCT.  

PubMed

A rare case of bilateral coronary artery dissection with rupture of aortic valve commissure following type A aortic dissection is described. 64-slice multidetector computed tomography (MDCT) was able to demonstrate both this findings along with involvement of other neck vessels. TEE demonstrated the severity and mechanisms of aortic valve damage and assisted the surgeon in valve repair. MDCT has played an invaluable role in the diagnosis of the abnormal details of such life-threatening vascular complications. PMID:18384568

Das, K M; Abdou, Sayed M; El-Menyar, Ayman; Ayman, El Menyar; Khulaifi, A A; Nabti, A L

2008-03-31

376

A Second-Generation Device for Automated Training and Quantitative Behavior Analyses of Molecularly-Tractable Model Organisms  

Microsoft Academic Search

A deep understanding of cognitive processes requires functional, quantitative analyses of the steps leading from genetics and the development of nervous system structure to behavior. Molecularly-tractable model systems such as Xenopus laevis and planaria offer an unprecedented opportunity to dissect the mechanisms determining the complex structure of the brain and CNS. A standardized platform that facilitated quantitative analysis of behavior

Douglas Blackiston; Tal Shomrat; Cindy L. Nicolas; Christopher Granata; Michael Levin

2010-01-01

377

Spontaneous vertebral dissection: Clinical, conventional angiographic, CT, and MR findings  

SciTech Connect

The purpose of this study was to determine if typical clinical and neuroradiologic patterns exist in patients with spontaneous vertebral artery (VA) dissection. The medical records and neuroradiologic examinations of 14 patients with spontaneous VA dissection were reviewed. The medical records were examined to exclude patients with a history of trauma and to record evidence of a nontratimatic precipitating event ({open_quotes}trivial trauma{close_quotes}) and presence of possible risk factors such as hypertension. All patients under-went conventional angiography, 13 either CT or MRI (II both CT and MRI), and 3 MRA. Conventional arteriograrris were evaluated for dissection site, evidence of fibromuscular dysplasia, luminal stenosis or occlusion, and pseudoaneurysm formation, CT examinations for the presence of infarction or subarachnoid hemorrhage, MR examinations for the presence of infarction or arterial signal abnormality, and MR angiograms for abnormality of the arterial signal column. Seven patients had precipitating events within 24 h of onset of symptoms that may have been causative of dissection and five had hypertension. At catheter angiography, two patients had dissections in two arteries (both VAs in one patient, VA and internal carotid artery in one patient), giving a total of 15 VAs with dissection. Dissection sites included V1 in four patients, V2 in one patient, V3 in three patients, V4 in six patients, and both V3 and V4 in one patient. Luminal stenosis was present in 13 VAs, occlusion in 2, pseudoaneurysm in 1, and evidence of fibromuscular dysplasia in 1. Posterior circulation infarcts were found on CT or MR in five patients. Subarachnoid hemorrhage was found on CT in two patients and by lumbar puncture alone in two patients. Abnormal periarterial signal on MRI was seen in three patients. MRA demonstrated absent VA signal in one patient, pseudoaneurysm in one, and a false-negative examination in one.

Provenzale, J.M.; Morgenlander, J.C. [Duke Univ. Medical Center, Durham, NC (United States); Gress, D. [Univ. of California, San Francisco, CA (United States)

1996-03-01

378

A comparison of retention of anatomical knowledge in an introductory college biology course: Traditional dissection vs. virtual dissection  

NASA Astrophysics Data System (ADS)

Dissection has always played a crucial role in biology and anatomy courses at all levels of education. However, in recent years, ethical concerns, as well as improved technology, have brought to the forefront the issue of whether virtual dissection is as effective or whether it is more effective than traditional dissection. Most prior research indicated the two methods produced equal results. However, none of those studies examined retention of information past the initial test of knowledge. Two groups of college students currently enrolled in an introductory level college biology course were given one hour to complete a frog dissection. One group performed a traditional frog dissection, making cuts in an actual preserved frog specimen with scalpels and scissors. The other group performed a virtual frog dissection, using "The Digital Frog 2" software. Immediately after the dissections were completed, each group was given an examination consisting of questions on actual specimens, pictures generated from the computer software, and illustrations that neither group had seen. Two weeks later, unannounced, the groups took the same exam in order to test retention. The traditional dissection group scored significantly higher on two of the three sections, as well as the total score on the initial exam. However, with the exception of specimen questions (on which the traditional group retained significantly more information), there was no significant difference in the retention from exam 1 to exam 2 between the two groups. These results, along with the majority of prior studies, show that the two methods produce, for the most part, the same end results. Therefore, the decision of which method to employ should be based on the goals and preferences of the instructor(s) and the department. If that department's goals include: Being at the forefront of new technology, increasing time management, increasing student: teacher ratio for economic reasons, and/or ethical issues, then the choice should be the use of computer software. If the goals include: Students gaining a 3-dimensional feel for the location and relationship of parts to one another, students being able to see various naturally occurring anomalies, and increased experience with manipulation of dissection tools, then the choice should be dissection of actual specimens. It is important to note, however, that regardless of which method is chosen, the effectiveness of that method is very much dependent on the skill and enthusiasm of the instructor.

Taeger, Kelli Rae

379

Quantitative Literacy  

NSDL National Science Digital Library

This resource guide from the Middle School Portal 2 project, written specifically for teachers, provides links to exemplary resources including background information, lessons, career information, and related national science education standards.On this wiki page, you will find online lessons, activities, and projects that allow students a range of real-world contexts. The Content Collections section contains sites that offer sets of problems and illustrations that connect middle school math to down-to-earth settings. The Interdisciplinary Lessons and Activities section offers activities and projects ready for interdisciplinary teaching. Each of the following sections focuses on a math topic: Data Analysis and Display, Probability, Measurement, Number and Operations. The resources offer mathematics in settings that deliberately cross over into other areas of the curriculum. Finally, for teachers looking for support in teaching quantitative literacy, a new approach for us all, Background Information for Teachers presents a select set of professional resources.

Herrera, Terese

2009-04-01

380

An integrated comparative phosphoproteomic and bioinformatic approach reveals a novel class of MPM-2 motifs upregulated in EGFRvIII-expressing glioblastoma cells†  

PubMed Central

Glioblastoma (GBM, WHO grade IV) is an aggressively proliferative and invasive brain tumor that carries a poor clinical prognosis with a median survival of 9 to 12 months. In a prior phosphoproteomic study performed in the U87MG glioblastoma cell line, we identified tyrosine phosphorylation events that are regulated as a result of titrating EGFRvIII, a constitutively active mutant of the epidermal growth factor receptor (EGFR) associated with poor prognosis in GBM patients. In the present study, we have used the phosphoserine/phosphothreonine-specific antibody MPM-2 (mitotic protein monoclonal #2) to quantify serine/threonine phosphorylation events in the same cell lines. By employing a bioinformatic tool to identify amino acid sequence motifs regulated in response to increasing oncogene levels, a set of previously undescribed MPM-2 epitope sequence motifs orthogonal to the canonical “pS/pT-P” motif was identified. These motifs contain acidic amino acids in combinations of the ?5, ?2, +1, +3, and +5 positions relative to the phosphorylated amino acid. Phosphopeptides containing these motifs are upregulated in cells expressing EGFRvIII, raising the possibility of a general role for a previously unrecognized acidophilic kinase (e.g. casein kinase II (CK2)) in cell proliferation downstream of EGFR signaling.

Joughin, Brian A.; Naegle, Kristen M.; Huang, Paul H.; Yaffe, Michael B.

2009-01-01

381

Phosphoproteomic Analysis Reveals the Effects of PilF Phosphorylation on Type IV Pilus and Biofilm Formation in Thermus thermophilus HB27.  

PubMed

Thermus thermophilus HB27 is an extremely thermophilic eubacteria with a high frequency of natural competence. This organism is therefore often used as a thermophilic model to investigate the molecular basis of type IV pili-mediated functions, such as the uptake of free DNA, adhesion, twitching motility, and biofilm formation, in hot environments. In this study, the phosphoproteome of T. thermophilus HB27 was analyzed via a shotgun approach and high-accuracy mass spectrometry. Ninety-three unique phosphopeptides, including 67 in vivo phosphorylated sites on 53 phosphoproteins, were identified. The distribution of Ser/Thr/Tyr phosphorylation sites was 57%/36%/7%. The phosphoproteins were mostly involved in central metabolic pathways and protein/cell envelope biosynthesis. According to this analysis, the ATPase motor PilF, a type IV pili-related component, was first found to be phosphorylated on Thr-368 and Ser-372. Through the point mutation of PilF, mimic phosphorylated mutants T368D and S372E resulted in nonpiliated and nontwitching phenotypes, whereas nonphosphorylated mutants T368V and S372A displayed piliation and twitching motility. In addition, mimic phosphorylated mutants showed elevated biofilm-forming abilities with a higher initial attachment rate, caused by increasing exopolysaccharide production. In summary, the phosphorylation of PilF might regulate the pili and biofilm formation associated with exopolysaccharide production. PMID:23828892

Wu, Wan-Ling; Liao, Jiahn-Haur; Lin, Guang-Huey; Lin, Miao-Hsia; Chang, Ying-Che; Liang, Suh-Yuen; Yang, Feng-Ling; Khoo, Kay-Hooi; Wu, Shih-Hsiung

2013-07-04

382

Dissecting the Impact of Matrix Anchorage and Elasticity in Cell Adhesion  

PubMed Central

Abstract Extracellular matrices determine cellular fate decisions through the regulation of intracellular force and stress. Previous studies suggest that matrix stiffness and ligand anchorage cause distinct signaling effects. We show herein how defined noncovalent anchorage of adhesion ligands to elastic substrates allows for dissection of intracellular adhesion signaling pathways related to matrix stiffness and receptor forces. Quantitative analysis of the mechanical balance in cell adhesion using traction force microscopy revealed distinct scalings of the strain energy imparted by the cells on the substrates dependent either on matrix stiffness or on receptor force. Those scalings suggested the applicability of a linear elastic theoretical framework for the description of cell adhesion in a certain parameter range, which is cell-type-dependent. Besides the deconvolution of biophysical adhesion signaling, site-specific phosphorylation of focal adhesion kinase, dependent either on matrix stiffness or on receptor force, also demonstrated the dissection of biochemical signaling events in our approach. Moreover, the net contractile moment of the adherent cells and their strain energy exerted on the elastic substrate was found to be a robust measure of cell adhesion with a unifying power-law scaling exponent of 1.5 independent of matrix stiffness.

Pompe, Tilo; Glorius, Stefan; Bischoff, Thomas; Uhlmann, Ina; Kaufmann, Martin; Brenner, Sebastian; Werner, Carsten

2009-01-01

383

Eight-year experience of intraoperative aortic dissection.  

PubMed

Aortic dissection is a rare but devastating complication of cardiac operations. The purpose of this investigation was to assess the occurrence of aortic dissection during elective cardiac operations and the usefulness of intraoperative transesophageal echocardiography for the diagnosis and management of this complication. Data of consecutive adult patients undergoing elective cardiac surgery with transesophageal echocardiographic monitoring during an 8-year period were studied retrospectively. Aortic dissection was identified in 7 (0.13%) of 5,247 patients, and diagnosed immediately by transesophageal echocardiography in 5 of them; 2 were diagnosed later by transesophageal echocardiography. All aortic dissections were type A and they occurred after completion of the primary procedure. Two patients treated conservatively died within 5 days. Four of the 5 patients who underwent immediate reoperation survived with serious postoperative complications. Transesophageal echocardiography should be carried out when there is a risk of aortic dissection during cardiac operations, especially in the posterior wall of the ascending aorta, to avoid missing the diagnosis and delaying treatment. PMID:19713339

Lin, Tzu-Yu; Chen, Yih-Sharng; Chiu, Kuan-Ming; Hsu, Ron-Bin; Yu, Hsi-Yu; Wang, Ming-Jiuh

2009-08-01

384

Congenital pericardial defect with ruptured acute type A aortic dissection.  

PubMed

We report 2 cases of congenital pericardial defect with ruptured acute type A aortic dissection. Case 1: An 83-year old man presented with sudden chest and back pain, and computed tomography (CT) showed acute aortic dissection with left pleural massive effusion. Because of his unstable haemodynamic condition with low blood pressure, an emergency operation was performed. We observed small amounts of bloody pericardial effusion, massive left-sided bloody pleural effusion and a partial left-sided pericardial defect of the pulmonary artery. The ascending aorta was replaced. The postoperative course was uneventful. Case 2: A 79-year old man presented with fainting followed by cardiac arrest and was resuscitated. Chest CT showed acute aortic dissection and massive haemothorax. Emergency operation was attempted, but was given up. We observed partial left-sided pericardial defect of the pulmonary artery. Further, we reviewed 6 cases of congenital pericardial defect with ruptured acute aortic dissection, including our 2 cases. In all the cases, the patients did not develop cardiac tamponade but had massive haemothorax due to congenital pericardial defects leading to confusion in diagnoses and surgical strategies. Therefore, it may be necessary to consider congenital pericardial defects before performing an operation in case of acute type A aortic dissection with massive haemothorax. PMID:22843655

Furui, Masato; Ohashi, Takeki; Hirai, Yasutaka; Kageyama, Soichirou

2012-07-27

385

Is there a relationship between weather conditions and aortic dissection?  

PubMed Central

Background Bleeding and rupture of blood vessels has been correlated with weather conditions in the past. This is the first study in the world literature with the aim of investigating the relationship between atmospheric pressure and temperature with the presentation of aortic dissection. Methods The dates of all emergency aortic dissection repairs from 1996–2002 in a regional cardiothoracic unit at Blackpool Victoria Hospital were obtained. Hourly temperature and pressure data from a regional weather station for this time period was supplied by the Meteorological Office. The mean and standard deviation of hourly temperature and pressure data for that month were compared to the mean and standard deviation of the data 24 and 48 hours prior to the aortic dissection. Results 26 patients were found to have been operated on during the time period studied. There was no statistically significant correlation between temperature or atmospheric pressure readings, and the incidence of aortic dissection, using a Bonferonni-corrected significance p-value of 0.005 Conclusion This study is the first to examine the relationship between atmospheric pressure, temperature and dissecting thoracic aorta. No statistically significant relationship was demonstrable.

Repanos, Costa; Chadha, Neil K

2005-01-01

386

Genetic dissection of maize phenology using an intraspecific introgression library  

PubMed Central

Background Collections of nearly isogenic lines where each line carries a delimited portion of a donor source genome into a common recipient genetic background are known as introgression libraries and have already shown to be instrumental for the dissection of quantitative traits. By means of marker-assisted backcrossing, we have produced an introgression library using the extremely early-flowering maize (Zea mays L.) variety Gaspé Flint and the elite line B73 as donor and recipient genotypes, respectively, and utilized this collection to investigate the genetic basis of flowering time and related traits of adaptive and agronomic importance in maize. Results The collection includes 75 lines with an average Gaspé Flint introgression length of 43.1 cM. The collection was evaluated for flowering time, internode length, number of ears, number of nodes (phytomeres), number of nodes above the ear, number and proportion of nodes below the ear and plant height. Five QTLs for flowering time were mapped, all corresponding to major QTLs for number of nodes. Three additional QTLs for number of nodes were mapped. Besides flowering time, the QTLs for number of nodes drove phenotypic variation for plant height and number of nodes below and above the top ear, but not for internode length. A number of apparently Mendelian-inherited phenotypes were also observed. Conclusions While the inheritance of flowering time was dominated by the well-known QTL Vgt1, a number of other important flowering time QTLs were identified and, thanks to the type of plant material here utilized, immediately isogenized and made available for fine mapping. At each flowering time QTL, early flowering correlated with fewer vegetative phytomeres, indicating the latter as a key developmental strategy to adapt the maize crop from the original tropical environment to the northern border of the temperate zone (southern Canada), where Gaspé Flint was originally cultivated. Because of the trait differences between the two parental genotypes, this collection will serve as a permanent source of nearly isogenic materials for multiple studies of QTL analysis and cloning.

2011-01-01

387

Dissecting sources of quantitative gene expression pattern divergence between Drosophila species.  

PubMed

Gene expression patterns can diverge between species due to changes in a gene's regulatory DNA or changes in the proteins, e.g., transcription factors (TFs), that regulate the gene. We developed a modeling framework to uncover the sources of expression differences in blastoderm embryos of three Drosophila species, focusing on the regulatory circuit controlling expression of the hunchback (hb) posterior stripe. Using this framework and cellular-resolution expression measurements of hb and its regulating TFs, we found that changes in the expression patterns of hb's TFs account for much of the expression divergence. We confirmed our predictions using transgenic D. melanogaster lines, which demonstrate that this set of orthologous cis-regulatory elements (CREs) direct similar, but not identical, expression patterns. We related expression pattern differences to sequence changes in the CRE using a calculation of the CRE's TF binding site content. By applying this calculation in both the transgenic and endogenous contexts, we found that changes in binding site content affect sensitivity to regulating TFs and that compensatory evolution may occur in circuit components other than the CRE. PMID:22893002

Wunderlich, Zeba; Bragdon, Meghan D; Eckenrode, Kelly B; Lydiard-Martin, Tara; Pearl-Waserman, Sivanne; DePace, Angela H

2012-01-01

388

Recurrent aortic dissection in Marfan's syndrome: possible effects of anticoagulation.  

PubMed

Recent reports support the role of a valve-sparing procedure in ascending aortic dissection in patients with Marfans syndrome. A 49-year-old woman with Marfans syndrome and prior aortic aneurysm repaired with a composite graft presented with sudden-onset chest pain. Following an initial negative computed tomographic (CT) scan, a long dissection involving the descending thoracic and abdominal aorta was discovered on a repeat CT scan a few hours later. Symptoms improved gradually with optimal medical management and the patient was discharged home on anticoagulant therapy. Although no direct cause-and-effect relationship can be established, chronic anticoagulant therapy may accelerate the progression of recurrent dissection in these patients. A valve-sparing procedure should be considered in eligible patients with Marfans syndrome who need operative correction to avoid possible future untoward effects of long-term anticoagulant therapy. PMID:12852802

Kantelhardt, Sven R; Pasnoori, Venkat; Varma, Jai; Rezazadeh, Arash; Dawn, Buddhadeb

389

Dissection of the atrial wall after mitral valve replacement.  

PubMed Central

We describe an unusual sequela of mitral valve replacement in a 50-year-old woman who had undergone a closed mitral commissurotomy in 1975. She was admitted to our hospital because of mitral restenosis in November 1993, at which time her mitral valve was replaced with a mechanical prosthesis. On the 8th postoperative day, the patient developed symptoms of heart failure; transesophageal echocardiography revealed dissection and rupture of the left atrial wall. At prompt reoperation, we found an interlayer dissection and rupture of the atrial wall into the left atrium. We repaired the ruptured atrial wall with a prosthetic patch. The postoperative course was uneventful, and postoperative transesophageal echocardiography showed normal prosthetic valve function and no dissection. Images

Lukacs, L; Kassai, I; Lengyel, M

1996-01-01

390

Radioguided neck dissection in recurrent metastatic papillary thyroid carcinoma.  

PubMed

Although radioguided surgery has been used for the excision of sentinel nodes in breast cancer and melanoma, sparse literature exists describing its use in thyroid cancer. We report a 69-year-old patient with a previous total thyroidectomy and lymph node dissection for papillary carcinoma who was subsequently found to have recurrent metastatic disease. After a therapeutic dose of radioactive iodine, a hand-held gamma-probe was used to selectively dissect the neck. The patient was offered radioguided revision neck dissection to remove the disease using residual radioactivity of the original therapeutic iodine 131 dose. Our case report seeks to demonstrate a recent example of our use of the gamma-probe in radioguided surgical excision of recurrent metastatic papillary thyroid carcinoma. PMID:16360827

Scurry, W Cooper; Lamarre, Eric; Stack, Brendan

391

Extracranial vertebral artery dissection causing cervical root lesion.  

PubMed

The authors report an unusual manifestation of extracranial vertebral artery dissection (VAD), presenting with a predominantly motor radicular manifestation. Cervical magnetic resonance imaging (MRI) revealed the intramural hematoma in the dissected vessel wall, compressing mainly the segmental motor root and, to a lesser degree, the sensory ganglion. In the digital subtraction angiography (DSA), a circumscribed narrowing of the incriminated vessel was demonstrated. Color-coded Duplex imaging (CDDI) revealed complete recanalization after a few days of anticoagulation treatment. Complete neurologic recovery was seen after 3 months. Considering the MRI data, the likely pathogenetic mechanism was compression of the nerve root by the intramural hematoma. The synopsis with similar cases in the literature points to the characteristic features, i.e., the association of neck pain with radicular motor deficit and the absence of degenerative disk disease. The respective syndrome should raise the suspicion of vertebral artery dissection, especially in young individuals. PMID:10800269

Fournier, J Y; Amsler, U; Weder, B; Heilbronner, R; Hildebrandt, G

2000-04-01

392

Advanced, recurrent mesothelioma growth mimicking an aortic dissection  

PubMed Central

In the emergency setting, a cold, clammy, dyspnoeic patient presenting with interscapular chest pain and unequal blood pressures suggests an acute aortic dissection until proven otherwise. By means of a case report, the authors detail one such patient who presented identically to one having an acute aortic dissection. Initial assessment showed unequal blood pressures in left and right arms, a resting tachycardia and indistinct heart sounds. Fluid resuscitation failed to improve the patient's physiological parameters and they rapidly deteriorated. The medical history included mesothelioma and atrial fibrillation. Existing investigations were reviewed and after thorough consideration of the patient's premorbid state and likely prognosis, the decision was made to palliate. The patient died shortly after being transferred to the oncology ward. Imaging is therefore integral to the assessment and management of a patient in whom an aortic dissection is feared.

Pankhania, Miran; Hardiment, Kate; Marathe, Mandar

2011-01-01

393

Digital dissection system for medical school anatomy training  

NASA Astrophysics Data System (ADS)

As technology advances, new and innovative ways of viewing and visualizing the human body are developed. Medicine has benefited greatly from imaging modalities that provide ways for us to visualize anatomy that cannot be seen without invasive procedures. As long as medical procedures include invasive operations, students of anatomy will benefit from the cadaveric dissection experience. Teaching proper technique for dissection of human cadavers is a challenging task for anatomy educators. Traditional methods, which have not changed significantly for centuries, include the use of textbooks and pictures to show students what a particular dissection specimen should look like. The ability to properly carry out such highly visual and interactive procedures is significantly constrained by these methods. The student receives a single view and has no idea how the procedure was carried out. The Department of Anatomy at Mayo Medical School recently built a new, state-of-the-art teaching laboratory, including data ports and power sources above each dissection table. This feature allows students to access the Mayo intranet from a computer mounted on each table. The vision of the Department of Anatomy is to replace all paper-based resources in the laboratory (dissection manuals, anatomic atlases, etc.) with a more dynamic medium that will direct students in dissection and in learning human anatomy. Part of that vision includes the use of interactive 3-D visualization technology. The Biomedical Imaging Resource (BIR) at Mayo Clinic has developed, in collaboration with the Department of Anatomy, a system for the control and capture of high resolution digital photographic sequences which can be used to create 3-D interactive visualizations of specimen dissections. The primary components of the system include a Kodak DC290 digital camera, a motorized controller rig from Kaidan, a PC, and custom software to synchronize and control the components. For each dissection procedure, the images are captured automatically, and then processed to generate a Quicktime VR sequence, which permits users to view an object from multiple angles by rotating it on the screen. This provides 3-D visualizations of anatomy for students without the need for special '3-D glasses' that would be impractical to use in a laboratory setting. In addition, a digital video camera may be mounted on the rig for capturing video recordings of selected dissection procedures being carried out by expert anatomists for playback by the students. Anatomists from the Department of Anatomy at Mayo have captured several sets of dissection sequences and processed them into Quicktime VR sequences. The students are able to look at these specimens from multiple angles using this VR technology. In addition, the student may zoom in to obtain high-resolution close-up views of the specimen. They may interactively view the specimen at varying stages of dissection, providing a way to quickly and intuitively navigate through the layers of tissue. Electronic media has begun to impact all areas of education, but a 3-D interactive visualization of specimen dissections in the laboratory environment is a unique and powerful means of teaching anatomy. When fully implemented, anatomy education will be enhanced significantly by comparison to traditional methods.

Augustine, Kurt E.; Pawlina, Wojciech; Carmichael, Stephen W.; Korinek, Mark J.; Schroeder, Kathryn K.; Segovis, Colin M.; Robb, Richard A.

2003-05-01

394

Spontaneous Celiac Artery Dissection Case Report and Literature Review  

PubMed Central

Symptomatic spontaneous celiac artery dissection is a rare condition that is being detected more often with the use of advanced imaging techniques. There is no consensus as to whether surgical or endovascular treatment is more appropriate. We describe the case of a 41-year-old hypertensive woman who presented with the sudden onset of sharp, persistent, right-upper-quadrant abdominal and epigastric pain. Magnetic resonance angiography of the abdomen revealed celiac artery dissection, with a flap compressing the lumen approximately 17 mm from the artery's origin at the aorta. Because of the patient's persistent epigastric pain, endovascular celiac artery stent implantation was performed with the use of 2 overlapping balloon-expandable stents. Twelve months after the procedure, the patient remained asymptomatic, and the stents were patent. This case and others in the medical literature suggest that endovascular treatment can be feasible in symptomatic patients with isolated spontaneous celiac artery dissection.

Obon-Dent, Mauricio; Shabaneh, Bahaeddin; Dougherty, Kathryn G.; Strickman, Neil E.

2012-01-01

395

The birth and evolution of neuroscience through cadaveric dissection.  

PubMed

Although interest in the art of dissection and vivisection has waxed and waned throughout the ages, the past century has seen it accepted as commonplace in medical schools across the country. No other practice in medicine has contributed more to the understanding of neuroanatomy and the neurosciences as dissection of the human cadaver, the origins of which are widely documented to have been in Alexandrian Greece. This article chronicles the fascinating and often controversial use of dissection and vivisection in these fields through the ages, beginning with Herophilus of Alexandria, among the first systematic dissectors in the history of Western medicine. The authors comment on its role in the development of modern neurosurgery and conclude with remarks about use of this educational tool today in the United States. PMID:20657312

Moon, Karam; Filis, Andreas K; Cohen, Alan R

2010-09-01

396

A case of postpartum spontaneous coronary artery dissection.  

PubMed

Spontaneous coronary artery dissection is rare and usually affects younger women in the peripartum period. Here, we report an interesting case of a 34-year-old woman with spontaneous coronary artery dissection that occurred 1 month after childbirth. Emergency coronary angiography showed stenosis of the left anterior descending artery, but immediately afterwards, a new occlusion of the right coronary artery occurred. Intravascular ultrasound was used to image both right and left coronary arteries. The new occlusion of the right coronary artery was probably iatrogenic, but the left coronary artery occlusion was spontaneous. The patient underwent percutaneous coronary intervention in the right coronary artery because of her unstable hemodynamic condition. Revascularization of the left coronary artery was performed by bypass grafting. The patient was discharged on postoperative day 30. As the optimal treatment for spontaneous coronary artery dissection has not yet been established, treatments should be based on the patient's clinical presentation. PMID:23775233

Okamoto, Minoru; Tanaka, Mutsuo; Ishii, Masanobu; Honda, Tsuyoshi; Koga, Hidenobu; Miyao, Yuji; Fujimoto, Kazuteru; Murayama, Toshihiko

2013-06-18

397

Second Harmonic Generation, Sum Frequency Generation, and ?(3): Dissecting Environmental Interfaces with a Nonlinear Optical Swiss Army Knife  

NASA Astrophysics Data System (ADS)

This review discusses recent advances in the nonlinear optics of environmental interfaces. We discuss the quantitative aspects of the label-free approaches presented here and demonstrate that nonlinear optics has now assumed the role of a Swiss Army knife that can be used to dissect, with molecular detail, the fundamental and practical aspects of environmental interfaces and heterogeneous geochemical environments. In this work, nonlinear optical methods are applied to complex organic molecules, such as veterinary antibiotics, and to small inorganic anions and cations, such as nitrate and chromate, or cadmium, zinc, and manganese. The environmental implications of the thermodynamic, kinetic, spectroscopic, structural, and electrochemical data are discussed.

Geiger, Franz M.

2009-05-01

398

Genetic dissection of a model complex trait using the Drosophila Synthetic Population Resource  

PubMed Central

Genetic dissection of complex, polygenic trait variation is a key goal of medical and evolutionary genetics. Attempts to identify genetic variants underlying complex traits have been plagued by low mapping resolution in traditional linkage studies, and an inability to identify variants that cumulatively explain the bulk of standing genetic variation in genome-wide association studies (GWAS). Thus, much of the heritability remains unexplained for most complex traits. Here we describe a novel, freely available resource for the Drosophila community consisting of two sets of recombinant inbred lines (RILs), each derived from an advanced generation cross between a different set of eight highly inbred, completely resequenced founders. The Drosophila Synthetic Population Resource (DSPR) has been designed to combine the high mapping resolution offered by multiple generations of recombination, with the high statistical power afforded by a linkage-based design. Here, we detail the properties of the mapping panel of >1600 genotyped RILs, and provide an empirical demonstration of the utility of the approach by genetically dissecting alcohol dehydrogenase (ADH) enzyme activity. We confirm that a large fraction of the variation in this classic quantitative trait is due to allelic variation at the Adh locus, and additionally identify several previously unknown modest-effect trans-acting QTL (quantitative trait loci). Using a unique property of multiparental linkage mapping designs, for each QTL we highlight a relatively small set of candidate causative variants for follow-up work. The DSPR represents an important step toward the ultimate goal of a complete understanding of the genetics of complex traits in the Drosophila model system.

King, Elizabeth G.; Merkes, Chris M.; McNeil, Casey L.; Hoofer, Steven R.; Sen, Saunak; Broman, Karl W.; Long, Anthony D.; Macdonald, Stuart J.

2012-01-01

399

Genetic dissection of NK cell responses  

PubMed Central

The association of Natural Killer (NK) cell deficiencies with disease susceptibility has established a central role for NK cells in host defence. In this context, genetic approaches have been pivotal in elucidating and characterizing the molecular mechanisms underlying NK cell function. To this end, homozygosity mapping and linkage analysis in humans have identified mutations that impact NK cell function and cause life-threatening diseases. However, several critical restrictions accompany genetic studies in humans. Studying NK cell pathophysiology in a mouse model has therefore proven a useful tool. The relevance of the mouse model is underscored by the similarities that exist between cell-structure-sensing receptors and the downstream signaling that leads to NK cell activation. In this review, we provide an overview of how human and mouse quantitative trait locis (QTLs) have facilitated the identification of genes that modulate NK cell development, recognition, and killing of target cells.

Moussa, Peter; Marton, Jennifer; Vidal, Silvia M.; Fodil-Cornu, Nassima

2012-01-01

400

Type B aortic dissection after the use of tadalafil.  

PubMed

A 63-year-old male patient with a type B aortic dissection after the use of tadalafil, a phosphodiesterase type 5 inhibitor, is presented. The possible role of a novel predisposing factor--sexual activity combined with tadalafil--is reviewed. This report and three other cases add a new dimension to the known predisposing factors such as chronic systemic hypertension, hereditary connective tissue diseases- and congenital aortic valve diseases. However, the precise role of phosphodiesterase type 5 inhibitors in the pathophysiology of aortic dissection remains unknown. PMID:22269733

Lameijer, Charlotte M; Tielliu, Ignace F J; van Driel, Mels F; Zeebregts, Clark J

2012-02-01

401

Pneumococcal Meningitis, Cerebral Venous Thrombosis, and Cervical Arterial Dissection  

PubMed Central

Background: Pneumococcal meningitis in adults is widely associated with intracranial complications, which occur in up to 74.7% of the patients. Method: Case report. Results: We report the case of a 40-year-old white female with pneumococcal meningitis after a sinus surgery, who developed a concomitant cerebral venous thrombosis and multiple cervical artery dissections. Following treatment with antibiotics and intravenous heparin, she had complete neurological recovery. Conclusions: Vascular complications should always be remembered and adequately treated in patients with bacterial meningitis. Cervical arterial dissections should be investigated as potential embolic sources of intracranial ischemic lesions.

Panicio, Mauricio Isaac; Foresto, Renato Demarchi; Mateus, Lucas; Monzillo, Paulo Helio; Alves, Monique Bueno; Silva, Gisele Sampaio

2013-01-01

402

Left main dissection and thrombosis in a young athlete.  

PubMed

Spontaneous coronary artery dissection is a rare but morbid event. We present the case of a previously healthy 38-year-old man who experienced severe chest discomfort while vigorously exercising. An acute anterolateral myocardial infarction was diagnosed. The patient underwent coronary angiography, demonstrating acute thrombosis of the left main coronary artery. The patient was referred for immediate bypass surgery. Examination of the left main coronary artery in the operating room revealed a dissection flap with thrombosis. With successful surgical intervention, the patient made an uneventful recovery. This case is discussed and the literature reviewed. PMID:16106188

Justice, L Todd; Dauterman, Kent; Smedira, Nicholas G; Moliterno, David J

403

Vertebral artery dissections afterchiropractic neck manipulationin Germany over three years  

Microsoft Academic Search

Vertebral artery dissection\\u000a (VAD) has been observed\\u000a in association with chirotherapy of\\u000a the neck. However, most publications\\u000a describe only single case reports\\u000a or a small number of cases.\\u000a We analyzed data from neurological\\u000a departments at university hospitals\\u000a in Germany over a three year\\u000a period of time of subjects with vertebral\\u000a artery dissections associated\\u000a with chiropractic neck manipulation.\\u000a We conducted a

U. Reuter; M. Hämling; I. Kavuk; K. M. Einhäupl; E. Schielke

2006-01-01

404

Quantitative Trait Loci Underlying Gene Product Variation: A Novel Perspective for Analyzing Regulation of Genome Expression  

Microsoft Academic Search

A methodology to dissect the genetic architecture of quantitative variation of numerous gene products simultaneously is proposed. For each individual of a segregating progeny, proteins extracted from a given organ are separated using two-dimensional electrophoresis, and their amounts are estimated with a computer-assisted system for spot quantification. Provided a complete genetic map is available, statistical procedures allow determination of the

C. Damerval; A. Maurice; J. M. Josse; D. de Vienne

1994-01-01

405

Molecular genetic mapping of quantitative trait loci associated with loaf volume in hexaploid wheat ( Triticum aestivum)  

Microsoft Academic Search

Major efforts in wheat research are being made to improve the yield and quality of wheat. Loaf volume (Lv) is the main quality parameter deciding the bread making potential of wheat. To genetically dissect quantitative trait loci (QTLs) for Lv, a Recombinant Inbred Line (RIL) population (F8) was developed from a cross between two Indian wheat varieties “HI 977” and

M. Elangovan; R. Rai; B. B. Dholakia; M. D. Lagu; R. Tiwari; R. K. Gupta; V. S. Rao; M. S. Röder; V. S. Gupta

2008-01-01

406

Angiographic findings in arteriovenous dissection (sheathotomy) for decompression of branch retinal vein occlusion  

Microsoft Academic Search

Background: Arteriove- nous dissection (sheathotomy) is a new therapeutic option in patients with branch retinal vein occlusion (BRVO) and macular involvement. We present an angiographic follow-up of 22 patients who underwent arte- riovenous dissection (AVD).

Thomas Kube; Nicolas Feltgen; Mona Pache; Julia Herrmann; Lutz Lothar Hansen

2005-01-01

407

A Novel Approach to the Dissection of the Human Knee  

ERIC Educational Resources Information Center

The knee is one of the most frequently injured joints of the human body with injuries affecting the general population and the athletic population of many age groups. Dissection procedures for the knee joint typically do not allow unobstructed visualization of the anterior cruciate or posterior cruciate ligaments without sacrificing the collateral…

Clemente, F. Richard; Fabrizio, Philip A.; Shumaker, Michael

2009-01-01

408

Repair of acute descending aortic dissection complicated by visceral ischemia.  

PubMed

Visceral ischemia is a rare but lethal complication of type III aortic dissection. We report a Marfan patient with such a complication who had a complete resolution of profound visceral ischemia despite a delay in repair of over 48 hours. PMID:10510012

Wang, N; Wong, D T; Rivera, J L; Bansal, R C; Gundry, S R

1999-09-01

409

Tensor fasciae lata myocutaneous flap reconstruction following ilioinguinal node dissection  

Microsoft Academic Search

Ilioinguinal block dissections have been traditionally associated with a high incidence of complications. Wound complication rates are in the range of 50 to 70% and lymphedema is seen in a majority of cases. A variety of incisions and reconstructive techniques have been experimented with in an effort to reduce the morbidity. We have used the tensor fasciae lata (TFL) myocutaneous

D. N. Savant; A. V. Dalal; S. G. Patel; H. M. Bhathena; N. M. Kavarana

1996-01-01

410

Ultrastructural pathology of aortic dissections in patients with Marfan syndrome  

Microsoft Academic Search

Despite the discovery in 1990 that mutations in the fibrillin-1 gene cause the Marfan syndrome, the pathogenesis of the life-threatening dissections associated with this disease is far from elucidated. Both the massive number of known fibrillin-1 mutations that result in a heterogeneous patient population and the strongly heterogeneous histology of patients' aortae presumably contribute to this lack of knowledge. We

Koert P. Dingemans; Peter Teeling; Allard C. van der Wal; Anton E. Becker

2006-01-01

411

Technology Insight: endoscopic submucosal dissection of gastrointestinal neoplasms  

Microsoft Academic Search

Gastrointestinal neoplasms can be cured by local resection as long as the lesions are in the early stage and have not metastasized. Endoscopic resection is a minimally invasive treatment for early-stage gastrointestinal neoplasms, and endoscopic submucosal dissection (ESD) is one type of endoscopic resection that has been developed in the past 10 years. For ESD to be a reliable, curative

Hironori Yamamoto

2007-01-01

412

Radioguided neck dissection in recurrent metastatic papillary thyroid carcinoma  

Microsoft Academic Search

Although radioguided surgery has been used for the excision of sentinel nodes in breast cancer and melanoma, sparse literature exists describing its use in thyroid cancer. We report a 69-year-old patient with a previous total thyroidectomy and lymph node dissection for papillary carcinoma who was subsequently found to have recurrent metastatic disease. After a therapeutic dose of radioactive iodine, a

W. Cooper Scurry; Eric Lamarre; Brendan Stack

2006-01-01

413

Standard methods for Apis mellifera anatomy and dissection  

Technology Transfer Automated Retrieval System (TEKTRAN)

An understanding of the anatomy and functions of internal and external structures are fundamental to many studies on the honey bee Apis mellifera. Similarly, proficiency in dissection techniques is vital for many more complex procedures. In this paper, which is a prelude to the other papers of the C...

414

Mouse Models for the Genetic Dissection of Atopy  

Microsoft Academic Search

Atopic disorders are complex traits with a significant contribution of heritability. Several mouse models for atopic phenotypes such as allergen-induced and intrinsic asthma, atopic dermatitis and immediate cutaneous hypersensitivity have been used to systematically dissect the genetics of these diseases. Many of the chromosomal regions identified in genome-wide screens colocalize with linkage regions of autoimmune phenotypes suggesting common regulatory genes

Andrea Heinzmann; Angelika Daser

2002-01-01

415

Occult traumatic dissection of vertebral artery with an excellent outcome.  

PubMed

We present the case of a young male with severe head injury, cervico-thoracic fractures, and an initially unrecognized brainstem infarct due to unilateral dissection of vertebral artery, who made an unusually excellent recovery. This report stresses the importance of prompt clinico-imaging diagnosis and prophylactic anticoagulant treatment in such cases. PMID:15702842

Stranjalis, G; Papavlassopoulos, F; Kouyialis, A T; Korfias, S; Bontozoglou, N; Sakas, D E

2004-08-01

416

Fibromuscular Dysplasia May Herald Symptomatic Recurrence of Cervical Artery Dissection  

Microsoft Academic Search

Background: The prevalence of fibromuscular dysplasia (FMD) in patients with cervical artery dissection (CAD) is unknown. Our objectives were to assess the risk of CAD recurring as a stroke or a transient ischemic attack and the association of these events with FMD. Methods: We prospectively included and followed 103 consecutive patients who had been admitted for a CAD. The median

J. M. de Bray; G. Marc; V. Pautot; B. Vielle; A. Pasco; P. Lhoste; F. Dubas

2007-01-01

417

Repair of a vertebral artery dissection. Case report.  

PubMed

The case is presented of a 38-year-old woman who suffered multiple cerebellar infarctions as a result of emboli from a vertebral artery dissection. Surgical therapy led to a satisfactory recovery. This case emphasizes the importance of an aggressive approach to such lesions. PMID:3950750

Alexander, J J; Glagov, S; Zarins, C K

1986-04-01

418

Vertebral Artery Dissection in Children: A Comprehensive Review  

Microsoft Academic Search

Vertebral artery dissection (VAD) has been infrequently recognized in children. The authors have reviewed 68 reported cases of VAD in children in the existing literature. An association between routine types of neck movement in sports and the evolution of VAD was recognized in half of the reported cases. Boys outnumbered girls by a ratio of 6.6 to 1, in contrast

Izhar Hasan; Simon Wapnick; Michael S. Tenner; William T. Couldwell

2002-01-01

419

Using a Dissecting Microscope in Teaching Introductory Chemistry.  

ERIC Educational Resources Information Center

|To have students develop observational skills and acquire an excitement about chemistry, stereoscopic dissecting microscopes are used to observe the physical characteristics and chemical reactions of various substances. Several of these reactions (including dissolving potassium permanganate in deionized water and reactions between copper metal…

Winokur, Robert; Monroe, Manus

1985-01-01

420

Student Attitudes to Whole Body Donation are Influenced by Dissection  

NSDL National Science Digital Library

This article describes a pre-post survey given to medical students in a gross anatomy course addressing the attitudes toward becoming cadaver donators. Outcomes discuss the influence of actively dissecting a cadaver and how that shifts students away from donating one's body.

2008-09-01