Search Results - "WALTER, John A."

International NMR-Based Environmental Metabolomics Intercomparison Exercise by Viant, Mark R, Bearden, Daniel W, Bundy, Jacob G, Burton, Ian W, Collette, Timothy W, Ekman, Drew R, Ezernieks, Vilnis, Karakach, Tobias K, Lin, Ching Yu, Rochfort, Simone, Ropp, Jeffrey S. de, Teng, Quincy, Tjeerdema, Ronald S, Walter, John A, Wu, Huifeng

“…Several fundamental requirements must be met so that NMR-based metabolomics and the related technique of metabonomics can be formally adopted into…”
Get full text

The preparation of certified calibration solutions for azaspiracid-1, -2, and -3, potent marine biotoxins found in shellfish by Perez, Ruth A., Rehmann, Nils, Crain, Sheila, LeBlanc, Patricia, Craft, Cheryl, MacKinnon, Shawna, Reeves, Kelley, Burton, Ian W., Walter, John A., Hess, Philipp, Quilliam, Michael A., Melanson, Jeremy E.

“…The production and certification of a series of azaspiracid (AZA) calibration solution reference materials is described. Azaspiracids were isolated from…”
Get full text

Detection and Identification of Spirolides in Norwegian Shellfish and Plankton by Aasen, John, MacKinnon, Shawna L, LeBlanc, Patricia, Walter, John A, Hovgaard, Peter, Aune, Tore, Quilliam, Michael A

“…Mussels sampled in the spring of 2002 and 2003 from Skjer, a location in Sognefjord, Norway, tested positive in the mouse bioassay for lipophilic toxins. The…”
Get full text

Characterization of Spirolides A, C, and 13-Desmethyl C, New Marine Toxins Isolated from Toxic Plankton and Contaminated Shellfish by Hu, Tingmo, Burton, Ian W, Cembella, Allan D, Curtis, Jonathan M, Quilliam, Michael A, Walter, John A, Wright, Jeffrey L. C

“…Three additional marine toxins, spirolides A (1), C (3), and 13-desmethyl-C (7), were isolated from contaminated scallops and phytoplankton collections…”
Get full text

Sulfated diesters of okadaic acid and DTX-1: Self-protective precursors of diarrhetic shellfish poisoning (DSP) toxins by Hu, Tingmo, LeBlanc, Patricia, Burton, Ian W., Walter, John A., McCarron, Pearse, Melanson, Jeremy E., Strangman, Wendy K., Wright, Jeffrey L.C.

“…Many toxic secondary metabolites used for defense are also toxic to the producing organism. One important way to circumvent toxicity is to store the toxin as…”
Get full text

Analysis of time course 1H NMR metabolomics data by multivariate curve resolution by Karakach, Tobias K., Knight, Richard, Lenz, Eva M., Viant, Mark R., Walter, John A.

“…Modeling NMR‐based metabolomics data often involves linear methods such as principal component analysis (PCA) and partial least squares (PLS). These methods…”
Get full text

Isolation and Structure Elucidation of New and Unusual Saxitoxin Analogues from Mussels by Dell’Aversano, Carmela, Walter, John A, Burton, Ian W, Stirling, David J, Fattorusso, Ernesto, Quilliam, Michael A

“…Chemical analyses of plankton and highly toxic mussel samples collected in eastern Canada during an intense bloom of the dinoflagellate Alexandrium tamarense…”
Get full text

Characterization of the measurement error structure in 1D H NMR data for metabolomics studies by Karakach, Tobias K, Wentzell, Peter D, Walter, John A

“…NMR-based metabolomics is characterized by high throughput measurements of the signal intensities of complex mixtures of metabolites in biological samples by…”
Get full text

1H-NMR and mass spectrometric characterization of the metabolic response of juvenile Atlantic salmon (Salmo salar) to long-term handling stress by Karakach, Tobias K., Huenupi, Elizabeth C., Soo, Evelyn C., Walter, John A., Afonso, Luis O. B.

“…Stressors of various kinds constantly affect fish both in the wild and in culture, examples being acute water temperature and quality changes, predation,…”
Get full text

C-NMR Regioisomeric Analysis of EPA and DHA in Fish Oil Derived Triacylglycerol Concentrates by Suárez, Erick Reyes, Mugford, Paul F, Rolle, Alfred J, Burton, Ian W, Walter, John A, Kralovec, Jaroslav A

“…The regio-isomeric distribution of the omega-3 polyunsaturated fatty acids (PUFA) cis-5,8,11,14,17-eicosapentaenoic acid (EPA) and…”
Get full text

Isolation and Structure of Prorocentrolide B, a Fast-Acting Toxin from Prorocentrum maculosum by Hu, Tingmo, deFreitas, Anthony S. W, Curtis, Jonathan M, Oshima, Yasukatsu, Walter, John A, Wright, Jeffrey L. C

“…A new toxin, prorocentrolide B (1), has been isolated following bioassay-guided fractionation of a BuOH extract of the tropical dinoflagellate, Prorocentrum…”
Get full text

Spirolides Isolated from Danish Strains of the Toxigenic Dinoflagellate Alexandrium ostenfeldii by MACKINNON, Shawna L., WALTER, John A., QUILLIAM, Michael A., CEMBELLA, Allan D., LEBLANC, Patricia, BURTON, Ian W., HARDSTAFF, William R., LEWIS, Nancy I.

“…Using LC/MS methodology, spirolides were detected in two clonal isolates of Alexandrium ostenfeldii isolated from Limfjorden, Denmark. Examination of the LC/MS…”
Get full text

Biosynthesis of 13-Desmethyl Spirolide C by the Dinoflagellate Alexandrium ostenfeldii by MACKINNON, Shawna L., CEMBELLA, Allan D., BURTON, Ian W., LEWIS, Nancy, LEBLANC, Patricia, WALTER, John A.

“…Biosynthetic origins of the cyclic imine toxin 13-desmethyl spirolide C were determined by supplementing cultures of the toxigenic dinoflagellate Alexandrium…”
Get full text

H-NMR and mass spectrometric characterization of the metabolic response of juvenile Atlantic salmon (Salmo salar) to long-term handling stress by Karakach, Tobias K, Huenupi, Elizabeth C, Soo, Evelyn C, Walter, John A, Afonso, Luis O. B

“…Stressors of various kinds constantly affect fish both in the wild and in culture, examples being acute water temperature and quality changes, predation,…”
Get full text

Alterations in urinary metabolites due to unilateral ureteral obstruction in a rodent model by MacLellan, Dawn L, Mataija, Diane, Doucette, Alan, Huang, Weei, Langlois, Chantale, Trottier, Greg, Burton, Ian W, Walter, John A, Karakach, Tobias K

“…Urinary tract obstruction (UTO) results in renal compensatory mechanisms and may progress to irrecoverable functional loss and histologic alterations. The…”
Get more information

New Diol Esters Isolated from Cultures of the Dinoflagellates Prorocentrum lima and Prorocentrum concavum by Hu, Tingmo, Marr, Julie, de Freitas, Anthony S. W, Quilliam, Michael A, Walter, John A, Wright, Jeffrey L. C, Pleasance, Stephen

Get full text

NMR metabolic analysis of samples using fuzzy K-means clustering by Čuperlović-Culf, Miroslava, Belacel, Nabil, Culf, Adrian S., Chute, Ian C., Ouellette, Rodney J., Burton, Ian W., Karakach, Tobias K., Walter, John A.

“…The global analysis of metabolites can be used to define the phenotypes of cells, tissues or organisms. Classifying groups of samples based on their metabolic…”
Get full text

Characterization of the measurement error structure in 1D 1H NMR data for metabolomics studies by Karakach, Tobias K., Wentzell, Peter D., Walter, John A.

“…NMR-based metabolomics is characterized by high throughput measurements of the signal intensities of complex mixtures of metabolites in biological samples by…”
Get full text

Identification of Pectenotoxin-11 as 34S-Hydroxypectenotoxin-2, a New Pectenotoxin Analogue in the Toxic Dinoflagellate Dinophysis acuta from New Zealand by Suzuki, Toshiyuki, Walter, John A, LeBlanc, Patricia, MacKinnon, Shawna, Miles, Christopher O, Wilkins, Alistair L, Munday, Rex, Beuzenberg, Veronica, MacKenzie, A. Lincoln, Jensen, Dwayne J, Cooney, Janine M, Quilliam, Michael A

“…A new pectenotoxin, which has been named pectenotoxin-11 (PTX11), was isolated from the dinoflagellate Dinophysis acuta collected from the west coast of New…”
Get full text

13C-NMR Regioisomeric Analysis of EPA and DHA in Fish Oil Derived Triacylglycerol Concentrates by Suárez, Erick Reyes, Mugford, Paul F., Rolle, Alfred J., Burton, Ian W., Walter, John A., Kralovec, Jaroslav A.

“…The regio-isomeric distribution of the omega-3 polyunsaturated fatty acids (PUFA) cis -5,8,11,14,17-eicosapentaenoic acid (EPA) and cis…”
Get full text