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Journal articles on the topic 'Tyrosine – Measurement'

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Published: 4 June 2021

Last updated: 1 February 2022

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1

Li, Yong Jin. "Optical Determination of L-tyrosine Based on Eggshell Membrane Immobilized Tyrosinase." Journal of AOAC INTERNATIONAL 93, no. 6 (November 1, 2010): 1912–15. http://dx.doi.org/10.1093/jaoac/93.6.1912.

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Abstract An optical biosensor based on the eggshell membrane immobilized tyrosinase is described for the detection of L-tyrosine (L-Tyr). The detection scheme was based on the measurement of absorption value of color adduct resulting from the reaction of 3-methyl-2-benzothiazolinone hydrazone and dopa-quinone produced from the enzymatic oxidation of L-Tyr. The prepared biosensor demonstrated optimum activity at pH 7, optimum temperature range of 2040C and a linear response for the L-Tyr concentration in range of 5200 M. It also showed good operation stability for repeated measurements (over 300 times) and storage stability after it had been kept at 4C for 3 months.

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2

FROST, Matthew T., Barry HALLIWELL, and Kevin P. MOORE. "Analysis of free and protein-bound nitrotyrosine in human plasma by a gas chromatography/mass spectrometry method that avoids nitration artifacts." Biochemical Journal 345, no. 3 (January 25, 2000): 453–58. http://dx.doi.org/10.1042/bj3450453.

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Measurement of nitrotyrosine in biological fluids and tissues is increasingly being used to monitor the production of reactive nitrogen species in vivo. The detection of nitrotyrosine in vivo has been reported with the use of a variety of methods including immunoassay, HPLC and GLC/MS. The validity of HPLC and immunoassays have been questioned with regard to their selectivity and sensitivity limits. In principle, the measurement of nitrotyrosine by GLC/MS permits a highly specific, highly sensitive and fully quantitative assay. The nitration of tyrosine under acidic conditions in the presence of nitrite is well documented. Derivatization for the full quantification of nitrotyrosine by using GLC/MS can lead to the artifactual nitration of tyrosine if performed under acidic conditions in the presence of nitrite. We describe a novel alkaline method for the hydrolysis and derivatization of nitrotyrosine and tyrosine, and demonstrate its applicability to the measurement of plasma concentrations of both free and protein-bound nitrotyrosine and tyrosine. A detection limit of 1 pg for nitrotyrosine and 100 pg for tyrosine has been achieved. Our method allows, for the first time, the analysis of free and protein-bound nitrotyrosine and tyrosine in biological samples. The plasma concentrations (means±S.E.M.) of free tyrosine and nitrotyrosine in eight normal subjects were 12±0.6 μg/ml and 14±0.7 ng/ml respectively. Plasma proteins contained tyrosine and nitrotyrosine at 60.7±1.7 μg/mg and 2.7±0.4 ng/mg respectively.

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3

Shimizu, H., K. Taniguchi, M. Sugiyama, and T. Kanno. "Rapid enzymatic analysis of plasma for tyrosine." Clinical Chemistry 36, no. 1 (January 1, 1990): 32–35. http://dx.doi.org/10.1093/clinchem/36.1.32.

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Abstract In this rapid, simple, and convenient enzymatic method for measurement of tyrosine in plasma, tyrosine is converted to tyramine by action of tyrosine decarboxylase (EC 4.1.1.25) and the tyramine produced is oxidized to p-hydroxybenzyl aldehyde and hydrogen peroxide by action of tyramine oxidase (EC 1.4.3.9). The hydrogen peroxide is reacted with 4-aminoantipyrine and N-ethyl-N-(2-hydroxy-3-sulfopropyl)-m-toluidine in the presence of peroxidase (EC 1.11.1.7) to obtain quinoneimine dye, the absorbance of which is measured at 570 nm. Thus tyrosine is measured in the visible range. The CV was 4.6% or less, and the measurement was unaffected by other amino acids, except for phenylalanine. The values obtained (y) correlated well with those obtained with an amino acid analyzer (x): y = 0.902x + 3.92 mumol/L (Syx = 12.3; r = 0.985; n = 54).

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4

Eser, Bekir E., and Paul F. Fitzpatrick. "Measurement of Intrinsic Rate Constants in the Tyrosine Hydroxylase Reaction." Biochemistry 49, no. 3 (January 26, 2010): 645–52. http://dx.doi.org/10.1021/bi901874e.

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5

Chung, Inhee. "Optical measurement of receptor tyrosine kinase oligomerization on live cells." Biochimica et Biophysica Acta (BBA) - Biomembranes 1859, no. 9 (September 2017): 1436–44. http://dx.doi.org/10.1016/j.bbamem.2017.03.026.

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6

Yang, Yu, Liang-Hong Guo, Na Qu, Ming-Yuan Wei, Li-Xia Zhao, and Bin Wan. "Label-free electrochemical measurement of protein tyrosine kinase activity and inhibition based on electro-catalyzed tyrosine signaling." Biosensors and Bioelectronics 28, no. 1 (October 2011): 284–90. http://dx.doi.org/10.1016/j.bios.2011.07.033.

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7

Wei, Lan-Yi, Wei Lin, Bey-Fen Leo, Lik-Voon Kiew, Chia-Ching Chang, and Chiun-Jye Yuan. "Development of the Sensing Platform for Protein Tyrosine Kinase Activity." Biosensors 11, no. 7 (July 15, 2021): 240. http://dx.doi.org/10.3390/bios11070240.

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A miniature tyrosinase-based electrochemical sensing platform for label-free detection of protein tyrosine kinase activity was developed in this study. The developed miniature sensing platform can detect the substrate peptides for tyrosine kinases, such as c-Src, Hck and Her2, in a low sample volume (1–2 μL). The developed sensing platform exhibited a high reproducibility for repetitive measurement with an RSD (relative standard deviation) of 6.6%. The developed sensing platform can detect the Hck and Her2 in a linear range of 1–200 U/mL with the detection limit of 1 U/mL. The sensing platform was also effective in assessing the specificity and efficacies of the inhibitors for protein tyrosine kinases. This is demonstrated by the detection of significant inhibition of Hck (~88.1%, but not Her2) by the Src inhibitor 1, an inhibitor for Src family kinases, as well as the significant inhibition of Her2 (~91%, but not Hck) by CP-724714 through the platform. These results suggest the potential of the developed miniature sensing platform as an effective tool for detecting different protein tyrosine kinase activity and for accessing the inhibitory effect of various inhibitors to these kinases.

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8

DeFelippis, Michael R., C. P. Murthy, M. Faraggi, and Michael H. Klapper. "Pulse radiolytic measurement of redox potentials: the tyrosine and tryptophan radicals." Biochemistry 28, no. 11 (May 30, 1989): 4847–53. http://dx.doi.org/10.1021/bi00437a049.

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9

Mccaig, T. N., D. Y. K. Fenn, R. E. Knox, R. M. Depauw, J. M. Clarke, and J. G. Mcleod. "Measuring polyphenol oxidase activity in a wheat breeding program." Canadian Journal of Plant Science 79, no. 4 (October 1, 1999): 507–14. http://dx.doi.org/10.4141/p98-135.

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High levels of polyphenol oxidase (PPO) have been associated with discoloration of end-use products of wheat, especially certain noodle types. Two whole-seed methods of measuring PPO, one based on 10 mM tyrosine as substrate and the other on 90 mM catechol, were examined and modified to determine their potential as screening tools in large-scale breeding programs. Thirteen spring wheat and two spring triticale genotypes were used to compare the methods. Both methods could measure PPO on individual seeds. All genotypes displayed large seed-to-seed variation for PPO with both substrates. The mean coefficient of variation for the PPO values of individual seeds within genotypes was 39% with tyrosine and 34% with catechol. Furthermore, the PPO values of individual seeds within genotypes were not normally distributed for most genotypes. Identifying genotypes with incremental improvements in PPO would probably require measurement of 70–100 seeds. Approximately 50% of the catecholase activity was associated with the water extract after soaking seeds for 16 h, while all of the tyrosinase activity was still associated with the seed, suggesting that different enzymes are responsible for oxidizing tyrosine and catechol in wheat. While the 10 mM tyrosine assay was nondestructive and allowed plants to be generated from seeds low in PPO, 90 mM catechol reduced germination to less than 20%. Reducing the catechol to 30 mM improved germination to 85%, did not substrate-limit the reaction, and reduced the health risk associated with the assay. Spectral and kinetic differences between the assays were also considered. Key words: Triticum sp., wheat, polyphenol oxidase, catechol, tyrosine

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10

Kobayashi, Tomoko, Shun-Ichi Nakamura, and Hirohei Yamamura. "Cytosolic Protein-Tyrosine Kinase Activities in Various Rat Tissues." Annals of Clinical Biochemistry: International Journal of Laboratory Medicine 26, no. 2 (March 1989): 164–68. http://dx.doi.org/10.1177/000456328902600213.

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Suitable assay conditions for the detection of cytosolic protein-tyrosine kinase activities in crude extracts of various rat tissues have been determined. Cytosolic protein-tyrosine kinases showed common characteristics including substrate specificity and divalent cation requirement. Using (Val5) angiotensin II and Mn2+ rather than a src-related synthetic peptide, E11G1, and Mg2+, we obtained higher activities of cytosolic protein-tyrosine kinases. Among various rat tissues tested, spleen, bone marrow, thymus, small intestine, appendix and lung, in decreasing order of total activity, contained high activities of cytosolic protein-tyrosine kinases. These results suggest that the enzyme activities in lymphatic organs and in organs closely related to cell proliferation are high. The assay system described allows the precise measurement of cytosolic protein-tyrosine kinase activity in various rat tissues, both normal and malignant.

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11

Phillips, Ryan M., Eric Bair, David S. Lawrence, Christopher E. Sims, and Nancy L. Allbritton. "Measurement of Protein Tyrosine Phosphatase Activity in Single Cells by Capillary Electrophoresis." Analytical Chemistry 85, no. 12 (May 30, 2013): 6136–42. http://dx.doi.org/10.1021/ac401106e.

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12

Ladbury, John E. "Measurement of the formation of complexes in tyrosine kinase-mediated signal transduction." Acta Crystallographica Section D Biological Crystallography 63, no. 1 (December 13, 2006): 26–31. http://dx.doi.org/10.1107/s0907444906046373.

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13

Ge, Gaoxiang, Jing Wu, and Qishui Lin. "Non-radioisotopic method for thein vitro measurement of EGF receptor tyrosine kinase." Chinese Science Bulletin 46, no. 8 (April 2001): 683–85. http://dx.doi.org/10.1007/bf03182836.

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14

Skorey, Kathryn, Deena Waddleton, Michel Therien, and Tammy Leriche. "Enzyme occupancy measurement of intracellular protein tyrosine phosphatase 1B using photoaffinity probes." Analytical Biochemistry 349, no. 1 (February 2006): 49–61. http://dx.doi.org/10.1016/j.ab.2005.11.018.

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15

Ren, Haixia, Licheng Wang, Xusheng Wang, Xia Liu, and Shengxiang Jiang. "Measurement of acid dissociation constants and ionic mobilities of 3-nitro-tyrosine and 3-chloro-tyrosine by capillary zone electrophoresis." Journal of Pharmaceutical and Biomedical Analysis 77 (April 2013): 83–87. http://dx.doi.org/10.1016/j.jpba.2013.01.015.

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16

Baldwin, Graham S., Michael F. Bailey, B. Philip Shehan, Ioulia Sims, and Raymond S. Norton. "Tyrosine modification enhances metal-ion binding." Biochemical Journal 416, no. 1 (October 28, 2008): 77–84. http://dx.doi.org/10.1042/bj20081059.

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Tyrosine sulfation is a common modification of many proteins, and the ability to phosphorylate tyrosine residues is an intrinsic property of many growth-factor receptors. In the present study, we have utilized the peptide hormone CCK8 (cholecystokinin), which occurs naturally in both sulfated and unsulfated forms, as a model to investigate the effect of tyrosine modification on metal-ion binding. The changes in absorbance and fluorescence emission on Fe3+ binding indicated that tyrosine sulfation or phosphorylation increased the stoichiometry from 1 to 2, without greatly affecting the affinity (0.6–2.8 μM at pH 6.5). Measurement of Ca2+ binding with a Ca2+-selective electrode revealed that phosphorylated CCK8 bound two Ca2+ ions. CCK8 and sulfated CCK8 each bound only one Ca2+ ion with lower affinity. Binding of Ca2+, Zn2+ or Bi3+ to phosphorylated CCK8 did not cause any change in absorbance, but substantially increased the change in absorbance on subsequent addition of Fe3+. The results of the present study demonstrate that tyrosine modification may increase the affinity of metal-ion binding to peptides, and imply that metal ions may directly regulate many signalling pathways.

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17

Yu, Jingui, Koji Ogawa, Yasuyuki Tokinaga, Kazuhiro Mizumoto, Tetsuya Kakutani, and Yoshio Hatano. "The Inhibitory Effects of Isoflurane on Protein Tyrosine Phosphorylation–modulated Contraction of Rat Aortic Smooth Muscle." Anesthesiology 101, no. 6 (December 1, 2004): 1325–31. http://dx.doi.org/10.1097/00000542-200412000-00012.

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Background Tyrosine kinase-catalyzed protein tyrosine phosphorylation plays an important role in initiating and modulating vascular smooth muscle contraction. The aim of the current study was to examine the effects of isoflurane on sodium orthovanadate (Na3VO4), a potent protein tyrosine phosphatase inhibitor-induced, tyrosine phosphorylation-mediated contraction of rat aortic smooth muscle. Methods The Na3VO4-induced contraction of rat aortic smooth muscle and tyrosine phosphorylation of proteins including phospholipase Cgamma-1 (PLCgamma-1) and p44/p42 mitogen-activated protein kinase (MAPK) were assessed in the presence of different concentrations of isoflurane, using isometric force measurement and Western blotting methods, respectively. Results Na3VO4 (10(-4) m) induced a gradually sustained contraction and significant increase in protein tyrosine phosphorylation of a set of substrates including PLCgamma-1 and p42MAPK, all of which were markedly inhibited by genistein (5 x 10(-5) m), a tyrosine kinase inhibitor. Isoflurane (1.2-3.5%) dose-dependently depressed the Na3VO4-induced contraction (P < 0.05-0.005; n = 8). Isoflurane also attenuated the total density of the Na3VO4-induced, tyrosine-phosphorylated substrate bands and the density of tyrosine-phosphorylated PLCgamma-1 band and p42MAPK band (P < 0.05-0.005; n = 4) in a concentration-dependent manner. Conclusion The findings of the current study, that isoflurane dose-dependently inhibits both the Na3VO4-stimulated contraction and tyrosine phosphorylation of a set of proteins including PLCgamma-1 and p42MAPK in rat aortic smooth muscle, suggest that isoflurane depresses protein tyrosine phosphorylation-modulated contraction of vascular smooth muscle, especially that mediated by the tyrosine-phosphorylated PLCgamma-1 and MAPK signaling pathways.

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18

Cheah, Tat Beng, Larisa Bobrovskaya, Carlos-Alberto Gonçalves, Amanda Hall, Robert Elliot, Imre Lengyel, Stephen J. Bunn, Philip D. Marley, and Peter R. Dunkley. "Simultaneous measurement of tyrosine hydroxylase activity and phosphorylation in bovine adrenal chromaffin cells." Journal of Neuroscience Methods 87, no. 2 (March 1999): 167–74. http://dx.doi.org/10.1016/s0165-0270(99)00002-3.

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19

Poljak, A., R. Pamphlett, M. E. Gurney, and M. W. Duncan. "Measurement ofo- andm-tyrosine as markers of oxidative damage in motor neuron disease." Redox Report 5, no. 2-3 (April 2000): 137–40. http://dx.doi.org/10.1179/135100000101535483.

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20

García-Molina, Pablo, José Luis Munoz-Munoz, Joaquin A. Ortuño, José Neptuno Rodríguez-López, Pedro Antonio García-Ruiz, Francisco García-Cánovas, and Francisco García-Molina. "Considerations about the Continuous Assay Methods, Spectrophotometric and Spectrofluorometric, of the Monophenolase Activity of Tyrosinase." Biomolecules 11, no. 9 (August 25, 2021): 1269. http://dx.doi.org/10.3390/biom11091269.

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With the purpose to obtain the more useful tyrosinase assay for the monophenolase activity of tyrosinase between the spectrofluorometric and spectrophotometric continuous assays, simulated assays were made by means of numerical integration of the equations that characterize the mechanism of monophenolase activity. These assays showed that the rate of disappearance of monophenol (VssM,M) is equal to the rate of accumulation of dopachrome (VssM,DC) or to the rate of accumulation of its oxidized adduct, originated by the nucleophilic attack on o-quinone by a nucleophile such as 3-methyl-2-benzothiazolinone (MBTH), (VssM, A−ox), despite the existence of coupled reactions. It is shown that the spectrophotometric methods that use MBTH are more useful, as they do not have the restrictions of the L-tyrosine disappearance measurement method, of working at pH = 8 and not having a linear response from 100 μM of L-tyrosine. It is possible to obtain low LODM (limit of detection of the monophenolase activity) values with spectrophotometric methods. The spectrofluorimetric methods had a lower LODM than spectrophotometric methods. In the case of 4-hydroxyphenil-propionic acid, the LODM obtained by us was 0.25 U/mL. Considering the relative sensitivities of 4-hydroxyanisole, compared with 4-hydroxyphenil-propionic acid, LODM values like those obtained by fluorescent methods would be expected.

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21

Thompson, G. N., P. J. Pacy, H. Merritt, G. C. Ford, M. A. Read, K. N. Cheng, and D. Halliday. "Rapid measurement of whole body and forearm protein turnover using a [2H5]phenylalanine model." American Journal of Physiology-Endocrinology and Metabolism 256, no. 5 (May 1, 1989): E631—E639. http://dx.doi.org/10.1152/ajpendo.1989.256.5.e631.

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Whole body protein turnover was measured in six normal adults using a model based on a primed constant infusion of [2H5]phenylalanine and, independently, by an established method of a primed constant infusion of [1-13C]leucine. Isotopic plateau in plasma was achieved within 2 h for [2H5]phenylalanine and, in four of the subjects who received a priming dose of [2H4]tyrosine, for [2H4]tyrosine. In all subjects whole body protein turnover measured with the phenylalanine model (mean protein synthesis, 2.65 +/- (SD) 0.16 g.kg-1.24 h-1; catabolism, 3.58 +/- 0.26 g.kg-1.24 h-1) was similar to that measured using the leucine model (synthesis, 3.09 +/- 0.27 g.kg-1.24 h-1; catabolism, 3.70 +/- 0.35 g.kg-1.24 h-1). Mean forearm fractional muscle protein synthesis calculated by the phenylalanine model was 0.06 +/- 0.03%/h, which compares closely with literature values derived by other methods. The phenylalanine model allows the rapid assessment of whole body and muscle protein turnover from plasma samples alone, obviating the need for measurement of expired air CO2 production or enrichment.

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22

CHUAQUI-OFFERMANNS, NOEMI, and TOM MCDOUGALL. "Background Levels and Radiation Dose Yield of o-Tyrosine in Chicken Meat." Journal of Food Protection 54, no. 12 (December 1, 1991): 935–38. http://dx.doi.org/10.4315/0362-028x-54.12.935.

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The measurement of o-tyrosine levels in poultry meat is a potential method for postirradiation dosimetry of poultry. The validity of using o-tyrosine for this purpose has not yet been established. As part of the validation process, the o-tyrosine content in unirradiated chicken meat, the radiation dose response curve, and the effects of postirradiation storage on o-tyrosine levels are examined. In 18 individual samples, the mean background level of o-tyrosine was 0.18 ± 0.11 ppm (wet weight, 70% moisture), and the most frequent background level (60% of the cases) was between 0.05 and 0.15 ppm (wet weight, 70% moisture). In pooled samples of 10 chickens, the mean background level was 0.12 ± 0.03 ppm (wet weight, 70% moisture). The levels were not significantly affected by storage at 5°C (7 d) or by freezing the sample. The radiation dose response curve was linear within the dose range studied (0 to 10 kGy), with a slope of 0.127 ± 0.003 ppm (wet weight)/kGy. Although there was some variation in the intercept (0.132 ± 0.013), the slope was the same in all samples tested. Postirradiation storage at either 4 or 8°C until spoilage did not affect the levels of o-tyrosine. These data indicate that o-tyrosine level may be useful for determining the absorbed dose in chicken meat gamma-irradiated to doses greater than 0.6 kGy. Further validation studies are continuing.

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23

Blumenthal, Edward M. "Regulation of chloride permeability by endogenously produced tyramine in the Drosophila Malpighian tubule." American Journal of Physiology-Cell Physiology 284, no. 3 (March 1, 2003): C718—C728. http://dx.doi.org/10.1152/ajpcell.00359.2002.

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The Malpighian (renal) tubule of Drosophila melanogaster is a useful model for studying epithelial transport. The purpose of this study was to identify factors responsible for modulating transepithelial chloride conductance in isolated tubules. I have found that tyrosine and several of its metabolites cause an increase in chloride conductance. The most potent of these agonists is tyramine, which is active at low nanomolar concentrations; the pharmacology of this response matches that of the previously published cloned insect tyramine receptor. In addition, the tubule appears capable of synthesizing tyramine from applied tyrosine, as shown by direct measurement of tyrosine decarboxylase activity. Immunohistochemical staining of tubules with an antibody against tyramine indicates that the principal cells are the sites of tyramine production, whereas previous characterization of the regulation of chloride conductance suggests that tyramine acts on the stellate cells. This is the first demonstration of a physiological role for an insect tyramine receptor.

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24

Turner, Abigail H., Michael S. Lebhar, Angela Proctor, Qunzhao Wang, David S. Lawrence, and Nancy L. Allbritton. "Rational Design of a Dephosphorylation-Resistant Reporter Enables Single-Cell Measurement of Tyrosine Kinase Activity." ACS Chemical Biology 11, no. 2 (December 4, 2015): 355–62. http://dx.doi.org/10.1021/acschembio.5b00667.

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25

Paans, Anne M. J., Jan Pruim, Aren Van Waarde, Antonius T. M. Willemsen, and Willem Vaalburg. "Radiolabelled tyrosine for the measurement of protein synthesis rate in vivo by positron emission tomography." Baillière's Clinical Endocrinology and Metabolism 10, no. 4 (October 1996): 497–510. http://dx.doi.org/10.1016/s0950-351x(96)80666-5.

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26

Batenjany, Michael, David Bartnicki, Yuping Ambuel, Gregory Wiepz, Paul Bertics, and Scott Hayes. "Rapid, ELISA-based measurement of protein tyrosine kinase activity using the K-LISA™ Kit." Nature Methods 2, no. 9 (August 23, 2005): iv—v. http://dx.doi.org/10.1038/nmeth788.

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27

Neurauter, Gabriele, Sabine Scholl-Bürgi, Astrid Haara, Simon Geisler, Peter Mayersbach, Harald Schennach, and Dietmar Fuchs. "Simultaneous measurement of phenylalanine and tyrosine by high performance liquid chromatography (HPLC) with fluorescence detection." Clinical Biochemistry 46, no. 18 (December 2013): 1848–51. http://dx.doi.org/10.1016/j.clinbiochem.2013.10.015.

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28

Sonne, James W. H., Corey Seavey, and Jason S. Groshong. "Rapid immunohistological measurement of tyrosine hydroxylase in rat midbrain by near-infrared instrument-based detection." Journal of Chemical Neuroanatomy 116 (October 2021): 101992. http://dx.doi.org/10.1016/j.jchemneu.2021.101992.

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Amatya, Neha, David Yin-wei Lin, and Amy H. Andreotti. "Dynamic regulatory features of the protein tyrosine kinases." Biochemical Society Transactions 47, no. 4 (August 8, 2019): 1101–16. http://dx.doi.org/10.1042/bst20180590.

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Abstract The SRC, Abelson murine leukemia viral oncogene homolog 1, TEC and C-terminal SRC Kinase families of non-receptor tyrosine kinases (collectively the Src module kinases) mediate an array of cellular signaling processes and are therapeutic targets in many disease states. Crystal structures of Src modules kinases provide valuable insights into the regulatory mechanisms that control activation and generate a framework from which drug discovery can advance. The conformational ensembles visited by these multidomain kinases in solution are also key features of the regulatory machinery controlling catalytic activity. Measurement of dynamic motions within kinases substantially augments information derived from crystal structures. In this review, we focus on a body of work that has transformed our understanding of non-receptor tyrosine kinase regulation from a static view to one that incorporates how fluctuations in conformational ensembles and dynamic motions influence activation status. Regulatory dynamic networks are often shared across and between kinase families while specific dynamic behavior distinguishes unique regulatory mechanisms for select kinases. Moreover, intrinsically dynamic regions of kinases likely play important regulatory roles that have only been partially explored. Since there is clear precedence that kinase inhibitors can exploit specific dynamic features, continued efforts to define conformational ensembles and dynamic allostery will be key to combating drug resistance and devising alternate treatments for kinase-associated diseases.

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Tantawy, Azza Abdel Gawad, Amira Abdel Moneam Adly, Eman Abdel Rahman Ismail, Omneya Ibrahim Youssef, and Mohamed ElSayed Ali. "Soluble fms-Like Tyrosine Kinase 1 as a Link Between Angiogenesis and Endothelial Dysfunction in Pediatric Patients With β-Thalassemia Intermedia." Clinical and Applied Thrombosis/Hemostasis 23, no. 8 (February 23, 2017): 943–50. http://dx.doi.org/10.1177/1076029617692879.

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Endothelial damage has been implicated in the pathogenesis of vascular complications in β-thalassemia intermedia (β-TI). Soluble fms-like tyrosine kinase 1 (sFLT-1) is a member of the vascular endothelial growth factor receptor (VEGFR) family. Soluble fms-like tyrosine kinase 1 is an antiangiogenic protein that induces endothelial dysfunction by adhering to and inhibiting VEGF and placenta growth factor. The aim of this study was to assess the level of sFLT-1 in 35 children and adolescents with β-TI, correlating it with markers of hemolysis and iron overload as well as cardiopulmonary complications. Patients were studied focusing on the history of cardiac disease, splenectomy, transfusion, chelation/hydroxyurea therapy, serum ferritin, and sFLT-1 levels. Echocardiography and measurement of carotid intima–media thickness (CIMT) were done for all participants. Soluble fms-like tyrosine kinase 1 was significantly higher in TI patients compared to the control group (median [interquartile range], 110 [80-155] pg/mL versus 70 [60-90] pg/mL; P < .001). Splenectomized patients and those who had pulmonary hypertension risk or heart disease had higher sFLT-1 levels than those without ( P < .001). The sFLT-1 cutoff value that differentiates patients with and without pulmonary hypertension risk or heart disease was determined. Soluble fms-like tyrosine kinase 1 was lower among patients who received chelation therapy and/or hydroxyurea. Significant positive relations were observed between sFLT-1 and lactate dehydrogenase, serum ferritin, liver iron concentration, tricuspid regurgitant jet velocity, and CIMT. We suggest that sFLT-1 represents a link between angiogenesis, endothelial dysfunction, and subclinical atherosclerosis. Measurement of sFLT-1 as a marker of vascular dysfunction in β-TI may provide utility for early identification of patients at increased risk of cardiopulmonary complications.

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31

Bourassa, Claude, Linh T. Nguyen, Kenneth D. Roberts, and Simone Chevalier. "Characterization of protein-tyrosine kinase activity in the canine prostate." Biochemistry and Cell Biology 69, no. 2-3 (February 1, 1991): 146–53. http://dx.doi.org/10.1139/o91-022.

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Following the measurement of the phosphorylation of the substrate poly(Glu80Na,Tyr20) and the analysis of the alkali-resistant phosphorylation of endogenous proteins, the protein-tyrosine kinase of the canine prostate was partially characterized with regard to its subcellular localization, as well as certain kinetic and molecular properties. This kinase was mainly found in the cytosolic fraction (75%); however, its specific activity was similar to that of the residual enzyme present in the particulate fraction. Conditions for optimal activity of both fractions were determined. Under these conditions, several endogenous phosphoproteins (44–63 kilodaltons upon electrophoresis) were alkali resistant and phosphotyrosine was present in all of the major ones (pp63, pp57, pp52, and pp44). The particulate protein-tyrosine kinase activity was partially solubilized (58%) with 0.5% Triton X-100; this percentage was increased to 85% in the presence of 0.25 M KCl. Upon gel filtration, both cytosolic and particulate kinases showed an apparent molecular mass of 44 kilodaltons; these enzymes also phosphorylated similar major alkali-resistant phosphoproteins. The soluble protein-tyrosine kinase, with a sedimentation coefficient of 4.0S and an isoelectric point of 5.5, could be separated from arginine esterase and prostatic acid phosphatase.Key words: protein-tyrosine kinase, phosphotyrosine, prostate, arginine esterase, acid phosphatase.

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32

Ebel, Dirk, Jost Müllenheim, Hendrik Südkamp, Thomas Bohlen, Jan Ferrari, Ragnar Huhn, Benedikt Preckel, and Wolfgang Schlack. "Role of Tyrosine Kinase in Desflurane-induced Preconditioning." Anesthesiology 100, no. 3 (March 1, 2004): 555–61. http://dx.doi.org/10.1097/00000542-200403000-00014.

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Background Short administration of volatile anesthetics preconditions myocardium and protects the heart against the consequences of subsequent ischemia. Activation of tyrosine kinase is implicated in ischemic preconditioning. The authors investigated whether desflurane-induced preconditioning depends on activation of tyrosine kinase. Methods Sixty-four rabbits were instrumented for measurement of left ventricular pressure, cardiac output, and myocardial infarct size (IS). All rabbits were subjected to 30 min of occlusion of a major coronary artery and 2 h of subsequent reperfusion. Rabbits underwent a treatment period consisting of either no intervention for 35 min (control group, n = 12) or 15 min of 1 minimum alveolar concentration desflurane inhalation followed by a 10-min washout period (desflurane group, n = 12). Four additional groups received the tyrosine kinase inhibitor genistein (5 mg/kg) or lavendustin A (1.3 mg/kg) at the beginning of the treatment period with (desflurane-genistein group, n = 11; desflurane-lavendustin A group, n = 12) or without desflurane inhalation (genistein group, n = 9; lavendustin A group, n = 8). Results Hemodynamic values were similar in all groups during baseline (left ventricular pressure, 87 +/- 14 mmHg (mean +/- SD]; cardiac output, 198 +/- 47 ml/min), during coronary artery occlusion (left ventricular pressure, 78 +/- 12 mmHg; cardiac output, 173 +/- 39 ml/min), and after 2 h of reperfusion (left ventricular pressure, 59 +/- 17; cardiac output, 154 +/- 43 ml/min). IS in the control group was 55 +/- 10% of the area at risk. The tyrosine inhibitors had no effect on IS (genistein group, 56 +/- 13%; lavendustin A group, 49 +/- 13%; each P = 1.0 vs. control group). Desflurane preconditioning reduced IS to 40 +/- 15% (P = 0.04 vs. control group). Tyrosine kinase inhibitor administration had no effect on IS reduction (desflurane-genistein group, 44 +/- 13%; desflurane-lavendustin A group, 44 +/- 16%; each P = 1.0 vs. desflurane group). Conclusion Desflurane-induced preconditioning does not depend on tyrosine kinase activation.

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Freedman, Steven D., Mark H. Katz, Eliza M. Parker, and Andres Gelrud. "Endocytosis at the apical plasma membrane of pancreatic acinar cells is regulated by tyrosine kinases." American Journal of Physiology-Cell Physiology 276, no. 2 (February 1, 1999): C306—C311. http://dx.doi.org/10.1152/ajpcell.1999.276.2.c306.

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We have shown that endocytosis at the apical plasma membrane of pancreatic acinar cells is regulated by the pH of the acinar lumen and is associated with cleavage of GP2, a glycosyl phosphatidylinositol-anchored protein. The aim of this study was to determine the transduction pathway by which endocytosis is activated. Apical endocytosis was studied in rat pancreatic acini by prestimulation with cholecystokinin followed by measurement of horseradish peroxidase (HRP) uptake. Lanthanum, staurosporine, and forskolin had no effect on HRP uptake. Cytochalasin D significantly inhibited endocytosis, indicating a dependence on actin filament integrity. Genistein and the specific tyrphostin inhibitor B42 also inhibited HRP uptake, implicating tyrosine kinases in the regulation of HRP uptake. With the use of an Src kinase-specific substrate, Src kinase activity was temporally related to activation of endocytosis. The tyrosine-dependent phosphorylation of an 85-kDa substrate in both rat and mouse pancreatic acini correlated with Src kinase activation and pH-dependent regulation of HRP uptake. These results indicate that apical endocytosis in acinar cells is associated with tyrosine kinase activation and is dependent on the actin cytoskeleton.

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Parker, James C., Claire L. Ivey, and Allan Tucker. "Phosphotyrosine phosphatase and tyrosine kinase inhibition modulate airway pressure-induced lung injury." Journal of Applied Physiology 85, no. 5 (November 1, 1998): 1753–61. http://dx.doi.org/10.1152/jappl.1998.85.5.1753.

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We determined whether drugs which modulate the state of protein tyrosine phosphorylation could alter the threshold for high airway pressure-induced microvascular injury in isolated perfused rat lungs. Lungs were ventilated for successive 30-min periods with peak inflation pressures (PIP) of 7, 20, 30, and 35 cmH2O followed by measurement of the capillary filtration coefficient ( K fc), a sensitive index of hydraulic conductance. In untreated control lungs, K fc increased by 1.3- and 3.3-fold relative to baseline (7 cmH2O PIP) after ventilation with 30 and 35 cmH2O PIP. However, in lungs treated with 100 μM phenylarsine oxide (a phosphotyrosine phosphatase inhibitor), K fc increased by 4.7- and 16.4-fold relative to baseline at these PIP values. In lungs treated with 50 μM genistein (a tyrosine kinase inhibitor), K fc increased significantly only at 35 cmH2O PIP, and the three groups were significantly different from each other. Thus phosphotyrosine phosphatase inhibition increased the susceptibility of rat lungs to high-PIP injury, and tyrosine kinase inhibition attenuated the injury relative to the high-PIP control lungs.

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Tomáska, L., and R. J. Resnick. "Involvement of a phosphotyrosine protein phosphatase in the suppression of platelet-derived growth factor receptor autophosphorylation in ras-transformed cells." Biochemical Journal 293, no. 1 (July 1, 1993): 215–21. http://dx.doi.org/10.1042/bj2930215.

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The nature of the suppression of platelet-derived growth factor (PDGF) receptor autophosphorylation in ras-transformed NIH 3T3 fibroblasts was investigated. The PDGF receptor from ras-transformed cells that had been purified by wheatgerm-lectin affinity chromatography displayed normal PDGF-induced autophosphorylation, indicating that the receptor is not irreversibly modified. Various phosphotyrosine-protein-phosphatase inhibitors did not reverse the inhibition of PDGF-receptor kinase in crude membrane preparations from ras-transformed cells. However, treatment of intact ras-transformed cells both with 2 mM sodium orthovanadate and with 20 microM phenylarsine oxide restored PDGF-receptor tyrosine-kinase activity to a level similar to that observed in normal cells. Direct measurement of the phosphatase activities in crude cellular fractions revealed a 2.5-fold higher membrane-associated phosphotyrosine-protein-phosphatase activity in ras-transformed cells, whereas phosphoserine-protein-phosphatase activity remained unchanged between the cell lines. These data suggest that the suppression of the PDGF-receptor tyrosine-kinase activity in ras-transformed cells is mediated via an inhibitory component, distinct from the receptor, that may be positively regulated by the dephosphorylation of tyrosine residue(s).

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Lee, Seung-Tae, Yeon Lim Suh, Young-Hyeh Ko, Chang-Seok Ki, Ki Woong Sung, Hee-Jin Kim, Jong-Won Kim, et al. "Measurement of tyrosine hydroxylase transcripts in bone marrow using biopsied tissue instead of aspirates for neuroblastoma." Pediatric Blood & Cancer 55, no. 2 (April 21, 2010): 273–78. http://dx.doi.org/10.1002/pbc.22483.

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Holme, P. C., and K. A. Woods. "Measurement of plasma tyrosine by HPLC-UV or LC-MS-MS for assessing chemically induced tyrosinaemia." Chromatographia 55, S1 (January 2002): S193—S194. http://dx.doi.org/10.1007/bf02493379.

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Takakusa, H., K. Kikuchi, and T. Nagano. "2G1645 Development of Novel Fluorescence Resonance Energy Transfer Probes for Ratiometric Measurement of Protein Tyrosine Phosphatase Activity." Seibutsu Butsuri 42, supplement2 (2002): S117. http://dx.doi.org/10.2142/biophys.42.s117_4.

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Larkin, Peter J., William G. Gustafson, and Sanford A. Asher. "A new Raman cross section measurement technique monitors the tyrosine environmental dependence of the electromagnetic field strength." Journal of Chemical Physics 94, no. 8 (April 15, 1991): 5324–30. http://dx.doi.org/10.1063/1.460517.

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Dale, Y., V. Mackey, R. Mushi, A. Nyanda, M. Maleque, and J. Ike. "Simultaneous measurement of phenylalanine and tyrosine in phenylketonuric plasma and dried blood by high-performance liquid chromatography." Journal of Chromatography B 788, no. 1 (May 2003): 1–8. http://dx.doi.org/10.1016/s1570-0232(02)01005-x.

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Kim, Kyonghee, and Philip A. Cole. "Measurement of a Brønsted Nucleophile Coefficient and Insights into the Transition State for a Protein Tyrosine Kinase." Journal of the American Chemical Society 119, no. 45 (November 1997): 11096–97. http://dx.doi.org/10.1021/ja972110k.

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Li, Bingyu, Xinhao Shi, Wei Gu, Kai Zhao, Ningning Chen, and Yuezhong Xian. "Graphene based electrochemical biosensor for label-free measurement of the activity and inhibition of protein tyrosine kinase." Analyst 138, no. 23 (2013): 7212. http://dx.doi.org/10.1039/c3an01483e.

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Braunwalder, Albert F., Donna R. Yarwood, Matthew A. Sills, and Kenneth E. Lipson. "Measurement of the Protein Tyrosine Kinase Activity of c-src Using Time-Resolved Fluorometry of Europium Chelates." Analytical Biochemistry 238, no. 2 (July 1996): 159–64. http://dx.doi.org/10.1006/abio.1996.0269.

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Qiuying, C., D. Zhou, Z. Abdel-Malek, P. Goff, E. Sviderskaya, K. Wakamatsu, S. Ito, S. Gross, and J. Zippin. "546 Measurement of melanin metabolism in live cells by [U-13C]-tyrosine fate tracing using LC-MS." Journal of Investigative Dermatology 141, no. 5 (May 2021): S95. http://dx.doi.org/10.1016/j.jid.2021.02.572.

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Reinhard, John F., and James P. O'Callaghan. "Measurement of tyrosine hydroxylase apoenzyme protein by enzyme-linked immunosorbent assay (ELISA): Effects of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) on striatal tyrosine hydroxylase activity and content." Analytical Biochemistry 196, no. 2 (August 1991): 296–301. http://dx.doi.org/10.1016/0003-2697(91)90469-a.

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Ueshima, Kazuhito, Yoshiaki Minakata, Hisatoshi Sugiura, Satoru Yanagisawa, Tomohiro Ichikawa, Keiichirou Akamatsu, Tsunahiko Hirano, et al. "The Influence of Free 3-Nitrotyrosine and Saliva on the Quantitative Analysis of Protein-Bound 3-Nitrotyrosine in Sputum." Analytical Chemistry Insights 2 (January 2007): 117739010700200. http://dx.doi.org/10.4137/117739010700200006.

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Background We have recently developed a new technique for quantitatively measuring protein-bound 3-nitrotyrosine (3-NT), a footprint of nitrosative stress, utilizing high-performance liquid chromatography with an electrochemical detection (HPLC-ECD) system. Using this system, we showed that 3-NT formation was upregulated in the sputum of both COPD and asthmatic patients. However, in order to improve the accuracy of the measurement system, We have to resolve some problems which were the influence of free amino acid form of 3-NT and of salivary contamination. Objectives We initially investigated the amount of the free amino acid form of 3-NT in induced sputum and compared with that of protein-bound 3-NT. Next, we evaluated the concentration of protein-bound 3-NT in saliva and compared with that in induced sputum by means of HPLC-ECD. Methods Five male COPD patients were enrolled. Induced sputum and saliva were obtained from the patients. The free amino acid form of 3-NT in sputum and saliva was measured by HPLC-ECD, and the protein-bound 3-NT and tyrosine in sputum and saliva were enzymatically hydrolyzed by Streptomyces griseus Pronase and measured for the protein hydrolysate by HPLC-ECD. Results The mean value of the amount of protein-bound 3-NT was 65.0 fmol (31.2 to 106.4 fmol). On the other hand, the amount of the free amino acid form of 3-NT was under the detection limit (<10 fmol). The levels of both 3-NT (sputum: 0.55 ± 0.15 pmol/ml, saliva: 0.02 ± 0.01 pmol/ml, p < 0.01) and tyrosine (sputum: 0.81 ± 0.43 μmol/ml, saliva: 0.07 ± 0.04 μmol/ml, p < 0.01) in saliva were significantly lower than in sputum. The percentage of 3-NT in saliva to that in sputum was about 3.1%, and that of tyrosine was about 9.0%. Conclusion The free amino acid form of 3-NT does not affect the measurement of protein-bound 3-NT. Furthermore, the influence of salivary contamination on the measurement of protein-bound 3-NT in induced sputum by means of HPLC-ECD was very small and could be negligible.

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Osorio, S., V. Escudero-Vilaplana, I. Gómez-Centurión, E. González-Arias, X. García-González, and JL Díez. "Inadequate response to imatinib treatment in chronic myeloid leukemia due to a drug interaction with phenytoin." Journal of Oncology Pharmacy Practice 25, no. 3 (December 3, 2017): 694–98. http://dx.doi.org/10.1177/1078155217743565.

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Imatinib mesylate and the newer BCR-ABL tyrosine kinase inhibitors are the standard therapy for chronic myeloid leukemia. Although these are remarkably effective drugs, some mechanisms of resistance have been identified including drug-to-drug interactions. Here we present the case of a chronic myeloid leukemia patient with an inadequate response to imatinib due to concurrent phenytoin administration. Conspicuously low imatinib plasma trough levels were documented. Imatinib dose was increased from 400 to 800 mg with good response. In conclusion, drug-to-drug interactions should be ruled out in cases of resistance to tyrosine kinase inhibitor treatment. Potent inducers of cytochrome P450 isoenzyme CYP3A4, as phenytoin, could induce inadequate responses due to increased imatinib clearance and low imatinib trough plasma levels. Thus, this interaction should be avoided. When this is not possible, dose escalation of imatinib and measurement of plasma levels, if available, is recommended.

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Smotrov, Nadya, Anjili Mathur, Ilona Kariv, Christopher M. Moxham, and Nathan Bays. "Development of a Cell-Based Assay for Measurement of c-Met Phosphorylation Using AlphaScreenTM Technology and High-Content Imaging Analysis." Journal of Biomolecular Screening 14, no. 4 (April 2009): 404–11. http://dx.doi.org/10.1177/1087057109331803.

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c-Met is a receptor tyrosine kinase (RTK) with a critical role in many fundamental cellular processes, including cell proliferation and differentiation. Deregulated c-Met signaling has been implicated in both the initiation and progression of human cancers and therefore represents an attractive target for anticancer therapy. Monitoring the phosphorylation status of relevant tyrosine residues provides an important method of assessing c-Met kinase activity. This report describes a novel assay to monitor c-Met phosphorylation in cells using Amplified Luminescent Proximity Homogeneous Assay (AlphaScreen™) technology. Using AlphaScreen™, the authors were able to detect both global and site-specific phosphorylation of c-Met in transformed cell lines. Data obtained from the AlphaScreen™ assay were compared to data obtained from a high-content imaging (HCI) method developed in parallel to monitor c-Met phosphorylation at the single cell level. The AlphaScreen™ assay was miniaturized to a 384-well format with acceptable signal-to-background ratio (S/B) and Z′ statistics and was employed to measure c-Met kinase activity in situ after treatment with potent c-Met-specific kinase inhibitors. The authors discuss the utility of quantifying endogenous cellular c-Met phosphorylation in lead optimization and how the modular design of the AlphaScreen™ assay allows its adaptation to measure cellular activity of other kinases. ( Journal of Biomolecular Screening 2009:404-411)

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Alrabiah, Ziyad, Abdulaziz Alhossan, Seongseok Yun, Karen MacDonald, and Ivo Abraham. "Adherence to Tyrosine Kinase Inhibitor Therapy in Patients with Chronic Myeloid Leukemia: Meta-Analyses of Prevalence Rates By Measurement Method." Blood 128, no. 22 (December 2, 2016): 3610. http://dx.doi.org/10.1182/blood.v128.22.3610.3610.

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Abstract Introduction: First- (imatinib) and second-generation (dasatinib, nilotinib) tyrosine kinase inhibitors are the standard of care in the management of chronic myeloid leukemia. Despite their high efficacy and the convenience of oral administration, studies have reported variation in patient medication behavior with non-adherence rates varying from low to moderate based on definition and measurement method. We conducted study-level meta-analyses stratified by measurement method to quantify adherence prevalence rates in chronic myeloid leukemia patients as reported in non-controlled "real-life" studies. Methods: We searched PubMed, Embase, and Cochrane Library for non-controlled studies reporting adherence or non-adherence rates to tyrosine kinase inhibitor treatment in chronic myeloid leukemia patients across various methods of measurement. For retained studies, adherence rates and 95% confidence interval (95% CI) were extracted or calculated; and grouped by method of measurement. Random-effects meta-analyses were performed to account for estimated (Q, I2, tau2) within and between study heterogeneity, and associated forest plots were generated. Analyses were done using Comprehensive Meta-Analysis V.3. Results: From 649 publications yielded by the search, 40 articles and abstracts were retained. Measurement methods included structured interview, medical/pharmacy chart review, medication possession ratio, proportion of days covered, electronic monitoring, and self-report. Electronic monitoring and self-report were used in one study each and thus excluded from meta-analysis. Table 1 summarizes, by the remaining four methods, the number of studies and patients included in each meta-analysis, the estimated adherence event rates with 95%CI, and heterogeneity indices. In random-effects analyses, adherence rate estimates as measured by each method ranged (in descending order) from 0.75 (95%CI=0.66-0.82) for structured interview, 0.68 (95%CI=0.54-0.79) for medical/pharmacy chart review, 0.57 (95%CI=0.47-0.67) for medication possession ratio, to 0.56 (95%CI=0.36-0.74) for proportion of days covered. All four analyses showed significant heterogeneity. Conclusion: Our meta-analyses using clinical data (structured interview; medical/pharmacy chart review) indicate that, while the majority of chronic myeloid leukemia patients are adherent to their tyrosine kinase inhibitor regimens, between 1/3rd and 1/4th of them are not. Indirect methods using prescription claims data (medication possession ratio; proportion of days covered) yielded lower adherence rates, though caution about such indirect results is warranted. Considering evidence linking adherence to impaired cytogenetic (Noens et al, Blood 2009) and molecular response (Marin et al, J Clin Oncol 2010), clinicians should integrate adherence assessment and enhancement into routine clinical practice. Table 1 Table 1. Disclosures MacDonald: Matrix45: Employment, Equity Ownership; Ex Ante International: Equity Ownership. Abraham:Matrix45: Equity Ownership; Belgamis: Equity Ownership; Ex Ante International: Equity Ownership.

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Kameda, Takahiro, Ryunosuke Ohkawa, Kouji Yano, Yoko Usami, Akari Miyazaki, Kazuyuki Matsuda, Kenji Kawasaki, Mitsutoshi Sugano, Tetsuo Kubota, and Minoru Tozuka. "Effects of Myeloperoxidase-Induced Oxidation on Antiatherogenic Functions of High-Density Lipoprotein." Journal of Lipids 2015 (2015): 1–8. http://dx.doi.org/10.1155/2015/592594.

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High-density lipoprotein (HDL) has protective effects against the development of atherosclerosis; these effects include reverse cholesterol transport, antioxidant ability, and anti-inflammation. Myeloperoxidase (MPO) secreted by macrophages in atherosclerotic lesions generates tyrosyl radicals in apolipoprotein A-I (apoA-I) molecules, inducing the formation of apoA-I/apoA-II heterodimers through the tyrosine-tyrosine bond in HDL. Functional characterization of HDL oxidized by MPO could provide useful information about the significance of apoA-I/apoA-II heterodimers measurement. We investigated the effects of MPO-induced oxidation on the antiatherogenic functions of HDL as described above. The antioxidant ability of HDL, estimated as the effect on LDL oxidation induced by copper sulfate, was not significantly affected after MPO oxidation. HDL reduced THP-1 monocyte migration by suppressing the stimulation of human umbilical vein endothelial cells induced by lipopolysaccharide (LPS). MPO-oxidized HDL also showed inhibition of THP-1 chemotaxis, but the extent of inhibition was significantly attenuated compared to intact HDL. MPO treatment did not affect the cholesterol efflux capacity of HDL from [3H]-cholesterol-laden macrophages derived from THP-1 cells. The principal effect of MPO oxidation on the antiatherogenic potential of HDL would be the reduction of anti-inflammatory ability, suggesting that measurement of apoA-I/apoA-II heterodimers might be useful to estimate anti-inflammatory ability of HDL.

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