89 results on '"Tawa M"'
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2. A Framework for Working With American Indian Parents.
- Author
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Witko, Tawa M., primary
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- 2006
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3. Growing Up Indian: Treatment With Urban Indian Adolescents.
- Author
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Clark, Rose L., primary and Witko, Tawa M., additional
- Published
- 2006
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4. Hand & Mind: Conversations on Architecture and the Built World
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Murray, A, Ruan, X, Margalit, H, Gusheh, M, Simon, K, Gamble, J, Hunter Hicks, L, Macken, M, Hawken, S, Prnjatovic, M, Melhem, C, Gallagher, L, Kite, C, Stewart, F, Hollenstein, M, Kimmel, L, Rosin, N, Favaro, P, Leuning, N, Van De Haar, S, Outram, C, Tran, S, Tawa, M, Self, J, Murray, A, Ruan, X, Margalit, H, Gusheh, M, Simon, K, Gamble, J, Hunter Hicks, L, Macken, M, Hawken, S, Prnjatovic, M, Melhem, C, Gallagher, L, Kite, C, Stewart, F, Hollenstein, M, Kimmel, L, Rosin, N, Favaro, P, Leuning, N, Van De Haar, S, Outram, C, Tran, S, Tawa, M, and Self, J
- Published
- 2018
5. A Framework for Working With American Indian Parents
- Author
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Tawa M. Witko
- Subjects
Psychology - Published
- 2006
6. Growing Up Indian: Treatment With Urban Indian Adolescents
- Author
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Tawa M. Witko and Rose L. Clark
- Subjects
Substance abuse ,medicine.medical_specialty ,medicine ,Anxiety ,Dual diagnosis ,Sociology ,medicine.symptom ,Social issues ,Psychiatry ,medicine.disease ,Socioeconomic status ,Mental health - Published
- 2006
7. Candidates' statements (Member-at-large--American Indian Slate)
- Author
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Witko, Tawa M., primary
- Published
- 2005
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8. Technical problems in image network system (1)
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Geshi, H, primary, Tohyama, Y, additional, Kubo, Y, additional, Yamamoto, N, additional, Hatakeyama, T, additional, Akagi, N, additional, Okino, K, additional, Yokota, N, additional, Tawa, M, additional, Itoh, K, additional, Morio, K, additional, Takemura, M, additional, Yamagata, N, additional, Yasunami, H, additional, and Sasaki, T., additional
- Published
- 1996
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9. Relief of low back pain immediately after acupuncture treatment -- a randomised, placebo controlled trial.
- Author
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Inoue M, Kitakoji H, Ishizaki N, Tawa M, Yano T, Katsumi Y, and Kawakita K
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ACUPUNCTURE ,BACKACHE ,RANDOMIZED controlled trials ,MEDICAL equipment ,ACUPUNCTURE points ,SHARPS (Medical instruments) ,ALTERNATIVE medicine - Abstract
Background The purpose of this study was to examine the immediate effect of single acupuncture stimulation to the most painful point in patients with low back pain.Method A randomised, evaluator-blinded, sham controlled clinical trial was conducted in which 31 patients with low back pain were randomly allocated to either an acupuncture group (n=15) or a sham acupuncture group (n=16). Both acupuncture and sham acupuncture were performed at the most painful point on the lower back of the subjects. For the acupuncture group, a stainless steel needle was inserted to a depth of 20mm and manually stimulated (sparrow pecking method) for 20 seconds, while for the sham treatment a guide tube without a needle was placed at the point and tapped on the skin. Changes in low back pain were evaluated with a visual analogue scale (VAS) and the Schober test. Participants were also asked if they felt the needling sensation or not. The therapy and the evaluation were independently performed by two different acupuncturists. Results VAS score and the Schober test score showed significant improvement after treatment as compared with the sham group (P=0.02, 0.001, respectively). There were no significant differences in the needling sensation between the acupuncture and sham group.Conclusion These results suggest that acupuncture at the most painful point gives immediate relief of low back pain. [ABSTRACT FROM AUTHOR]
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- 2006
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10. Synthesis and Molecular Structures of Perfluoro-n-alkyl Complexes of Platinum(II) and Platinum(IV) Containing Tetramethylethylenediamine (TMEDA) or 1,2-Bis(diphenylphosphino)ethane (DPPE) Ligands
- Author
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Hughes, R. P., Sweetser, J. T., Tawa, M. D., Williamson, A., Incarvito, C. D., Rhatigan, B., Rheingold, A. L., and Rossi, G.
- Abstract
Reaction of (TMEDA)Pt(CH
3 )2 with n-perfluoropropyl iodide in hexanes results in an apparent cis addition of the perfluoroalkyl iodide to give the six-coordinate Pt(IV) complex (TMEDA)Pt(n-C3 F7 )(CH3 )2 I (6a ). Complex6a slowly and reversibly reductively eliminates CH3 I in solution to afford an equilibrium with the Pt(II) complex (TMEDA)Pt(n-C3 F7 )(CH3 ) (9a ). Addition of triethylamine drives the equilibrium toward9a . Identical reactions of perfluoroethyl iodide are observed to afford6b and9b . Reaction of6a with AgBF4 generates the cationic Pt(IV) complex [(TMEDA)Pt(n-C3 F7 )(CH3 )2 (OH2 )]BF4 (11 ), which reacts with NaCl to form (TMEDA)Pt(n-C3 F7 )(CH3 )2 Cl (12 ); both reactions retain the cis stereochemistry of the starting material6a . Reaction of9a with CF3 SO3 H in moist solvents generates the cationic Pt(II) complex [(TMEDA)Pt(n-C3 F7 )(OH2 )]O3 SCF3 (17 ), which reacts with iodide to afford the neutral iodide complex (TMEDA)Pt(n-C3 F7 )I (14 ). Reaction of complex9a with I2 in hexanes results in trans addition of I2 to generate (TMEDA)Pt(C3 F7 )(CH3 )I2 (13 ), which is converted to (TMEDA)Pt(n-C3 F7 )I (7 ) by treatment with AgBF4 followed by NaI. Complex14 reacts with NaBH4 to produce (TMEDA)Pt(n-C3 F7 )H (18 ). The TMEDA ligand can be displaced from9a by DPPE to give (DPPE)Pt(n-C3 F7 )(CH3 ) (19 ), which reacts with CF3 SO3 H to give the triflate complex (DPPE)Pt(n-C3 F7 )O3 SCF3 (20 ), in equilibrium with a water complex, [(DPPE)Pt(n-C3 F7 )(OH2 )]O3 SCF3 (21 ). Reaction of20 with iodide, or19 with I2 , gives (DPPE)Pt(n-C3 F7 )I (22 ), which can be converted to the hydrido complex (DPPE)Pt(n-C3 F7 )H (23 ) with NaBH4 . The X-ray crystal structures of complexes6a ,9a ,9b ,10 ,13 ,18 ,19 ,20 , and23 have been determined, and structural comparisons in terms of ligand cis and trans influences are discussed.- Published
- 2001
11. Reversible suppression of normal thymic output in patients with leukemic cutaneous T cell lymphoma
- Author
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Emmanuella Guenova, Watanabe, R., Gehad, A., Teague, J. E., Adams, N., Dorosario, A. A., Glinert, R., Walsch, D., Tawa, M., Carter, J. B., Chaney, K. A., Fisher, D. C., Cutler, C. S., Kupper, T. S., and Clark, R. A.
12. IL-32 supports the survival of malignant T cells in cutaneous T cell lymphoma
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Yu, KK, primary, Smith, NP, additional, Essien, SV, additional, Teague, JE, additional, Vieyra-Garcia, P, additional, Gehad, A, additional, Zhan, Q, additional, Crouch, JD, additional, Gerard, N, additional, Larocca, C, additional, Wolf, P, additional, LeBoeuf, NR, additional, Tawa, M, additional, Kupper, TS, additional, Villani, A, additional, and Clark, RA, additional
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13. Efficacy of BAY 60-2770, a Soluble Guanylate Cyclase Activator, for Coronary Spasm in Animal Models.
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Tawa M, Nakagawa K, and Ohkita M
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- Animals, Dogs, Rats, Male, Swine, Guanylate Cyclase metabolism, Disease Models, Animal, Rats, Sprague-Dawley, Enzyme Activators pharmacology, Enzyme Activators therapeutic use, Vasoconstriction drug effects, Biphenyl Compounds, Soluble Guanylyl Cyclase metabolism, Coronary Vessels drug effects, Benzoates pharmacology, Benzoates therapeutic use, Hydrocarbons, Fluorinated pharmacology
- Abstract
Ischemia with non-obstructive coronary arteries (INOCA), caused by coronary artery spasm, has gained increasing attention owing to the poor quality of life of impacted patients. Therapeutic options to address INOCA remain limited, and developing new therapeutic agents is desirable. Here, we examined whether soluble guanylate cyclase (sGC) activators could be beneficial in preventing coronary spasms. In organ chamber experiments with isolated canine coronary arteries, prostaglandin F
2 α M) evoked a concentration-related relaxation to a greater extent in small (first diagonal branch) coronary arteries than in large (left anterior descending) coronary arteries. In vasopressin-induced angina model rats, pretreatment with BAY 60-2770 (3 µ M) evoked a concentration-related relaxation to a greater extent in small (first diagonal branch) coronary arteries than in large (left anterior descending) coronary arteries. In vasopressin-induced angina model rats, pretreatment with BAY 60-2770 (3 µ g/kg) suppressed electrocardiogram S-wave depression induced by arginine vasopressin without affecting changes in mean blood pressure and heart rate. These findings suggest that BAY 60-2770 could be valuable in preventing both large and small coronary spasms. Therefore, sGC activators could represent a novel and efficacious therapeutic option for INOCA. SIGNIFICANCE STATEMENT: The soluble guanylate cyclase (sGC) activator BAY 60-2770 exerted antispastic effects on the coronary arteries in animal vasospasm models as proof-of-concept studies. These data can help to support potential clinical development with sGC activators, suitable for human use in patients with vasospastic angina., (Copyright © 2024 by The American Society for Pharmacology and Experimental Therapeutics.)- Published
- 2024
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14. Phototherapy Restores Deficient Type I IFN Production and Enhances Antitumor Responses in Mycosis Fungoides.
- Author
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Yu Z, Vieyra-Garcia P, Benezeder T, Crouch JD, Kim IR, O'Malley JT, Devlin PM, Gehad A, Zhan Q, Gudjonsson JE, Sarkar MK, Kahlenberg JM, Gerard N, Teague JE, Kupper TS, LeBoeuf NR, Larocca C, Tawa M, Pomahac B, Talbot SG, Orgill DP, Wolf P, and Clark RA
- Subjects
- Humans, CD8-Positive T-Lymphocytes pathology, Phototherapy, Gene Expression, Skin Neoplasms therapy, Skin Neoplasms drug therapy, Mycosis Fungoides therapy, Mycosis Fungoides drug therapy, Furocoumarins therapeutic use
- Abstract
Transcriptional profiling demonstrated markedly reduced type I IFN gene expression in untreated mycosis fungoides (MF) skin lesions compared with that in healthy skin. Type I IFN expression in MF correlated with antigen-presenting cell-associated IRF5 before psoralen plus UVA therapy and epithelial ULBP2 after therapy, suggesting an enhancement of epithelial type I IFN. Immunostains confirmed reduced baseline type I IFN production in MF and increased levels after psoralen plus UVA treatment in responding patients. Effective tumor clearance was associated with increased type I IFN expression, enhanced recruitment of CD8
+ T cells into skin lesions, and expression of genes associated with antigen-specific T-cell activation. IFNk, a keratinocyte-derived inducer of type I IFNs, was increased by psoralen plus UVA therapy and expression correlated with upregulation of other type I IFNs. In vitro, deletion of keratinocyte IFNk decreased baseline and UVA-induced expression of type I IFN and IFN response genes. In summary, we find a baseline deficit in type I IFN production in MF that is restored by psoralen plus UVA therapy and correlates with enhanced antitumor responses. This may explain why MF generally develops in sun-protected skin and suggests that drugs that increase epithelial type I IFNs, including topical MEK and EGFR inhibitors, may be effective therapies for MF., (Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)- Published
- 2024
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15. Prevalence and implications of mogamulizumab-induced immune-related adverse events in mycosis fungoides/Sézary syndrome; a single-center experience.
- Author
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Jfri A, Virgen CA, Tawa M, Giobbie-Hurder A, Kupper TS, Fisher DC, LeBoeuf NR, and Larocca C
- Abstract
Competing Interests: Conflicts of interest T.S.K. is supported by the National Institute of Arthritis and Musculoskeletal and Skin Diseases (grant numbers R01 AR065807 and T32 AR007098) and the National Institute of Allergy and Infectious Diseases (grant number R01 AI127654). He is a scientific advisor for Pellis Therapeutics. N.R.L. is a consultant and has received honoraria from Bayer, Seattle Genetics, Sanofi, Silverback and Synox Therapeutics outside the submitted work. C.L. is supported by the National Cancer Institute (grant number R37 CA252312). She has served on a medical advisory board for Kyowa Kirin. The other authors declare no conflicts of interest with respect to the research, authorship and/or publication of this article.
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- 2023
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16. Mogamulizumab-Associated Myositis With and Without Myasthenia Gravis and/or Myocarditis in Patients With T-Cell Lymphoma.
- Author
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Virgen CA, Sparks JA, Nohria A, O'Hare MJ, Goyal A, Said JT, Tawa M, LeBoeuf NR, Kupper TS, Fisher DC, and Larocca C
- Subjects
- Humans, Retrospective Studies, Myocarditis chemically induced, Lymphoma, T-Cell, Lymphoma, T-Cell, Peripheral drug therapy, Myositis chemically induced, Myasthenia Gravis chemically induced, Myasthenia Gravis drug therapy
- Abstract
Mogamulizumab is being increasingly prescribed for the treatment of T-cell lymphomas (MF/SS/ATLL). We conducted a retrospective cohort study to identify muscular immune-related adverse events (irAEs) associated with mogamulizumab in patients with T-cell lymphoma followed at Dana-Farber Cancer Institute from January 2015 to June 2022. We identified 5 cases of mogamulizumab-associated myositis and/or myocarditis (MAM/Mc), 2 additionally affected by myasthenia gravis, among 42 patients with T-cell lymphoma. Three cases experienced -mogamulizumab-associated rash (MAR) prior to developing MAM/Mc. The incidence (n = 5/42, 11.9%) of muscular mogamulizumab-associated irAEs may be higher than has been previously reported in clinical trials and may be of late onset (a median of 5 cycles and as late as 100 days from the last infusion). We highlight the utility of IVIG, together with systemic corticosteroids, for the treatment of these potentially fatal side effects associated with mogamulizumab therapy., (© The Author(s) 2023. Published by Oxford University Press.)
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- 2023
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17. Effects of beetroot juice supplementation on vascular functional and structural changes in aged mice.
- Author
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Tawa M, Nakagawa K, and Ohkita M
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- Mice, Animals, Acetylcholine, Antioxidants, Dietary Supplements, Nitrates, Vascular Diseases
- Abstract
This study investigated whether beetroot juice (BRJ) ingestion ameliorates aging-induced functional and structural changes in vasculature. Aged mice (98-100 weeks old) were supplemented with BRJ (nitrate: 3.5 mmol/L) or drinking water for 4 weeks and compared with young mice (12-15 weeks old). The vasorelaxant response of isolated aortas to acetylcholine was markedly weaker in aged mice than in young mice, but the attenuated relaxation was significantly improved in BRJ-supplemented aged mice. The acetylcholine-induced relaxation was completely abolished by N
ω -nitro-l-arginine methyl ester in all groups. Additionally, the response to sodium nitroprusside was comparable among the three groups. The aortic medial thickness was significantly greater in aged mice than in young mice, and BRJ supplementation did not suppress this thickening. Plasma nitrate levels were significantly higher in BRJ-supplemented aged mice than in non-supplemented aged mice. Conversely, non-supplemented aged mice had high plasma levels of thiobarbituric acid-reactive substances, but the levels were suppressed in BRJ-supplemented aged mice. These findings suggest that BRJ ingestion improves vascular endothelial dysfunction associated with aging, at least in part, by enhancing nitric oxide bioavailability and reducing oxidative stress. Therefore, beetroot ingestion may be a highly useful self-medication option to prevent vascular aging., (© 2023 The Authors. Physiological Reports published by Wiley Periodicals LLC on behalf of The Physiological Society and the American Physiological Society.)- Published
- 2023
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18. Factors influencing the soluble guanylate cyclase heme redox state in blood vessels.
- Author
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Tawa M and Okamura T
- Subjects
- Guanylate Cyclase metabolism, Nitrogen, Oxidation-Reduction, Oxidoreductases metabolism, Oxygen, Soluble Guanylyl Cyclase metabolism, Heme metabolism, Nitric Oxide metabolism
- Abstract
Soluble guanylate cyclase (sGC) plays an important role in maintaining vascular homeostasis, as an acceptor for the biological messenger nitric oxide (NO). However, only reduced sGC (with a ferrous heme) can be activated by NO; oxidized (ferric heme) and apo (absent heme) sGC cannot. In addition, the proportions of reduced, oxidized, and apo sGC change under pathological conditions. Although diseased blood vessels often show decreased NO bioavailability in the vascular wall, a shift of sGC heme redox balance in favor of the oxidized/apo forms can also occur. Therefore, sGC is of growing interest as a drug target for various cardiovascular diseases. Notably, the balance between NO-sensitive reduced sGC and NO-insensitive oxidized/apo sGC in the body is regulated in a reversible manner by various biological molecules and proteins. Many studies have attempted to identify endogenous factors and determinants that influence this redox state. For example, various reactive nitrogen and oxygen species are capable of inducing the oxidation of sGC heme. Conversely, a heme reductase and some antioxidants reduce the ferric heme in sGC to the ferrous state. This review summarizes the factors and mechanisms identified by these studies that operate to regulate the sGC heme redox state., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Inc. All rights reserved.)
- Published
- 2022
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19. IL-32 Supports the Survival of Malignant T Cells in Cutaneous T-cell Lymphoma.
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Yu KK, Smith NP, Essien SV, Teague JE, Vieyra-Garcia P, Gehad A, Zhan Q, Crouch JD, Gerard N, Larocca C, Wolf P, LeBoeuf NR, Tawa M, Kupper TS, Villani AC, and Clark RA
- Subjects
- Humans, T-Lymphocytes pathology, Lymphoma, T-Cell, Cutaneous pathology, Skin Neoplasms pathology
- Published
- 2022
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20. Topical tofacitinib for the management of lymphocytic-variant hypereosinophilic syndrome with cutaneous involvement.
- Author
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Said JT, Elman SA, Tawa M, Fisher DC, Merola JF, and Kupper TS
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- Humans, Piperidines, Pyrimidines, Hypereosinophilic Syndrome diagnosis, Hypereosinophilic Syndrome drug therapy
- Published
- 2022
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21. Vascular Endothelial Dysfunction in the Thoracic Aorta of Rats with Ischemic Acute Kidney Injury: Contribution of Indoxyl Sulfate.
- Author
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Nakagawa K, Tanaka R, Donouchi M, Kanda M, Kamada S, Kobuchi S, Tawa M, Matsumura Y, and Ohkita M
- Subjects
- Animals, Carbon administration & dosage, Disease Models, Animal, Disease Progression, Male, Nitric Oxide metabolism, Oxides administration & dosage, Rats, Rats, Sprague-Dawley, Reactive Oxygen Species metabolism, Recovery of Function drug effects, Renal Insufficiency, Chronic metabolism, Acute Kidney Injury blood, Acute Kidney Injury complications, Aorta, Thoracic metabolism, Endothelial Cells metabolism, Endothelium, Vascular metabolism, Indican blood, Ischemia blood, Ischemia complications, Reperfusion Injury blood, Reperfusion Injury complications, Signal Transduction drug effects
- Abstract
Chronic kidney disease (CKD) and cardiovascular disease are known to be linked, and the involvement of indoxyl sulfate (IS), a type of uremic toxin, has been suggested as one of the causes. It is known that IS induces vascular dysfunction through overproduction of reactive oxygen species (ROS). On the other hand, the involvement of IS in the vascular dysfunction associated with acute kidney injury (AKI) is not fully understood. Therefore, we investigated this issue using the thoracic aorta of rats with ischemic AKI. Ischemic AKI was induced by occlusion of the left renal artery and vein for 45 min, followed by reperfusion 2 weeks after contralateral nephrectomy. One day after reperfusion, there was marked deterioration in renal function evidenced by an increase in plasma creatinine. Furthermore, blood IS levels increased markedly due to worsening renal function. Seven days and 28 days after reperfusion, blood IS levels decreased with the improvement in renal function. Of note, acetylcholine-induced vasorelaxation deteriorated over time after reperfusion, contradicting the recovery of renal function. In addition, 28 days after reperfusion, we observed a significant increase in ROS production in the vascular tissue. Next, we administered AST-120, a spherical adsorbent charcoal, after reperfusion to assess whether the vascular endothelial dysfunction associated with the ischemic AKI was due to a temporary increase in blood IS levels. AST-120 reduced the temporary increase in blood IS levels after reperfusion without influencing renal function, but did not restore the impaired vascular reactivity. Thus, in ischemic AKI, we confirmed that the vascular endothelial function of the thoracic aorta is impaired even after the recovery of kidney injury, probably with excessive ROS production. IS, which increases from ischemia to early after reperfusion, may not be a major contributor to the vascular dysfunction associated with ischemic AKI., Competing Interests: The authors declare that there is no conflict of interest regarding the publication of this paper., (Copyright © 2022 Keisuke Nakagawa et al.)
- Published
- 2022
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22. Acute Kynurenine Exposure of Rat Thoracic Aorta Induces Vascular Dysfunction via Superoxide Anion Production.
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Nakagawa K, Kobayashi F, Kamei Y, Tawa M, and Ohkita M
- Subjects
- Animals, Aorta, Thoracic, Endothelium, Vascular, Rats, Vasodilation, Kynurenine pharmacology, Superoxides
- Abstract
The accumulation of uremic toxins is known to be one of the causes of cardiovascular disorder related to renal disease. Among the many uremic toxins, we focused on kynurenine (kyn), whose levels have been shown to be positively correlated with vascular endothelial dysfunction markers, and directly evaluated the influence of kyn on the rat thoracic aorta. Exposure of the endothelium-intact aorta to kyn markedly attenuated the acetylcholine (ACh)-induced relaxation and significantly increased superoxide anion (O
2 ·- ) production. These effects were ameliorated by pretreatment with ascorbic acid, an antioxidant, and CH223191, an aryl hydrocarbon receptor (AhR) inhibitor, but not by apocynin, a reduced nicotinamide adenine dinucleotide phosphate (NADPH) oxidase inhibitor. In the endothelium-denuded aorta, kyn significantly attenuated the nitric oxide (NO) donor sodium nitroprusside (SNP)-induced vasorelaxation and increased the O2 ·- production. Ascorbic acid treatment significantly ameliorated these effects, whereas CH223191 and apocynin treatments did not. Kyn had no influence on the vasorelaxant response to BAY 41-2272, a soluble guanylate cyclase stimulator. This suggested that kyn attenuates the NO-mediated vasorelaxation response by promoting O2 ·- production in thoracic aorta to inactivate NO. O2 ·- production is likely stimulated in both vascular endothelium and smooth muscle, the former of which may be mediated by AhR activation.- Published
- 2022
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23. Soluble Guanylate Cyclase-Mediated Relaxation in Aortas from Rats with Renovascular Hypertension.
- Author
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Tawa M, Shimosato T, Nakagawa K, Okamura T, and Ohkita M
- Subjects
- Animals, Aorta, Cyclic GMP, Nitric Oxide, Rats, Soluble Guanylyl Cyclase, Guanylate Cyclase, Hypertension, Renovascular
- Abstract
Soluble guanylate cyclase (sGC) plays an important role in nitric oxide (NO)-mediated regulation of vascular tone; however, NO bioavailability is often reduced in diseased blood vessels. Accumulating evidence suggests that a shift of sGC from the NO-sensitive form to the NO-insensitive form could be an underlying cause contributing to this reduction. Herein, we investigated the impact of renovascular hypertension on NO-sensitive and NO-insensitive sGC-mediated relaxation in rat aortas. Renovascular hypertension was induced by partially clipping the left renal artery (2-kidneys, 1-clip; 2K1C) for 10 weeks. Systolic, diastolic, and mean arterial pressures were significantly increased in the 2K1C group when compared with the sham group. In addition, plasma thiobarbituric acid reactive substances and aortic superoxide generation were significantly enhanced in the 2K1C group when compared with those in the sham group. The vasorelaxant response of isolated aortas to the sGC stimulator BAY 41-2272 (NO-sensitive sGC agonist) was comparable between the sham and 2K1C groups. Likewise, the sGC activator BAY 60-2770 (NO-insensitive sGC agonist)-induced relaxation did not differ between the sham and 2K1C groups. In addition, the cGMP mimetic 8-Br-cGMP (protein kinase G agonist) induced similar relaxation in both groups. Furthermore, there were no differences in BAY 41-2272-stimulated and BAY 60-2770-stimulated cGMP generation between the groups. These findings suggest that the balance between NO-sensitive and NO-insensitive forms of sGC is maintained during renovascular hypertension. Therefore, sGC might not be responsible for the reduced NO bioavailability observed during renovascular hypertension., (© 2021 S. Karger AG, Basel.)
- Published
- 2022
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24. Alteration of the soluble guanylate cyclase system in coronary arteries of high cholesterol diet-fed rabbits.
- Author
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Tawa M, Nakano K, Yamashita Y, He Q, Masuoka T, Okamura T, and Ishibashi T
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- Animals, Atherosclerosis metabolism, Atherosclerosis pathology, Atherosclerosis physiopathology, Cholesterol, Dietary blood, Coronary Vessels metabolism, Coronary Vessels pathology, Coronary Vessels physiology, Cyclic GMP metabolism, Male, Rabbits, Cholesterol, Dietary administration & dosage, Coronary Vessels drug effects, Soluble Guanylyl Cyclase metabolism
- Abstract
This study aimed to investigate how atherosclerosis affects the soluble guanylate cyclase (sGC) system in coronary arteries. Rabbits were fed a normal diet for 12 weeks (N group) or a diet containing high cholesterol (1%) for 4 weeks (S-HC group) and 12 weeks (L-HC group). Cholesterol deposition in the intima of coronary arteries was observed in the S-HC group, but the formation of an atherosclerotic plaque was not observed. In contrast, a major plaque developed in the L-HC group. The relaxant response of isolated coronary arteries to sodium nitroprusside (SNP, nitric oxide donor) was not different between the N and S-HC groups, whereas the response in the L-HC group was markedly attenuated. The relaxation induced by BAY 60-2770 (sGC activator) tended to be augmented in the S-HC group, but it was significantly impaired in the L-HC group compared to that in the N group. sGC β1 immunostaining was equally detected in the medial layer of the arteries among the N, S-HC, and L-HC groups. In addition, a strong staining was observed in the plaque region of the L-HC group. cGMP levels in the arteries stimulated with SNP were identical in the N and S-HC groups and slightly lower in the L-HC group than the other groups. BAY 60-2770-stimulated cGMP formation tended to be increased in the S-HC and L-HC groups. These findings suggest that the sGC system was not normal in atherosclerotic coronary arteries. The redox state of sGC and the distribution pattern are likely to change with the progression of atherosclerosis., (© 2021 The Authors. Pharmacology Research & Perspectives published by British Pharmacological Society and American Society for Pharmacology and Experimental Therapeutics and John Wiley & Sons Ltd.)
- Published
- 2021
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25. Preventive effects of nitrate-rich beetroot juice supplementation on monocrotaline-induced pulmonary hypertension in rats.
- Author
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Tawa M, Nagata R, Sumi Y, Nakagawa K, Sawano T, Ohkita M, and Matsumura Y
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- Animals, Blood Pressure, Dietary Supplements, Hypertension, Pulmonary etiology, Male, Monocrotaline toxicity, Nitrates analysis, Rats, Rats, Sprague-Dawley, Beta vulgaris chemistry, Fruit and Vegetable Juices, Hypertension, Pulmonary prevention & control
- Abstract
Beetroot (Beta vulgaris L.) has a high level of nitrate; therefore, its dietary intake could increase nitric oxide (NO) level in the body, possibly preventing the development of pulmonary hypertension (PH). In this study, we examined the effects of beetroot juice (BJ) supplementation on PH and the contribution of nitrate to such effects using a rat model of monocrotaline (MCT, 60 mg/kg s.c.)-induced PH. Rats were injected subcutaneously with saline or 60 mg/kg MCT and were sacrificed 28 days after the injection. In some rats injected with MCT, BJ was supplemented from the day of MCT injection to the day of sacrifice. First, MCT-induced right ventricular systolic pressure elevation, pulmonary arterial medial thickening and muscularization, and right ventricular hypertrophy were suppressed by supplementation with low-dose BJ (nitrate: 1.3 mmol/L) but not high-dose BJ (nitrate: 4.3 mmol/L). Of the plasma nitrite, nitrate, and their sum (NOx) levels, only the nitrate levels were found to be increased by the high-dose BJ supplementation. Second, in order to clarify the possible involvement of nitrate in the preventive effects of BJ on PH symptoms, the effects of nitrate-rich BJ (nitrate: 0.9 mmol/L) supplementation were compared with those of the nitrate-depleted BJ. While the former exerted preventive effects on PH symptoms, such effects were not observed in rats supplemented with nitrate-depleted BJ. Neither supplementation with nitrate-rich nor nitrate-depleted BJ affected plasma nitrite, nitrate, and NOx levels. These findings suggest that a suitable amount of BJ ingestion, which does not affect systemic NO levels, can prevent the development of PH in a nitrate-dependent manner. Therefore, BJ could be highly useful as a therapy in patients with PH., Competing Interests: The authors have declared that no competing interests exist.
- Published
- 2021
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26. Indoxyl sulfate induces ROS production via the aryl hydrocarbon receptor-NADPH oxidase pathway and inactivates NO in vascular tissues.
- Author
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Nakagawa K, Itoya M, Takemoto N, Matsuura Y, Tawa M, Matsumura Y, and Ohkita M
- Subjects
- Acetylcholine pharmacology, Animals, Basic Helix-Loop-Helix Transcription Factors metabolism, Endothelium, Vascular metabolism, Male, Nitroprusside pharmacology, Rats, Rats, Sprague-Dawley, Receptors, Aryl Hydrocarbon metabolism, Superoxides metabolism, Vasodilator Agents pharmacology, Aorta, Thoracic metabolism, Indican metabolism, NADPH Oxidases metabolism, Nitric Oxide metabolism, Reactive Oxygen Species metabolism
- Abstract
Aims: The uremic toxin indoxyl sulfate (IS) was reported to be the cause of cardiovascular disease associated with chronic kidney disease. Therefore, we evaluated the direct influences of IS on vascular function, focusing on the superoxide anion (O
2 - ) and nitric oxide (NO)/soluble guanylate cyclase (sGC) pathways., Main Methods: Isolated rat thoracic aortas with and without vascular endothelium were incubated with IS for 4 h in a physiological solution. In some experiments, several inhibitors were treated 30 min before the addition of IS. O2 - production was measured by the chemiluminescence method, and the vascular reactivity to different vasorelaxants was examined using organ chamber technique., Key Findings: 1) Experiments using endothelium-intact vascular rings: IS significantly increased O2 - production. The increase was suppressed by addition of the NADPH oxidase inhibitor apocynin, the antioxidant ascorbic acid and the aryl hydrocarbon receptor (AhR) inhibitor CH223191. Furthermore, IS attenuated the acetylcholine (ACh)-induced vasorelaxantion, which was suppressed by addition of the above drugs. 2) Experiments using endothelium-denuded vascular rings: IS significantly increased O2 - production and also attenuated sodium nitroprusside (SNP)-induced vasorelaxation. These influences of IS were normalized only by ascorbic acid addition. On the other hand, IS did not affect the vasorelaxation by the sGC stimulator BAY 41-2272., Significance: This study suggested that IS causes O2 - production in vascular tissues, thereby attenuating ACh- and SNP-induced vasorelaxation, probably through NO inactivation. Furthermore, it is reasonable to consider that IS-promoted O2 - production in the presence of vascular endothelium is through binding to AhR and the activation of NADPH oxidase., (Copyright © 2020 Elsevier Inc. All rights reserved.)- Published
- 2021
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27. Chronic Tear Deficiency Sensitizes Transient Receptor Potential Vanilloid 1-Mediated Responses in Corneal Sensory Nerves.
- Author
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Masuoka T, Yamashita Y, Nakano K, Takechi K, Niimura T, Tawa M, He Q, Ishizawa K, and Ishibashi T
- Abstract
Chronic tear deficiency enhances the excitability of corneal cold-sensitive nerves that detect ocular dryness, which can lead to discomfort in patients with dry eye disease (DED). However, changes in corneal nerve excitations through the polymodal nociceptor "transient receptor potential vanilloid 1" (TRPV1) and the potential link between this receptor and symptoms of DED remain unclear. In this study, we examined the firing properties of corneal cold-sensitive nerves expressing TRPV1 and possible contributions of chronic tear deficiency to corneal nerve excitability by TRPV1 activation. The bilateral excision of lacrimal glands in guinea pigs decreased the tear volume and increased the frequency of spontaneous eyeblinks 1-4 weeks after surgery. An analysis of the firing properties of the cold-sensitive nerves was performed by single-unit recordings of corneal preparations 4 weeks after surgery in both the sham-operated and gland-excised groups. Perfusion of the TRPV1 agonist, capsaicin (1 μM), transiently increased the firing frequency in approximately 46-48% of the cold-sensitive nerves characterized by low-background activity and high threshold (LB-HT) cold thermoreceptors in both groups. Gland excision significantly decreased the latency of capsaicin-induced firing in cold-sensitive nerves; however, its magnitude was unchanged. Calcium imaging of cultured trigeminal ganglion neurons from both groups showed that intracellular calcium elevation of corneal neurons induced by a low concentration of capsaicin (0.03 μM) was significantly larger in the gland excision group, regardless of responsiveness to cold. An immunohistochemical study of the trigeminal ganglion revealed that gland excision significantly increased the proportion of corneal neurons enclosed by glial fibrillary acidic protein (GFAP)-immunopositive satellite glial cells. Topical application of the TRPV1 antagonist, A784168 (30 μM), on the ocular surface attenuated eye-blink frequency after gland excision. Furthermore, gland excision enhanced blink behavior induced by a low concentration of capsaicin (0.1 μM). These results suggest that chronic tear deficiency sensitizes the TRPV1-mediated response in the corneal LB-HT cold thermoreceptors and cold-insensitive polymodal nociceptors, which may be linked to dry eye discomfort and hyperalgesia resulting from nociceptive stimuli in aqueous-deficient dry eyes., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2020 Masuoka, Yamashita, Nakano, Takechi, Niimura, Tawa, He, Ishizawa and Ishibashi.)
- Published
- 2020
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28. Sensitization of glutamate receptor-mediated pain behaviour via nerve growth factor-dependent phosphorylation of transient receptor potential V1 under inflammatory conditions.
- Author
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Masuoka T, Yamashita Y, Yoshida J, Nakano K, Tawa M, Nishio M, and Ishibashi T
- Subjects
- A Kinase Anchor Proteins, Animals, Ganglia, Spinal metabolism, Male, Mice, Mice, Inbred C57BL, Phosphorylation, Nerve Growth Factor metabolism, Pain drug therapy, TRPV Cation Channels metabolism
- Abstract
Background and Purpose: Glutamate and metabotropic glutamate (mGlu) receptors on primary sensory neurons are crucial in modulating pain sensitivity. However, it is unclear how inflammation affects mGlu receptor-mediated nociceptive responses. We therefore investigated the effects of mGlu
1/5 receptor agonists on pain-related behaviour during persistent inflammation and their underlying mechanisms., Experimental Approach: Effects of a mGlu1/5 receptor agonist on pain-related behaviour during inflammation was assessed in mice. Intracellular calcium responses, membrane current responses, and protein expression in primary sensory neurons were examined using cultured dorsal root ganglion (DRG) neurons, dissociated from wild-type and gene knockout mice., Key Results: Persistent inflammation induced by complete Freund's adjuvant increased the duration of mGlu1/5 receptor-mediated pain behaviour, which was antagonized by inhibition of nerve growth factor (NGF)-tropomyosin receptor kinase A (TrkA) signalling. Calcium imaging revealed that NGF treatment increased the number of cultured DRG neurons responding to mGlu1/5 receptor activation. Stimulation of mGlu1/5 receptors in NGF-treated DRG neurons induced inward currents through TRPV1 channels in association with PLC but not with IP3 receptors. NGF treatment also increased the number of neurons responding to a DAG analogue via TRPV1 channel activation. Furthermore, NGF up-regulated expression of TRPV1 and A-kinase anchoring protein 5 (AKAP5), resulting in increased AKAP5-dependent TRPV1 phosphorylation. AKAP5 knockout mice did not exhibit mGlu1/5 receptor-mediated excitation in NGF-treated DRG neurons or pain response facilitation under inflammatory conditions., Conclusions and Implications: NGF augments glutamate- and mGlu1/5 receptor-mediated excitation of nociceptive neurons by AKAP5-dependent phosphorylation of TRPV1 channels, potentiating hypersensitivity to glutamate in inflamed tissues., (© 2020 The British Pharmacological Society.)- Published
- 2020
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29. Effect of Betanin, a Beetroot Component, on Vascular Tone in Isolated Porcine Arteries.
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Tawa M, Masuoka T, Yamashita Y, Nakano K, and Ishibashi T
- Subjects
- Animals, Female, Male, Plant Roots, Sus scrofa, Beta vulgaris, Betacyanins pharmacology, Coronary Vessels drug effects, Mesenteric Arteries drug effects, Pulmonary Artery drug effects
- Abstract
Background: Beetroot has attracted much attention because of its blood pressure-lowering properties. Although beetroot contains various nutritional compounds, including inorganic nitrate, some of their physiological properties are not fully understood. In this study, we examined whether betanin, a beetroot component, has a regulatory effect on vascular tone., Methods: Mechanical responses of isolated porcine coronary, mesenteric, and pulmonary arteries were assessed by organ chamber technique. In some cases, the vascular reactivity was observed in the presence of a physiological concentration of betanin (10 µM)., Results: Betanin did not induce vasorelaxation at physiological concentrations both in endothelium-intact and -denuded coronary, mesenteric, and pulmonary arteries. The endothelium-dependent agonists, bradykinin and A23187 induced vasorelaxation of endothelium-intact coronary arteries, both of which were not affected by exposure to betanin. Likewise, endothelium-independent vasorelaxation induced by sodium nitrite and sodium nitroprusside was also not affected by the presence of betanin. In addition, exposure of endothelium-intact coronary arteries to betanin did not attenuate prostaglandin F2α- and endothelin-1-induced vasocontraction., Conclusions: These findings suggest that betanin does not have a vasorelaxant activity. It is unlikely that betanin is a component directly responsible for the beetroot-induced acute blood pressure-lowering effect in a nitrate-independent manner., (© American Journal of Hypertension, Ltd 2020. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)
- Published
- 2020
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30. Impact of cigarette smoking on nitric oxide-sensitive and nitric oxide-insensitive soluble guanylate cyclase-mediated vascular tone regulation.
- Author
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Tawa M, Kinoshita T, Masuoka T, Yamashita Y, Nakano K, Nishio M, Okamura T, and Ishibashi T
- Subjects
- Acetylcholine pharmacology, Adult, Animals, Aorta drug effects, Female, Gastroepiploic Artery drug effects, Humans, Male, Middle Aged, Nitric Oxide Donors pharmacology, Nitroprusside pharmacology, Pulmonary Artery drug effects, Rats, Reactive Oxygen Species blood, Thiobarbituric Acid Reactive Substances metabolism, Vasodilation physiology, Young Adult, Cigarette Smoking physiopathology, Gastroepiploic Artery physiopathology, Nitric Oxide physiology, Pulmonary Artery physiopathology, Soluble Guanylyl Cyclase physiology, Vasodilation drug effects
- Abstract
Cigarette smoking induces vascular endothelial dysfunction characterized by impaired nitric oxide (NO) bioavailability. There are two types of soluble guanylate cyclase (sGC), which is a cellular target of NO: NO-sensitive reduced form (the heme moiety with a ferrous iron) and NO-insensitive oxidized (the heme moiety with a ferric iron)/heme-free form. This study investigated the influence of cigarette smoking on NO-sensitive and NO-insensitive sGC-mediated vascular tone regulation in organ chamber experiments with isolated rat and human arteries. The rats were subcutaneously administered phosphate-buffered saline (PBS), nicotine-free cigarette smoke extract (N(-)-CSE) or nicotine-containing cigarette smoke extract (N(+)-CSE) for 4 weeks. Plasma thiobarbituric acid reactive substance (TBARS) levels were higher in the N(+)-CSE group than those in the N(-)-CSE group, and TBARS levels for these groups were higher than those for the PBS group. In the aorta and the pulmonary artery in rats administered N(-)-CSE or N(+)-CSE, acetylcholine-induced relaxation was significantly impaired compared with that in rats administered PBS; there was no significant difference in the relaxation between the N(-)-CSE and N(+)-CSE groups. However, sodium nitroprusside (NO-sensitive sGC stimulant)- and BAY 60-2770 (NO-insensitive sGC stimulant)-induced relaxations were not different among the three groups, regardless of the vessel type. In addition, in the human gastroepiploic artery, the relaxant responses to these sGC-targeting drugs were identical between nonsmokers and smokers. These findings suggest that NO-sensitive and NO-insensitive sGC-mediated vascular tone regulation functions normally even in blood vessels damaged by cigarette smoking.
- Published
- 2020
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31. Improving the Gastrointestinal Tolerability of Fumaric Acid Esters: Early Findings on Gastrointestinal Events with Diroximel Fumarate in Patients with Relapsing-Remitting Multiple Sclerosis from the Phase 3, Open-Label EVOLVE-MS-1 Study.
- Author
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Palte MJ, Wehr A, Tawa M, Perkin K, Leigh-Pemberton R, Hanna J, Miller C, and Penner N
- Subjects
- Adult, Dimethyl Fumarate therapeutic use, Female, Fumarates therapeutic use, Humans, Immunosuppressive Agents therapeutic use, Male, Middle Aged, Dimethyl Fumarate adverse effects, Drug-Related Side Effects and Adverse Reactions, Fumarates adverse effects, Gastrointestinal Diseases chemically induced, Gastrointestinal Diseases therapy, Immunosuppressive Agents adverse effects, Multiple Sclerosis, Relapsing-Remitting drug therapy
- Abstract
Introduction: Diroximel fumarate (DRF) is a novel oral fumarate in development for patients with relapsing forms of multiple sclerosis (MS). Clinical findings from the DRF development program suggest that rates of gastrointestinal (GI) treatment-emergent adverse events (TEAEs) and discontinuation due to GI TEAEs are low, based on clinical and real-world observations of other fumaric acid esters, including dimethyl fumarate (DMF). The incidence of GI TEAEs varies from 40 to 88% in clinical and real-world studies of DMF. The objective of this study is to present GI tolerability findings from the EVOLVE-MS-1 study and present biologic hypotheses for the improved GI properties of DRF., Methods: GI TEAEs and treatment discontinuation because of GI TEAEs were assessed in DRF-treated patients with relapsing-remitting MS who were participating in the ongoing, 96-week, open-label, phase 3 EVOLVE-MS-1 study., Results: As of March 30, 2018, a total of 696 patients were enrolled in EVOLVE-MS-1. GI TEAEs were reported in 30.9% (215/696) of patients; the vast majority (96%; 207/215) experienced events that were mild or moderate in severity. When GI AEs did occur, they occurred early in treatment, resolved (88.8%; 191/215), and were of short duration [median 7.5 (range 1-87) days] in most patients. GI TEAEs led to < 1% of patients discontinuing treatment., Conclusions: We suggest that the distinct chemical structure of DRF contributes to the observed low rates of GI TEAEs and GI-associated treatment discontinuations, possibly due to a combination of several factors. We hypothesize that these factors may include less reactivity with off-target proteins and/or lower production of a methanol leaving group that may contribute to GI irritation. A direct comparison of GI tolerability with DRF versus DMF is being evaluated in the EVOLVE-MS-2 study., Trial Registration: ClinicalTrials.gov number NCT02634307., Funding: Alkermes Inc. (Waltham, MA, USA) and Biogen (Cambridge, MA, USA).
- Published
- 2019
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32. Cutaneous T-Cell Lymphoma: Optimizing Care in Patients Receiving Anti-CCR4 Monoclonal Antibody Mogamulizumab.
- Author
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Tawa M, Kopp E, McCann S, and Cantrell W
- Subjects
- Antibodies, Monoclonal, Humanized adverse effects, Antibodies, Monoclonal, Humanized immunology, Humans, Lymphoma, T-Cell, Cutaneous diagnosis, Lymphoma, T-Cell, Cutaneous pathology, Neoplasm Staging, Skin Neoplasms diagnosis, Skin Neoplasms pathology, Antibodies, Monoclonal, Humanized therapeutic use, Lymphoma, T-Cell, Cutaneous drug therapy, Receptors, CCR4 immunology, Skin Neoplasms drug therapy
- Abstract
Background: Cutaneous T-cell lymphoma (CTCL), including subtypes mycosis fungoides (MF) and Sézary syndrome (SS), represents a rare group of non-Hodgkin lymphomas. Mogamulizumab is a first-in-class monoclonal antibody that selectively binds to C-C chemokine receptor 4, which is overexpressed on the surface of tumor cells in T-cell malignancies, including MF/SS-type CTCL., Objectives: This review identifies common diagnostic features of MF/SS, the efficacy and side effect profile of mogamulizumab, and practical management strategies for optimizing the nursing care of patients with MF/SS-type CTCL., Methods: Case studies are used to describe the role of mogamulizumab in CTCL and to review practical considerations when administering mogamulizumab to patients., Findings: Mogamulizumab is an effective treatment for adult patients with relapsed or refractory MF/SS-type CTCL who have received at least one prior systemic therapy. Infusion reactions and drug eruptions require prompt diagnosis and treatment.
- Published
- 2019
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33. Responsiveness of rat aorta and pulmonary artery to cGMP generators in the presence of thiol or heme oxidant.
- Author
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Tawa M, Yamashita Y, Masuoka T, Nakano K, Yoshida J, Nishio M, and Ishibashi T
- Subjects
- Animals, Dithiothreitol pharmacology, In Vitro Techniques, Male, Oxidative Stress, Rats, Wistar, Soluble Guanylyl Cyclase metabolism, Aorta drug effects, Benzoates pharmacology, Biphenyl Compounds pharmacology, Cyclic GMP metabolism, Diamide pharmacology, Hydrocarbons, Fluorinated pharmacology, Nitric Oxide Donors pharmacology, Nitroprusside pharmacology, Oxidants pharmacology, Pulmonary Artery drug effects, Pyrazoles pharmacology, Pyridines pharmacology, Sulfhydryl Compounds pharmacology, Vasodilation drug effects, Vasodilator Agents pharmacology
- Abstract
This study investigated the effects of thiol and heme oxidants on responsiveness to cGMP generators in isolated rat aorta and pulmonary artery using an organ chamber. The nitric oxide (NO) donor sodium nitroprusside (SNP)-induced relaxation was impaired by exposure to the thiol oxidant diamide in both the aorta and the pulmonary artery, whereas the soluble guanylate cyclase (sGC) stimulator BAY 41-2272- or the sGC activator BAY 60-2770-induced relaxation was not affected. The impairment by diamide of SNP-induced aortic and pulmonary arterial relaxation was completely restored by post-treatment with the thiol reductant dithiothreitol. However, regardless of the vessel type, the relaxant response to SNP or BAY 41-2272 was impaired by exposure to the heme oxidant ODQ, whereas the response to BAY 60-2770 was enhanced. The ODQ-induced effects were reversed partially by post-treatment with the heme reductant dithionite. These findings indicate that thiol oxidation attenuates only the vascular responsiveness to NO donors and that heme oxidation attenuates the responsiveness to NO donors and sGC stimulators but augments that to sGC activators. Therefore, under oxidative stress, the order of usability of the vasodilators is suggested to be: NO donors < sGC stimulators < sGC activators., (Copyright © 2019 The Authors. Production and hosting by Elsevier B.V. All rights reserved.)
- Published
- 2019
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34. Effects of Beet Juice Supplementation on Monocrotaline-Induced Pulmonary Hypertension in Rats.
- Author
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Tawa M, Yano Y, Yamanaka M, Sawano T, Iesaki K, Murata Y, Tanaka R, Nakagawa K, Ohkita M, and Matsumura Y
- Subjects
- Animals, Disease Models, Animal, Hypertrophy, Right Ventricular chemically induced, Hypertrophy, Right Ventricular physiopathology, Hypertrophy, Right Ventricular prevention & control, Male, Monocrotaline, Nitric Oxide metabolism, Plant Roots, Pulmonary Arterial Hypertension chemically induced, Pulmonary Arterial Hypertension metabolism, Pulmonary Arterial Hypertension physiopathology, Pulmonary Artery metabolism, Rats, Sprague-Dawley, Vascular Remodeling, Ventricular Dysfunction, Right chemically induced, Ventricular Dysfunction, Right physiopathology, Ventricular Dysfunction, Right prevention & control, Ventricular Function, Right, Arterial Pressure, Beta vulgaris, Dietary Supplements, Fruit and Vegetable Juices, Pulmonary Arterial Hypertension prevention & control, Pulmonary Artery physiopathology
- Abstract
Background: Recently, attention has been focused on the cardiovascular protective effects of beet juice (BJ) with high amounts of nitrate. In this study, we examined the effect of BJ supplementation in a rat model of monocrotaline (MCT)-induced pulmonary hypertension (PH)., Methods: MCT (60 mg/kg) was subcutaneously administered to rats, and BJ (prepared by dissolving BJ powder at a concentration of 1 g/l or 10 g/l in drinking water) supplementation was started from the day of, 1 week before, and 2 weeks after MCT injection. Saline-injected rats given drinking water were used as controls., Results: Low-dose BJ supplementation starting from the day of MCT injection exerted protective effects on the MCT-induced elevation of right ventricular systolic pressure, right ventricular hypertrophy, and pulmonary arterial remodeling, without causing a significant increase in plasma nitrite plus nitrate (NOx) levels. On the other hand, such beneficial effects were not observed with high-dose BJ supplementation, although the NOx levels were slightly higher than those in the low-dose group. In addition, low-dose BJ supplementation starting from 1 week before MCT injection did not improve PH symptoms, as described above. Furthermore, low-dose BJ supplementation starting from 2 weeks after MCT injection was ineffective against functional and morphological alterations in pulmonary circulation associated with MCT-induced PH., Conclusions: Habitual ingestion of a suitable amount of BJ could be a potential option for preventing PH. However, beneficial effects cannot be expected when PH has developed to some degree.
- Published
- 2019
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35. Chronological Change of Vascular Reactivity to cGMP Generators in the Balloon-Injured Rat Carotid Artery.
- Author
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Tawa M, Shimosato T, Sakonjo H, Masuoka T, Nishio M, Ishibashi T, and Okamura T
- Subjects
- Angioplasty, Balloon, Animals, Carotid Arteries drug effects, Carotid Arteries enzymology, Carotid Arteries pathology, Carotid Artery Injuries enzymology, Carotid Artery Injuries pathology, Disease Models, Animal, Enzyme Activation, Male, Muscle, Smooth, Vascular enzymology, Muscle, Smooth, Vascular pathology, Rats, Sprague-Dawley, Second Messenger Systems, Time Factors, Benzoates pharmacology, Biphenyl Compounds pharmacology, Carotid Artery Injuries drug therapy, Cyclic GMP metabolism, Enzyme Activators pharmacology, Hydrocarbons, Fluorinated pharmacology, Muscle, Smooth, Vascular drug effects, Nitric Oxide Donors pharmacology, Sodium Nitrite pharmacology, Soluble Guanylyl Cyclase metabolism, Vasodilation drug effects
- Abstract
Background/aims: Soluble guanylate cyclase (sGC) exists as reduced, oxidized, and heme-free forms. Currently, it is unclear whether endovascular mechanical stenosis has an impact on vascular tone control by drugs targeting sGC, namely cGMP generators., Methods: Pharmacological responses to acidified sodium nitrite (reduced sGC stimulant) and BAY 60-2770 (oxidized/heme-free sGC stimulant) were studied in balloon-injured rat carotid arteries at several time points. In addition, sGC expression was detected by immunohistochemistry., Results: At 1 day after injury, acidified sodium nitrite-induced relaxation was attenuated in the injured artery, whereas BAY 60-2770-induced relaxation was augmented. Similar attenuation of response to acidified sodium nitrite was seen at 7 and 14 days after injury. On the other hand, the augmentation of response to BAY 60-2770 disappeared at 7 and 14 days after injury. At 1 day after injury, the immunohistochemical expression pattern of sGC in the smooth muscle layer of the injured artery was not different from that of the uninjured artery. However, in the injured artery, the intensity of sGC staining was weak at 7 and 14 days after injury., Conclusion: Balloon injury alters vascular responsiveness to cGMP generators, which seems to be associated with the form and/or expression of sGC., (© 2019 S. Karger AG, Basel.)
- Published
- 2019
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36. Involvement of γ-Glutamyl Transpeptidase in Ischemia/Reperfusion-Induced Cardiac Dysfunction in Isolated Rat Hearts.
- Author
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Koyama T, Tsubota A, Sawano T, Tawa M, Watanabe B, Hiratake J, Nakagawa K, Matsumura Y, and Ohkita M
- Subjects
- Animals, Heart physiopathology, Male, Malondialdehyde metabolism, Myocardial Reperfusion Injury physiopathology, Myocardium metabolism, Norepinephrine metabolism, Rats, Rats, Sprague-Dawley, Superoxides metabolism, gamma-Glutamyltransferase metabolism, Aminobutyrates pharmacology, Myocardial Ischemia physiopathology, Organophosphonates pharmacology, gamma-Glutamyltransferase antagonists & inhibitors, gamma-Glutamyltransferase physiology
- Abstract
GGsTop is a highly potent and specific, and irreversible γ-glutamyl transpeptidase (GGT) inhibitor without any influence on glutamine amidotransferases. The aim of the present study was to investigate the involvement of GGT in ischemia/reperfusion-induced cardiac dysfunction by assessing the effects of a treatment with GGsTop. Using a Langendorff apparatus, excised rat hearts underwent 40 min of global ischemia without irrigation and then 30 min of reperfusion. GGT activity was markedly increased in cardiac tissues exposed to ischemia, and was inhibited by the treatment with GGsTop. Exacerbation of cardiac functional parameters caused by ischemia and reperfusion, namely the reduction of left ventricular (LV) developed pressure and the maximum and negative minimum values of the first derivative of LV pressure, and the increment in LV end-diastolic pressure was significantly attenuated by GGsTop treatment. The treatment with GGsTop suppressed excessive norepinephrine release in the coronary perfusate, a marker for myocardial dysfunction, after ischemia/reperfusion. In addition, oxidative stress indicators in myocardium, including superoxide and malondialdehyde, after ischemia/reperfusion were significantly low in the presence of GGsTop. These observations demonstrate that enhanced GGT activity contributes to cardiac damage after myocardial ischemia/reperfusion, possibly via increased oxidative stress and subsequent norepinephrine overflow. GGT inhibitors have potential as a therapeutic strategy to prevent myocardial ischemia/reperfusion injury in vivo.
- Published
- 2019
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37. Stimulation of nitric oxide-sensitive soluble guanylate cyclase in monocrotaline-induced pulmonary hypertensive rats.
- Author
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Tawa M, Furukawa T, Tongu H, Sugihara M, Taguwa S, Yamanaka M, Yano Y, Matsumori H, Kitada R, Sawano T, Tanaka R, Ohkita M, and Matsumura Y
- Subjects
- Animals, Hypertension, Pulmonary chemically induced, Hypertension, Pulmonary drug therapy, Hypertension, Pulmonary pathology, Male, Pulmonary Artery drug effects, Rats, Rats, Sprague-Dawley, Blood Pressure drug effects, Bronchodilator Agents pharmacology, Hypertension, Pulmonary enzymology, Monocrotaline toxicity, Nitric Oxide pharmacology, Pulmonary Artery enzymology, Soluble Guanylyl Cyclase metabolism
- Abstract
Aims: In this study, we examined whether a disruption in the balance between nitric oxide (NO)-sensitive and -insensitive soluble guanylate cyclase (sGC) is observed in pulmonary hypertension (PH) and whether treatment with NO-enhancing drugs can halt disease progression., Main Methods: Rats were injected subcutaneously with saline or 60 mg/kg monocrotaline (MCT). At 14 days after injection, the vascular reactivity of isolated extralobar pulmonary arteries was assessed by organ chamber technique. In a separate experiment, isosorbide mononitrate (0.3 or 1 g/L) or sodium nitrite (30 or 300 mg/L) was administered in drinking water for the last 14 days (from day 15 to day 28), and their therapeutic potential was evaluated., Key Findings: The NO-sensitive sGC stimulant BAY 41-2272 and the NO-insensitive sGC stimulant BAY 60-2770 both relaxed the pulmonary arteries, which was comparable between saline- and MCT-injected rats. Treatment with isosorbide mononitrate suppressed the MCT-induced right ventricular systolic pressure (RVSP) elevation and pulmonary arterial medial thickening but not right ventricular hypertrophy. However, the beneficial effects on RVSP and pulmonary vascular remodeling were not observed when a high dose was administered. The same results were obtained following the sodium nitrite treatment. Interestingly, NO-enhancing drugs did not increase plasma nitrite plus nitrate levels at a dose that provided the greatest therapeutic advantage., Significance: These findings suggest that the balance between NO-sensitive and -insensitive sGC is not disrupted in the early stage of MCT-induced PH. Furthermore, supplementation with an adequate amount of NO may be a useful therapy to prevent the progression of PH., (Copyright © 2018 Elsevier Inc. All rights reserved.)
- Published
- 2018
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38. Responsiveness of internal thoracic arteries to nitroglycerin in patients with renal failure.
- Author
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Tawa M, Kinoshita T, Asai T, Suzuki T, Ishibashi T, and Okamura T
- Subjects
- Aged, Coronary Artery Disease complications, Coronary Artery Disease physiopathology, Female, Glomerular Filtration Rate, Humans, Intraoperative Period, Male, Mammary Arteries drug effects, Renal Insufficiency physiopathology, Vasodilator Agents pharmacology, Coronary Artery Bypass, Coronary Artery Disease surgery, Mammary Arteries physiopathology, Nitroglycerin pharmacology, Renal Insufficiency complications, Vasodilation drug effects
- Abstract
Nitroglycerin is commonly used as an antispasmodic for treating spasm of coronary artery bypass grafts. This study investigated whether the presence of renal failure affects reactivity to nitroglycerin in internal thoracic arteries obtained from patients undergoing coronary bypass surgery. The patients were divided into three groups according to estimated glomerular filtration rate (eGFR, mL/min/1.73 m
2 ): without renal failure (60 ≤ eGFR, n = 13), with moderate renal failure (30 ≤ eGFR < 60, n = 10), and with severe renal failure (eGFR < 30, n = 10). Organ chamber technique was used to evaluate concentration-related responses of isolated internal thoracic arteries to vasodilators. Nitroglycerin induced a concentration-dependent relaxation, which was significantly augmented in patients with severe but not moderate renal failure than in those without renal failure. In addition, there was a negative correlation between eGFR and the relaxant efficacy of nitroglycerin (P = 0.016). On the other hand, relaxant responses to BAY 60-2770 (which enhances cGMP generation as with nitroglycerin) were similar among three grades of renal function. An inverse relationship of eGFR to the relaxant efficacy of BAY 60-2770 was not observed, either (P = 0.314). These findings suggest that severe renal failure specifically potentiates nitroglycerin-induced relaxation in internal thoracic artery grafts.- Published
- 2018
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39. High-throughput sequencing of the T cell receptor β gene identifies aggressive early-stage mycosis fungoides.
- Author
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de Masson A, O'Malley JT, Elco CP, Garcia SS, Divito SJ, Lowry EL, Tawa M, Fisher DC, Devlin PM, Teague JE, Leboeuf NR, Kirsch IR, Robins H, Clark RA, and Kupper TS
- Subjects
- Cellular Microenvironment, Clone Cells, Exome genetics, Female, Gene Expression Regulation, Neoplastic, Humans, Lymphoma, T-Cell, Cutaneous genetics, Lymphoma, T-Cell, Cutaneous immunology, Lymphoma, T-Cell, Cutaneous pathology, Male, Middle Aged, Multivariate Analysis, Mycosis Fungoides pathology, Prognosis, Progression-Free Survival, Skin pathology, Skin Neoplasms pathology, Genes, T-Cell Receptor beta, High-Throughput Nucleotide Sequencing methods, Mycosis Fungoides genetics, Mycosis Fungoides immunology, Skin Neoplasms genetics, Skin Neoplasms immunology
- Abstract
Mycosis fungoides (MF), the most common cutaneous T cell lymphoma (CTCL) is a malignancy of skin-tropic memory T cells. Most MF cases present as early stage (stage I A/B, limited to the skin), and these patients typically have a chronic, indolent clinical course. However, a small subset of early-stage cases develop progressive and fatal disease. Because outcomes can be so different, early identification of this high-risk population is an urgent unmet clinical need. We evaluated the use of next-generation high-throughput DNA sequencing of the T cell receptor β gene ( TCRB ) in lesional skin biopsies to predict progression and survival in a discovery cohort of 208 patients with CTCL (177 with MF) from a 15-year longitudinal observational clinical study. We compared these data to the results in an independent validation cohort of 101 CTCL patients (87 with MF). The tumor clone frequency (TCF) in lesional skin, measured by high-throughput sequencing of the TCRB gene, was an independent prognostic factor of both progression-free and overall survival in patients with CTCL and MF in particular. In early-stage patients, a TCF of >25% in the skin was a stronger predictor of progression than any other established prognostic factor (stage IB versus IA, presence of plaques, high blood lactate dehydrogenase concentration, large-cell transformation, or age). The TCF therefore may accurately predict disease progression in early-stage MF. Early identification of patients at high risk for progression could help identify candidates who may benefit from allogeneic hematopoietic stem cell transplantation before their disease becomes treatment-refractory., (Copyright © 2018 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.)
- Published
- 2018
- Full Text
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40. Segmental Difference in Vasoreactivity of the Human Right Gastroepiploic Artery.
- Author
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Kinoshita T, Tawa M, Suzuki T, Asai T, and Okamura T
- Subjects
- Dinoprost pharmacology, Dose-Response Relationship, Drug, Endothelin-1 pharmacology, Humans, Phenylephrine pharmacology, Vasoconstriction physiology, Gastroepiploic Artery physiology, Vasoconstriction drug effects, Vasoconstrictor Agents pharmacology
- Abstract
Background: The gastroepiploic artery (GEA) plays an important role in the era of multiple arterial revascularization, but spasm is a major matter of concern. The internal thoracic artery has been shown to have a strong tendency to spasm in its distal bifurcating part, whereas the segmental difference in vasoreactivity of the GEA has never been performed.Methods and Results:The full length of the GEA obtained from 21 patients undergoing a total gastrectomy was divided into 3 sections: proximal (5 cm from the origin), middle, and distal (5 cm from the end). Concentration-response curves for vasoconstrictors (phenylephrine, prostaglandin F2α, and endothelin-1) and vasodilators (carperitide, nitroglycerin, and nifedipine) were then established using organ baths. All the vasoconstrictors and vasodilators produced concentration-dependent responses in each section. As the concentration of the vasoconstrictors increased, segments at the distal section showed a significantly greater contraction than those at the middle and proximal sections regardless of the type of vasoconstrictor. The effective concentration of drugs that caused 50% of the maximal response for endothelin-1 was significantly greater in the distal section than that in the proximal sections. No significant difference was found in vasodilators-induced relaxation., Conclusions: The contractility increases toward to the end of the GEA. Clinically, the distal portion of the GEA should be trimmed off and not be used as an anastomotic site wherever possible.
- Published
- 2018
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41. Alpha7 nicotinic acetylcholine receptor-specific agonist DMXBA (GTS-21) attenuates Aβ accumulation through suppression of neuronal γ-secretase activity and promotion of microglial amyloid-β phagocytosis and ameliorates cognitive impairment in a mouse model of Alzheimer's disease.
- Author
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Takata K, Amamiya T, Mizoguchi H, Kawanishi S, Kuroda E, Kitamura R, Ito A, Saito Y, Tawa M, Nagasawa T, Okamoto H, Sugino Y, Takegami S, Kitade T, Toda Y, Kem WR, Kitamura Y, Shimohama S, and Ashihara E
- Subjects
- Alzheimer Disease complications, Animals, Cells, Cultured, Cognitive Dysfunction etiology, Disease Models, Animal, Humans, Mice, Transgenic, Neuroblastoma metabolism, Rats, Tumor Cells, Cultured, Alzheimer Disease drug therapy, Amyloid Precursor Protein Secretases metabolism, Amyloid beta-Peptides immunology, Amyloid beta-Peptides metabolism, Benzylidene Compounds pharmacology, Benzylidene Compounds therapeutic use, Brain metabolism, Cognitive Dysfunction drug therapy, Microglia immunology, Phagocytosis drug effects, Phagocytosis immunology, Pyridines pharmacology, Pyridines therapeutic use, alpha7 Nicotinic Acetylcholine Receptor agonists
- Abstract
We previously demonstrated that stimulation of nicotinic acetylcholine receptors (nAChRs) increases amyloid-β (Aβ) phagocytosis in rat microglia and is closely associated with the decrease of brain Aβ and amelioration of memory dysfunction in a transgenic mouse model of Alzheimer's disease (AD). Here, we examined the subtypes of nAChRs involved in these beneficial effects. In primary cultures of rat microglia, the α7 nAChR selective agonist 3-[(2,4-dimethoxy)benzylidene]-anabaseine dihydrochloride (DMXBA) promoted Aβ and fluorescent latex bead phagocytosis, whereas selective α7 nAChR antagonists suppressed the enhanced Aβ phagocytosis. In a transgenic mouse model of AD, administration of DMXBA attenuated brain Aβ burden and memory dysfunction. Moreover, DMXBA suppressed γ-secretase activity in solubilized fractions of human neuroblastoma cells and transgenic mouse brain. These results suggested that selective activation of α7 nAChRs promoted microglial Aβ phagocytosis and suppressed neuronal γ-secretase activity to contribute to the attenuation of the brain Aβ burden and cognitive impairment. Thus, we propose neuronal and microglial α7 nAChRs as new therapeutic targets in the treatment of AD., (Copyright © 2017 Elsevier Inc. All rights reserved.)
- Published
- 2018
- Full Text
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42. Suppression of Graft Spasm by the Particulate Guanylyl Cyclase Activator in Coronary Bypass Surgery.
- Author
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Kinoshita T, Tawa M, Suzuki T, Aimi Y, Asai T, and Okamura T
- Subjects
- Graft Occlusion, Vascular etiology, Graft Occlusion, Vascular physiopathology, Guanylate Cyclase metabolism, Humans, Mammary Arteries physiopathology, Mammary Arteries transplantation, Atrial Natriuretic Factor therapeutic use, Coronary Artery Bypass adverse effects, Graft Occlusion, Vascular prevention & control, Guanylate Cyclase drug effects, Mammary Arteries drug effects, Vasoconstriction drug effects
- Abstract
Background: Spasm of arterial grafts is still a clinical problem in coronary artery bypass surgery. The present study was designed to examine the effect of particulate guanylyl cyclase activator (carperitide) as an antispastic agent in internal thoracic artery and gastroepiploic artery grafts., Methods: Isolated arterial grafts taken during surgery were studied in organ bath in three ways: the relaxing effect of carperitide on vasoconstrictor-induced precontraction; the inhibitory effect of pretreatment with carperitide on subsequent vasoconstrictor-induced contraction; and the effect of carperitide and nitroglycerin on increase of intracellular cyclic guanosine monophosphate levels., Results: Carperitide produced a concentration-related, endothelium-independent relaxation contracted with potassium chloride, phenylephrine, prostaglandin F
2α , or endothelin-1. Carperitide showed significantly higher potency and efficacy than nitroglycerin and nifedipine. Pretreatment with carperitide significantly attenuated the subsequent vasoconstrictor-induced contraction. Carperitide produced more cyclic guanosine monophosphate than nitroglycerin., Conclusions: Carperitide has a potent inhibitory effect on the vasoconstriction mediated by different vasoconstrictors in human internal thoracic artery and gastroepiploic artery grafts. The use of carperitide in patients during and after coronary artery bypass surgery is favored for the prevention and reversal of graft spasm., (Copyright © 2017 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)- Published
- 2017
- Full Text
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43. N-3 Polyunsaturated Fatty Acids Decrease the Protein Expression of Soluble Epoxide Hydrolase via Oxidative Stress-Induced P38 Kinase in Rat Endothelial Cells.
- Author
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Okada T, Morino K, Nakagawa F, Tawa M, Kondo K, Sekine O, Imamura T, Okamura T, Ugi S, and Maegawa H
- Subjects
- Acetylcholine pharmacology, Animal Feed analysis, Animals, Antigens, CD, Aorta drug effects, Cadherins, Dietary Supplements, Docosahexaenoic Acids chemistry, Eicosapentaenoic Acid chemistry, Endothelial Cells metabolism, Epoxide Hydrolases genetics, Fish Oils chemistry, Food Analysis, Genes, Tumor Suppressor, Nuclear Proteins, RNA, Messenger genetics, RNA, Messenger metabolism, Rats, Real-Time Polymerase Chain Reaction, Renal Artery cytology, Vasodilation drug effects, p38 Mitogen-Activated Protein Kinases genetics, Docosahexaenoic Acids pharmacology, Eicosapentaenoic Acid pharmacology, Endothelial Cells drug effects, Epoxide Hydrolases metabolism, Gene Expression Regulation, Enzymologic drug effects, p38 Mitogen-Activated Protein Kinases metabolism
- Abstract
N -3 polyunsaturated fatty acids (PUFAs) improve endothelial function. The arachidonic acid-derived metabolites (epoxyeicosatrienoic acids (EETs)) are part of the endothelial hyperpolarization factor and are vasodilators independent of nitric oxide. However, little is known regarding the regulation of EET concentration by docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) in blood vessels. Sprague-Dawley rats were fed either a control or fish oil diet for 3 weeks. Compared with the control, the fish oil diet improved acetylcholine-induced vasodilation and reduced the protein expression of soluble epoxide hydrolase (sEH), a key EET metabolic enzyme, in aortic strips. Both DHA and EPA suppressed sEH protein expression in rat aorta endothelial cells (RAECs). Furthermore, the concentration of 4-hydroxy hexenal (4-HHE), a lipid peroxidation product of n -3 PUFAs, increased in n -3 PUFA-treated RAECs. In addition, 4-HHE treatment suppressed sEH expression in RAECs, suggesting that 4-HHE (derived from n -3 PUFAs) is involved in this phenomenon. The suppression of sEH was attenuated by the p38 kinase inhibitor (SB203580) and by treatment with the antioxidant N-acetyl-L-cysteine. In conclusion, sEH expression decreased after n -3 PUFAs treatment, potentially through oxidative stress and p38 kinase. Mild oxidative stress induced by n -3 PUFAs may contribute to their cardio-protective effect., Competing Interests: This study was performed by Shiga University of Medical Science in collaboration with CMIC Pharma Science. F.N. is an employee of CMIC Pharma Science Corporation and a graduate student at Shiga University of Medical Science. Shiga University of Medical Science receives grants from Mochida and Takeda. However, the research topics of these grants are not restricted. The founding sponsors had no role in the design of the study, in the collection, analyses, or interpretation of data, in the writing of the manuscript, or in the decision to publish the results.
- Published
- 2017
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44. Impact of type 2 diabetes on vascular reactivity to cGMP generators in human internal thoracic arteries.
- Author
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Tawa M, Kinoshita T, Asai T, Suzuki T, Imamura T, and Okamura T
- Subjects
- Aged, Diabetes Mellitus, Type 2 physiopathology, Dose-Response Relationship, Drug, Enzyme Activation, Female, Glycated Hemoglobin metabolism, Humans, In Vitro Techniques, Male, Mammary Arteries enzymology, Mammary Arteries pathology, Nitric Oxide metabolism, Cyclic GMP metabolism, Diabetes Mellitus, Type 2 enzymology, Enzyme Activators pharmacology, Mammary Arteries drug effects, Second Messenger Systems drug effects, Soluble Guanylyl Cyclase metabolism, Vasodilation drug effects, Vasodilator Agents pharmacology
- Abstract
Objective: The balance between nitric oxide (NO)-sensitive and -insensitive forms of soluble guanylate cyclase (sGC) has been demonstrated to be disrupted in certain lifestyle-related diseases. However, it remains unclear whether type 2 diabetes results in a shift of sGC to the NO-insensitive form. This study addressed this issue in the human blood vessel., Methods: Internal thoracic arteries were obtained from patients undergoing coronary artery bypass grafting. Helically cut strips of the arteries were suspended in organ chambers, and relaxant responses to nitroglycerin (NO-sensitive sGC stimulant) and BAY 60-2770 (NO-insensitive sGC stimulant) were assessed., Results: The patients were divided into two groups according to the presence of type 2 diabetes (HbA1c: 7.0±0.3%) or its absence (HbA1c: 5.6±0.1%). Nitroglycerin-induced relaxation was not different in the arteries obtained from type 2 diabetic and non-diabetic patients. In addition, the relaxant response to BAY 60-2770 in type 2 diabetics was comparable to that observed in non-diabetics. Although the patients enrolled often had vascular risk factors other than type 2 diabetes, the relaxant responses were still in the same range in a comparison based on the number of risk factors. However, in separate experiments, the relaxant response to nitroglycerin was attenuated by pre-incubation of the arteries with ODQ (sGC imbalance inducer), whereas the relaxant response to BAY-60-2770 was augmented., Conclusions: These findings suggest that type 2 diabetes does not affect the balance between NO-sensitive and -insensitive sGC in human internal thoracic artery grafts., (Copyright © 2017 Elsevier Inc. All rights reserved.)
- Published
- 2017
- Full Text
- View/download PDF
45. Aprepitant for refractory cutaneous T-cell lymphoma-associated pruritus: 4 cases and a review of the literature.
- Author
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Song JS, Tawa M, Chau NG, Kupper TS, and LeBoeuf NR
- Subjects
- Adult, Aged, Aprepitant, Female, Humans, Lymphoma, T-Cell, Cutaneous complications, Lymphoma, T-Cell, Cutaneous genetics, Lymphoma, T-Cell, Cutaneous pathology, Male, Middle Aged, Neurokinin-1 Receptor Antagonists administration & dosage, Protein Binding drug effects, Pruritus genetics, Pruritus pathology, Substance P antagonists & inhibitors, Substance P genetics, Lymphoma, T-Cell, Cutaneous drug therapy, Morpholines administration & dosage, Pruritus drug therapy
- Abstract
Background: Aprepitant is an FDA-approved medication for chemotherapy-induced nausea and vomiting. It blocks substance P binding to neurokinin-1; substance P has been implicated in itch pathways both as a local and global mediator., Case Presentations: We report a series of four patients, diagnosed with cutaneous T-cell lymphoma, who experienced full body pruritus recalcitrant to standard therapies. All patients experienced rapid symptom improvement (within days) following aprepitant treatment., Conclusion: Aprepitant has been shown in small studies to be efficacious for treating chronic and malignancy-associated pruritus. Prior studies have shown no change in clinical efficacy of chemotherapeutics with concurrent aprepitant administration. These cases further demonstrate that aprepitant can be considered as a therapeutic option in malignancy-associated pruritus and further support the need for larger clinical trials.
- Published
- 2017
- Full Text
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46. Endothelial dysfunction of internal thoracic artery graft in patients with chronic kidney disease.
- Author
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Kinoshita T, Tawa M, Suzuki T, Aimi Y, Asai T, and Okamura T
- Subjects
- Acetylcholine pharmacology, Coronary Artery Disease complications, Coronary Artery Disease physiopathology, Female, Glomerular Filtration Rate, Humans, Male, Mammary Arteries drug effects, Mammary Arteries transplantation, Nitroprusside pharmacology, Renal Insufficiency, Chronic physiopathology, Vasodilation drug effects, Vasodilator Agents pharmacology, Coronary Artery Bypass methods, Coronary Artery Disease surgery, Endothelium, Vascular physiopathology, Mammary Arteries physiopathology, Renal Insufficiency, Chronic complications, Vascular Patency physiology, Vasodilation physiology
- Abstract
Objectives: The present study was designed to evaluate the association between chronic kidney disease and the endothelial function of internal thoracic artery (ITA) grafts in patients undergoing coronary bypass surgery. An isometric tension study was performed in ITA strips obtained during surgery. Concentration-response curves for acetylcholine (ACh) and sodium nitroprusside were constructed in ITA strips partially precontracted with phenylephrine under the inhibition of cyclooxygenase. The integrity of the endothelium was verified histologically by en-face staining of the luminal surface with the use of silver nitrate solution., Results: In endothelium-intact ITA strips, ACh produced a concentration-dependent relaxation in patients with glomerular filtration rate (GFR, mL/min/1.73 m
2 ) > 60. A concentration-dependent relaxation response also was observed in patients with GFR 30 to 60, but it was reduced significantly compared with those with GFR > 60. In both groups, removal of endothelium or treatment with nitric oxide (NO) synthase inhibitors almost abolished the ACh-induced relaxation. On the other hand, in patients with GFR < 30, mild contraction rather than relaxation was induced at a high concentration of ACh, which was modified neither by treatment with NO synthase inhibitors nor by removal of the endothelium. Vasodilator responses to sodium nitroprusside were comparable among the 3 groups. The relaxation of endothelium-intact strips to a peak ACh concentration correlated positively with GFR. This relationship held true in a multiple linear regression model, and interaction terms between GFR and other risk factors were not statistically significant., Conclusions: Endothelial function of ITA grafts to release NO is impaired at the time of surgery in patients with chronic kidney disease., (Copyright © 2016 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.)- Published
- 2017
- Full Text
- View/download PDF
47. Responsiveness of Coronary Arteries to Nitroglycerin under Hypoxia: The Importance of the Endothelium.
- Author
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Tawa M, Shimosato T, Sakonjo H, and Okamura T
- Subjects
- Animals, Dose-Response Relationship, Drug, Female, In Vitro Techniques, Macaca, Male, Rabbits, Swine, Coronary Vessels drug effects, Endothelium, Vascular drug effects, Endothelium, Vascular physiology, Hypoxia physiopathology, Nitroglycerin pharmacology, Vasodilation drug effects, Vasodilation physiology
- Abstract
Background/aims: Nitroglycerin is widely used as a coronary vasodilator in the treatment of ischemic heart diseases. This study investigated the influence of hypoxia on nitroglycerin-induced relaxation in endothelium-intact and -denuded rabbit, monkey, and porcine coronary arteries., Methods: Helically cut strips of coronary arteries were suspended in organ chambers, and isometric tension was recorded., Results: Nitroglycerin concentration dependently relaxed endothelium-intact rabbit coronary arteries, which were not different under normoxic and hypoxic conditions. On the other hand, nitroglycerin-induced relaxation of endothelium-denuded arteries was significantly attenuated by hypoxia. Similarly, the relaxant response of endothelium-intact monkey coronary arteries to nitroglycerin was not affected by hypoxia, whereas that of endothelium-denuded arteries was impaired. As is the case with rabbit and monkey coronary arteries, exposure to hypoxia resulted in impaired relaxation by nitroglycerin in endothelium-denuded but not endothelium-intact porcine coronary arteries., Conclusion: These findings suggest that coronary endothelium plays a pivotal role in preventing the hypoxia-induced impairment of nitroglycerin responsiveness, regardless of the animal species., (© 2017 S. Karger AG, Basel.)
- Published
- 2017
- Full Text
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48. Soluble guanylate cyclase redox state under oxidative stress conditions in isolated monkey coronary arteries.
- Author
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Tawa M and Okamura T
- Abstract
Coronary artery disease is associated with oxidative stress due to the excessive generation of free radicals in the vascular wall. This study investigated the impact of tert-butyl hydroperoxide (t-BuOOH), a peroxyl radical generator, on the redox state of soluble guanylate cyclase (sGC) in isolated monkey coronary arteries. Helically cut strips of endothelium-intact monkey coronary arteries treated with the nitric oxide synthase inhibitor N
G -nitro-L-arginine (10 μ mol/L) were exposed for approximately 60 min to either no drug or t-BuOOH (100 μ mol/L) in the presence and absence of α -tocopherol (300 μ mol/L). Relaxation and cGMP levels in response to the sGC stimulator BAY 41-2272 and the sGC activator BAY 60-2770 were assessed by organ chamber technique and enzyme immunoassay, respectively. The relaxant response to BAY 41-2272 was significantly impaired by the exposure to t-BuOOH, whereas the response to BAY 60-2770 was significantly augmented. In addition, vascular cGMP accumulation caused by BAY 41-2272 was decreased by the exposure to t-BuOOH, whereas for BAY 60-2770, it was increased. These effects of t-BuOOH were abolished by coincubation with α -tocopherol. Furthermore, correlations were observed between BAY compound-induced relaxant magnitudes and cGMP levels. Therefore, it is concluded that increased oxidative stress leads to disruption of the sGC redox state in monkey coronary arteries. This finding is of great importance for understanding coronary physiology in primates.- Published
- 2016
- Full Text
- View/download PDF
49. Aging does not affect soluble guanylate cyclase redox state in mouse aortas.
- Author
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Shimosato T, Tawa M, Iwasaki H, Imamura T, and Okamura T
- Subjects
- Aging drug effects, Animals, Aorta, Thoracic drug effects, Benzoates pharmacology, Biphenyl Compounds pharmacology, Hydrocarbons, Fluorinated pharmacology, Male, Mice, Organ Culture Techniques, Oxidation-Reduction drug effects, Pyrazoles pharmacology, Pyridines pharmacology, Soluble Guanylyl Cyclase, Aging metabolism, Aorta, Thoracic metabolism, Guanylate Cyclase metabolism, Receptors, Cytoplasmic and Nuclear metabolism
- Abstract
Aging is associated with endothelial dysfunction, defined as a reduction in nitric oxide (NO) bioavailability. Although the redox state of the NO acceptor soluble guanylate cyclase (sGC) is another determinant factor for its bioavailability and is disturbed by reactive oxygen species (ROS) known to be increased with age, it is unclear whether aging actually has an impact on vascular sGC redox equilibrium. Therefore, this study investigated this issue using two different types of compounds, the sGC stimulator BAY 41-2272 and the sGC activator BAY 60-2770. Plasma thiobarbituric acid-reactive substances (TBARS) levels were markedly higher in aged (19-20 months old) mice than in young (2-3 months old) mice, whereas superoxide levels in endothelium-denuded aortas were not different between the groups. The relaxant response of endothelium-denuded aortas to either BAY 41-2272 or BAY 60-2770 was identical in aged and young mice. In addition, the vascular cGMP production stimulated with BAY 41-2272 or BAY 60-2770 in aged mice was the same level as that in young mice. These findings suggest that aging accompanied by an increase in systemic oxidative stress does not affect vascular smooth muscle ROS generation and sGC redox equilibrium. Unless ROS are increased in vascular smooth muscle, the sGC redox equilibrium might remain unchanged., (© 2016 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of the American Physiological Society and The Physiological Society.)
- Published
- 2016
- Full Text
- View/download PDF
50. MicroRNA-494 plays a role in fiber type-specific skeletal myogenesis in human induced pluripotent stem cells.
- Author
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Iwasaki H, Imamura T, Morino K, Shimosato T, Tawa M, Ugi S, Sakurai H, Maegawa H, and Okamura T
- Subjects
- Cell Line, Down-Regulation, Gene Expression Regulation, Developmental, Humans, Induced Pluripotent Stem Cells cytology, MicroRNAs metabolism, Mitochondria, Muscle metabolism, Muscle Fibers, Skeletal cytology, Muscle, Skeletal metabolism, Up-Regulation, Induced Pluripotent Stem Cells metabolism, MicroRNAs genetics, Muscle Development, Muscle Fibers, Skeletal metabolism, Muscle, Skeletal growth & development
- Abstract
Mitochondrial oxidative capacity in skeletal muscle is known to decrease in diabetic patients, and sarcopenia is a risk factor for diabetes, particularly in elderly people. We previously revealed that microRNA (miR)-494 inhibits mitochondrial biogenesis during myogenic differentiation in murine C2C12 cells and others reported that exercise regulates miR-494 levels in obese sedentary individuals with increased risk of type 2 diabetes. In this study, to investigate the therapeutic potential of miR-494, we first investigated the role of miR-494 during human skeletal myogenesis. Using human induced pluripotent stem (hiPS) cells stably transfected with the Tet/ON-myogenic differentiation 1(MYOD1) gene (MyoD-hiPS cells), we found that miR-494 expression transiently increased and was downregulated after myogenic induction. In miR-494 transfected MyoD-hiPS cells, the level of high oxidative fiber (type IIa) marker proteins specifically decreased, while no change in the total number of cells was observed. In contrast, the expression of both type I and type IIx markers was unaffected by miR-494 overexpression. Furthermore, miR-494 overexpression suppressed basal oxygen consumption rate concomitant with the inhibition of myotube formation and without significant effects on the mitochondrial content. These results suggest that miR-494 plays a novel role in the fiber type-specific skeletal myogenesis in MyoD-hiPS cells, distinct from murine C2C12 myogenesis., (Copyright © 2015 Elsevier Inc. All rights reserved.)
- Published
- 2015
- Full Text
- View/download PDF
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