77 results on '"Kurgan N"'
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2. Design of the electronic structure and properties of calcium apatites via isomorphic modification of the cation sublattice, and prospects of their application.
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Karbivskyy, V., Kurgan, N., Hantusch, M., Romansky, A., Sukhenko, I., and Karbivska, L.
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ELECTRONIC structure , *RARE earth metals , *APATITE , *COPPER , *IRON clusters , *VALENCE bands - Abstract
The evolution of the valence band, charge states of atoms, and optical and vibrational spectra in compounds Ca10−xMx(PO4)xY2, M = Fe, Ni, Cu, Mg; Y = OH, Cl, F was studied by using XPS, infrared, and optical spectroscopy, with the addition of quantum mechanics calculations. The changes in the bandgap in these compounds were analyzed. Isomorphic substitution of calcium ions in the cationic sublattice of calcium hydroxyapatite by metal ions changes the shape of the curve that represents the occupied part of the valence band only slightly. It retains a pronounced gapped character with different lengths of individual subbands—the upper and lower parts of the valence band. It is shown that the predominant position of rare earth and uranium atoms in the apatite structure is the Ca(2)-position. Isomorphic substitution of calcium atoms by metal atoms (Fe, Ni, Cu, Mg) in the apatite structure in the range of 1%–2% of atoms leads to the narrowing of the energy gap. The most significant narrowing is observed when calcium is substituted by nickel and copper. The theoretically calculated bandgap width in calcium apatites can be well described in terms of the generalized gradient approximation. The design of the structure of calcium apatites via the method of isomorphic substitutions in the cation sublattice makes it possible to control the bandgap width, thus expanding the field of practical application of these compounds. [ABSTRACT FROM AUTHOR]
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- 2024
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3. Spectral and quantum mechanical investigation of calcium apatites isomorphically substituted in the anionic sublattice
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Karbivskyy, V., Kurgan, N., Huntush, M., Romansky, A., Karbivska, L., and Zaika, V.
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- 2023
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4. Spectral Investigations of 60S Bioactive Glass Modified with La and Y Ions
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Karbivskyy, V., primary, Kurgan, N., additional, Kasyianenko, V., additional, Sukhenko, I., additional, Smolyak, S., additional, Zaika, V., additional, and Dubok, V., additional
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- 2024
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5. Electronic structure and surface morphology of multicomponent iron-based metallic glasses
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Karbivskyy, V. L., primary, Kurgan, N. A., additional, Nosenko, V. K., additional, Zaika, V. V., additional, Zueva, N. A., additional, Karbivska, L. I., additional, and Shulyma, S. I., additional
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- 2022
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6. Structural and Physical Properties of Ultrathin Bismuth Films
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Karbivskyy, V. L., primary, Zaika, V. V., additional, Karbivska, L. I., additional, Kurgan, N. A., additional, and Zueva, N. O., additional
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- 2021
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7. Response of Sclerostin and Bone Turnover Markers to High Intensity Interval Exercise in Young Women: Does Impact Matter?
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Kouvelioti, R., primary, Kurgan, N., additional, Falk, B., additional, Ward, W. E., additional, Josse, A. R., additional, and Klentrou, P., additional
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- 2018
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8. Quantum Nature of Stability Mechanisms of Calcium Apatite Structure.
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Karbovska, L. I., Karbivskyy, V. L., Kurgan, N. A., Romansky, A. O., Kuznetsova, O. Ya., and Soroka, A. P.
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APATITE ,CALCIUM compounds ,CALCIUM ,DENSITY functionals ,DENSITY functional theory ,COMPOSITION operators - Abstract
Copyright of Nanosistemi, Nanomateriali, Nanotehnologii is the property of G.V. Kurdyumov Institute for Metal Physics, N.A.S.U and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2019
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9. Informational support of export efficiency of company in conditions of automation of accounting and analytical process
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Kurgan, N.
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НЕРЕЗИДЕНТ, ЕКСПОРТ, ЗОВНіШНЬОЕКОНОМіЧНА ДіЯЛЬНіСТЬ, УПРАВЛіНСЬКИЙ ОБЛіК, РЕНТАБЕЛЬНіСТЬ ЕКСПОРТНОї ОПЕРАЦії - Abstract
The author proposed to use of management accounting as an information support for evaluating the profitability and efficiency of export operations of enterprises. This requires use computer programs to automate accounting and analytical functions. Financial indicators of management accounting full enough characterize the results by export operation in the material aspect. According to the author, if the company can not implement a comprehensive evaluation of the effectiveness of export operations based on the establishment of specialized additional departments, it may apply a simplified assessment in the sphere of management accounting. Automated analytical table is designed to determine the most profitable conditions of supply among several possible.
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- 2014
10. Mechanism of the combined reaction of butyl isocyanate and methanol with aerosil
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Kulik, N. V., Negievich, L. A., Kurgan, N. P., Belitskaya, G. F., and Kachan, A. A.
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- 1972
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11. Two-photon heterogeneous photodegradation of an aromatic polyurethane
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Kachan, A. A., Kurgan, N. P., Kulik, N. V., and Boyarskii, G. Ya.
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- 1971
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12. Prediction of losses of railways if traffic speed is limited
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Kurgan, N. B.; Dnipropetrovsk National University of Railway Transport named after Academician V. Lazaryan, Chernyshova, O. S.; Dnipropetrovsk National University of Railway Transport named after Academician V. Lazaryan, Kurgan, N. B.; Dnipropetrovsk National University of Railway Transport named after Academician V. Lazaryan, and Chernyshova, O. S.; Dnipropetrovsk National University of Railway Transport named after Academician V. Lazaryan
- Abstract
The technique and results of studies of efficiency of removing the speed limits of train traffic are presented., Изложены методика и результаты исследований эффективности устранения ограничений скорости движения поездов., Наведено методику і результати досліджень ефективності усунення обмежень швидкості руху поїздів.
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- 2012
13. Reconstruction of curves for introduction of highspeed traffic of passenger trains
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Kurgan, N. B.; Dnipropetrovsk National University of Railway Transport named after Academician V. Lazaryan, Gusak, M. A.; Dnipropetrovsk National University of Railway Transport named after Academician V. Lazaryan, Khmelevs’ka, N. P.; Dnipropetrovsk National University of Railway Transport named after Academician V. Lazaryan, Kurgan, N. B.; Dnipropetrovsk National University of Railway Transport named after Academician V. Lazaryan, Gusak, M. A.; Dnipropetrovsk National University of Railway Transport named after Academician V. Lazaryan, and Khmelevs’ka, N. P.; Dnipropetrovsk National University of Railway Transport named after Academician V. Lazaryan
- Abstract
The technique of determining the rational parameters of radii and transitive curves, which provide as much as possible admissible speed at the minimum expenses for plan reconstruction, is presented., Приведена методика установления рациональных параметров радиусов и переходных кривых, которые обеспечивают максимально допустимую скорость при минимальных затратах на реконструкцию плана., Приведена методика визначення раціональних параметрів радіусів і перехідних кривих, які забезпечують максимально допустиму швидкість при мінімальних витратах на реконструкцію плану
- Published
- 2012
14. Reconstruction of curves for introduction of highspeed traffic of passenger trains
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Kurgan, N. B., primary, Gusak, M. A., additional, and Khmelevs’ka, N. P., additional
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- 2012
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15. Prediction of losses of railways if traffic speed is limited
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Kurgan, N. B., primary and Chernyshova, O. S., additional
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- 2012
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16. Mechanical properties of P/M 316L stainless steel materials
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Kurgan, N., primary and Varol, R., additional
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- 2010
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17. Properties of the Virus of the Tobacco Mosaic on the Si(111) Surface
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Shpak, A P, primary, Karbovsky, V L, additional, Korniyuk, T A, additional, and Kurgan, N A, additional
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- 2007
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18. Mechanism of the combined reaction of butyl isocyanate and methanol with aerosil.
- Author
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Kulik, N., Negievich, L., Kurgan, N., Belitskaya, G., and Kachan, A.
- Abstract
The joint sorption of butyl isocyanate and methanol vapors on pretreated Aerosil has been studied by infrared spectroscopy. We show that free hydroxyl radicals participate in the process to form a urethane chemically combined with the adsorbent. Methanol acts as a catalyst. The mechanism of the reaction is discussed. [ABSTRACT FROM AUTHOR]
- Published
- 1970
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19. Two-photon heterogeneous photodegradation of an aromatic polyurethane.
- Author
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Kachan, A., Kurgan, N., Kulik, N., and Boyarskii, G.
- Abstract
Glass, zinc, copper, or tin supports were shown to have a sensitizing action on the photochemical degradation of a polyurethane prepared from tolylene diisocyanate and trimethylol propane. It was shown that photodegradation of the polyurethane was linked with the breakdown of the isocyanate groups. It was concluded that a two-photon mechanism of heterogeneous photodegradation of the polyurethane operated. [ABSTRACT FROM AUTHOR]
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- 1968
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20. Strategic Management of Intangible Results of Innovation of the Company and the Cost of it’s Creating Стратегический управленческий учет нематериальных результатов инновационной деятельности предприятия и затрат на их создание
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Kurgan Natalya V. and Luchaninova Anna S.
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strategic managerial accounting ,financial accounting ,intangible assets ,innovation ,innovative activities ,innovative costs ,innovative cost management ,стратегический управленческий учет ,финансовый учет ,нематериальные активы ,инновация ,инновационная деятельность ,инновационные затраты ,управление инновационными затратами ,Business ,HF5001-6182 - Abstract
The article proposed to introduce a Strategic Managerial Accounting of innovations for improve the Financial Accounting and for preserve his value optimum information system for progressive innovative enterprises. The reasons for the limited Financial Accounting of intangible resources were studied. The tasks of Strategic Managerial Accounting were identified, given the information needs of management of innovation costs.В статье предложено внедрять стратегический управленческий учет инновационной деятельности для усовершенствования бухгалтерского учета и сохранения за ним значения оптимальной системы информационного обеспечения прогрессивных предприятий, которые систематически внедряют нововведения. Исследованы причины ограниченности финансового учета затрат на создание нематериальных ресурсов предприятия. Определены задачи стратегического управленческого учета с позиции информационных потребностей управления инновационными затратами.
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- 2012
21. EFFECT OF THE METAL SUPPORT ON PHOTOLYSIS OF AN ADDUCT WITH URETHANE AND ISOCYNATE GROUPS
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ARMY FOREIGN SCIENCE AND TECHNOLOGY CENTER WASHINGTON D C, Kurgan,N. P., ARMY FOREIGN SCIENCE AND TECHNOLOGY CENTER WASHINGTON D C, and Kurgan,N. P.
- Abstract
The compound, 3-isocyanato-4-methyl carbanilic acid triester with 2-ethyl-2-(hydroxymethyl)-1-3-propanediol, was photolyzed to help clarify the effects of metals surfaces in the photolysis of polyurethanes., Trans. of Unidentified Russian language article, 1968.
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- 1969
22. Influence of preparation conditions on the electronic structure of nanosize calcium hydroxyapatite
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Kurgan, N. A., Karbivskyy, V. L., Karbovska, L. I., and Svitlana Smolyak
23. Quantum nature of stability mechanisms of calcium apatite structure
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Karbovska, L. I., Karbivskyy, V. L., Kurgan, N. A., Anastas Romansky, Kuznetsova, O. Y., and Soroka, A. P.
24. Electron Structure of Calcium Hydroxyapatite Isomorphically Modified by Uranium
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Karbovskii, V. L., Vakhney, A. G., Didenko, R. V., Senkevich, A. I., Svitlana Smolyak, and Kurgan, N. A.
25. Tunnelling microscopy of formation processes of hexagonal-pyramidal Au nanoislands on silicon single-crystal surface
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Karbivs Kyy, V. L., Vyshnyak, V. V., Kurgan, N. A., and Kasiyanenko, V. Kh
26. Investigation of vibration anharmonicity in the crystal lattice of the mixed composition apatites
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Karbivskyy, V. L., Shpak, A. P., Kurgan, N. A., Vishnyak, V. V., Oleg Dimitriev, and Kasiyanenko, V. H.
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Characterization and properties
27. Morphology and spectral behavior of hydroxyapatite nanocrystalline coatings obtained by gas detonation deposition
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Karbovskii, V. L., Kurgan, N. A., Dubok, V. A., Klui, N. I., Kasiyanenko, V. K., Stonis, V. V., and Rozhkov, N. V.
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Characterization and properties - Abstract
Electronic structure and morphology of hydroxyapatite (HAP), deposited on titanium substrate by gas detonation deposition (GDD), was investigated by scanning probe microscopy of high resolution and spectroscopic methods. Nanoscale structure formation of the coatings in the form of nano-dispersed ceramics was determined. Effects of more advanced surface in the transition of HAP from the crystalline (powder) to nanodispersed (coating) state was studied. It is revealed that the elemental composition of GDD cover surface and subsurface layers remains stable up to the depth of 50 nm. The change of elemental composition of GDD cover subsurface layers in the direction of increasing the calcium and phosphorus content was observed in the range 50-150 nm.
28. Regularities of formation of electronic structure of nanodisperse apatites of calcium of various genealogy
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Kurgan, N. A., Karbivska, L. I., Karbivskyy, V. L., and Svitlana Smolyak
29. Harnessing the power of proteomics in precision diabetes medicine.
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Kurgan N, Kjærgaard Larsen J, and Deshmukh AS
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- Humans, Precision Medicine methods, Genomics methods, Prognosis, Proteomics methods, Diabetes Mellitus, Type 2 diagnosis, Diabetes Mellitus, Type 2 genetics, Diabetes Mellitus, Type 2 therapy
- Abstract
Precision diabetes medicine (PDM) aims to reduce errors in prevention programmes, diagnosis thresholds, prognosis prediction and treatment strategies. However, its advancement and implementation are difficult due to the heterogeneity of complex molecular processes and environmental exposures that influence an individual's disease trajectory. To address this challenge, it is imperative to develop robust screening methods for all areas of PDM. Innovative proteomic technologies, alongside genomics, have proven effective in precision cancer medicine and are showing promise in diabetes research for potential translation. This narrative review highlights how proteomics is well-positioned to help improve PDM. Specifically, a critical assessment of widely adopted affinity-based proteomic technologies in large-scale clinical studies and evidence of the benefits and feasibility of using MS-based plasma proteomics is presented. We also present a case for the use of proteomics to identify predictive protein panels for type 2 diabetes subtyping and the development of clinical prediction models for prevention, diagnosis, prognosis and treatment strategies. Lastly, we discuss the importance of plasma and tissue proteomics and its integration with genomics (proteogenomics) for identifying unique type 2 diabetes intra- and inter-subtype aetiology. We conclude with a call for action formed on advancing proteomics technologies, benchmarking their performance and standardisation across sites, with an emphasis on data sharing and the inclusion of diverse ancestries in large cohort studies. These efforts should foster collaboration with key stakeholders and align with ongoing academic programmes such as the Precision Medicine in Diabetes Initiative consortium., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)
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- 2024
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30. Effects of sclerostin injection on soleus and extensor digitorum longus muscle tissue in male mice.
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Stoikos J, Kurgan N, Kottaras S, Fajardo VA, Gittings W, and Klentrou P
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- Animals, Male, Mice, Mice, Inbred C57BL, Myosin Heavy Chains metabolism, Pilot Projects, Muscle Fibers, Fast-Twitch metabolism, Muscle, Skeletal metabolism
- Abstract
Sclerostin, a potent inhibitor of the Wnt signaling pathway, plays a critical role in bone homeostasis. Evidence suggests that sclerostin may also be involved in crosstalk between other tissues, including muscle. This pilot study attempted to examine the effects of sclerostin on soleus and extensor digitorum longus (EDL) muscle tissue from male mice that were given continuous recombinant sclerostin injections for 4 weeks. A total of 48 10-week-old male C57BL/6J mice were assigned to be sedentary or perform 1 h treadmill running per day for 4 weeks and administered subcutaneous injections of either saline or recombinant sclerostin 5 days/week. Sclerostin injection led to a reduction in the soleus myosin heavy chain (MHC) I, MHC I/IIA, MHC IIA/X, and MHC IIB cross-sectional area ( p < 0.05) with no exercise effects on these reductions. In contrast, there were no effects of sclerostin injections or exercise on the fast-twitch EDL muscle in terms of size, MHC protein, or markers of Wnt signaling. These findings provide preliminary evidence of sclerostin's endocrine role in muscle via decreases in myofiber cross-sectional area, which seems to be independent of fiber type but muscle type-specific. More studies, however, are needed to confirm these preliminary results., Competing Interests: The authors declare no conflict of interest.
- Published
- 2024
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31. Targeting postsynaptic glutamate receptor scaffolding proteins PSD-95 and PICK1 for obesity treatment.
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Fadahunsi N, Petersen J, Metz S, Jakobsen A, Vad Mathiesen C, Silke Buch-Rasmussen A, Kurgan N, Kjærgaard Larsen J, Andersen RC, Topilko T, Svendsen C, Apuschkin M, Skovbjerg G, Hendrik Schmidt J, Houser G, Elgaard Jager S, Bach A, Deshmukh AS, Kilpeläinen TO, Strømgaard K, Madsen KL, and Clemmensen C
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- Animals, Humans, Mice, Adaptor Proteins, Signal Transducing metabolism, Disks Large Homolog 4 Protein genetics, Disks Large Homolog 4 Protein metabolism, Receptors, Glutamate genetics, Receptors, Glutamate metabolism, Receptors, N-Methyl-D-Aspartate genetics, Genome-Wide Association Study, Receptors, AMPA genetics, Receptors, AMPA metabolism
- Abstract
Human genome-wide association studies (GWAS) suggest a functional role for central glutamate receptor signaling and plasticity in body weight regulation. Here, we use UK Biobank GWAS summary statistics of body mass index (BMI) and body fat percentage (BF%) to identify genes encoding proteins known to interact with postsynaptic α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) and N -methyl-d-aspartate (NMDA) receptors. Loci in/near discs large homolog 4 ( DLG4 ) and protein interacting with C kinase 1 ( PICK1 ) reached genome-wide significance ( P < 5 × 10
- 8 ) for BF% and/or BMI. To further evaluate the functional role of postsynaptic density protein-95 (PSD-95; gene name: DLG4 ) and PICK1 in energy homeostasis, we used dimeric PSD-95/disc large/ZO-1 (PDZ) domain-targeting peptides of PSD-95 and PICK1 to demonstrate that pharmacological inhibition of PSD-95 and PICK1 induces prolonged weight-lowering effects in obese mice. Collectively, these data demonstrate that the glutamate receptor scaffolding proteins, PICK1 and PSD-95, are genetically linked to obesity and that pharmacological targeting of their PDZ domains represents a promising therapeutic avenue for sustained weight loss.- Published
- 2024
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32. Toward countering muscle and bone loss with spaceflight: GSK3 as a potential target.
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Baranowski RW, Braun JL, Hockey BL, Yumol JL, Geromella MS, Watson CJF, Kurgan N, Messner HN, Whitley KC, MacNeil AJ, Gauquelin-Koch G, Bertile F, Gittings W, Vandenboom R, Ward WE, and Fajardo VA
- Abstract
We examined the effects of ∼30 days of spaceflight on glycogen synthase kinase 3 (GSK3) content and inhibitory serine phosphorylation in murine muscle and bone samples from four separate missions (BION-M1, rodent research [RR]1, RR9, and RR18). Spaceflight reduced GSK3β content across all missions, whereas its serine phosphorylation was elevated with RR18 and BION-M1. The reduction in GSK3β was linked to the reduction in type IIA fibers commonly observed with spaceflight as these fibers are particularly enriched with GSK3. We then tested the effects of inhibiting GSK3 before this fiber type shift, and we demonstrate that muscle-specific Gsk3 knockdown increased muscle mass, preserved muscle strength, and promoted the oxidative fiber type with Earth-based hindlimb unloading. In bone, GSK3 activation was enhanced after spaceflight; and strikingly, muscle-specific Gsk3 deletion increased bone mineral density in response to hindlimb unloading. Thus, future studies should test the effects of GSK3 inhibition during spaceflight., Competing Interests: The authors declare no competing interests., (© 2023 The Author(s).)
- Published
- 2023
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33. Sclerostin Influences Exercise-Induced Adaptations in Body Composition and White Adipose Tissue Morphology in Male Mice.
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Kurgan N, Stoikos J, Baranowski BJ, Yumol J, Dhaliwal R, Sweezey-Munroe JB, Fajardo VA, Gittings W, Macpherson REK, and Klentrou P
- Subjects
- Animals, Male, Mice, Adipose Tissue metabolism, Adipose Tissue, White metabolism, Body Composition, Mice, Inbred C57BL, Physical Conditioning, Animal physiology, Adaptor Proteins, Signal Transducing metabolism
- Abstract
Sclerostin is an inhibitor of the osteogenic Wnt/β-catenin signaling pathway that also has an endocrine role in regulating adipocyte differentiation and metabolism. Additionally, subcutaneous white adipose tissue (scWAT) sclerostin content decreases following exercise training (EXT). Therefore, we hypothesized that EXT-induced reductions in adipose tissue sclerostin may play a role in regulating adaptations in body composition and whole-body metabolism. To test this hypothesis, 10-week-old male C57BL/6J mice were either sedentary (SED) or performing 1 hour of treadmill running at ~65% to 70% maximum oxygen consumption (VO
2max ) 5 day/week (EXT) for 4 weeks and had subcutaneous injections of either saline (C) or recombinant sclerostin (S) (0.1 mg/kg body mass) 5 day/week; thus, making four groups (SED-C, EXT-C, SED-S, and EXT-S; n = 12/group). No differences in body mass were observed between experimental groups, whereas food intake was higher in EXT (p = 0.03) and S (p = 0.08) groups. There was a higher resting energy expenditure in all groups compared to SED-C. EXT-C had increased lean mass and decreased fat mass percentage compared to SED-C and SED-S. No differences in body composition were observed in either the SED-S or EXT-S groups. Lower scWAT (inguinal), epididymal white adipose tissue (eWAT) (visceral epididymal) mass, and scWAT adipocyte cell size and increased percentage of multilocular cells in scWAT were observed in the EXT-C group compared to SED-C, whereas lower eWAT was only observed in the EXT-S group. EXT mice had increased scWAT low-density lipoprotein receptor-related protein 4 (Lrp4) and mitochondrial content and sclerostin treatment only inhibited increased Lrp4 content with EXT. Together, these results provide evidence that reductions in resting sclerostin with exercise training may influence associated alterations in energy metabolism and body composition, particularly in scWAT. © 2023 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR)., (© 2023 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).)- Published
- 2023
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34. Twelve weeks of a diet and exercise intervention alters the acute bone response to exercise in adolescent females with overweight/obesity.
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Kurgan N, Skelly LE, Ludwa IA, Klentrou P, and Josse AR
- Abstract
Introduction: Exercise and consumption of dairy foods have been shown to improve bone mineralization. However, little is known about the magnitude and timing of their synergistic effects on markers and regulators of bone metabolism in response to acute exercise in adolescent females with obesity, a population susceptible to altered bone metabolism and mineral properties. This study examined the influence of twelve weeks of exercise training and nutritional counselling on the bone biochemical marker response to acute exercise and whether higher dairy consumption could further influence the response. Methods: Thirty adolescent females (14.3 ± 2.0 years) with overweight/obesity (OW/OB) completed a 12-week lifestyle modification intervention involving exercise training and nutritional counselling. Participants were randomized into two groups: higher dairy intake (RDa; 4 servings/day; n = 14) or low dairy intake (LDa; 0-2 servings/d; n = 16). Participants performed one bout of plyometric exercise (5 circuits; 120 jumps) both pre- and post-intervention. Blood samples were taken at rest, 5 min and 1 h post-exercise. Serum sclerostin, osteocalcin (OC), osteoprotegerin (OPG), receptor activator nuclear factor kappa B ligand (RANKL), and C-terminal telopeptide of type 1 collagen (βCTX) concentrations were measured. Results: While there was an overall increase in sclerostin pre-intervention from pre to 5 min post-exercise (+11% p = 0.04), this response was significantly decreased post-intervention (-25%, p = 0.03) independent of dairy intake. The OPG:RANKL ratio was unresponsive to acute exercise pre-intervention but increased 1 h post-exercise (+2.6 AU; p < 0.001) post-intervention. Dairy intake did not further influence these absolute responses. However, after the 12-week intervention, the RDa group showed a decrease in the relative RANKL post-exercise response (-21.9%; p < 0.01), leading to a consistent increase in the relative OPG:RANKL ratio response, which was not the case in the LDa group. There was no influence of the intervention or dairy product intake on OC, OPG, or βCTX responses to acute exercise (p > 0.05). Conclusion: A lifestyle modification intervention involving exercise training blunts the increase in sclerostin and can augment the increase in OPG:RANKL ratio to acute exercise in adolescent females with OW/OB, while dairy product consumption did not further influence these responses., Competing Interests: AJ and PK report grants for this research from Dairy Farmers of Canada, US National Dairy Council (Dairy Management Inc.), and non-financial support from Danone and Parmalat during the conduct of the study. LS reports some salary support from the US National Dairy Council. AJ reports consultant/speaker fees from Dairy Farmers of Canada Grant Review Board outside of this work. AJ and LS report additional grant funding from Dairy Farmers of Canada and non-financial support from Lactalis Canada outside of this work. The remaining 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 © 2023 Kurgan, Skelly, Ludwa, Klentrou and Josse.)
- Published
- 2023
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35. Characterization of sclerostin's response within white adipose tissue to an obesogenic diet at rest and in response to acute exercise in male mice.
- Author
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Kurgan N, Baranowski B, Stoikos J, MacNeil AJ, Fajardo VA, MacPherson REK, and Klentrou P
- Abstract
Introduction: It is well established that sclerostin antagonizes the anabolic Wnt signalling pathway in bone, however, its physiological role in other tissues remains less clear. This study examined the effect of a high-fat diet (HFD) on sclerostin content and downstream markers of the Wnt signaling pathway (GSK3β and β-catenin) within subcutaneous inguinal white adipose tissue (iWAT), and visceral epididymal WAT (eWAT) depots at rest and in response to acute aerobic exercise. Methods: Male C57BL/6 mice ( n = 40, 18 weeks of age) underwent 10 weeks of either a low-fat diet (LFD) or HFD. Within each diet group, mice were assigned to either remain sedentary (SED) or perform 2 h of endurance treadmill exercise at 15 m min
-1 with 5° incline (EX), creating four groups: LFD + SED ( N = 10), LFD + EX ( N = 10), HFD + SED ( N = 10), and HFD + EX ( N = 10). Serum and WAT depots were collected 2 h post-exercise. Results : Serum sclerostin showed a diet-by-exercise interaction, reflecting HFD + EX mice having higher concentration than HFD + SED (+31%, p = 0.03), and LFD mice being unresponsive to exercise. iWAT sclerostin content decreased post-exercise in both 28 kDa (-31%, p = 0.04) and 30 kDa bands (-36%, main effect for exercise, p = 0.02). iWAT β-catenin (+44%, p = 0.03) and GSK3β content were higher in HFD mice compared to LFD (+128%, main effect for diet, p = 0.005). Monomeric sclerostin content was abolished in eWAT of HFD mice (-96%, main effect for diet, p < 0.0001), was only detectable as a 30 kDa band in LFD mice and was unresponsive to exercise. β-catenin and GSK3β were both unresponsive to diet and exercise within eWAT. Conclusion : These results characterized sclerostin's content to WAT depots in response to acute exercise, which appears to be specific to a reduction in iWAT and identified a differential regulation of sclerostin's form/post-translational modifications depending on diet and WAT depot., 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 © 2023 Kurgan, Baranowski, Stoikos, MacNeil, Fajardo, MacPherson and Klentrou.)- Published
- 2023
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36. Correction: Klentrou et al. Circulating Levels of Bone Markers after Short-Term Intense Training with Increased Dairy Consumption in Adolescent Female Athletes. Children 2021, 8 , 961.
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Klentrou P, McKee K, McKinlay BJ, Kurgan N, Roy BD, and Falk B
- Abstract
There was an error in the original publication [...].
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- 2023
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37. Correction: McKinlay et al. Effects of Post-Exercise Whey Protein Consumption on Recovery Indices in Adolescent Swimmers. Int. J. Environ. Res. Public Health 2020, 17 , 7761.
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McKinlay BJ, Theocharidis A, Adebero T, Kurgan N, Fajardo VA, Roy BD, Josse AR, Logan-Sprenger HM, Falk B, and Klentrou P
- Abstract
The authors of "Effects of Post-Exercise Whey Protein Consumption on Recovery Indices in Adolescent Swimmers" report an error in Table 1 of their article [...].
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- 2022
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38. Kynurenine metabolism is altered in mdx mice: a potential muscle to brain connection.
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Copeland EN, Watson CJF, Whitley KC, Baranowski BJ, Kurgan N, MacNeil AJ, MacPherson REK, Fajardo VA, and Allison DJ
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- Animals, Brain metabolism, Disease Models, Animal, Kynurenic Acid metabolism, Kynurenic Acid pharmacology, Kynurenine metabolism, Kynurenine pharmacology, Mice, Mice, Inbred C57BL, Mice, Inbred DBA, Mice, Inbred mdx, Muscle, Skeletal metabolism, Peroxisome Proliferator-Activated Receptors metabolism, Tumor Necrosis Factor-alpha metabolism, Muscular Dystrophy, Duchenne metabolism
- Abstract
New Findings: What is the central question in this study? Promoting muscle health with regular aerobic exercise can improve mental health through a kynurenine metabolic pathway: do conditions of muscle disease such as muscular dystrophy negatively influence this pathway? What is the main finding and its importance? The DBA/2J mdx model of Duchenne muscular dystrophy exhibits altered kynurenine metabolism with less kynurenic acid and peroxisome proliferator-activated receptor-γ coactivator 1-α and higher levels of tumour necrosis factor α mRNA - results associated with anxiety-like behaviour., Abstract: Regular exercise can direct muscle kynurenine (KYN) metabolism toward the neuroprotective branch of the kynurenine pathway thereby limiting the accumulation of neurotoxic metabolites in the brain and contributing to mental resilience. However, the effect of muscle disease on KYN metabolism has not yet been investigated. Previous work has highlighted anxiety-like behaviours in approximately 25% of patients with Duchenne muscular dystrophy (DMD), possibly due to altered KYN metabolism. Here, we characterized KYN metabolism in mdx mouse models of DMD. Young (8-10 week old) DBA/2J (D2) mdx mice, but not age-matched C57BL/10 (C57) mdx mice, had lower levels of circulating kynurenic acid (KYNA) and lower KYNA:KYN ratio compared with their respective wild-type (WT) controls. While both C57 and D2 mdx mice displayed signs of anxiety-like behaviour, spending more time in the corners of the arena during a novel object recognition test, this effect was more prominent in D2 mdx mice. Correlational analysis detected a significant negative association between KYNA:KYN levels and time spent in corners in D2 mice, but not C57 mice. In extensor digitorum longus muscles from D2 mdx mice, but not C57 mdx mice, we found lowered protein levels of peroxisome proliferator-activated receptor-γ coactivator 1-α and kynurenine amino transferase-1 enzyme when compared with WT. Furthermore, D2 mdx quadriceps muscles had the highest level of tumour necrosis factor α expression, which is suggestive of enhanced inflammation. Thus, our pilot work shows that KYN metabolism is altered in D2 mdx mice, with a potential contribution from altered muscle health., (© 2022 The Authors. Experimental Physiology © 2022 The Physiological Society.)
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- 2022
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39. Menstrual Cycle Related Fluctuations in Circulating Markers of Bone Metabolism at Rest and in Response to Running in Eumenorrheic Females.
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Guzman A, Kurgan N, Moniz SC, McCarthy SF, Sale C, Logan-Sprenger H, Elliott-Sale KJ, Hazell TJ, and Klentrou P
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- Adolescent, Adult, Biomarkers, Collagen Type I, Estradiol, Exercise physiology, Female, Humans, Menstrual Cycle physiology, Parathyroid Hormone, Young Adult, Progesterone, Running physiology
- Abstract
This study examined potential fluctuations in bone metabolic markers across the menstrual cycle both at rest and after a 30-min bout of continuous running at 80% of V̇O
2max . Resting and post-exercise (0, 30, 90 min) sclerostin, parathyroid hormone (PTH), carboxy-terminal cross-linking telopeptide of type I collagen (β-CTXI), and procollagen type 1 N propeptide (PINP) were assessed in 10 eumenorrheic women (age: 21 ± 3 y, BMI: 23.2 ± 3.0 kg. m2 ) during the mid- to late-follicular (FP: day 8.0 ± 1.4) and mid-luteal (LP: day 22.0 ± 2.5) phases of the menstrual cycle. Ovulation was determined using ovulation kits and daily measurement of oral body temperature upon awakening. Menstrual cycle phase was subsequently confirmed by measurement of plasma estradiol and progesterone. On average, resting estradiol concentrations increased from 46.3 ± 8.9 pg·mL-1 in the FP to 67.3 ± 23.4 pg·mL-1 in the LP (p = 0.015), and resting progesterone increased from 4.12 ± 2.36 ng·mL-1 in the FP to 11.86 ± 4.49 ng·mL-1 in the LP (p < 0.001). At rest, there were no differences between menstrual cycle phases in sclerostin (FP: 260.1 ± 135.0 pg·mL-1 ; LP: 303.5 ± 99.9 pg·mL-1 ; p = 0.765), PTH (FP: 0.96 ± 0.64 pmol·L-1 ; LP: 0.79 ± 0.44 pmol·L-1 ; p = 0.568), β-CTXI (FP: 243.1 ± 158.0 ng·L-1 ; LP: 202.4 ± 92.3 ng·L-1 ; p = 0.198), and PINP (FP: 53.6 ± 8.9 μg·L-1 ; LP: 66.2 ± 20.2 μg·L-1 ; p = 0.093). Main effects for time (p < 0.05) were shown in sclerostin, PTH, β-CTXI and PINP, without phase or interaction effects. Sclerostin increased from pre- to immediately post-exercise (45%; p = 0.007), and so did PTH (43%; p = 0.011), both returning to resting concentrations 30 min post-exercise. β-CTXI decreased from pre- to post-exercise (20%; p = 0.027) and was still below its pre-exercise concentrations at 90 min post-exercise (17%; p = 0.013). PINP increased immediately post-exercise (29%; p < 0.001), returning to resting concentrations at 30 min post-exercise. These results demonstrate no effect of menstrual cycle phase on resting bone marker concentrations or on the bone metabolic marker response to intense exercise., (© 2022. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)- Published
- 2022
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40. Acute Effects of Milk vs. Carbohydrate on Bone Turnover Biomarkers Following Loading Exercise in Young Adult Females.
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Prowting JL, Skelly LE, Kurgan N, Fraschetti EC, Klentrou P, and Josse AR
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Dairy products and impact exercise have previously been identified to be independently beneficial for bone mineral properties, however, it is unknown how the combination of these two osteogenic interventions may alter acute bone turnover. Using a randomized crossover design, we compared the acute effects of consuming milk vs. an isoenergetic carbohydrate control beverage on bone biomarkers following loading exercise. Thirteen healthy female participants (Age = 20.3 ± 2.3y; BMI = 21.0 ± 1.1 kg/m
2 ) consumed either 550 mL of 0% skim white milk (MILK) or 52.7 g of maltodextrin in 550 mL of water (CHO), both 5 min and 1 h following completion of a combined plyometric (198 impacts) and resistance exercise (3-4 sets/exercise, 8-12 reps/set, ∼75% 1-RM) bout. Venous blood samples were obtained pre-exercise, and 15 min, 75 min, 24 h and 48 h post-exercise to assess serum concentrations of bone resorption biomarkers, specifically carboxyl-terminal crosslinking telopeptide of type I collagen (CTX), receptor activator nuclear factor kappa-β ligand (RANKL), and sclerostin (SOST), as well as bone formation biomarkers, specifically osteoprotegerin (OPG) and osteocalcin (OC). When absolute biomarker concentrations were examined, there were no interaction or group effects for any biomarker, however, there were main time effects ( p < 0.05) for RANKL, SOST, and OC, which were lower, and the OPG: OPG/RANKL ratio, which was higher at 75 min post-exercise compared with baseline in both conditions. In addition to assessing absolute biomarker concentrations at specific timepoints, we also evaluated the relative (% change) cumulative post-exercise response (75 min to 48 h) using an area under the curve (AUC) analysis. This analysis showed that the relative post-exercise CTX response was significantly lower in the MILK compared to the CHO condition ( p = 0.03), with no differences observed in the other biomarkers. These results show that while milk does not appear to alter absolute concentrations of bone biomarkers compared to CHO, it may attenuate relative post-exercise bone resorption (i.e., blunt the usual catabolic response to exercise)., Competing Interests: AJ reports consultant/speaker fees from Dairy Farmers of Canada. LS reports salary support from Dairy Management Inc. For projects outside the present work. AJ and PK report grant funding from Dairy Farmers of Canada, Dairy Management Inc., and non-financial support from Danone and Parmalat. LS reports grant funding from Dairy Farmers of Canada. The remaining 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 © 2022 Prowting, Skelly, Kurgan, Fraschetti, Klentrou and Josse.)- Published
- 2022
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41. Intensified training in adolescent female athletes: a crossover study of Greek yogurt effects on indices of recovery.
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McKinlay BJ, Wallace PJ, Olansky S, Woods S, Kurgan N, Roy BD, Josse AR, Falk B, and Klentrou P
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- Adolescent, Athletes, C-Reactive Protein analysis, Carbohydrates, Creatine Kinase, Cross-Over Studies, Female, Humans, Inflammation, Insulin-Like Growth Factor I, Interleukin-10, Athletic Performance physiology, Soccer physiology, Yogurt
- Abstract
Background: During a period of intensified exercise (e.g. training/identification camps), often undertaken by competitive youth athletes, the maintenance of muscle function and peak performance can become challenging due to an accumulation of fatigue. The provision of post-exercise dairy protein in adults has been previously shown to accelerate recovery; however, its efficacy in youth athletes is currently unknown. Therefore, the purpose of this study was to examine the effects of increased dairy protein consumption with plain Greek yogurt (GY) on performance and recovery indices during an intensified soccer training camp in adolescent female soccer players., Methods: Thirteen players (14.3 ± 1.3 years) participated in a randomized, double blinded, crossover design study where they received 3 servings/day of either GY (~115 kcal, 17 g protein, ~11.5 g carbohydrates) or an isoenergetic carbohydrate control (CHO, ~115 kcal, 0.04 g protein, ~28.6 g carbohydrates) during two 5-day soccer-specific training camps. Performance was assessed before and after each training camp. Fasted, morning, creatine kinase (CK), insulin-like growth factor-1 (IGF-1), C-reactive protein (CRP), interleukin 6 (IL6), interleukin 10 (IL10) and tumor necrosis factor-α (TNFα) were measured in plasma pre- and post-training., Results: Training led to decrements in counter-movement jump ( p = 0.01), broad jump ( p = 0.04) and aerobic capacity ( p = 0.006), with no effect of GY. A significant increase in anti-inflammatory cytokine IL10 was observed from pre- to post-training in GY (+26% [ p = 0.008]) but not in CHO ( p = 0.89). CRP and CK increased (+65% [ p = 0.005] and +119% [ p ≤ 0.001], respectively), while IGF-1 decreased (-34% [ p ≤ 0.001]) from pre- to post-training with no difference between conditions., Conclusions: These results demonstrate that consumption of GY did not offer any added recovery benefit with respect to measures of performance and in the attenuation of exercise-induced muscle damage above that achieved with energy-matched carbohydrate in this group of young female soccer players. However, regular consumption of GY may assist with the acute anti-inflammatory response during periods of intensified training in adolescent athletes., Competing Interests: No potential conflict of interest was reported by the author(s)., (© 2022 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group.)
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- 2022
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42. Subcutaneous adipose tissue sclerostin is reduced and Wnt signaling is enhanced following 4-weeks of sprint interval training in young men with obesity.
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Kurgan N, Islam H, Matusiak JBL, Baranowski BJ, Stoikos J, Fajardo VA, MacPherson REK, Gurd BJ, and Klentrou P
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- Humans, Male, Obesity therapy, Subcutaneous Fat metabolism, Wnt Signaling Pathway, High-Intensity Interval Training, beta Catenin metabolism
- Abstract
Sclerostin is a Wnt/β-catenin antagonist, mainly secreted by osteocytes, and most known for its role in reducing bone formation. Studies in rodents suggest sclerostin can also regulate adipose tissue mass and metabolism, representing bone-adipose tissue crosstalk. Exercise training has been shown to reduce plasma sclerostin levels; but the effects of exercise on sclerostin and Wnt/β-catenin signaling specifically within adipose tissue has yet to be examined. The purpose of this study was to examine subcutaneous WAT (scWAT) sclerostin content and Wnt signaling in response to exercise training in young men with obesity. To this end, 7 male participants (BMI = 35 ± 4; 25 ± 4 years) underwent 4 weeks of sprint interval training (SIT) involving 4 weekly sessions consisting of a 5-min warmup, followed by 8 × 20 s intervals at 170% of work rate at VO
2peak , separated by 10 s of rest. Serum and scWAT were sampled at rest both pre- and post-SIT. Despite no changes in serum sclerostin levels, we found a significant decrease in adipose sclerostin content (-37%, p = 0.04), an increase in total β-catenin (+52%, p = 0.03), and no changes in GSK3β serine 9 phosphorylation. There were also concomitant reductions in serum TNF-α (-0.36 pg/ml, p = 0.03) and IL-6 (-1.44 pg/ml, p = 0.05) as well as an increase in VO2peak (+5%, p = 0.03) and scWAT COXIV protein content (+95%, p = 0.04). In conclusion, scWAT sclerostin content was reduced and β-catenin content was increased following SIT in young men with excess adiposity, suggesting a role of sclerostin in regulating human adipose tissue in response to exercise training., (© 2022 The Authors. Physiological Reports published by Wiley Periodicals LLC on behalf of The Physiological Society and the American Physiological Society.)- Published
- 2022
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43. High-intensity interval training or resistance training versus usual care in men with prostate cancer on active surveillance: a 3-arm feasibility randomized controlled trial.
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Papadopoulos E, Gillen J, Moore D, Au D, Kurgan N, Klentrou P, Finelli A, Alibhai SMH, and Santa Mina D
- Subjects
- Adult, Aged, Biomarkers blood, Body Composition, Cardiorespiratory Fitness, Feasibility Studies, Humans, Inflammation blood, Male, Middle Aged, Muscle Strength, Patient Compliance, Prostatic Neoplasms physiopathology, Prostatic Neoplasms psychology, Self Report, High-Intensity Interval Training, Insulin-Like Growth Factor Binding Protein 3 blood, Insulin-Like Growth Factor I metabolism, Prostatic Neoplasms blood, Resistance Training, Watchful Waiting
- Abstract
This study assessed the feasibility of a phase II randomized controlled trial of high-intensity interval training (HIIT), resistance training (RT), and usual care (UC) in men with prostate cancer (PCa) on active surveillance and evaluated changes in clinically relevant outcomes. Eighteen men undergoing active surveillance for PCa were randomized to HIIT ( n = 5), RT ( n = 7), or UC ( n = 6). Exercise participants attended 2 supervised sessions weekly and were instructed to complete 1 home-based session weekly for 8 weeks. UC participants were provided with physical activity guidelines. Feasibility was met for attendance, compliance, and retention, but not recruitment. HIIT increased leg press (mean: +8.2 kg, 95% CI 1.1 to 15.3) from baseline to 8 weeks. RT increased seated row (mean: +11.7 kg, 95% CI 6.1 to 17.3), chest press (mean: +10.4 kg, 95% CI 5.3 to 15.5), leg press (mean: +13.1 kg, 95% CI 5.9 to 20.3), serum insulin-like binding protein-3 (IGFBP-3) (mean: +400.0 ng/mL, 95% CI 94.5 to 705.5), and decreased interferon-γ (mean: -3.1 pg/mL, 95% CI -5.7 to -0.4). No changes were observed in the UC group. HIIT and RT may be effective strategies for improving muscle strength; however, only RT may increase serum IGFBP-3. Strategies that can enhance recruitment in men on active surveillance are important prior to conducting a phase II trial. Trial registration number: ClinicalTrials.gov number NCT04266262. Novelty: High-intensity interval training or resistance training are feasible during active surveillance for prostate cancer. Resistance training may suppress the tumour-promoting effects of insulin-like growth factor-I (IGF-I) via increased expression of IGFBP-3.
- Published
- 2021
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44. Circulating Levels of Bone Markers after Short-Term Intense Training with Increased Dairy Consumption in Adolescent Female Athletes.
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Klentrou P, McKee K, McKinlay BJ, Kurgan N, Roy BD, and Falk B
- Abstract
Thirteen female adolescent soccer players (14.3 ± 1.3 years) participated in a cross-over, double-blind trial examining the effects of Greek yogurt (GY) consumption on bone biomarkers during 5 days of intense soccer training. The study took place over two intervention weeks, which consisted of a pre-training assessment day, 5 training days, and a post-training assessment day. Participants completed the GY condition and a carbohydrate isocaloric placebo control pudding condition (CHO) in random order, 4 weeks apart. Morning, fasted, resting blood samples were collected pre- and post-training in each condition. Total osteocalcin (tOC), undercarboxylated osteocalcin (unOC), C-terminal telopeptide of type 1 collagen (CTX), osteoprotegerin (OPG), and receptor activator nuclear factor kappa-β ligand (RANKL) were measured in serum. The results showed no effects for time (pre- to post-training) or condition, and no interaction for tOC, CTX, OPG, RANKL, and the OPG/RANKL ratio. A time-by-condition interaction ( p = 0.011) was observed in unOC, reflecting a post-training decrease in the GY, but not the CHO condition (-26% vs. -3%, respectively). However, relative unOC (% of tOC) decreased post-training (-16%), with no differences between conditions. These findings suggest that short-term high-impact intense training had no direct catabolic impact on bone metabolism, with GY adding no benefit beyond that of the isocaloric CHO control pudding.
- Published
- 2021
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45. Cytokine concentrations in saliva vs. plasma at rest and in response to intense exercise in adolescent athletes.
- Author
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Beigpoor A, McKinlay BJ, Kurgan N, Plyley MJ, O'Leary D, Falk B, and Klentrou P
- Subjects
- Adolescent, Athletes, Child, Female, Humans, Interleukin-10, Interleukin-6, Male, Rest, Tumor Necrosis Factor-alpha, Cytokines analysis, Cytokines blood, Saliva chemistry, Swimming physiology
- Abstract
Background: Salivary measures are advantageous in conducting large paediatric studies involving repeated measures. However, research measuring salivary cytokines in youth is limited., Aim: Compare salivary with plasma concentrations of inflammatory cytokines at rest and following exercise in adolescent swimmers (21 male, 22 female)., Methods: Following collection of resting saliva and blood samples, participants performed a bout of high-intensity interval swimming, with samples taken again ∼15 min post-swimming and analysed for interleukin-6 (IL-6), interleukin 10 (IL-10), and tumour necrosis factor-alpha (TNF-α)., Results: Resting IL-10 was significantly lower, while IL-6 and TNF-α were significantly higher in saliva compared with plasma. IL-10 increased from pre- to post-swimming in plasma, but less so in saliva (51% vs. 29%; p = 0.02). TNF-α decreased post-swimming in saliva, but not in plasma (-27% vs -1%; p = 0.01). IL-6 decreased post-swimming in saliva compared with plasma (-21% vs. -3%; p = 0.06). Intraclass correlation coefficients (ICC) revealed no association between salivary and plasma IL-6 and TNF-α, while IL-10 showed a weak correlation only at rest (ICC = 0.39; p = 0.05)., Conclusions: Differences in concentrations and exercise responses, along with weak correlations, suggest that salivary cytokine levels are not an accurate representation of blood cytokine levels, and should not be used as a surrogate measure in paediatric studies.
- Published
- 2021
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46. Neutral Effect of Increased Dairy Product Intake, as Part of a Lifestyle Modification Program, on Cardiometabolic Health in Adolescent Girls With Overweight/Obesity: A Secondary Analysis From a Randomized Controlled Trial.
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Skelly LE, Barbour-Tuck EN, Kurgan N, Calleja M, Klentrou P, Falk B, and Josse AR
- Abstract
Background: The presence of obesity and some cardiometabolic disease risk factors in childhood and adolescence track into adulthood. Intake of dairy products has been shown to be inversely related to adiposity and cardiometabolic variables in youth. However, limited research has examined cardiometabolic disease risk factors following increased dairy product consumption as part of a lifestyle modification intervention in youth with overweight/obesity. This secondary analysis aimed to determine whether 12 weeks of increased dairy consumption, as part of a lifestyle modification program, affects cardiometabolic variables in adolescent females (range: 10-18 years) with overweight/obesity (BMI > 85th centile). Methods: Participants were randomized into two groups: higher dairy intake (RDa; four servings/day [to reflect previous Canada's Food Guide recommendations]; n = 23) or low dairy intake (LDa; 0-2 servings/day; n = 23). Both RDa and LDa participated in a 12-week, eucaloric, lifestyle modification intervention consisting of exercise training, and nutritional counseling. Adiposity (percent body fat [%BF]), dietary intake, and measures of cardiometabolic health were measured pre- and post-intervention. Results: There were no significant changes over time within groups or differences over time between groups for triglycerides (TG), total cholesterol (TC), high-density lipoprotein cholesterol (HDL), TC/HDL ratio, low-density lipoprotein cholesterol (LDL), glucose, insulin, homeostatic model assessment of insulin resistance, adiponectin, and tumor necrosis factor alpha (TNF-α) (main effects of time and interactions, p > 0.05). Leptin decreased over the 12-week lifestyle intervention in both groups (main effect of time, p = 0.02). After combining the groups ( n = 46), significant correlations were found between change in %BF and change in some cardiometabolic variables (HDL [ r = -0.40], TC/HDL ratio [ r = 0.42], LDL [ r = 0.36], and TNF-α [ r = 0.35], p < 0.05). After controlling for change in dairy product intake, the correlations were unchanged. Conclusion: Our findings demonstrate that increased dairy product consumption, as part of a lifestyle modification, weight management intervention, had a neutral effect on cardiometabolic disease risk factors in adolescent females with overweight/obesity. Change in dairy product intake did not influence the relationships between change in adiposity and change in cardiometabolic variables. Future research designed to primarily assess the effect of increased dairy product consumption on cardiometabolic disease risk factors in this population is warranted. Clinical Trial Registration: Clinicaltrials.gov; NCT#02581813., Competing Interests: AJ, BF, and PK report grants for this research from Dairy Farmers of Canada, US National Dairy Council (Dairy Management Inc.), non-financial support from Danone and Parmalat during the conduct of the study; AJ reports personal fees from Dairy Farmers of Canada Grant Review Board outside the submitted work. LS and EB-T report some salary support from the US National Dairy Council grant. The remaining 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 © 2021 Skelly, Barbour-Tuck, Kurgan, Calleja, Klentrou, Falk and Josse.)
- Published
- 2021
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47. Cytokines, Adipokines, and Bone Markers at Rest and in Response to Plyometric Exercise in Obese vs Normal Weight Adolescent Females.
- Author
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Kurgan N, McKee K, Calleja M, Josse AR, and Klentrou P
- Subjects
- Adolescent, Biomarkers blood, Bone Remodeling physiology, Female, Humans, Adipokines blood, Cytokines blood, Exercise physiology, Osteocalcin blood, Parathyroid Hormone blood, Pediatric Obesity blood
- Abstract
Background: In adults, excess adiposity has been associated with low-grade, chronic inflammation and compromised bone health, but less is known about these linkages in children. The purpose of this study was to compare the circulating levels of inflammatory cytokines, adipokines, osteokines, and bone markers at rest and in response to plyometric exercise between obese and normal weight adolescent females., Methods: Ten normal weight (BMI = 21.3 ± 2) and 10 obese (BMI = 32.9 ± 4), postmenarcheal females, aged 13-17 years, performed one bout of plyometric exercise (5 circuits; 120 jumps). Blood samples were taken at rest, 5 min, 1 h, and 24 h post-exercise. Tumor necrosis factor alpha (TNF-α), interleukin 6 (IL-6), insulin, leptin, osteocalcin, carboxy-terminal telopeptide (CTX), sclerostin, and parathyroid hormone (PTH) were measured in serum., Results: Cytokines were not different between groups at rest or over time with IL-6 increasing (+31%; p = 0.04) 5 min post-exercise and TNF-α decreasing (-9%; p = 0.001) 1 h post-exercise. Insulin and leptin were higher in the obese compared to the normal weight females. In both groups, insulin significantly increased 5 min post-exercise but remained elevated 1 h post-exercise only in the obese group. Leptin did not change in response to exercise. Osteocalcin was lower in the obese group across time and increased (+12%; p = 0.02) 24 h post-exercise in both groups. CTX was similar between groups at rest and decreased (-24%; p < 0.001) 1 h post-exercise. Sclerostin was similar between groups at rest, but there was a significant interaction reflecting a significant increase (+29%; p = 0.04) 5 min post-exercise in the obese group and a non-significant decrease (-13%; p = 0.08) in normal weight controls. PTH increased 5 min post-exercise, dropped 1 h post-exercise to lower than pre-exercise, and returned to baseline 24 h post-exercise in both groups., Conclusion: Obese adolescent females from our study had no evidence of resting inflammation or differences in bone resorption but show blunted bone formation when compared to normal weight controls. The direction and temporal changes in inflammatory cytokines, adipokines, and bone turnover markers to exercise were similar in both groups, reflecting an overall bone anabolic response for most biomarkers, except sclerostin, which increased only in the obese females immediately post-exercise, suggesting a different systemic regulation of sclerostin depending on adiposity., 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 Kurgan, McKee, Calleja, Josse and Klentrou.)
- Published
- 2020
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48. Effects of Post-Exercise Whey Protein Consumption on Recovery Indices in Adolescent Swimmers.
- Author
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McKinlay BJ, Theocharidis A, Adebero T, Kurgan N, Fajardo VA, Roy BD, Josse AR, M Logan-Sprenger H, Falk B, and Klentrou P
- Subjects
- Adolescent, Athletes, Child, Creatine Kinase blood, Cytokines blood, Dietary Carbohydrates administration & dosage, Female, Humans, Male, Muscle, Skeletal, Dietary Supplements, Myalgia prevention & control, Sports Nutritional Physiological Phenomena, Swimming, Whey Proteins administration & dosage
- Abstract
Purpose : This study examined the effect of whey protein consumption following high-intensity interval swimming (HIIS) on muscle damage, inflammatory cytokines and performance in adolescent swimmers. Methods : Fifty-four swimmers (11-17 years-old) were stratified by age, sex and body mass to a whey protein (PRO), isoenergetic carbohydrate (CHO) or a water/placebo (H
2 O) group. Following baseline blood samples (06:00 h) and a standardised breakfast, participants performed a maximal 200 m swim, followed by HIIS. A total of two post-exercise boluses were consumed following HIIS and ~5 h post-baseline. Blood and 200 m performance measurements were repeated at 5 h, 8 h and 24 h from baseline. Muscle soreness was assessed at 24 h. Creatine kinase (CK), interleukin-6 (IL-6), interleukin-10 (IL-10) and tumor necrosis factor-alpha (TNF-α) were measured in plasma. Results : No difference in 200 m swim performance was observed between groups. CK activity was elevated at 5 h compared to baseline and 24 h and at 8 h compared to all other timepoints, with no differences between groups. Muscle soreness was lower in PRO compared to H2 O ( p = 0.04). Anti-inflammatory IL-10 increased at 8 h in PRO, while it decreased in CHO and H2 O. Conclusions : Post-exercise consumption of whey protein appears to have no additional benefit on recovery indices following HIIS compared to isoenergetic amounts of carbohydrate in adolescent swimmers. However, it may assist with the acute-inflammatory response.- Published
- 2020
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49. The role of phospholamban and GSK3 in regulating rodent cardiac SERCA function.
- Author
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Hamstra SI, Whitley KC, Baranowski RW, Kurgan N, Braun JL, Messner HN, and Fajardo VA
- Subjects
- Animals, Calcium metabolism, Calcium Signaling genetics, Cardiomyopathies genetics, Cardiomyopathies metabolism, Cardiomyopathies pathology, Gene Expression Regulation genetics, Heart Failure metabolism, Heart Failure pathology, Humans, Myocardial Contraction genetics, Calcium-Binding Proteins genetics, Glycogen Synthase Kinase 3 genetics, Heart Failure genetics, Sarcoplasmic Reticulum Calcium-Transporting ATPases genetics
- Abstract
Cardiac contractile function is largely mediated by the regulation of Ca
2+ cycling throughout the lifespan. The sarco(endo)plasmic reticulum Ca2+ ATPase (SERCA) pump is paramount to cardiac Ca2+ regulation, and it is well established that SERCA dysfunction pathologically contributes to cardiomyopathy and heart failure. Phospholamban (PLN) is a well-known inhibitor of the SERCA pump and its regulation of SERCA2a-the predominant cardiac SERCA isoform-contributes significantly to proper cardiac function. Glycogen synthase kinase 3 (GSK3) is a serine/threonine kinase involved in several metabolic pathways, and we and others have shown that it regulates SERCA function. In this mini-review, we highlight the underlying mechanisms behind GSK3's regulation of SERCA function specifically discussing changes in SERCA2a and PLN expression and its potential protection against oxidative stress. Ultimately, these recent findings that we discuss could have clinical implications in the treatment and prevention of cardiomyopathies and heart failure.- Published
- 2020
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50. Buckling of thin skew isotropic plate resting on Pasternak elastic foundation using extended Kantorovich method.
- Author
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Hassan AHA and Kurgan N
- Abstract
The extended Kantorovich method (EKM) is implemented to numerically solve the elastic buckling problem of thin skew (parallelogram) isotropic plate under in-plane loading resting on the Pasternak elastic foundation. EKM has never been applied to this problem before. Investigation of the EKM accuracy and convergence is conducted. Formulations are based on classical plate theory (CPT). Stability equations and boundary conditions terms are derived from the principle of the minimum total potential energy using the variational calculus expressed in an oblique coordinate system. The resulting two sets of ordinary differential equations are solved numerically using the Chebfun package in MATLAB software. In-plane compression and shear loads are considered along with various boundary conditions and aspect ratios. Results are compared to the analytical and numerical solutions found in the literature, and to the finite element solutions obtained using ANSYS software. The effects of the skew angle, stiffness of elastic foundation, and aspect ratio on the buckling load are also investigated. For plates with zero skew angle, i.e. rectangular plates, with various boundary conditions and aspect ratios under uniaxial and biaxial loading resting on elastic foundation, the single-term EKM is found accurate. However, more terms are needed as the skew angle gets bigger. The multi-term EKM is found accurate in the analysis of rectangular and skew plates with various boundary conditions and aspect ratios under uniaxial, biaxial, and shear loading resting on elastic foundation. Using EKM in buckling analysis of thin skew plates is found simple, accurate, and rapid to converge., (© 2020 Published by Elsevier Ltd.)
- Published
- 2020
- Full Text
- View/download PDF
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