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The objective prerequisites for the transition from a strategy of confrontation to partnership relations in a competitive struggle for the consumer predetermine the need for a clear definition of such concepts as partnership relations and partner networks, since it is the partnership relations that provide market participants with more competitive advantages than they could have under condition of separate activities. The subject-matter of the study is a methodological solution to the problem of determining the effectiveness of establishing partnership relations and the formation of partner networks. After all, the effectiveness of the partner network can only be achieved if the effectiveness of the partnership relations is achieved. Therefore, the purpose of the article is to develop methodological approaches to determining the effectiveness of partner networks through the evaluation of partnership relations. In order to achieve this goal, the following research methods have been used in the paper: analysis and generalization of theoretical sources and scientific literature; abstract-logical method in the process of theoretical generalizations and formation of conclusions; prognostic and diagnostic; general scientific methods of analysis and synthesis. As a result of the research, the methodology of constructing a morphological matrix of the effectiveness of a partner network based on integrated indicators of the sustainability and reliability of partnership relations was proposed. In order to determine the components of sustainability, a methodology for calculating the integrated value of the sustainability index of the partnership relations is proposed. Herewith, five interrelated components are taken into account that are equally important for strategizing partnership relations such as economic, marketing, social, environmental sustainability, and also the sustainability of partner networks in general. The algorithm of quantitative and qualitative assessment of the reliability of partnership relations involves seven stages. In particular, the definition of requirements for the reliability of partnership relations within a certain partner network, the definition and adjustment of the indicators of the rating system of the reliability of partnership relations and their importance for the partner network, the formation of the rating of partnership relations by the values of the generalized index of reliability, rating partners within a specific partner network by the level of reliability. Therefore, the proposed expert methodical approach to the assessment of the reliability of partnership relations involves the calculation of three characteristics of reliability (partner, production and economic activities, partner network in general) and is an applied instrument set for a new solution to the scientific and applied problem in the area of formation and development of partner relations in the economy of Ukraine in order to ensure a high level of management of them in resource constraints.

The content of reduced glutathione (GSH) and activity of glutathione-dependent enzymes: glutathione peroxidase (GP) and glutathione-S-transferase (GT) in blood serum of rats in the diet supplemented of fine powder seeds Trigonella foenum graecum L. on the background of experimental obesity. It was established that the development of obesity in rats was accompanied by violation of homeostasis in the glutathione-dependent system of blood serum. It has been shown that animals on high-calorie diet-along 14 weeks had a decrease (1,2) in GSH concentration, a decline (1,7) in GP activity and the increase (1,7) of GT activity compared with control values. Addition to high-calorie diet 2% fine powder seeds Trigonella foenum graccum L. reduced the body weight gain by 21%, carried positive modulating effect on the content of GSH and GP, GT activity in animals with experimental obesity.

The migraine headache involves activation and central sensitization of the trigeminovascular pain pathway. The migraine aura is likely due to cortical spreading depression (CSD), a propagating wave of brief neuronal depolarization followed by prolonged inhibition. The precise link between CSD and headache remains controversial. Our objectives were to study the effect of CSD on neuronal activation in the periaqueductal grey matter (PAG), an area known to control pain and autonomic functions, and to be involved in migraine pathogenesis. Fos-immunoreactive nuclei were counted in rostral PAG and Edinger-Westphal nuclei (PAG-EWn bregma -6.5 mm), and caudal PAG (bregma -8 mm) of 17 adult male Sprague-Dawley rats after KCl-induced CSD under chloral hydrate anesthesia. Being part of a pharmacological study, six animals had received, for the preceding 4 weeks daily, intraperitoneal injections of lamotrigine (15 mg/kg), six others had been treated with saline, while five sham-operated animals served as controls. We found that the number of Fos-immunoreactive nuclei in the PAG decreased after CSD provocation. There was no difference between lamotrigine- and saline-treated animals. The number of CSDs correlated negatively with Fos-immunoreactive counts. CSD-linked inhibition of neuronal activity in the PAG might play a role in central sensitization during migraine attacks and contribute to a better understanding of the link between the aura and the headache., (Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.)

Aim: To investigate the role of protein tyrosine phosphorylation in gastric wound formation and repair following ulceration., Methods: Gastric lesions were induced in rats using restraint cold stress. To investigate the effect of oxidative and nitrosative cell stress on tyrosine phosphorylation during wound repair, total activity of protein tyrosine kinase (PTK), protein tyrosine phosphatase (PTP), antioxidant enzymes, nitric oxide synthase (NOS), 2',5'-oligoadenylate synthetase, hydroxyl radical and zinc levels were assayed in parallel., Results: Ulcer provocation induced an immediate decrease in tyrosine kinase (40% in plasma membranes and 56% in cytosol, P < 0.05) and phosphatase activity (threefold in plasma membranes and 3.3-fold in cytosol), followed by 2.3-2.4-fold decrease (P < 0.05) in protein phosphotyrosine content in the gastric mucosa. Ulceration induced no immediate change in superoxide dismutase (SOD) activity, 30% increase (P < 0.05) in catalase activity, 2.3-fold inhibition (P < 0.05) of glutathione peroxidase, 3.3-fold increase (P < 0.05) in hydroxyl radical content, and 2.3-fold decrease (P < 0.05) in zinc level in gastric mucosa. NOS activity was three times higher in gastric mucosa cells after cold stress. Following ulceration, PTK activity increased in plasma membranes and reached a maximum on day 4 after stress (twofold increase, P < 0.05), but remained inhibited (1.6-3-fold decrease on days 3, 4 and 5, P < 0.05) in the cytosol. Tyrosine phosphatases remained inhibited both in membranes and cytosol (1.5-2.4-fold, P < 0.05). NOS activity remained increased on days 1, 2 and 3 (3.8-, 2.6-, 2.2-fold, respectively, P < 0.05). Activity of SOD increased 1.6 times (P < 0.05) days 4 and 5 after stress. Catalase activity normalized after day 2. Glutathione peroxidase activity and zinc level decreased (3.3- and 2-fold, respectively, P < 0.05) on the last day. Activity of 2',5'-oligoadenylate synthethase increased 2.8-fold (P < 0.05) at the beginning, and 1.6-2.3-fold (P < 0.05) during ulcer recuperation, and normalized on day 5, consistent with slowing of inflammation processes., Conclusion: These studies show diverse changes in total tyrosine kinase activity in gastric mucosa during the recovery process. Oxidative and nitrosative stress during lesion formation might lead to the observed reduction in tyrosine phosphorylation during ulceration.

The goal of the presented work was the research of signal transduction mechanism in the rat gastric parietal cells under stomach ulcer conditions. In these cells activation of adenylate cyclase (increase of cAMP level and proteinkinase A activity) and phosphoinositide (increases [Ca2+]i; cGMP and phoshatidylinocitole levels; proteinkinase C, proteinkinase G, and calmodulin-dependent-proteinkinase activity) of signals pathway was shown. An increase of plasma membrane phospholipids (PC, PS, PE, PI, LPC) level was shown. Under conditions of influence of the stress factor the membran enzymes activity (H+, K+ -ATPase, 5'-AMPase, Na+, K+ -ATPase, Ca2+, Mg2+ -ATPase and H+, K+ -ATPase) was considerably increased. The intensification of lipid peroxidation processes in rats was demonstrated.

Acute cold stress caused lesions of gastric mucosa as a result of its attack by active oxygen and nitrogen compounds. The tissue regeneration is regulated by a cascade of tyrosine protein kinases. Gastric ulceration leads to a decrease in activity of tyrosine protein kinases and phosphatases, following by fall in phosphotyrosine content in proteins of plasma membranes of gastric mucosa cells. No changes in superoxide dismutase activity, slight increase in catalase activity, inhibition of glutathione peroxydase, significant increase in OH* content and decrease in zinc level were observed in the gastric mucosa cells of stressed rats. That increased oxidative damage can lead to inactivation of protein tyrosine phosphatases. Nitric oxide synthase activity was three times higher in gastric mucosa cells after the cold stress. That can promote nitrosylation of tyrosine residues. During following days nitric oxide synthase activity remains high. Superoxide dismutase is activated on the 4 and 5th day after the stress. Catalase activity normalizes after second day. Tyrosine protein kinase activity increases in membranes with maximum on the 4th day, and remains inhibited in cytosole. Tyrosine protein phosphatases keep inhibited as well. Gluthatione peroxydase activity and zinc level decreased on the 5th day. Obtained results can be the evidence of violations in signal transduction through protein tyrosine kinase cascades, due to the reduction in tyrosine phosphorylation, as a result of increase in the content of active oxygen and nitrogen species.