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81.
INTRODUCTION: In order to be effective, treatment for osteoporosis must be long-term. Unfortunately, according to clinical trials and clinical practice the most frequent cause of patient resignation from the treatment is adverse reactions to the medications. In the case of bisphosphonates they are most frequently connected with irritant impact of the drug on gastrointestinal mucosa. The aim of our study was to answer the question whether alendronate tablets coated with a thin neutral layer may protect gastrointestinal mucosa from the irritant effects of the active substance. MATERIAL AND METHODS: Three types of tablets were administered into the cheek pouches of 18 Syrian hamsters (divided into 3 experimental groups: I, II, III) i.e. regular alendronate tablets, coated alendronate tablets and placebo. The tablets were applied for 4 minutes a day on 4 consecutive days. 24 hours after the last application, the animals were sacrificed and segments of buccal tissue were taken for histopathological examination. Oral tissue reaction was assessed using the microscopic examination grading system developed by ISO. The following adverse changes of the tissue were recorded: epithelial lesions, leucocyte infiltration, vascular congestion and oedema. Later the irritation index was calculated. RESULTS: The irritation index was 11.0 (moderately irritant), 0.0 and 0.0 (none-irritant), in each group respectively. CONCLUSION: It appears that the administration of the coated alendronate tablets reduces the frequency and intensity of the local adverse events from the gastrointestinal tract. 相似文献
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Michael Lauck Sergey V. Alkhovsky Yīmíng Bào Adam L. Bailey Zinaida V. Shevtsova Alexey M. Shchetinin Tatyana V. Vishnevskaya Matthew G. Lackemeyer Elena Postnikova Steven Mazur Jiro Wada Sheli R. Radoshitzky Thomas C. Friedrich Boris A. Lapin Petr G. Deriabin Peter B. Jahrling Tony L. Goldberg David H. O'Connor Jens H. Kuhn 《Journal of virology》2015,89(15):8082-8087
Simian hemorrhagic fever (SHF) is lethal for macaques. Based on clinical presentation and serological diagnosis, all reported SHF outbreaks were thought to be caused by different strains of the same virus, simian hemorrhagic fever virus (SHFV; Arteriviridae). Here we show that the SHF outbreaks in Sukhumi in 1964 and in Alamogordo in 1989 were caused not by SHFV but by two novel divergent arteriviruses. Our results indicate that multiple divergent simian arteriviruses can cause SHF. 相似文献
84.
Regan EA Mazur W Meoni E Toljamo T Millar J Vuopala K Bowler RP Rahman I Nicks ME Crapo JD Kinnula VL 《Free radical biology & medicine》2011,51(3):726-732
Extracellular superoxide dismutase (ECSOD) is the major superoxide-scavenging enzyme in the lung. Certain ECSOD polymorphisms are protective against COPD. We postulated that smokers and COPD subjects would have altered levels of ECSOD in the lung, airway secretions, and/or plasma. Lung tissue ECSOD was evaluated from nonsmokers, smokers, and subjects with mild to very severe COPD by Western blot, immunohistochemistry, and ELISA. ECSOD levels in plasma, bronchoalveolar lavage fluid (BALF), and induced-sputum supernatants were analyzed by ELISA and correlated with smoking history and disease status. Immunohistochemistry identified ECSOD in extracellular matrix around bronchioles, arteries, and alveolar walls, with decreases seen in the interstitium and vessels of severe COPD subjects using digital image analysis. Plasma ECSOD did not differ between COPD subjects and controls nor based on smoking status. ECSOD levels in induced sputum supernatants were elevated in current smokers and especially in COPD subjects compared to nonsmokers, whereas corresponding changes could not be seen in the BALF. ECSOD expression was reduced around vessels and bronchioles in COPD lungs. Substantial increases in sputum ECSOD in smokers and COPD is interpreted as an adaptive response to increased oxidative stress and may be a useful biomarker of disease activity in COPD. 相似文献
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Anna Nasulewicz Andrzej Mazur Adam Opolski 《Journal of trace elements in medicine and biology》2004,18(1):1-8
The formation of new blood vessels is the initial step in progressive tumour development and metastasis. The first stage in tumour angiogenesis is the activation of endothelial cells. Copper ions stimulate proliferation and migration of endothelial cells. It has been shown that serum copper concentration increases as the cancer disease progresses and correlates with tumour incidence and burden. Copper ions also activate several proangiogenic factors, e.g., vascular endothelial growth factor, basic fibroblast growth factor, tumour necrosis factor alpha and interleukin 1. This review concerns a brief introduction into the basics of tumour blood vessel development as well as the regulatory mechanisms of this process. The role of copper ions in tumour angiogenesis is discussed. The new antiangiogenic therapies based on a reduction of copper levels in tumour microenvironment are reviewed. 相似文献
87.
Chai W Breitenbucher JG Kwok A Li X Wong V Carruthers NI Lovenberg TW Mazur C Wilson SJ Axe FU Jones TK 《Bioorganic & medicinal chemistry letters》2003,13(10):1767-1770
Continued exploration of the SAR around the lead imidazopyridine histamine H(3) antagonist 1 has led to the discovery of several related series of heterocyclic histamine H(3) antagonists. The synthesis and SAR of indolizine, indole and pyrazolopyridine based compounds are now described. 相似文献
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Tian X Field T Mazur AW Ebetino FH Wos JA Crossdoersen D Pinney BB Sheldon RJ 《Bioorganic & medicinal chemistry letters》2005,15(11):2819-2823
A series of proline based melanocortin ligands has been developed on the basis of initial piperazine leads by using a more conformationally rigid scaffold. A number of these novel ligands showed significant binding affinity for MC3 and MC4 receptors. 相似文献
90.
Sarapuk J Klesczyńska H Bonarska D Bielecki K Trela Z Kordas L 《Zeitschrift für Naturforschung. C, Journal of biosciences》2005,60(5-6):421-426
A series of new aminoalkane- and aminofluorenephosphonates was synthesized for agrochemical application. The particular compounds had different alkyl substituents at the carbon, nitrogen and phosphorus atoms. Their pesticidal activity was checked by applying various experimental methods. These included the measurements of compounds' potency: to inhibit growth of cucumber and germination of white mustard seeds, to influence on the membrane potential of algae and to damage human erythrocyte membranes resulting in hemolysis. All the aminophosphonates were also used in equimolar binary mixtures with the well-known herbicide 2,4-dichlorophenoxyacetic acid (2,4-D), to check, if using such mixtures, the biological efficiencies found for particular compounds could be enhanced due to interactions between aminophosphonates and 2,4-D. The results demonstrated, that depending on the structural features of the compounds, the final effects differed from antagonistic, through additive to the most promising synergistic ones. However, the type of interaction between 2,4-D and the compounds studied found in different experiments was somewhat different. In order to estimate those effects various statistical methods were used (toxic unit method, isobole method). 相似文献