66 research outputs found

    Creation of Kink and Antikink Pairs Forced By Radiation

    Full text link
    The interaction between kink and radiation in nonlinear one-dimensional real scalar field is investigated. The process of discrete vibrational mode excitation in ϕ4\phi^4 model is considered. The role of this oscillations in creation of kink and antikink is discussed. Numerical results are presented as well as some attempts of analytical explanations. An intriguing fractal structure in parameter space dividing regions with creation and without is also presented

    Norditerpenoids with selective anti-cholinesterase activity from the roots of Perovskia atriplicifolia Benth

    Get PDF
    Inhibition of cholinesterases remains one of a few available treatment strategies for neurodegenerative dementias such as Alzheimer's disease and related conditions. The current study was inspired by previous data on anticholinesterase properties of diterpenoids from Perovskia atriplicifolia and other Lamiaceae species. The acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibition by the three new natural compounds-(1R,15R)-1-acetoxycryptotanshinone (1), (1R)-1-acetoxytanshinone IIA (2), and (15R)-1-oxoaegyptinone A (3)-as well as, new for this genus, isograndifoliol (4) were assessed. Three of these compounds exhibited profound inhibition of butyrylcholinesterase (BChE) and much weaker inhibition of acetylcholinesterase (AChE). All compounds (1-4) selectively inhibited BChE (IC(50) = 2.4, 7.9, 50.8, and 0.9 µM, respectively), whereas only compounds 3 and 4 moderately inhibited AChE (IC(50) 329.8 µM and 342.9 µM). Molecular docking and in silico toxicology prediction studies were also performed on the active compounds. Natural oxygenated norditerpenoids from the traditional Central Asian medicinal plant P. atriplicifolia are selective BChE inhibitors. Their high potential makes them useful candidate molecules for further investigation as lead compounds in the development of a natural drug against dementia caused by neurodegenerative diseases

    Evaluation of the anti-inflammatory effects of synthesised tanshinone I and isotanshinone I analogues in zebrafish

    Get PDF
    During inflammation, dysregulated neutrophil behaviour can play a major role in a range of chronic inflammatory diseases, for many of which current treatments are generally ineffective. Recently, specific naturally occurring tanshinones have shown promising anti-inflammatory effects by targeting neutrophils in vivo, yet such tanshinones, and moreover, their isomeric isotanshinone counterparts, are still a largely underexplored class of compounds, both in terms of synthesis and biological effects. To explore the anti-inflammatory effects of isotanshinones, and the tanshinones more generally, a series of substituted tanshinone and isotanshinone analogues was synthesised, alongside other structurally similar molecules. Evaluation of these using a transgenic zebrafish model of neutrophilic inflammation revealed differential anti-inflammatory profiles in vivo, with a number of compounds exhibiting promising effects. Several compounds reduce initial neutrophil recruitment and/or promote resolution of neutrophilic inflammation, of which two also result in increased apoptosis of human neutrophils. In particular, the methoxy-substituted tanshinone 39 specifically accelerates resolution of inflammation without affecting the recruitment of neutrophils to inflammatory sites, making this a particularly attractive candidate for potential pro-resolution therapeutics, as well as a possible lead for future development of functionalised tanshinones as molecular tools and/or chemical probes. The structurally related β-lapachones promote neutrophil recruitment but do not affect resolution. We also observed notable differences in toxicity profiles between compound classes. Overall, we provide new insights into the in vivo anti-inflammatory activities of several novel tanshinones, isotanshinones, and structurally related compounds

    Environmental aspecst of oil and natural gas exploitation from Barnówko-Mostno-Buszewo deposit

    No full text
    W artykule przedstawiono analizę wpływów środowiskowych eksploatacji ropy naftowej i gazu ziemnego ze złoża BarnówkoMostno-Buszewo. Wykazano ograniczony, długotrwały wpływ na poszczególne komponenty środowiska. Opisano natężenie wpływu w czasie od odkrycia i udostępnienia złoża do chwili obecnej. Zwrócono uwagę na malejący trend wpływu w szczególności w odniesieniu do zwierzostanu.This paper presents an analysis of environmental impact of oil and natural gas exploitation from Barnówko-Mostno-Buszewo deposit. It was proved that this sustained impact on particular elements of environment is limited. Value of impact from the time of deposit development up to now was described. It was pay attention to decreased tendention of this environmental impact especially in relation to game population
    corecore