Search

Disturbances of lipid metabolism is a predisposing factor of cardiovascular diseases, which are accompanied by high mortality rates of the population - ischemic heart disease and ischemic stroke. Plant polysaccharides can be promising remedies for correction of lipid imbalance. In this regard, the aim of the study was to assess the hypolipidemic activity of polysaccharides isolated from the leaves of mistletoe. The test-object was the leaves of the white mistletoe (Viscum album L.) growing on the apple (Malus domestica Borkh.), and the pear (Pyrus communis L.). Polysaccharides (water-soluble polysaccharides and pectin substances) were quantitatively determined by the gravimetric method followed by reprecipitation from ethanol. The qualitative composition was evaluated by thin layer chromatography. Functional groups in polysaccharides were determined by titrimetric method. The hypolipidemic activity of the obtained polysaccharides was determined under oral administration at a dose of 100 mg / kg in Wistar rats by the change of the concentration of total cholesterol, triglycerides, LDL and HDL cholesterol. The change of the content of cholesteryl ester transfer protein and Niemann-Pick C1-Like1 protein was also determined. As a result, it was found that among the polysaccharides in the leaves of mistletoe, pectin substances are predominate, which belong to the group of low-esterified pectins. A significant content of free carboxyl groups in pectins from the leaves of mistletoe was also found. The study of hypolipidemic activity showed that, among the polysaccharides of mistletoe leaves, pectin substances exert a more pronounced effect on lipid metabolism, the use of which reduced the content of triglycerides, total cholesterol and LDL cholesterol with an increase in LDL cholesterol in rats, probably due to a decrease in the activity of cholesteryl ester transfer protein and Niemann-Pick C1-Like1 protein. At the same time, at the level of the trend, mistletoe pectins showed a higher level of activity than analogous compounds obtained from the leaves of host-plants. It should be noted that the severity of the pharmacological effect of mistletoe pectins did not depend on the host-plants. Thus, based on the obtained results, it can be assumed that pectins obtained from the mistletoe leaves can be a potentially effective and safety hypolipidemic agent.

Objective(s): Ischemic stroke is a disease with complex pathogenesis that requires timely and rational pharmacological intervention. One possible treatment for this condition may be to improve mitochondrial function as part of neuroprotective therapy.Materials and Methods: Cerebral ischemic damage was reproduced by middle cerebral artery permanent occlusion in Wistar male rats. 4-hydroxy-3,5-di-tretbutyl cinnamic acid was injected intraperitoneally in dose range of 25 mg/kg, 50 mg/kg, and 100 mg/kg. The time of administration was 3 days from the ischemia modeling. Further, changes in the rats’ cognitive functions in the Morris water maze test were evaluated, and the state of mitochondrial function in the hippocampal tissue was studied.Results: The study showed that the use of the studied compound dose-dependently improved mitochondrial function in the rat hippocampus. At doses of 20 mg/kg and 50 mg/kg, administration of the test substance increased citrate synthase activity by 55.1% (P

Objective(s): This work aimed to assess the effect of 10 new chromon-3-aldehyde derivatives on changes of mitochondrial function under the conditions of brain ischemia in rats. Materials and Methods: The work was executed on BALB/c male-mice (acute toxicity was evaluated) and male Wistar rats, which were used to model cerebral ischemia by permanent middle cerebral artery occlusion. The test-substances, 10 derivatives of chromon-3-aldehyde and the reference drug, N-acetylcysteine, were injected after modeling of ischemia for 3 days. After that, neurological symptoms, the area of cerebral infarction, and change in mitochondrial function were evaluated.Results: It was established that use of all chromon-3-aldehyde derivatives contributed to the recovery of mitochondrial function, which was reflected in enhanced ATP-generating activity, maximum respiration level, respiratory capacity, as well as reduction in the intensity of anaerobic reactions, apoptosis, and normalization of the mitochondrial membrane potential. The most pronounced changes were noted with the use of 6-acetyl substituted chromon-3-aldehyde derivative, the administration of which decreased neurological symptoms and size of brain necrosis area.Conclusion: The obtained data may indicate the most pronounced neurotropic effect in a number of test-objects has the 6-acetyl substituted derivative of chromon-3 aldehyde, realized by restoration of mitochondrial function, which may be the basis for further study of chromon-3-aldehyde derivatives.

With the exception of a few areas, Lake Michigan (LM) is an oligotrophic clear water body. It is predominantly in its littoral zone where ecology-relevant processes unfold due to a variety of natural and anthropogenic forcings arising from the watershed. However, the bottom influence there is strong enough to contaminate the at-satellite signal, thus impeding the remote sensing of water quality parameters within the coastal zone.A new bio-optical retrieval algorithm, based on a forward radiation transfer model, LM specific hydro-optical model and the multivariate optimization technique is developed for operational retrieval from satellite data of water quality parameters in lakes optically shallow areas. Application of the developed operational tool to processing MODIS-Aqua data (matching up the location and timing of in situ CPA and radiometric measurements) has convincingly shown its advantage over the OC4 performance in lacustrine optically shallow waters at all sampling stations.

Subsumed under the category of ocean colour (OC) data fusion tools, a new approach is developed to efficiently use the merits of two OC satellite sensors differing in their spatial and spectral resolution characteristics. The tool permits to combine high spectral but lower spatial resolution optical data from one satellite sensor with higher spatial resolution but lower spectral resolution data from the other one into an image possessing simultaneously both high spectral and high spatial resolution qualities.The developed algorithm employs the artificial intelligence tool: emulated/artificial neuron networks (AANs).The developed ANN algorithm performance and efficiency are demonstrated for Lake Michigan. The fusion was effected making use of multiband data from Sentinel-2 Multispectral Instrument (MSI) and MODIS-Aqua Moderate Resolution Imaging Spectroradiometer (MODIS) sensors. In this version MODIS-Aqua sensor is chosen as an analog of the Sentinel 3 OLCI, whose spectrometric and atmospheric corrected data are yet unavailable.The multi-sensor (MS) optical-optical fusion results have persuasively demonstrated the efficiency of the approach and its applicability to studies of natural water bodies of different optical complexity. It can be utilized in combination with any biogeochemical retrieval algorithms.In the case of retrieving water quality parameters (WQP) in optically shallow aquatic environments, the employment of the fusion tool developed is particularly promising as the bottom reflectance properties are frequently highly heterogeneous. Indeed, in such cases, remote sensing optical data acquired at simultaneously high spatial and spectral resolution are certainly more advantageous as compared to that acquired separately by two different sensors operating either at high spatial (but low spectral) or high spectral (but low spatial) resolution.For the retrieval of WQP in optically shallow waters (OSW) a special algorithm called Biooptical Retrieval Algorithm (BOREALI) - OSW was applied to study the eastern coastal zone of Lake Michigan. The application of both the OC fusion tool and our BOREALI-OSW algorithm permitted to document both interannual dynamics in WQPs as well as bottom substrate spatial heterogeneity in the target OSW area of Lake Michigan.

Озеро Мичиган относится к олиготрофному типу водоемов. Сильнее всего это проявляется в прибрежной зоне, где гидрологический режим вод формируется под действием различных природных и антропогенных факторов, протекающих на водосборной территории. Влияние дна достаточно сильно искажает регистрируемый спутником сигнал, препятствуя выполнению дистанционного зондирования параметров качества воды в этой части озера. Для извлечения из спутниковых снимков параметров качества воды в оптически мелких районах озера Мичиган был разработан новый биооптический алгоритм. Он основан на модели переноса излучения, гидрооптической модели озера Мичиган и многомерной оптимизации и позволяет получать оценку концентрации всех основных оптически активных веществ (ОАВ) в областях с различным типом дна: песок, ил, макрофиты (Chara или Cladophora) и известняковая галька. Тестирование алгоритма показало, что при очень низких концентрациях ОАВ (менее 0,01 в соответствующих единицах измерения) оптическое влияние дна становится незначительным при глубине около 20 метров. В воде с более высокими концентрациями взвешенного вещества (ВВ) и хлорофилла влияние дна становится неразличимым при глубине ~10 м. Тестирование чувствительности алгоритма к шуму показало, что чем меньше толщина исследуемого водного столба и чем выше альбедо дна, тем выше погрешность восстановления концентраций ОАВ. Например, в случае песчаного дна и глубины 5 м погрешность в 10 % при оценке альбедо дна приводит к ошибкам в 18, 28 и 10 % при восстановлении хлорофилла, ВВ и окрашенного растворенного органического вещества соответственно.

Emiliania huxleyi algae are known to enhance CO2 partial pressure in their ambient water, (pCO2)w. Thus, over such bloom areas, the atmospheric column-averaged dry air mole fraction of carbon dioxide (XCO2) is likely to increase, which has not been yet quantified on basin scales. Here we report on an Orbiting Carbon Observatory (OCO-2) satellite study of the influence of E. huxleyi blooms on XCO2 over the Black Sea. We established that concurrently with a (pCO2)w significant rise, there is an increase in the overlying XCO2 within the range ~1 to nearly 2 ppmv, which is on the order of the planetary annual increase of XCO2. As we found, (∆pCO2)w in the Back Sea and Subpolar and Polar seas are closely comparable. This strongly indicates that E. huxleyi blooms do weaken carbon sinks in the ocean on a large scale, which can be consequential for global climatology and marine biogeochemistry.

Blooms of a coccolithophore E. huxleyi are generally huge, occur annually and in the oceans of both Hemispheres. As a calcifying algal species, E. huxleyi is known to enhance the partial pressure of dissolved CO2 in surface ocean, thus reducing its ability to absorb atmospheric CO2.Here we report on the results of our satellite study of CO2 enhancement in the atmospheric column over E. huxleyi blooms in the North, Greenland, Iceland and Barents seas. The study is based on OCO-2 data, wind force and direction, and E. huxleyi bloom masks developed by us earlier. Eight case studies are discussed herein relating to the time period 2015-2018. The results obtained are strongly indicative that indeed the phenomenon of E. huxleyi blooms noticeably affect the carbon fluxes between the atmosphere and the surface ocean: the quantified enhancement of CO2 content in the atmospheric column over the bloom area in the six case studies proved to be in the range 0.6 -3.0 ppm. It is also shown that the magnitude of CO2 enhancement in the atmospheric column is significantly controlled by the air advection in the boundary layer.

The study was devoted to see the effect of ethylmethylhydroxypyridine succinate, acetylcysteine and choline alphoscerate on the mitochondrial function under condition of experimental cerebral ischemia in rat. An integrated approach was used with the assessment of changes in the respirometric and antiapoptotic functions of mitochondria. It was found that the application of the objects under study contributed to a decrease in the intensity of glycolysis and the restoration of aerobic glucose metabolism with an increase in ATP synthesis, as well as a decrease in the dissociation of reactions in mitochondrial complexes I, II, IV and V. In addition, the introduction of the studied drugs reduced the intensity of caspase-dependent and caspase-independent apoptosis reactions, which, together with the restoration of mitochondrial respiratory function, contributed to the decrease in the size of the necrosis zone of the brain. [ABSTRACT FROM AUTHOR]