19 research outputs found
Дослідження протигерпетичної активності похідних амінопропанолу-2.
Introduction. Chemotherapy and chemoprophylaxis are some of the main and often the only possible ways to effective control of viral infections. Therefore, the study of antiviral properties of new substances with the known chemical structure is one of the main ways to create new antiviral agents.The aim of the study – to research the antiherpes activity of new aminopropanol-2 derivatives against the herpes simplex virus (HSV) antigenic type 1, strain VC.Research Methods. Antiherpes activity was determined in 8 aminopropanol-2 derivatives: norbornyl containing substance (compound No. 51), substance with cyclic substituents in alkoxi group (compound No. 48), substances with alicyclic substituents in alkoxi group (compounds No. 46, 47, 49, 50, 52 and 53). Evaluation of antiherpes activity of the studied compounds was performed in vitro on cell culture VNK (growing culture of hamster kidney). Ability to reduce of virus infectious titer and chemotherapeutic index (HTI) of the studied compounds was determined.Results and Discussion. It is established that the compound No. 53 inhibits HSV-I reproduction in 2 lg ID50 at a concentration of 1.56 µg/ml. HTI of compound No. 53 is equal to 64, which describes it as an effective inhibitor of HSV-I reproduction. Some antiherpes action in compounds No. 46, 47 and 51 was identified also, their HTI were 8, 4 and 4 respectively. Substances No. 48, 49, 50 and 52 do not show the antiherpes action.Conclusions. Among all tested aminopropanol-2 derivatives the compound No. 53 with clear antiherpes properties was determined. Compound No. 53 belongs to the substances with alicyclic substituents in alkoxi group and has such chemical formula: 1-(2-methyl-3-butinox)-3-(2.2.6.6-tetramethyl piperidine)-2-propanol hydrochloride. Compound No. 53 as alicyclic substituent in alkoxy group contains 2-methyl-3-butene, and amine moiety of this substance contains the radical 2.2.6.6 – tetramethylpiperidine. The obtained results will be useful in establishing the natural relationships "structure-activity", also it can be used to create active compounds with certain characteristics.Вступление. В связи с тем, что химиотерапия и химиопрофилактика являются одними из главных, а часто и единственно возможными средствами эффективной борьбы с вирусными инфекциями, исследование соединений нового синтеза с известной формулой на предмет выявления их противовирусных свойств остается одним из основных направлений при создании новых противовирусных препаратов. Цель исследования – изучить противогерпетическую активность новых соединений аминопропанола-2 в отношении вируса герпеса простого (HSV)1-го антигенного типа, штамм VC.Методы исследования. Определяли противогерпетическое действие 8 производных аминопропанола-2, среди которых вещество № 51 относилось к норборнилсодержащим соединениям, вещество № 48 – к соединениям с циклическими заместителями в алкоксигруппе, вещества № 46, 47, 49, 50, 52 и 53 относились к соединениям с алициклическими заместителями в алкоксигруппе. Противогерпетическую активность исследуемых веществ оценивали in vitro на культуре клеток ВНК (перевиваемая культура клеток почки хомяка) по снижению инфекционного титра вируса и путем определения их химиотерапевтического индекса (ХТИ).Результаты и обсуждение. Установлено, что вещество № 53 угнетает репродукцию вируса HSV-I на 2 lg ID50 в концентрации 1,56 мкг/мл, а ХТИ этого соединения равняется 64, что характеризует его как эффективный ингибитор репродукции HSV-I. Также выявлено незначительную противогерпетическую активность веществ № 46, 47 и 51, о чем свидетельствуют показатели их ХТИ (8, 4 и 4 соответственно). Вещества № 48, 49, 50 и 52 не имеют противогерпетического действия.Выводы. Среди исследованных производных аминопропанола-2 идентифицировано соединение 1-(2-метил-3-бутинокси)-3-(2,2,6,6-тетраметил пиперидино)-2-пропанол гидрохлорид (вещество № 53), которое проявляет выраженое противогерпетическое действие. По химической структуре вещество № 53 относится к группе соединений с алициклическими заместителями в алкоксигруппе, где алициклическим заместителем является 2-метил-3-бутен, а аминный фрагмент этого вещества содержит радикал 2,2,6,6-тетраметилпиперидин. Полученные результаты будут полезны при установлении закономерных взаимосвязей “структура – активность” и могут быть использованы при создании активных соединений с определенными характеристикамиВступ. З огляду на те, що хіміотерапія та хіміопрофілактика є одними з головних, а часто і єдино можливими засобами ефективної боротьби з вірусними інфекціями, дослідження сполук нового синтезу з відомою формулою стосовно виявлення їх противірусних властивостей залишається одним з основних шляхів створення нових противірусних препаратів.Мета дослідження – вивчити протигерпетичну активність нових сполук амінопропанолу-2 відносно вірусу простого герпесу (HSV) 1-го антигенного типу, штам VC.Методи дослідження. Визначали дію протигерпетичну у 8 похідних амінопропанолу-2, серед яких сполука № 51 належала до норборніловмісних речовин, сполука № 48 – до речовин із циклічними замісниками в алкоксигрупі, сполуки № 46, 47, 49, 50, 52 і 53 належали до речовин з аліциклічними замісниками в алкоксигрупі. Протигерпетичну активність досліджуваних речовин оцінювали in vitro на культурі клітин ВНК (перещеплювана культура клітин нирки хом’яка) за зниженням інфекційного титру вірусу та шляхом визначення їх хіміотерапевтичного індексу (ХТІ). Результати й обговорення. Встановлено, що сполука № 53 пригнічує репродукцію вірусу HSV-I на 2 lg ID50 в концентрації 1,56 мкг/мл, а ХТІ цієї речовини дорівнює 64, що характеризує її як ефективний інгібітор репродукції HSV-I. Також виявлено деяку протигерпетичну сполук № 46, 47 та 51, про що свідчать показники їх ХТІ (8, 4 і 4 відповідно). Речовини № 48, 49, 50 та 52 не мають протигерпетичної дії.Висновки. Серед досліджених похідних амінопропанолу-2 ідентифіковано сполуку 1-(2-метил-3-бутинокси)-3-(2,2,6,6-тетраметил піперидино)-2-пропанол гідрохлорид (сполука № 53), що проявляє виражену протигерпетичну дію. За хімічною структурою сполука № 53 належить до групи речовин з аліциклічними замісниками в алкоксигрупі, де аліциклічним замісником є 2-метил-3-бутен, а амінний фрагмент цієї речовини містить радикал 2,2,6,6-тетраметилпіперидин. Отримані результати будуть корисними при встановленні закономірних взаємозв’язків “структура – активність” та можуть бути використані при створенні активних сполук з певними характеристиками.
Comparative performance of selected variability detection techniques in photometric time series
Photometric measurements are prone to systematic errors presenting a
challenge to low-amplitude variability detection. In search for a
general-purpose variability detection technique able to recover a broad range
of variability types including currently unknown ones, we test 18 statistical
characteristics quantifying scatter and/or correlation between brightness
measurements. We compare their performance in identifying variable objects in
seven time series data sets obtained with telescopes ranging in size from a
telephoto lens to 1m-class and probing variability on time-scales from minutes
to decades. The test data sets together include lightcurves of 127539 objects,
among them 1251 variable stars of various types and represent a range of
observing conditions often found in ground-based variability surveys. The real
data are complemented by simulations. We propose a combination of two indices
that together recover a broad range of variability types from photometric data
characterized by a wide variety of sampling patterns, photometric accuracies,
and percentages of outlier measurements. The first index is the interquartile
range (IQR) of magnitude measurements, sensitive to variability irrespective of
a time-scale and resistant to outliers. It can be complemented by the ratio of
the lightcurve variance to the mean square successive difference, 1/h, which is
efficient in detecting variability on time-scales longer than the typical time
interval between observations. Variable objects have larger 1/h and/or IQR
values than non-variable objects of similar brightness. Another approach to
variability detection is to combine many variability indices using principal
component analysis. We present 124 previously unknown variable stars found in
the test data.Comment: 29 pages, 8 figures, 7 tables; accepted to MNRAS; for additional
plots, see http://scan.sai.msu.ru/~kirx/var_idx_paper
Inflows, Outflows, and a Giant Donor in the Remarkable Recurrent Nova M31N 2008-12a? - Hubble Space Telescope Photometry of the 2015 Eruption
The recurrent nova M31N 2008-12a experiences annual eruptions, contains a near-Chandrasekhar mass white dwarf, and has the largest mass accretion rate in any nova system. In this paper, we present Hubble Space Telescope (HST) WFC3/UVIS photometry of the late decline of the 2015 eruption. We couple these new data with archival HST observations of the quiescent system and Keck spectroscopy of the 2014 eruption. The late-time photometry reveals a rapid decline to a minimum luminosity state, before a possible recovery / re-brightening in the run-up to the next eruption. Comparison with accretion disk models supports the survival of the accretion disk during the eruptions, and uncovers a quiescent disk mass accretion rate of the order of , which may rise beyond during the super-soft source phase - both of which could be problematic for a number of well-established nova eruption models. Such large accretion rates, close to the Eddington limit, might be expected to be accompanied by additional mass loss from the disk through a wind and even collimated outflows. The archival HST observations, combined with the disk modeling, provide the first constraints on the mass donor; , , and K, which may be consistent with an irradiated M31 red-clump star. Such a donor would require a system orbital period days. Our updated analysis predicts that the M31N 2008-12a WD could reach the Chandrasekhar mass in < 20 kyr
M31N 2008-12a - the remarkable recurrent nova in M31: Pan-chromatic observations of the 2015 eruption
The Andromeda Galaxy recurrent nova M31N 2008-12a had been observed in eruption ten times, including yearly eruptions from 2008-2014. With a measured recurrence period of days (we believe the true value to be half of this) and a white dwarf very close to the Chandrasekhar limit, M31N 2008-12a has become the leading pre-explosion supernova type Ia progenitor candidate. Following multi-wavelength follow-up observations of the 2013 and 2014 eruptions, we initiated a campaign to ensure early detection of the predicted 2015 eruption, which triggered ambitious ground and space-based follow-up programs. In this paper we present the 2015 detection; visible to near-infrared photometry and visible spectroscopy; and ultraviolet and X-ray observations from the Swift observatory. The LCOGT 2m (Hawaii) discovered the 2015 eruption, estimated to have commenced at Aug. UT. The 2013-2015 eruptions are remarkably similar at all wavelengths. New early spectroscopic observations reveal short-lived emission from material with velocities km s, possibly collimated outflows. Photometric and spectroscopic observations of the eruption provide strong evidence supporting a red giant donor. An apparently stochastic variability during the early super-soft X-ray phase was comparable in amplitude and duration to past eruptions, but the 2013 and 2015 eruptions show evidence of a brief flux dip during this phase. The multi-eruption Swift/XRT spectra show tentative evidence of high-ionization emission lines above a high-temperature continuum. Following Henze et al. (2015a), the updated recurrence period based on all known eruptions is d, and we expect the next eruption of M31N 2008-12a to occur around mid-Sep. 2016
Breaking the habit - the peculiar 2016 eruption of the unique recurrent nova M31N 2008-12a
Since its discovery in 2008, the Andromeda galaxy nova M31N 2008-12a has been observed in eruption every single year. This unprecedented frequency indicates an extreme object, with a massive white dwarf and a high accretion rate, which is the most promising candidate for the single-degenerate progenitor of a type-Ia supernova known to date. The previous three eruptions of M31N 2008-12a have displayed remarkably homogeneous multi-wavelength properties: (i) From a faint peak, the optical light curve declined rapidly by two magnitudes in less than two days; (ii) Early spectra showed initial high velocities that slowed down significantly within days and displayed clear He/N lines throughout; (iii) The supersoft X-ray source (SSS) phase of the nova began extremely early, six days after eruption, and only lasted for about two weeks. In contrast, the peculiar 2016 eruption was clearly different. Here we report (i) the considerable delay in the 2016 eruption date, (ii) the significantly shorter SSS phase, and (iii) the brighter optical peak magnitude (with a hitherto unobserved cusp shape). Early theoretical models suggest that these three different effects can be consistently understood as caused by a lower quiescence mass-accretion rate. The corresponding higher ignition mass caused a brighter peak in the free-free emission model. The less-massive accretion disk experienced greater disruption, consequently delaying re-establishment of effective accretion. Without the early refueling, the SSS phase was shortened. Observing the next few eruptions will determine whether the properties of the 2016 outburst make it a genuine outlier in the evolution of M31N 2008-12a
No Neon, but Jets in the Remarkable Recurrent Nova M31N 2008-12a?—Hubble Space Telescope Spectroscopy of the 2015 Eruption
The 2008 discovery of an eruption of M31N 2008-12a began a journey on which the true nature of this remarkable recurrent nova continues to be revealed. M31N 2008-12a contains a white dwarf (WD) close to the Chandrasekhar limit, accreting at a high rate from its companion, and undergoes thermonuclear eruptions that are observed yearly and may even be twice as frequent. In this paper, we report on Hubble Space Telescope Space Telescope Imaging Spectrograph ultraviolet spectroscopy taken within days of the predicted 2015 eruption, coupled with Keck spectroscopy of the 2013 eruption. Together, this spectroscopy permits the reddening to be constrained to E(B-V)=0.10+/- 0.03. The UV spectroscopy reveals evidence for highly ionized, structured, and high-velocity ejecta at early times. No evidence for neon is seen in these spectra, however, but it may be that little insight can be gained regarding the composition of the WD (CO versus ONe)
GoldenBullet in a Nutshell
Internet and Web technology starts to penetrate many aspects of our daily life. Its importance as a medium for business transactions will grow exponentially during the next years
GoldenBullet: Automated Classification of Product Data in E-commerce
Internet and Web technology starts to penetrate many aspects of our daily life. Its importance as a medium for business transactions will grow exponentially during the next years. In terms of the involved market volume the B2B area will hereby be the most interesting area. Also it will be the place, where the new technology will lead to drastic changes in established customer relationships and business models. B2B market places provide new kinds of services to their clients. Simple 1-1 connections are getting replaced by n-m relationships between customers and vendors. However, this new flexibility in electronic trading also generates serious challenges for the parties that want to realize it. The main problem here is caused by the heterogeneity of information descriptions used by vendors and customers. Intelligent solutions that help to mechanize the process of structuring, classifying, aligning, and personalizing are a key requisite for successfully overcoming the current bottlenecks of B2B electronic commerce. In this paper, we describe a system called GoldenBullet that applies techniques from information retrieval and machine learning to the problem of product data classification. The system helps to mechanize an important and labor-intensive task of content management for B2B Ecommerce
THE INFLUENCE OF ADEMOL ON OOCYTE AND THEIR FOLICULAR CELLS
Today àdemoles influence on functional ovaries remains unexplored. Data about the treatment of àdemol on oocytes and cells of their follicular environment are absent. The purpose of the work is to evaluate the effect of àdemol treatment on oocytes and cells of their follicular environment in mice, namely oocytes meiotic maturation, the viability of cells of their follicular environment in animals aged 8 weeks and 8 months. The study was conducted using 24 non-pregnant females of linear white mice for 8 weeks and 24 non-pregnant females with linear white mice at the age of 8 months. Two series of experiments were conducted. SERIES 1: àdemol treatment was once a day intraperitoneally (at a dose of 5 mg/kg). Animal groups: I - control (8 weeks) (n = 4); ²² - ademol (8 weeks) (n = 6); III control (8 months) (n = 4); IV - ademol (8 months) (n = 6). Material (ovaries) for further research was taken 1 hour after ademol treatment. SERIES 2: àdemol treatment was once a day 4 times intraperitoneally (at a dose of 5 mg/kg). Animal groups: I - control (8 weeks) (n = 8); ²² - 8 ademol (weeks) (n = 6); III control (8 months) (n = 8); IV - ademol (8 months) (n = 6). The material (ovaries) for further research was taken 1 hour after the last (fourth) treatment of ademol. No effect on oocytes and cells of follicular environments was detected after 1 h after single treatment of ademol in animals of all experimental groups (at the age of 8 weeks and 8 months). It has been established that the four-fold treatment of ademol leads to a 2,13-times increase in the number of oocytes successfully passing metaphase I and 2,03 times that reaching the metaphase II, as well as leads to an increase in 1,45 times the number of alive cells of the follicular environment, as well as a reduction of 1,75 times apoptotic and 1,47 times necrotic cells for mice age eight months. In this work we found that in eight-month-old mice, the treatment of ademol leads to an increase of number of oocytes successfully passing meiotic maturation, as well as an increase in number of alive, apoptotic and necrotic cells of the follicular environment. The data we have received expand the information about the effect of ademol treatment in experimental animals. Further research is needed to establish the mechanisms of action of àdemol on oocytes and cells of their follicular environment. It seems probable for us to clarify the possibility NO-dependent and antioxidant effects of àdemol using experimental models of immune-mediated damage. Conclusion. A four times treatment of ademol leads to an increase in the percentage of oocytes that successfully pass both phases of meiotic maturation and the proportion of living cells of the cells of the follicular environment, as well as a decrease in the percentage of apoptotic and necrotic cells of the follicular environment in eight months old mice