108 research outputs found
Cross-border clusters as the form of transplantation of institutions into economic area of postmodernity
Досліджено механізм трансплантації інститутів мережевої економіки як необхідний чинник зростання конкурентоспроможності єврорегіонів в умовах євроінтеграції України. На основі інституційного підходу обґрунтовано, що постіндустріальна економіка еволюціонувала в систему взаємодіючих інститутів формують новий економічний простір постмодерну в транскордонному вимірі. Розглянуто сутність та внутрішні взаємозв'язки транскордонного кластеру як чинника зростання конкурентоспроможності єврорегіону.The mechanism of transplantation of network economics institutions is studied as the necessary growth factor of competitive capacity of the European regions in terms of European integration. By means of institutional approach it is justified that postindustrial economics evolved into the system of interlocking institutions, forming a new economic area of postmodernity in cross-border dimension, in which such virtual resources of development are necessary as: information, innovations, ways of communication, knowledge and other institutions of postindustrial society. The subject and internal connections of cross-border cluster is investigated as the growth factor of competitive capacity of the European region in terms of tightening the integration process and the necessity of enhancement of the role of peripheral regions economics under cross-border cooperation.
It is concluded that a new postmodern reality lies in the combination of postindustrial production with the network construction of economic area, involving transplantation of the institutions by means of self-organization of hybrid network clusters on both sides of the border that becomes the factor of integration and free circulation of the funds in the European regions
Directed search for diuretics among 6-substituted pteridine-2,4,7(1H,3H,8H)-triones
Directed search for biologically active compounds among
heterocycles still remains a relevant area of medical chemistry. Among the significant number of heterocyclic compounds,
pteridines deserve special attention. Among the above-mentioned ones the drugs with antitumor, antimicrobial, antiviral,
diuretic and other types of biological action are known. Nevertheless, 6-substituted pteridine-2,4,7(1H,3H,8H)-triones,
which are structurally similar to triamterene (6-phenylpteridine-2,4,7-triamine) – a diuretic with potassium-sparing
action are interesting objects for search for diuretics. All the more, they are characterized by prototropic tautomerism,
able to form hydrogen and donor-acceptor bonds with various ligands, and it is likely that these structural features will
provide their diuretic effect. The aim of the study is the directed search for diuretics among 6-substituted pteridine2,4,7(1H,3H,8H)-triones using in silico and in vivo methodology and elucidation of the probable mechanism of action.
1-methyl-3-R-6- (2-oxo-2-aryl- (hetaryl-) ethyl) pteridine-2,4,7(1H,3H,8H)-triones were selected to study the effect on
renal excretory function. and 1-methyl-3-R-6- (2-hydroxy-2-aryl- (hetaryl-) ethyl) pteridine-2,4,7(1H,3H,8H)-triones.
Directed search for compounds that affect the excretory function of the kidneys of rats was conducted by the conventional
method of E.B. Berkhin with water load. The content of creatinine, sodium, potassium and chlorides in blood and urine
plasma was determined by biochemical methods using standard test kits of NPV "Philisit-Diagnostics" (Ukraine) and
calculations were performed according to generally accepted methods. Research of the probable mechanism was
conducted by flexible molecular docking, as an approach of finding molecules with affinity to a specific biological target.
Macromolecular data were downloaded from the Protein Data Bank (PDB) namely, the crystal structures of Human
carbonic anhydrase II (PDB ID – 3HS4) and epithelial sodium channel (ENaC) (PDB ID – 4NTX). Studies of the effect
of the synthesized compounds on the excretory function of the kidneys of rats showed that 1-methyl-3-R-6- (2-oxo-2-aryl-
(hetaryl-) ethyl) pteridine-2,4,7(1H,3H,8H)-triones containing 4-fluorophenyl, 2,4-difluorophenyl, 4-chlorophenyl
fragments in the molecule increase diuresis by the second hour by 27.3-70.1% compared with the control group.
According to the results of the impact on daily diuresis, it was found that the most active was 1-methyl-6- (2-oxo-2-phenyl)
ethyl) pteridine-2,4,7(1H,3H,8H)-triones, which increased daily diuresis by 168.1%, exceeding the effect of
Hydrochlorothiazide (41.8%) and Triamterene (49.1%). However, substituted 1-methyl-3-R-6- (2-hydroxy-2-aryl-
(hetaryl-) ethyl) pteridine-2,4,7(1H,3H,8H)-triones are inactive compounds. In-depth studies using biological tests and
molecular docking have suggested that 1-methyl-6- (2-oxo-2-aryl) ethyl) pteridine-2,4,7(1H,3H,8H)-triones 2.1, 2.5 and
2.6) probable mechanisms of diuretic action are disruption of sodium transport in the distal convoluted tubules, causing
sodium excretion and water loss and possibly inhibition of epithelial sodium channels that promote sodium uptake and potassium secretion in the distal convolutions and tubules, which implements potassium-sparing action. A well-founded
and developed strategy for the search for diuretics among 6-substituted pteridine-2,4,7(1H,3H,8H)-triones has identified
a number of effective compounds that by diuretic effect are superior to the reference drugs "Hydrochlorothiazide" and
"Triamterene". Importantly, the results of molecular docking suggested a mechanism of action of the compounds under
study, similar to thiazide diuretics. This action may be related to the tautomerism of these compounds and, as a
consequence, their ability to form coordination bonds with the zinc cation and the additional interaction of halogens in
the active site of CA II. It was possible to detect the presence of potassium-sparing action, probably due to the ability to
inhibit epithelial sodium channels (ENaC). The obtained results substantiate the further purposeful search for potential
diuretics among this class of compound
In silico and in vivo screening of triamterene synthetic analogues as promising diuretics
The modification of lead-compound aimed to the
increasing of activity, decrement of toxicity or improvement of selectivity is one of the most important methods used for
elaboration of novel medications. Natural compounds, approved or investigational drugs or just compounds with proved
biological activity could be the lead-compound. Often the chemical modification of lead compounds is directed at the
enhancement of ligand-biological target interactions. Abovementioned approach, namely structural modification of known drug
triamterene was used for purposeful search for novel diuretics. The preliminary prognostication of ligand-target interactions
and affinity levels allow to reduce quantity of experimental animals, synthesis, and pharmacological studies costs. Conducted
studies revealed the series of promising 6,7-disubstituted pteridine-2,4(1H,3H)-diones with diuretic activity that comparable
with pharmacological effect of triamterene. Aim – purposeful search for promising diuretics among structural analogues of
triamterene that includes preliminary in silico studies, synthesis and in vivo screening of novel compounds for diuretic activity.
Methods used: organic synthesis, physicochemical methods of analysis of organic compounds (NMR 1
H-spectroscopy,
chromato-mass spectrometry, elemental analysis). Prediction of affinity for a biological target, prediction of toxicity and
lipophilicity of the combinatorial library, which was created on the basis of the drug triamterene, was carried out using
computer services. Studies of compounds that affect the excretory function of the kidneys of rats were performed according to
the generally accepted method of E.B. Berkhin with water load. Research of the probable mechanism was conducted by flexible
molecular docking, as an approach of finding molecules with affinity to a specific biological target. Macromolecular data were
downloaded from the Protein Data Bank (PDB) namely, the crystal structures of epithelial sodium channel (ENaC) ((PDB ID
– 6WTH). The substantiation of potential diuretics design was conducted by in silico methods (prediction of affinity, ligandenzyme interactions and pharmacokinetic characteristics). The structural modification of triamterene molecule was carried
out by replacing of amino-group in positions 2, 4 and 7 by others “pharmacophore” fragments. Abovementioned
transformation is aimed at the changing of ligand-enzyme interactions in active site, lipophility and toxicity. Synthesis of 6,7-
disubstituted pteridine-2,4(1H,3H)-diones was conducted by condensation 5,6-diamino-2-oxo-(thioxo-)-2,3-dihydropyrimidin4(1H)-ones with carbonyl-containing compounds or oxocarboxylic acids. The further modification of obtained compounds was
performed by alkylation, hydrazinolysis and nucleophilic addition/elimination. The structure of obtained compounds was
proven by elemental analysis, chromato-mass and 1
H NMR-spectral analysis. The studies of synthesized compounds effect on
excretion function of kidneys allowed to detect series of promising structural analogues of triamterene that exceed it in
pharmacological activity by 27.3-99.0%. The “structure-biological activity” relationship was discussed and perspective of the
further search of diuretics among abovementioned compounds were shown. The design of new biologically active compounds
with diuretic activity was performed using in silico methodologies and realized by structural modification of the well-known
diuretic triamterene. Traditional organic synthesis was used for preparation of target compounds, in vivo experiments wereused to detect compounds with significant biological activity. Several effective compounds were identified among pteridines,
which exceed the reference drug triamterene in terms of daily diuresis. The obtained results substantiate further purposeful
search, in-depth research on experimental pathologies and study of the mechanism of action of potential diuretics among this
class of compound
Design and search for prospective diuretics (CA II Inhibitors) among aroylhydrazones of esters quinone oxime using in silico and in vivo methodology
The design and search for new selective inhibitors of CA II with a better pharmacological profile, which would cause minimal electrolyte disturbances in the body, remains an urgent problem of medical chemistry and pharmacology today. It is important that the discovered new classes of inhibitors do not always contain the main “pharmacophoric” function (sulfamide), which is characteristic of “classic” drugs (Acetazolamide, Methazolamide, Ethoxzolamide, Dorzolamide and others), but are derivatives of phenols, polyamines, coumarins/thiocoumarins, ureas, thioureas, hydroxamates, etc. These molecules also bind in the active site of the enzyme, but do not interact directly with the catalytic zinc ion or interact through zinc-coordinated water molecules/hydroxide ion. However, this leads to an increase in their selectivity and, as a result, pharmacological action. Continuing the search for compounds that affect urination, we were interested in aroylhydrazones of esters of quinone oxime. Firstly, they are characterized by certain structural features (dynamic and geometric isomerism); secondly, they exhibit redox properties; thirdly, the presence of aromatic fragments makes it possible to create a voluminous combinatorial library for analysis. These compounds are ligands in complexation reactions, and an additional increase in the number of hydrogen acceptors in the molecule due to structural modification will improve ligand-enzymatic interactions with carbonic anhydrase (CAII) and, as a result, reveal new promising diuretics. The aim – design and search for potential diuretics (CA II inhibitors) among aroylhydrazones of esters of quinone oxime using in silico, traditional synthesis and in vivo methodologies. Methods of organic synthesis, physico-chemical methods of analysis of organic compounds (NMR 1H-spectroscopy, elemental analysis). Prediction of affinity to the biological target, prediction of toxicity and lipophilicity of the combinatorial library of benzohydrazides O-aroyl esters of quinone oxime using computer services. The study of compounds affecting the excretory function of rat kidneys was carried out according to the generally accepted method of E.B.Berkhin with water load. The investigation of the probable mechanism was carried out using flexible molecular docking, as an approach to search for molecules that have affinity for human carbonic anhydrase type II (CA II). Macromolecular data of the crystal structure of CA II (PDB ID – 3HS4) were downloaded from the Protein Data Bank (PDB). The design was developed and the search for diuretic agents among benzohydrazides of O-aroyl esters of quinone oximes was developed using in silico methods (prediction of affinity, lipophilicity, toxicity and enzyme-ligand interactions), traditional organic synthesis, and in vivo methods (effect on excretory function of rat kidneys). The synthesis of benzohydrazides of O-aroyl esters of quinone oxime was carried out by the interaction of aroylhydrazines with 4-[(aroylimino)]cyclohexa-2,5-dien-1-ones. The structure of the synthesized compounds was confirmed by elemental analysis and 1H NMR spectra. Studies of the effect of synthesized compounds on the excretory function of rat kidneys allowed us to identify a number of promising compounds among aroylhydrazones of quinonexime esters, which increase daily diuresis by 54.2-352.8% compared to the control group. At the same time, it was established that the most active was N'-(4-[(2-chlorobenzoyloxy)imino]cyclohexa-2,5-dien-1-ylidene)-3-nitrobenzohydrazide, which increased daily diuresis by 352.8% in comparison with the control group, while exceeding the effect of “Hydrochlorothiazide” (170.8%). The developed and implemented strategy for the search for diuretics among benzohydrazides of O-aroylesters of quinone oxime allowed the identification of an effective compound, which in terms of diuretic effect exceeds the comparison drug “Hydrochlorothiazide”. Visualization of the molecular docking of the active compounds showed that their geometry makes it difficult to place them in the pocket of the active site of CA II, but the pronounced diuretic effect can also be associated with their ability to form coordination bonds with the zinc cation. The obtained results justify the further targeted search for potential diuretics among this class of compounds for a more detailed understanding and study of the mechanism of action
N-arylsulfonyl-2-aroylamino-1,4- quinonе imines and their hydrogenated analogues: prediction of toxicity and prospects for use as diuretics
Continuing our research on compounds that affect
urination, we have become interested in N-arylsulfonyl-2-aroylamino-1,4-quinone imines, which combine a quinone matrix
with tolylsulfonamide and benzamide fragments with versatile biological activity in their structure, which has a promising
value in preventing development of pathological processes in kidneys. Therefore, the search for low-toxic compounds with
polyvector activity as a promising approach to the design of drug-like molecules has become an urgent aspect in this regard.
The aim of this work was to investigate N-arylsulfonyl-2-aroylamino-1,4-quinone imines and their hydrogenated analogues
as promising diuretic agents with antiradical and antibacterial activity using in silico, in vitro and in vivo methodologies.
The virtual laboratory of the ProTox-II site is used to predict the toxicity of molecules. The study of compounds affecting the
excretory function of the rat kidneys was carried out on 120 white Wistar rats according to the method of E.B. Berkhin under
conditions of water stress and spontaneous urination. The interaction of the synthesised compounds with 2,2-diphenyl-1-
picrylhydrazyl (DPPH) was used to study their antiradical activity in vitro. The antibacterial activity of the compounds was
studied on test cultures of the bacteria Escherichia coli, Staphylococcus aureus, Mycobacterium luteum and the fungi
Candida tenuis, Aspergillus niger by the method of serial dilutions in a liquid nutrient medium. Based on the results of the
calculation, it was predicted that N-arylsulfonyl-2-aroylamino-1,4-quinone imines (2) and their hydrogenated analogues (3)
have hepato-(immuno-, cyto-) toxicity, carcinogenicity (mutagenicity) similar to natural quinones and diuretics (toxicity class
IV). This class of compounds has been shown to have both stimulatory and inhibitory effects on diuresis under conditions of
water stress and spontaneous urination. At the same time, N-(5-methyl-6-oxo-3-(tosylimino)cyclohexa-1,4-dien-1-yl)benzamide
(2.3) was revealed to increase daily diuresis by 67.1% compared with the control, exceeding the effect of «Furosemide»
(22.2%). It was found that quinone imines (2.1-2.5) inhibited the formation of the DPPH radical by 25.99-40.09%, while their
hydrogenated analogues (3.1 and 3.2) – by 61.56% and 68.28%, respectively, and are more effective acceptors of radicals. The
microbiological screening revealed a number of promising compounds that inhibited the growth of S. aureus (compound 2.5,
MIC 62.5 μg/ml, MBC 125.0 μg/ml), M. luteum (3.1 and 3.2, MIC 31.2 μg/ml, MBC 62.5 μg/ml) and A. niger (2.1, 2.4 and 3.2,
MIC 31.2 μg/ml, MPC 62.5 μg/ml). According to the results of biological studies, among N-arylsulfonyl-2-aroylamino-1,4-
quinone imines and their hydrogenated analogues, compound 2.3 has been identified, which competes with «Furosemide» in
potency and has high antibacterial activity against S. aureus. Other compounds show moderate antiradical activity, high
antibacterial activity against M. luteum (2.1, 3.1) and antifungal activity against A. niger (2.1, 2.4, 3.2). The obtained results
support the further research for diuretics with polyvector activity within this class of compounds
N-arylsulfonyl-2-aroylamino-1,4-quinone imines and their hydrogenated analogues: prediction of toxicity and prospects for use as diuretics
Sokolova K.V., Podpletnia O.A., Konovalova S.O., Avdieienko A.P., Komarovska-Porokhniavets O.Z., Lubenets V.I., Kovalenko S.I. Continuing our research on compounds that affect urination, we have become interested in N-arylsulfonyl-2-aroylamino-1,4-quinone imines, which combine a quinone matrix with tolylsulfonamide and benzamide fragments with versatile biological activity in their structure, which has a promising value in preventing development of pathological processes in kidneys. Therefore, the search for low-toxic compounds with polyvector activity as a promising approach to the design of drug-like molecules has become an urgent aspect in this regard. The aim of this work was to investigate N-arylsulfonyl-2-aroylamino-1,4-quinone imines and their hydrogenated analogues as promising diuretic agents with antiradical and antibacterial activity using in silico, in vitro and in vivo methodologies. The virtual laboratory of the ProTox-II site is used to predict the toxicity of molecules. The study of compounds affecting the excretory function of the rat kidneys was carried out on 120 white Wistar rats according to the method of E.B. Berkhin under conditions of water stress and spontaneous urination. The interaction of the synthesised compounds with 2,2-diphenyl-1-picrylhydrazyl (DPPH) was used to study their antiradical activity in vitro. The antibacterial activity of the compounds was studied on test cultures of the bacteria Escherichia coli, Staphylococcus aureus, Mycobacterium luteum and the fungi Candida tenuis, Aspergillus niger by the method of serial dilutions in a liquid nutrient medium. Based on the results of the calculation, it was predicted that N-arylsulfonyl-2-aroylamino-1,4-quinone imines (2) and their hydrogenated analogues (3) have hepato-(immuno-, cyto-) toxicity, carcinogenicity (mutagenicity) similar to natural quinones and diuretics (toxicity class IV). This class of compounds has been shown to have both stimulatory and inhibitory effects on diuresis under conditions of water stress and spontaneous urination. At the same time, N-(5-methyl-6-oxo-3-(tosylimino)cyclohexa-1,4-dien-1-yl)benzamide (2.3) was revealed to increase daily diuresis by 67.1% compared with the control, exceeding the effect of «Furosemide» (22.2%). It was found that quinone imines (2.1-2.5) inhibited the formation of the DPPH radical by 25.99-40.09%, while their hydrogenated analogues (3.1 and 3.2) – by 61.56% and 68.28%, respectively, and are more effective acceptors of radicals. The microbiological screening revealed a number of promising compounds that inhibited the growth of S. aureus (compound 2.5, MIC 62.5 μg/ml, MBC 125.0 μg/ml), M. luteum (3.1 and 3.2, MIC 31.2 μg/ml, MBC 62.5 μg/ml) and A. niger (2.1, 2.4 and 3.2, MIC 31.2 μg/ml, MPC 62.5 μg/ml). According to the results of biological studies, among N-arylsulfonyl-2-aroylamino-1,4-quinone imines and their hydrogenated analogues, compound 2.3 has been identified, which competes with «Furosemide» in potency and has high antibacterial activity against S. aureus. Other compounds show moderate antiradical activity, high antibacterial activity against M. luteum (2.1, 3.1) and antifungal activity against A. niger (2.1, 2.4, 3.2). The obtained results support the further research for diuretics with polyvector activity within this class of compounds
Guideline for diagnostic, prevention and treatment of postmenopausal osteoporosis
Background.Postmenopausal osteoporosis (PMO), which is developed due the estrogen deficiency in women after menopause, is the most common type of systemic osteoporosis. The latest Ukrainian recommendation for its management requires revision due to new data from high-quality research performed in recent years. Thepurposewas to develop a guideline on the diagnosis, prevention, and treatment of PMO based on an analytical analysis of modern literary sources in order to improve the awareness of the medical community of Ukraine. Methodology. To develop the guideline, an expert group of 13 leading Ukrainian scientists of various specialties was created who conducted a thorough review of modern literature on this topic, assessed the level of existing evidence using the GRADE system, proposed and voted on 15 recommendations of the guideline. Results. The guideline contains chapters on diagnosis and differential diagnosis of PMO, assessment of the osteoporotic fracture risk, the role of bone turnover markers in the management of PMO, and modern strategies of antiosteoporotic treatment.Conclusions. The Ukrainian guideline on the diagnosis, prevention, and treatment of PMO, which contains 15 main recommendations, created on the basis of a thorough analysis and synthesis of modern literature data, is an important tool for the management of PMO and is recommended by Ukrainian Association of Osteoporosis for use in Ukrainian medical community
Measurement of double beta decay of 100Mo to excited states in the NEMO 3 experiment
The double beta decay of 100Mo to the 0^+_1 and 2^+_1 excited states of 100Ru
is studied using the NEMO 3 data. After the analysis of 8024 h of data the
half-life for the two-neutrino double beta decay of 100Mo to the excited 0^+_1
state is measured to be T^(2nu)_1/2 = [5.7^{+1.3}_{-0.9}(stat)+/-0.8(syst)]x
10^20 y. The signal-to-background ratio is equal to 3. Information about energy
and angular distributions of emitted electrons is also obtained. No evidence
for neutrinoless double beta decay to the excited 0^+_1 state has been found.
The corresponding half-life limit is T^(0nu)_1/2(0^+ --> 0^+_1) > 8.9 x 10^22 y
(at 90% C.L.).
The search for the double beta decay to the 2^+_1 excited state has allowed
the determination of limits on the half-life for the two neutrino mode
T^(2nu)_1/2(0^+ --> 2^+_1) > 1.1 x 10^21 y (at 90% C.L.) and for the
neutrinoless mode T^(0nu)_1/2(0^+ --> 2^+_1) > 1.6 x 10^23 y (at 90% C.L.).Comment: 23 pages, 7 figures, 4 tables, submitted to Nucl. Phy
Results of the BiPo-1 prototype for radiopurity measurements for the SuperNEMO double beta decay source foils
The development of BiPo detectors is dedicated to the measurement of
extremely high radiopurity in Tl and Bi for the SuperNEMO
double beta decay source foils. A modular prototype, called BiPo-1, with 0.8
of sensitive surface area, has been running in the Modane Underground
Laboratory since February, 2008. The goal of BiPo-1 is to measure the different
components of the background and in particular the surface radiopurity of the
plastic scintillators that make up the detector. The first phase of data
collection has been dedicated to the measurement of the radiopurity in
Tl. After more than one year of background measurement, a surface
activity of the scintillators of (Tl) 1.5
Bq/m is reported here. Given this level of background, a larger BiPo
detector having 12 m of active surface area, is able to qualify the
radiopurity of the SuperNEMO selenium double beta decay foils with the required
sensitivity of (Tl) 2 Bq/kg (90% C.L.) with a six
month measurement.Comment: 24 pages, submitted to N.I.M.
Spectral modeling of scintillator for the NEMO-3 and SuperNEMO detectors
We have constructed a GEANT4-based detailed software model of photon
transport in plastic scintillator blocks and have used it to study the NEMO-3
and SuperNEMO calorimeters employed in experiments designed to search for
neutrinoless double beta decay. We compare our simulations to measurements
using conversion electrons from a calibration source of and show
that the agreement is improved if wavelength-dependent properties of the
calorimeter are taken into account. In this article, we briefly describe our
modeling approach and results of our studies.Comment: 16 pages, 10 figure
- …