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СИНТЕЗ ТА АНТИБАКТЕРІАЛЬНІ ВЛАСТИВОСТІ 4-АМІНОФЕНІЛСУЛЬФОНАМІДУ, ІММОБІЛІЗОВАНОГО НА ПОЛІМЕРНОМУ НОСІЇ
The aim of the study. Today the immobilization of drugs to the polymeric carriers is increasingly important, due to the requirements to reduce the toxicity and prolongation of action of drugs. It is known the immobilization of the Sulfonamides on the Stiromali, methacrylate polymer matrices, wherein the pharmacologically active sulfanilamide easily remove from the polymer upon the application, by the acid hydrolysis. At the same time it is noted that immobilized sulfonamides derived from aminomethylated Styrene-divinylbenzene copolymer, although hydrolytic stability, maintain the antibacterial properties. In order to expand the examples of covalent immobilization of sulfonamides we synthesized 4-aminophenylsulfonamide on pellet and brous forms of styrene and divinylbenzene with SO2 as a bridging group.Materials and Methods. As a raw materials, we used the pellet macroporous sulfonated Styrene-divinylbenzene copolymer and copolymers Polypropylene and Styrene. Sulfochlorination of these copolymers the polymeric sulfonyl chlorides were obtained. This compounds were used in the reaction with 4-aminophenilsulfonamidom. Antibacterial properties of the material were studied by determining the growth inhibition zones of test E. coli K12 microorganism in a nutrient medium.Results and Discussion. The structure of synthesized immobilized 4-aminophenylsulfonamide proven by IR spectroscopy. It is shown that such materials exhibit a relatively pronounced antibacterial properties test culture of microorganisms E. coli K-12, in spite of their resistance to hydrolysis. Сonclusions. It is suggested that the hydrolysis of the materials takes place at a specic enzymatic catalysis in the medium with the release of 4-aminophenylsulfonamide.Мета роботи. У сучасних умовах іммобілізація лікарських засобів на полімерних носіях набуває все більшого значення, що пов’язане з вимогами до зменшення токсичності та пролонгації дії препаратів. Відома іммобілізація сульфаніламідних препаратів на стиромалі, метакрилатних полімерних матрицях, де фармакологічно активний сульфаніламід легко вивільняється з полімеру при застосуванні, в результаті кислотного гідролізу. Разом з тим спостерігається, що іммобілізовані сульфаніламіди, отримані на основі амінометильованого співполімеру стиролу з дивінілбензолом, незважаючи на стійкість до гідролізу, зберігають антибактеріальні властивості. З метою розширення прикладів ковалентної іммобілізації сульфаніламідів нами синтезовані 4-амінофенілсульфонаміди на гранульній і волокнистій формах співполімерів стиролу з дивінілбензолом через місткову групу SO2.Матеріали і методи. Як вихідну сировину використано макропористий гранульний співполімер стиролу з дивінілбензолом і сульфовані волокнисті форми прищепленого до поліпропіленової нитки співполімеру стиролу з дивінілбензолом. Сульфохлоруванням цих співполімерів отримано полімерні сульфохлориди, які використовували в реакції з 4-амінофенілсульфонамідом. Антибактеріальні властивості матеріалу досліджені за визначенням зон пригнічення росту тест-мікроорганізмів E.coli К-12 на поживному середовищі.Результати й обговорення. Будову синтезованих іммобілізованих 4-амінофенілсульфонамідів доведено методом ІЧ спектроскопії. Показано, що такі матеріали проявляють виражені антибактеріальні властивості щодо тест-культури мікроорганізмів E. coli К-12, незважаючи на їхню стійкість до гідролізу.Висновки. Зроблено припущення, що гідроліз матеріалів перебігає при специфічному ферментативному каталізі на поживному середовищі виділенням 4-амінофенілсульфонаміду
The CMS Micro-strip Gas Chamber Project: Development of a high resolution tracking detector for harsh radiation environments
Thirty-two large area Micro-Strip Gas Chambers were tested in a high intensity, 350~MeV pion beam at PSI to prove that we had reached a Milestone for the Compact Muon Solenoid (CMS) experiment. The particle rate was approximately 6 kHz/mm2, distributed over the whole active area of the detectors, and this rate was maintained for a total integrated time of 493 hours. All of the chambers were operated with signal-to-noise values at or above that corresponding to 98 % hit detection efficiency at CMS; the average S/N was 31. No indications of any gain instabilities or ageing effects were observed. In the official 3-week Milestone period, three strips from a total of 16384 were damaged, a result which is twenty times lower than the minimal requirement for CMS. The spark rate of the detectors was very low and decreased with time to an average of one spark per chamber per day. The cathode voltages of 24 of the chambers were increased over a one week period to investigate the behaviour of the detectors at higher gains; the maximum S/N value was 2.4 times that at the normal working point. No significant increase in spark rate or strip loss rate was detected and the chambers operated stably. The detector efficiencies and imaging capabilities were also investigated. The MSGC design features and the assembly and test methodologies that enabled us to achieve these results are reported
Search for invisible decays of sub-GeV dark photons in missing-energy events at the CERN SPS
We report on a direct search for sub-GeV dark photons (A') which might be
produced in the reaction e^- Z \to e^- Z A' via kinetic mixing with photons by
100 GeV electrons incident on an active target in the NA64 experiment at the
CERN SPS. The A's would decay invisibly into dark matter particles resulting in
events with large missing energy. No evidence for such decays was found with
2.75\cdot 10^{9} electrons on target. We set new limits on the \gamma-A' mixing
strength and exclude the invisible A' with a mass < 100 MeV as an explanation
of the muon g_\mu-2 anomaly.Comment: 6 pages, 3 figures; Typos corrected, references adde
Virucidal properties of new multifunctional fibrous N-halamine-immobilized styrene-divinylbenzene copolymers
Virucidal properties of N-chlorosulfonamides immobilized on fibrous styrene-divinylbenzene copolymers have been studied. Corresponding materials with different functional group structures and chlorine content have been synthesized on FIBAN polymer carriers in the form of staple fibers and non-woven fabrics. The study has been conducted in general accordance with EN 14476 standard on poliovirus type-1 and adenovirus type-5. It has been found that all tested samples exhibit pronounced virucidal activity: regardless of the carrier polymer form, sodium N-chlorosulfonamides inactivated both viruses in less than 30s, and N,N-dichlorosulfonamides— in 30–60 s. The main mechanism of action of these materials, obviously, consists in the emission of active chlorine from the functional group into the treated medium under the action of the amino
groups of virus fragments and cell culture. Considering the previously described antimicrobial and reparative properties of such materials, as well as their satisfactory physical and mechanical properties, the synthesized polymers are promising for the creation of medical devices with
increased resistance to microbial contamination, such as protective masks, filter elements, longacting wound dressings, and others
Production properties of K*(892) vector mesons and their spin alignment as measured in the NOMAD experiment
First measurements of K*(892) mesons production properties and their spin
alignment in nu_mu charged current (CC) and neutral current (NC) interactions
are presented. The analysis of the full data sample of the NOMAD experiment is
performed in different kinematic regions. For K*+ and K*- mesons produced in
nu_mu CC interactions and decaying into K0 pi+/- we have found the following
yields per event: (2.6 +/- 0.2 (stat.) +/- 0.2 (syst.))% and (1.6 +/- 0.1
(stat.) +/- 0.1 (syst.))% respectively, while for the K*+ and K*- mesons
produced in nu NC interactions the corresponding yields per event are: (2.5 +/-
0.3 (stat.) +/- 0.3 (syst.))% and (1.0 +/- 0.3 (stat.) +/- 0.2 (syst.))%. The
results obtained for the rho00 parameter, 0.40 +/- 0.06 (stat) +/- 0.03 (syst)
and 0.28 +/- 0.07 (stat) +/- 0.03 (syst) for K*+ and K*- produced in nu_mu CC
interactions, are compared to theoretical predictions tuned on LEP measurements
in e+e- annihilation at the Z0 pole. For K*+ mesons produced in nu NC
interactions the measured rho00 parameter is 0.66 +/- 0.10 (stat) +/- 0.05
(syst).Comment: 20 p
Search for Axionlike and Scalar Particles with the NA64 Experiment
We carried out a model-independent search for light scalar (s) and
pseudoscalar axionlike (a) particles that couple to two photons by using the
high-energy CERN SPS H4 electron beam. The new particles, if they exist, could
be produced through the Primakoff effect in interactions of hard bremsstrahlung
photons generated by 100 GeV electrons in the NA64 active dump with virtual
photons provided by the nuclei of the dump. The a(s) would penetrate the
downstream HCAL module, serving as shielding, and would be observed either
through their decay in the rest of the HCAL detector or
as events with large missing energy if the a(s) decays downstream of the HCAL.
This method allows for the probing the a(s) parameter space, including those
from generic axion models, inaccessible to previous experiments. No evidence of
such processes has been found from the analysis of the data corresponding to
electrons on target allowing to set new limits on the
-coupling strength for a(s) masses below 55 MeV.Comment: This publication is dedicated to the memory of our colleague Danila
Tlisov. 7 pages, 5 figures, revised version accepted for publication in Phys.
Rev. Let
Search for the exotic resonance in the NOMAD experiment
A search for exotic Theta baryon via Theta -> proton +Ks decay mode in the
NOMAD muon neutrino DIS data is reported. The special background generation
procedure was developed. The proton identification criteria are tuned to
maximize the sensitivity to the Theta signal as a function of xF which allows
to study the Theta production mechanism. We do not observe any evidence for the
Theta state in the NOMAD data. We provide an upper limit on Theta production
rate at 90% CL as 2.13 per 1000 of neutrino interactions.Comment: Accepted to European Physics Journal
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