Enhancing Antibiotic Activity Using Nanomaterial-Antibiotic Conjugates

We demonstrate that streptomycin conjugated on silica nanoparticles (SNP-Str) can be used to effectively target streptomycin-resistant Escherichia coli (E. coli) bacteria by lowering the minimum inhibitory concentration (MIC) of streptomycin up to 2 log folds. Silica nanoparticles were synthesized with an average diameter of 80, 50 and 30 nm, respectively. Streptomycin was then covalently conjugated to SNP using efficient photocoupling chemistry. The MIC for free streptomycin sulfate was recorded as a high 2.0 mg/mL for an engineered Strr mutant E. coli ORN 208. Conjugating the streptomycin to SNP resulted in the decrease in MIC to 161 μg/mL, 63 μg/mL, and 19 μg/mL for SNP of 80, 50 and 30 nm, respectively. In this poster, the synthesis, characterization, and evaluation of SNP-Str will be presented and discussed

Фармакологічна безпечність комбінованого засобу для корекції плацентарної дисфункції у вагітних

Topicality. Along with the pronounced pharmacological effectiveness, high requirements for the safety are applied to new medicines. To obtain the necessary information regarding the safety of a potential drug and predict the risk of further side effects, a preclinical study of possible toxic effects, primarily acute toxicity, is performed.Aim. To study the acute toxicity of a new pharmaceutical composition for the correction of placental dysfunction in pregnant women.Materials and methods. The study object was the pharmaceutical composition in the form of solid gelatinous capsules containing active pharmaceutical ingredients from basic therapeutic group of drugs used for fetoplacental dysfunction in pregnant women. The acute toxicity was determined according to the methodological guidelines “Preclinical studies of drugs” edited by A. Stefanov, in outbreed female rats weighing 200-250 g in compliance with the “European Convention for the Protection of Vertebrate Animals used for Experimental and other Scientific Purposes” (Strasburg, 1985).Results and discussion. The study of the pharmaceutical safety has been performed by the acute toxicity criterion under the condition of short-term influence of a new pharmaceutical composition combining the required pharmaceutical ingredients in well-balanced doses affecting different chains of pathogenesis of placental dysfunction. Under the condition of the acute experiment a new combined composition (intraperitoneal introduction in the dose of 5000 mg/kg of the body weight) does not cause changes in the rat’s organism. It has been determined that this pharmaceutical composition belongs to practically nontoxic substances – Toxicity Class V according to the generally accepted classification system.Conclusions. The data for the preclinical safety assessment of a new combined composition for the correction of placental dysfunction in pregnant women have been obtained.Актуальность. К новым лекарственным препаратам наряду с выраженной фармакологической эффективностью предъявляются высокие требования в отношении их безопасности. Для получения необходимой информации о безопасности потенциального средства и прогнозировании риска возникновения в дальнейшем побочного действия проводится доклиническое изучение возможных токсических эффектов, в первую очередь острой токсичности.Цель. Целью данной работы является исследование острой токсичности комбинированного препарата для коррекции плацентарной дисфункции у беременных.Материалы и методы. Объектом исследования была фармацевтическая композиция в форме твердых желатиновых капсул, которая содержит активные ингредиенты из групп базовой терапии фетоплацентарной дисфункции у беременных. Исследование ее острой токсичности проводилось согласно методическим рекомендациям «Доклинические исследования лекарственных средств» под редакцией Стефанова А. В. на беспородных крысах-самках массой тела 200-250 г с соблюдением основных положений Конвенции Совета Европы об охране позвоночных животных, используемых в экспериментах и в других научных целях.Результаты и их обсуждение. Проведено исследование фармацевтической безопасности согласно критерия острой токсичности в условиях кратковременного влияния нового комбинированного препарата, который содержит в одной лекарственной форме необходимые активные фармацевтические ингредиенты в сбалансированном количестве, влияющие на несколько звеньев патогенеза плацентарной дисфункции. В условиях острого эксперимента новый комбинированный препарат (внутрижелудочное введение в дозе 5000 мг/кг массы тела) не вызывает изменений в организме крыс. Установлено, что фармацевтическая композиция согласно общепринятой класификации токсичности относится к классу практически нетоксичных веществ – V классу токсичности.Выводы. Получены данные в отношении доклинической оценки безопасности нового комбинированного препарата для коррекции плацентарной дисфункции у беременных.Актуальність. До нових лікарських препаратів поряд із вираженою фармакологічною ефективністю висувають підвищені вимоги щодо їх безпечності. Для отримання необхідної інформації про безпечність потенційного засобу та прогнозування ризику виникнення негативної дії в подальшому проводять доклінічне вивчення можливих токсичних ефектів, насамперед гострої токсичності.Мета. Метою нашої роботи є дослідження гострої токсичності комбінованого засобу для корекції плацентарної дисфункції у вагітних. Матеріали та методи. Об’єкт дослідження становила фармацевтична композиція у формі твердих желатинових капсул, що містить активні інгредієнти з груп базової терапії фетоплацентарної дисфункції у вагітних. Визначення її гострої токсичності здійснювали згідно з методичними рекомендаціями «Доклінічні дослідження лікарських засобів» за редакцією Стефанова О. В. на безпородних щурах-самицях масою тіла 200-250 г із дотриманням основних положень Конвенції Ради Європи про охорону хребетних тварин, які використовуються в експериментах та в інших наукових цілях.Результати та їх обговорення. Проведено дослідження фармацевтичної безпечності за критерієм гострої токсичності в умовах короткочасного впливу нового комбінованого засобу, що об’єднує в одній лікарській формі необхідні активні фармацевтичні інгредієнти в збалансованій кількості, які можуть впливати на декілька ланок патогенезу плацентарної дисфункції. За умов гострого експерименту новий комбінований засіб (внутрішньошлункове введення в дозі 5000 мг/кг маси тіла) не викликає змін в організмі щурів. З’ясовано, що фармацевтична композиція за загальноприйнятою класифікацією токсичності належить до практично нетоксичних речовин – до V класу токсичності.Висновки. Отримано дані щодо доклінічної оцінки безпеки нового комбінованого засобу для корекції плацентарної дисфункції у вагітних

THE PECULIARITIES OF DISTRACTION REGENERATE BONE IN EXPERIMENT WHILE CHRONIC STIMULATION OF BIOLOGICALLY ACTIVE POINTS

In experiment the forming and remodeling of distraction regenerate in rabbits Shinshila while conducting transosseous elements through the acupuncture points were studied. One of the rabbit's forearm was stretched by Hizarov's method for 10 mm. Multidetector CT gave the results of mineral density of the bone distraction regenerate. To the 10th day of fixation of bone fragments by the external fixation device the distraction regenerate with a clear zonal structure formed. To the 20th day of fixation in the middle zone there were clear signs of the formation of the medullary canal, that proves the decrease of mineral density to negative values. The prolonged stimulation of acupuncture points by introduced transosseous elements leads to formation of the structure and properties of bone regenerate, which are close by the characteristics to the parameters of the intact bone

Evidence for Narrow N*(1685) Resonance in Quasifree Compton Scattering on the Neutron

The first study of quasi-free Compton scattering on the neutron in the energy range of $E_{\gamma}=0.75 - 1.5$ GeV is presented. The data reveals a narrow peak at $W\sim 1.685$ GeV. This result, being considered in conjunction with the recent evidence for a narrow structure at $W\sim 1.68$GeV in the $\eta$ photoproduction on the neutron, suggests the existence of a new nucleon resonance with unusual properties: the mass $M\sim 1.685$GeV, the narrow width $\Gamma \leq 30$MeV, and the much stronger photoexcitation on the neutron than on the proton.Comment: Replaced with the version published in Phys. Rev.

Presence of inductivity in (CoFeZr)x(PZT)1-x nanocomposite produced by ion beam sputtering

This paper presents the investigations of the electrical properties of the (CoFeZr)x(PZT)1x nanocomposite with the metallic phase content x = 43:8 at.%, which was produced by ion beam sputtering. Such preparation took place under an argon atmosphere with low oxygen content with its partial pressure PO2 = 2 mPa. The measurements were performed using alternating current within the frequency range of 50 Hz – 0.1 MHz for measuring temperatures ranging from 238 K to 328 K. The (CoFeZr)43:8(PZT)56:2 nanocomposite sample subjected to a 15 min annealing process in air at the temperature Ta = 423 K demonstrates a phase angle of 90 in the frequency range 50 Hz – 0.1 MHz. It corresponds to the capacitive type of conduction. In the frequency range 10 – 100 kHz sharp minima in selected conductivity vs. frequency characteristics occur, which corresponds to a current resonance phenomenon in RLC circuits. In case of a sample annealed at Ta = 498 K the inductive type of conduction with +90 occurs in a high frequency area. At the frequency fr characterized by the phase angle = 0 , the capacity value reaches its local minimum. It indicates a voltage resonance phenomenon in conventional RLC circuits. The +90 crossing in the frequency dependence of phase angle corresponds to the current resonance phenomenon, which is represented by a strong local minimum in the conductivity vs. frequency characteristics

Magnetoconductivity of quantum wires with elastic and inelastic scattering

We use a Boltzmann equation to determine the magnetoconductivity of quantum wires. The presence of a confining potential in addition to the magnetic field removes the degeneracy of the Landau levels and allows one to associate a group velocity with each single-particle state. The distribution function describing the occupation of these single-particle states satisfies a Boltzmann equation, which may be solved exactly in the case of impurity scattering. In the case where the electrons scatter against both phonons and impurities we solve numerically - and in certain limits analytically - the integral equation for the distribution function, and determine the conductivity as a function of temperature and magnetic field. The magnetoconductivity exhibits a maximum at a temperature, which depends on the relative strength of the impurity and electron-phonon scattering, and shows oscillations when the Fermi energy or the magnetic field is varied.Comment: 21 pages (revtex 3.0), 5 postscript figures available upon request at [email protected] or [email protected]

Dielectric properties of nanocomposite (Cu)x(SiO2)(100-x) produced by ion-beam sputtering

It has been established that in the nanocomposite Cux(SiO2)(100 x) with the metallic phase content x = 27.27 at.% the following phenomena occur: hopping conductivity, additional polarity and coilless-like inductance. Coilless-like inductance phenomenon consists in the occurrence of positive values of phase shift in the high frequency area. Activation energy of the dielectric relaxation time for copper nanoparticles of unoxidized surface is of approx. 0.0003 eV, whereas surface oxidation causes a potential barrier occurrence and activation energy increase up to approx. 0.3360 eV. Comparative analysis of results obtained for the Cux(SiO2)(100 x) material and the measurements results obtained for the nanocomposites (FeCoZr)x(Al2O3)(100 x), (FeCoZr)x(CaF2)(100 x) and (FeCoZr)x(PZT)(100 x), which containing nanoparticles of ferromagnetic alloy, has been performed. It has shown that the type of magnetic properties of metallic phase, which is ferromagnetic ones for FeCoZr and diamagnetic ones for Cu, does not affect capacitive and inductive phenomena of the nanocomposites. The phenomena are related only to the nanogranular structure of the materials and the hopping mechanism of the charge transport between the metallic phase nanoparticles

PLAGUE INFECTION SIMULATING IN CASE OF INOCULATION WITH AVIRULENT YERSINIA PESTIS STRAINS

Biological method of investigation is specified for the laboratory diagnostics of plague. Mastering of this method by the trainees within the frames of further vocational education is associated with the use of avirulent Yersinia pestis strains and vaccine Y. pestis strain EV line, which while providing safety does not allow for typical pathomorphological pattern on biomodels, as well as for isolation of microorganisms from internal organs. Objective of the study is to select avirulent Yersinia pestis strains and to conduct comparative analysis of the simulation techniques for plague on biomodels. Materials and methods. Utilized were Y. pestis strains. Virulence was evaluated both, in vitro (polymerase chain reaction) and in vivo (LD50 for white mice). Results and conclusions. Set forward have been avirulent Y. pestis strains, prospective in terms of mastering biological method of laboratory diagnostics of plague, and means of their application for simulating plague in biomodels. The designed approach allows for exercising biological methods of plague investigation to the fullest extent, enhancing biological safety of practical studies and reducing the time line for isolation and accumulation of pure bacterial culture