Розробка та валідація ВЕРХ/УФ-методики визначення секнідазолу

Secnidazole is one of antiprotozoal medicines from the group of 5-nitroimidazoles, the method of HPLC with different types of detection is widely used for secnidazole determination.Aim. To develop the HPLC/UV-procedure of secnidazole quantification with application of the system of a “MiLiChrome® A-02” HPLC-analyzer and carry out the step-by-step validation of the procedure developed. Results and discussion. The specificity of the chromatographic conditions proposed was confirmed in relation to other medicines of the group of 5-nitroimidazoles (metronidazole, tinidazole, ornidazole and nimorazole). The retention time for secnidazole was 8.16 min. 0.01 M solution of hydrochloric acid was proposed for preparation of the reference and model solutions in developing the HPLC/UV-procedure of secnidazole quantification. To prove the possibility of application of the procedure proposed in further analysis its validation was carried out in the variants of the method of the calibration curve and the method of standard. Such validation parameters as in-process stability, linearity/calibration model, accuracy and precision (repeatability) were estimated using model solutions.      Experimental part. The HPLC/UV analyses were performed using a MiLiChrome® A-02 high pressure liquid chromatograph (EcoNova, Russia). Eluent A (0.2 M LiClO4 – 0.005 M HClO4) and Eluent B (acetonitrile) were used as the mobile phase components. The HPLC microcolumn with the size of Ø2 × 75 mm and the ProntoSIL 120-5-C18 AQ reversed phase, 5 μm (BISCHOFF Analysentechnik und -geräte GmbH, Germany) was used as an analytical column. The analysis was performed at 40 °С and the flow rate of 100 μl/min. The mobile phase was run in the gradient elution mode, namely from 5 % to 100 % of Eluent B for 40 min, then 100 % of Eluent B for 3 min. Detection was performed at 277 nm.                                                                      Conclusions. A new procedure of the secnidazole quantitative determination by the method of HPLC/UV has been developed. Its validation has been carried out, and acceptability for its application has been shown.Секнидазол является одним из антипротозойных препаратов из группы 5-нитроимидазолов, для определения которого широко используется метод ВЭЖХ с различными типами детекции.Цель. Разработать ВЭЖХ/УФ-методику количественного определения секнидазола с использованием системы ВЭЖХ-анализатора «MiLiChrome® A-02» и провести поэтапную валидацию разработанной методики.        Результаты и их обсуждение. Специфичность предлагаемых хроматографических условий подтверждена в отношении других препаратов из группы 5-нитроимидазолов (метронидазола, тинидазола, орнидазола и ниморазола). Время удерживания для секнидазола составляет 8,16 мин; 0,01 М раствор хлористоводородной кислоты был предложен для приготовления раствора сравнения и модельных растворов при разработке ВЭЖХ/УФ-методики количественного определения секнидазола. Для доказательства возможности применения предлагаемой методики в дальнейшем анализе валидация была проведена в вариантах метода калибровочного графика и метода стандарта. Такие валидационные параметры, как стабильность, линейность/калибровочная модель, правильность и прецизионность были оценены с помощью модельных растворов.                              Экспериментальная часть. ВЭЖХ/УФ-анализ проводили с использованием жидкостного хроматографа высокого давления MiLiChrome® A-02 (EcoNova, Россия). В качестве компонентов подвижной фазы использовали элюент А (0,2 М LiClO4 – 0,005 М HClO4) и элюент В (ацетонитрил). В качестве аналитической колонки использовали ВЭЖХ-микроколонку размером Ø2 × 75 мм с обращенной фазой ProntoSIL 120-5-C18 AQ, 5 мкм (BISCHOFF Analysentechnik und -geräte GmbH, Германия). Анализ проводили при 40 °С и скорости потока 100 мкл/мин. Мобильная фаза подавалась в режиме градиентного элюирования – от 5 % до 100 % элюента В в течение 40 мин, затем 100 % элюента В в течение 3 мин. Детектирование проводили при 277 нм.                                                                                                  Выводы. Разработана новая методика количественного определения секнидазола методом ВЭЖХ/УФ. Проведена ее валидация и показана приемлемость для применения.Секнідазол є одним з антипротозойних препаратів з групи 5-нітроімідазолів, для визначення якого широко використовується метод ВЕРХ з різними типами детекції.Мета. Розробити ВЕРХ/УФ-методику кількісного визначення секнідазолу з використанням системи ВЕРХ-аналізатора «MiLiChrome® A-02» і провести поетапну валідацію розробленої методики.Результати та їх обговорення. Специфічність запропонованих хроматографічних умов підтверджено відносно інших препаратів з групи 5-нітроімідазолів (метронідазолу, тінідазолу, орнідазолу і німоразолу). Час утримування для секнідазолу становить 8,16 хв; 0,01 М розчин хлористоводневої кислоти було запропоновано для приготування розчину порівняння і модельних розчинів при розробці ВЕРХ/УФ-методики кількісного визначення секнідазолу. Для доказу можливості застосування пропонованої методики в подальшому аналізі була проведена її валідація у варіантах методу калібрувального графіка і методу стандарту. Такі валідаційні параметри, як стабільність, лінійність/калібрувальна модель, правильність і прецизійність були оцінені за допомогою модельних розчинів.Експериментальна частина. ВЕРХ/УФ-аналіз проводили з використанням рідинного хроматографа високого тиску MiLiChrome® A-02 (EcoNova, Росія). Як компоненти рухомої фази використовували елюент А (0,2 М LiClO4 – 0,005 М HClO4) і елюент В (ацетонітрил). Як аналітичну колонку використовували ВЕРХ-мікроколонку розміром Ø2 × 75 мм з оберненою фазою ProntoSIL 120-5-C18 AQ, 5 мкм (BISCHOFF Analysentechnik und -geräte GmbH, Німеччина). Аналіз проводили при 40 °С і швидкості потоку 100 мкл/хв. Мобільна фаза подавалася в режимі градієнтного елюювання – від 5 % до 100 % елюенту В впродовж 40 хв, потім 100 % елюенту В впродовж 3 хв. Детектування проводили при 277 нм.Висновки. Розроблено нову методику кількісного визначення секнідазолу методом ВЕРХ/УФ. Проведена її валідація і показана прийнятність для застосування

The minimal compound-complex sentence hierarchy

This article deals with the problem of the study of the subsystem of such type of the Multiple Compound-Complex Sentence as a minimal compound-complex sentence. The authors analyze the formal structure of the multiple compoundcomplex sentences and try to build up the structural models hierarchy of Minimal Compound-Complex SentenceyesBelgorod State Universit

Improving educational process quality in the lessons of natural and mathematical cycle by means of stem-training

Today, the educational process is focused on the development of personal characteristics that meet the requirements of a modern educated person. In this regard, the task of educational institutions is to adopt the educational process to today’s realities. To achieve this goal, STEM education is implemente

The collection of potato varieties as a reserve of source material for breeding for high yield, earliness, and resistance to diseases and pests

Background. Information is provided about the results obtained by screening the VIR collection of improved potato varieties for main commercial traits: earliness, high yield, high starch content, and resistance to late blight (Phytophthora infestans (Mont.) de Bary), viruses, and pests, such as cyst nematode (Globodera rostochiensis Woll. (Ro1)), and Colorado beetle (Leptinotarsa decemlineata Say).Materials and methods. Potato accessions representing domestic and foreign varieties from the VIR collection served as the material for this research. The screening was performed according to the techniques developed at the Potato Genetic Resources Department of VIR.Results and conclusion. Potato varieties with valuable commercial traits were identified as breeding sources promising for earliness: ‘Bashkirskiy’ (k-25338), ‘Charoit’ (k-25221), ‘Colleen’ (k-25224), ‘Lagun’ (k-25294), etc.; for high yield: ‘Ametist’ (k-25336), ‘Banba’ (k-25222), ‘Bastion’ (k-25198), ‘Nur-Alem’ (k-25253), ‘Senim’ (k-25306), etc.; for high starch content: ‘Charaўnik’ (k-25139), ‘Darnitsa’ (k-25179), ‘Lad’ (k-25180), ‘Maksimum’ (k-25136), etc.; for resistance to late blight: local variety (Georgia) (k-25298, k-25326), ‘Sunkar’ (k-25258), ‘Udovitskiy’ (k-25260), ‘Vektor’ (k-25200), ‘Zvezdochka’ (k-25209); for resistance to viruses: ‘Azart’ (k-25196), Gala (k-25270), ‘Nadezhda’ (k-25213), Utro (k-25219), ‘Volat’ (k-25263), etc. Varieties combining resistance to gold potato cyst nematode with other valuable commercial traits were selected. Varieties with relative resistance to Colorado potato beetle were isolated under favorable conditions for the pest’s development. As a result of the research, new source material was identified, with a potential to improve major commercial traits of potato: earliness, high yield, high starch content, resistance to late blight, viruses, and pests (cyst nematode and Colorado beetle)

Radiobiological experiments with plant seeds aboard the biosatellite Cosmos 1887

The effects of spaceflight factors on the seeds of Arabidopsis thaliana and Crepis capillaris were studied. The seeds were located inside the satellite in an open space, protected with aluminum foil and also exposed without the foil cover. When the seeds were in open space without any protection, their viability was found to be suppressed; the survival rate and fertility of plants grown from these seeds were also diminished. An increase in the frequency of chromosome aberrations (CA) and in the number of multiple injuries was registered in this case. Experiments with the aluminum foil shielding showed a decrease in the suppression of the seeds' viability, but mutational changes were found to be even more increased, while the survival rate and fertility of the plants decreased. An increase in the thickness of shielding resulted in a decrease in the effects up to the level of the control, except for the effects connected with CA and fertility of the plants. Analysis of the results shows that these impairments can be ascribed to the action of single heavy charged particles (HCP). The seeds can thus be regarded as an integral biological 'dosimeter' which allows estimation of the total effects of radiation, ecological and biological factors

Experimental studies of energy characteristics of mixer with deformable camera

Currently the development of new machine designs and methods of their engineering calculation is one of the most priority areas of construction industry. It allows one to carry out research at the stage of theoretical calculations in order to predict the expected result. One of the promising constructive solutions for economic profitability increase of mixing equipment is the use of deformable working chamber

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Male sterility in potato is little studied since traditional breeding is based  on the vegetative reproduction of highly heterozygous tetraploid varieties. The rapid development of hybrid diploid breeding contributes to growing interest in studying the male sterility of this important crop. In this work, a set of 6 cytoplasmic markers was employed to describe cytoplasmic genetic diversity of 185 potato cultivars bred in Russia and FSU countries. Three cytoplasm types were identified, T (40.0 %), D (50.8 %) and W/γ (8.7 %), which according to literature  are associated with male sterility. With a single exception (0.5 %), cytoplasm types characteristic of male fertile forms (A, P) were not found in the subset  of 185 cultivars. A comparison of these results with previously published data suggested expanding the subset  to up to 277 cultivars, all developed in Russia or FSU countries;  however,  the resulting  differentiation into three cytoplasm  types (T, D and W/γ) was nearly the same. Fertility phenotyping helped identify both  male-sterile and male-fertile genotypes within the three groups  of varieties with T-, D- and W/γ-type cytoplasm. Fifteen genotypes differing in cytoplasm  type and male sterility/fertility traits were selected for direct sequencing of 8 mtDNA loci. Fragments of the  nad2, nad7, cox2, atp6 and  CcmFc genes  were identical  in all 15 selected genotypes. The polymorphism, detected in the rps3, atp9 and CcmFc loci, was not associated with male sterility. Two SNPs in the nad1/atp6 and nad2 loci differentiated 7 genotypes with W/γ-type cytoplasm into five genotypes with tetrad sterility, and two with fertile pollen. The results of an NGS analysis confirmed  the association of these  SNPs with tetrad sterility in a larger set of 28 genotypes of different origin, all with W/γ-type cytoplasm.  A heteroplasmy state  was observed both in male-sterile and in male-fertile genotypes

MOLECULAR SCREENING OF POTATO VARIETIES BRED IN THE NORTHWESTERN ZONE OF THE RUSSIAN FEDERАTION

Increasing the resistance of varieties to diseases and pests is a priority in potato breeding. Many potato varieties created in the Leningrad Scientific Research Institute of Agriculture “Belogorka” are multi-species hybrids possessing complex resistance to the most spread pathogens in combination with a high plasticity, which determined their zoning in many regions of the Russian Federation. Potato varieties and hybrids created in different periods of time in this institute and in the Ltd Breeding company “LiGa” were included in marker-assisted selection with 22 markers of 14 R genes conferring extreme resistance to viruses PVY and PVX, resistance to cyst nematodes Globodera pallida (patotypes Pa2, Pa3) and G. rostochiensis (pathotype Ro1) and resistance to late blight. The data of molecular screening were compared with the results of the State Test of Varieties for Disease Resistance, as well as with other published sources. Markers of sterile and fertile cytoplasm types were also used in the study. Based on the results of molecular screening, varieties and hybrids with different combinations of markers of R genes conferring resistance to the most harmful pathogens (Rysto, Ry-fsto, Rx1, Rx2, Gro1-4, H1, Gpa2, R1, R3a, Rpi-blb1, Rpi-sto1) were detected. Among them, genotypes with sterile D-, T-, W/gamma cytoplasmic types were selected. Analysis of their pollen fertility, crossability and pedigree data showed that breeders succeed in obtaining fertile forms with the D- and T-types of cytoplasm carrying genetic material of Mexican polyploid species Solanum stoloniferum and S. demissum. The information about the presence of markers of R genes and about cytoplasm types of hybrids and varieties will allow an effective implementation of further breeding programs for resistance to a complex of pathogens, including pyramiding of R genes. The data of molecular screening made it possible to specify the pedigrees of several varieties and hybrids that have been created over several decades

Study of the role of metalloproteinases and their inhibitors in the formation of posttoxic fibrosis and cirrhosis and the use of oxidized dextran in the experiment.

The purpose of the work is to evaluate the significance of metalloproteinases (MMPs) and their inhibitors in the formation of liver fibrosis and cirrhosis in the outcome of chronic hepatosis of mixed toxic etiology and the use of OD in the experiment.Цель работы − оценка значения металлопротеиназ (ММР) и их ингибиторов в формировании фиброза и цирроза печени в исходе хронического гепатоза смешанной токсической этиологии и применение окисленного декстрана (ОД) в эксперименте

First experience of using Brentuximab vedotin and modified program NHL-BFM-90 in the front-line treatment of patient with anaplastic large-cell lymphoma: a case report and a review of literature

Nodal anaplastic ALK-negative large cell lymphoma (nALCL, ALK-) is a Т-cell lymphoma that is characterized by aggressive clinical course and low sensitivity to СНОР (cyclophosphamide, doxorubicin, vincristine, prednisolone) and other chemotherapy regimen. In the article we present a literature review and describe our clinical case of nALCL, ALK-. For the first time a combination of Brentuximab vedotin with modified program NHL-BFM-90 was used as a first-line therapy. As a result of immunochemotherapy a complete antineoplastic effect was obtained. For consolidation of this effect high-dose chemotherapy with following autologous blood stem cell transplantation was performed. The chosen treatment tactics allowed to achieve a complete remission in a medium risk group patient