Influence of multicomponent contamination on the content of photosynthetic pigments in the leaves of woody plants commonly planted for greening of cities

Woody plants, as an important element of optimization of the urban environment, respond negatively to the ever-increasing technogenic pressure in cities. Therefore, it is necessary to assess their vital status, the most sensitive indicator of which being the content of plastid pigments. In this article we analyze the effects of multicomponent contamination on quantitative fluctuation of the level of photosynthetic pigments in the leaves of woody plants and identify sensitive species for the purpose of phytoindication in order to assess the state the environment is currently in. For the purposes of our research we chose the most widespread tree species in the city of Dnipro (Steppe zone of Ukraine), growing in the area of intensive industrial pollution and high levels of emissions by vehicles. We determined the content of photosynthetic pigments (chlorophylls a and b, a + b, carotenoids) in the leaves of woody plants during different months of the growing season (June, July, August) and afterwards this data was used to compare the given parameters against the values taken from trees in the control area. The sum of chlorophyll levels a + b for the majority of plants was decreasing compared to the control. A more significant decrease in the content given by the sum of the a and b chlorophyll levels is observed in the assimilation organs of Aesculus hippocastanum L., Pinus pallasiana (D. Don) and Picea abies (L.) H. The most significant changes in the content of pigments in the leaves of plants under study were detected at the end of the growing season (in August). The content of green pigments in the leaves of Robinia pseudoacacia L., Platanus orientalis L. remains virtually unchanged. Under the influence of multicomponent contamination, the amount of pigments in the case of chlorophyll a in the majority of woody plant species decreases more rapidly compared to the control than in the case of chlorophyll b. The most noticeable drop in the content of chlorophyll a occurs in the leaves of Betula pendula Roth, Ae. hippocastanum, P. pallasiana, Acer platanoides L. and Tilia cordata Mill. The needles of P. abies and Picea pungens Engelm. 'Glauca’ on the contrary suffer from a significant reduction in the concentration of chlorophyll b. The species most resistant to multicomponent contamination in terms of changes in the content of chlorophyll in the leaf blade are R. pseudoacacia, P. orientalis. The concentration of carotenoids in the leaves of plants such as B. pendula, Ae. hippocastanum, A. platanoides, T. cordata, P. abies is lower than that of species growing in the relatively clean zone. The concentration of pigments in Populus alba L., P. pungens 'Glauca’ was higher during all of the months elapsed since the beginning of our study, whereas Ulmus laevis Pall., P. orientalis and R. pseudoacacia – had their concentrations reach an all time high in the second half of the growing season. Therefore, the peculiarities of quantitative fluctuation of photosynthetic pigments in plants, which are characterized by the variable resistance ability against the effects of technogenic multicomponent contamination, have been identified

Values and preferences for hepatitis C self-testing among people who inject drugs in Kyrgyzstan

Background: The prevalence of hepatitis C virus (HCV) among people who inject drugs (PWID) continues to be a major public-health burden in this highly stigmatised population. To halt transmission of HCV, rapid HCV self-testing kits represent an innovative approach that could enable PWID to know their HCV status and seek treatment. As no HCV test has yet been licenced for self-administration, it is crucial to obtain knowledge around the factors that may deter or foster delivery of HCV self-testing among PWID in resource-constrained countries. Methods: A qualitative study to assess values and preferences relating to HCV self-testing was conducted in mid-2020 among PWID in the Bishkek and Chui regions of Kyrgyzstan. Forty-seven PWID participated in 15 individual interviews, two group interviews (n = 12) and one participatory action-research session (n = 20). Responses were analysed using a thematic analysis approach with 4 predefined themes: awareness of HCV and current HCV testing experiences, and acceptability and service delivery preferences for HCV self-testing. Informants’ insights were analysed using a thematic analysis approach. This research received local ethics approval. Results: Awareness of HCV is low and currently PWID prefer community-based HCV testing due to stigma encountered in other healthcare settings. HCV self-testing would be accepted and appreciated by PWID. Acceptability may increase if HCV self-testing: was delivered in pharmacies or by harm reduction associations; was free of charge; was oral rather than blood-based; included instructions with images and clear information on the test’s accuracy; and was distributed alongside pre- and post-testing counselling with linkage to confirmatory testing support. Conclusions: HCV self-testing could increase awareness of and more frequent testing for HCV infection among PWID in Kyrgyzstan. It is recommended that peer-driven associations are involved in the delivery of any HCV self-testing. Furthermore, efforts should be maximised to end discrimination against PWID at the healthcare institutions responsible for confirmatory HCV testing and treatment provision. © 2021, The Author(s)

ДЕНДРОФЛОРА БАЛКИ ШИРОКА (ОСТРІВ ХОРТИЦЯ)

Ravine forests are samples of intrazonal vegetation where numerous representatives of the fauna live, as well as plants of forest, steppe, meadow and other types of phytocoenosis, many of which are rare and endemic species. Сonsequently, the study of the taxonomic structure of their flora and the impact of recreational activities on the biodiversity of these natural forests is relevant. The route method based on the biogeocenotical principle for the defining of the species composition of the dendroflora represents the research technique. The research provides data on the species composition of the dendroflora of ravine Shyroka ravine, Khortytsya (recreational area of tourists and residents of Zaporizhzhia), where 54 species of woody plants belonging to 43 genera and 26 families grow. As a result, the study reviled that the Rosaceae Adans family is characterized by the highest species diversity. In the composition of the dendroflora of the birch forest, 48.1 % are native species, 51.9 % are introduced. The largest share of the introduced species belongs to the species of North American origin (11 species, or 39.3 % of the total number of alien species). Amorpha fruticosa, Robinia pseudoacacia, Morus alba and Celtis occidentalis represent the introductants. The main forest-forming aboriginal species of the plantation are Acer platanoides, Quercusrobur, Ulmusscabra, A. tataricum. The study demonstrates the pedigree composition of the overstorey and undergrowth on the territory of various morphological parts of the ravine. Ravine forest has a significant resource potential, including honey and vitamin plants. Species with high invasive capacity (Acer negundo, Amorpha fruticosa, Robinia pseudoacacia) and those recognized as invasive (Parthenocissus quinquifolia) occur in the plantation. Сonsequently, the directions for future research is a detailed study of the natural renewal of native and introduced tree species, which are part of the plantation of the ravine forest, as well as further monitoring of the distribution of invasive species on the territory of the ravine.Байрачні ліси Запорізької обл. відносять до байраків порожистої частини Дніпра. Вони мають важливе кліматичне та ґрунтозахисне значення, у них трапляються представники лісових, степових, лугових фітоценозів, часто – рідкісні й ендемічні види, а також місцева фауна. Такі заліснені балки характеризуються високою атракторною здатністю для рекреантів, діяльність яких призводить до трансформації рослинності байрачно-лісових фітоценозів. З огляду на це актуальною є інформація про стан їх дендрофлори для створення банку даних та оперативного моніторингу. Наведено дані про видовий склад дендрофлори балки Широка, розташованої на о. Хортиця (зона рекреаційної діяльності туристів та мешканців м. Запоріжжя), де зареєстровано 54 види деревних рослин, що належать до 43 родів і 26 родин. Встановлено, що найбільшим видовим насиченням характеризується родина Rosaceae Adans. У складі дендрофлори байрачного лісу аборигенні види становлять 48,1 %, інтродуковані – 51,9 %. Найбільша частка участі серед інтродукованих видів належить породам північноамериканського походження (11 видів, або 39,3 % від усієї кількості інтродуцентів). Інтродуценти представлені здебільшого Amorpha fruticosa, Robinia pseudoacacia, Morus alba та Celtis occidentalis. Основними лісотвірними аборигенними породами насадження є Acer platanoides, Quercus robur, Ulmus scabra, A. tataricum. З'ясовано породний склад верхніх ярусів деревостану та підліску, що зростають на території різних морфологічних частин балки. Байрачний ліс має значний ресурсний потенціал, включаючи медоносні та вітамінні рослини. У складі насадження виявлено види з високою інвазійною здатністю (Acer negundo, Amorpha fruticosa, Robinia pseudoacacia) та той, що визнано інвазійним у списках близьких до України територій (Parthenocіssus quinquifolia)

ХРОМАТОГРАФИЧЕСКОЕ И ХРОМАТО-МАСС-СПЕКТРОМЕТРИЧЕСКОЕ ОПРЕДЕЛЕНИЕ ПРОТИВОТУБЕРКУЛЕЗНЫХ ПРЕПАРАТОВ ОСНОВНОГО РЯДА В ПЛАЗМЕ КРОВИ

In the current study the possibility of the simultaneous determination of anti-tuberculosis (anti-TB) drugs (isoniazid, pyrazinamide, ethambutol and rifampicin) using the reversed-phase HPLC (RP-HPLC) and ion-pair chromatography was investigated. A selective and highly sensitive liquid chromatography/tandem mass spectrometry method for the simultaneous determination of four anti-TB drugs (isoniazid, pyrazinamide, ethambutol and rifampicin) in the human plasma was developed. The detection was carried out using the multiple reaction-monitoring (MRM) modes with positive polarity. The fragmentation conditions for each drug were optimized, and the conditions for the blood plasma preparation for HPLC/MS analysis, including the protein precipitation with ACN with a ratio of 3:1 (by volume), were chosen. The matrix effects on the separation and ionization of anti-TB drugs were estimated by the post-extraction additives method. It was shown that the 10-fold dilution of plasma extracts was sufficient to decrease the influence of the sample matrix. The stability of anti-TB drugs during the analysis (in autosampler at 1 and 12 hours) and at storage conditions (3 cycles of freeze-thaw) was studied. The method for increasing the stability of rifampicin using ascorbic acid (1 mg/ml) as antioxidant was provided. The LOD with UV detection were 2 – 20 µg/ml, in SIM-mode – 2 – 15 ng/ml and in MRM-mode – 0.5 – 10 ng/ml respectively. The possibility of the determination of four anti-TB drugs in real plasma samples of patients with tuberculosis undergoing drug therapy in optimized conditions HPLC/MC was shown.Key words: anti-tuberculosis drugs, RP HPLC, LC/MS/MS, matrix effect(Russian)DOI: http://dx.doi.org/10.15826/analitika.2016.20.2.007 E.A. Bessonova, L.A. Kartsova, S.A. Soloveva Saint-Petersburg State University, 7/9 Universitetskaya nab., St. Petersburg, 199034, Russian FederationВ работе выявлены возможности одновременного определения четырех противотуберкулезных препаратов (ПТП)  (этамбутол, пиразинамид, изониазид, рифампицин) методами обращённо-фазовой ВЭЖХ (ОФ ВЭЖХ) и ион-парной хроматографии.  Предложен вариант одновременного определения этих ПТП в плазме крови человека методом ОФ ВЭЖХ с тандемным масс-спектрометрическим детектированием с электроспрей ионизацией. Детектирование осуществляли в режиме положительной ионизации путём мониторинга множественных реакций (MRM). Оптимизированы условия фрагментации для каждого лекарственного вещества. Найдены условия подготовки плазмы крови к ВЭЖХ/МС анализу, включающие осаждение белков плазмы крови ацетонитрилом. Значения степеней извлечения ПТП составили 85-90 %. Проведена оценка влияния матрицы пробы на разделение и ионизацию ПТП методом пост-экстракционной добавки. Показано, что разбавление экстракта плазмы крови в 10 раз достаточно для требуемого снижения матричного эффекта.  Изучена стабильность ПТП в процессе анализа (автосамплер 1 и 12 ч.) и в условиях хранения (3 цикла заморозка-разморозка). Предложен способ увеличения стабильности рифампицина с добавлением в качестве антиоксиданта аскорбиновой кислоты (1 мг/мл). Пределы обнаружения с УФ детектированием составили от 2 до 20 мкг/мл, с МС детектированием в SIM–режиме от 2 до 15 нг/мл и в MRM–режиме от 0.5 до 10 нг/мл. В оптимизированных условиях показана возможность обнаружения и количественного определения всех четырех ПТП в плазме крови больного туберкулезом с проводимой лекарственной терапией. Ключевые слова: противотуберкулёзные препараты, ОФ ВЭЖХ, масс-спектрометрическое детектирование, матричный эффект, стабильность рифампицинаDOI: http://dx.doi.org/10.15826/analitika.2016.20.2.00

Chromatographic and liquid chromatography-tandem-mass spectrometry determination of first-line anti-tuberculosis drugs in human plasma

В работе выявлены возможности одновременного определения четырех противотуберкулезных препаратов (ПТП) ( этамбутол, пиразинамид, изониазид, рифампицин ) методами обращённо-фазовой ВЭЖХ (ОФ ВЭЖХ) и ион-парной хроматографии. Предложен вариант одновременного определения этих ПТП в плазме крови человека методом ОФ ВЭЖХ с тандемным масс-спектрометрическим детектированием с электроспрей ионизацией. Детектирование осуществляли в режиме положительной ионизации путём мониторинга множественных реакций (MRM). Оптимизированы условия фрагментации для каждого лекарственного вещества. Найдены условия подготовки плазмы крови к ВЭЖХ/МС анализу, включающие осаждение белков плазмы крови ацетонитрилом. Значения степеней извлечения ПТП составили 85-90 %. Проведена оценка влияния матрицы пробы на разделение и ионизацию ПТП методом пост-экстракционной добавки. Показано, что разбавление экстракта плазмы крови в 10 раз достаточно для требуемого снижения матричного эффекта. Изучена стабильность ПТП в процессе анализа (автосамплер 1 и 12 ч.) и в условиях хранения (3 цикла заморозка-разморозка). Предложен способ увеличения стабильности рифампицина с добавлением в качестве антиоксиданта аскорбиновой кислоты (1 мг/мл). Пределы обнаружения с УФ детектированием составили от 2 до 20 мкг/мл, с МС детектированием в SIM-режиме от 2 до 15 нг/мл и в MRM-режиме от 0.5 до 10 нг/мл. В оптимизированных условиях показана возможность обнаружения и количественного определения всех четырех ПТП в плазме крови больного туберкулезом с проводимой лекарственной терапией.In the current study the possibility of the simultaneous determination of anti-tuberculosis (anti-TB) drugs (isoniazid, pyrazinamide, ethambutol and rifampicin) using the reversed-phase HPLC (RP-HPLC) and ion-pair chromatography was investigated. A selective and highly sensitive liquid chromatography/tandem mass spectrometry method for the simultaneous determination of four anti-TB drugs (isoniazid, pyrazinamide, ethambutol and rifampicin) in the human plasma was developed. The detection was carried out using the multiple reaction-monitoring (MRM) modes with positive polarity. The fragmentation conditions for each drug were optimized, and the conditions for the blood plasma preparation for HPLC/MS analysis, including the protein precipitation with ACN with a ratio of 3:1 (by volume), were chosen. The matrix effects on the separation and ionization of anti-TB drugs were estimated by the post-extraction additives method. It was shown that the 10-fold dilution of plasma extracts was sufficient to decrease the influence of the sample matrix. The stability of anti-TB drugs during the analysis (in autosampler at 1 and 12 hours) and at storage conditions (3 cycles of freeze-thaw) was studied. The method for increasing the stability of rifampicin using ascorbic acid (1 mg/ml) as antioxidant was provided. The LOD with UV detection were 2 - 20 µg/ml, in SIM-mode - 2 - 15 ng/ml and in MRM-mode - 0.5 - 10 ng/ml respectively. The possibility of the determination of four anti-TB drugs in real plasma samples of patients with tuberculosis undergoing drug therapy in optimized conditions HPLC/MC was shown

Differential diagnostics of poisoning by various alcohols

This article provides some characteristic for medical staff about poisoning by rare alcohols, their features in the clinic and their mechanism, a comparative characteristic by poisoning with well-known alcohol – ethanol.В данной статье приводится характеристика для медицинских сотрудников об отравлении редкими спиртами, их особенностях в клинике и механизме, сравнительная характеристика с отравлением известным спиртом – этанолом

Polymer Magnetooptical Composites for the IR Range

The magnetotransmission of composite structures based on doped La0.67Ba0.33MnO3 man-ganite has been studied. For the pressed La0.67Ba0.33MnO3+CsJ composite, the effect was about –2.6% over the entire range, which is close to the effects in films, but lower than in bulk manganites.Работа выполнена в рамках государственного задания МИНОБРНАУКИ России (тема «Спин», № 122021000036-3)

CREATION OF A HIGH–PERFORMANCE HARDWARE AND SOFTWARE COMPLEX FOR SOLVING PROBLEMS OF MOLECULAR DYNAMIC MODELING

Analysis of existing software solutions and technologies in the field of molecular dynamic modeling, determination of their advantages and disadvantages, creation of new approaches and algorithms to improve the efficiency of molecular dynamic modeling. Conducting research on commercialization