ДОСЛІДЖЕННЯ ЕЛЕМЕНТНОГО СКЛАДУ ГРУШІ ЗВИЧАЙНОЇ ЛИСТЯ СОРТУ НОЯБРСЬКА

Introduction. Mineral elements are enzyme cofactors, constituents of vitamins, hormones, all body cells and tissues, they are essential for its normal metabolism: homeostasis support, progress of biochemical, enzymatic, plastic, hormonal, regulatory and metabolic processes, being a necessary and vital part of human diet. Their deficiency, excess or imbalance in the body may cause certain diseases, syndromes, disorders or pathological states. The object of the study were pear leaves of Noiabrska cultivar, collected in Ivano-Frankivsk region in August 2018. Pears of this cultivar are widely cultivated on the territory of Ukraine in private households or farms, especially in Western and Transdniester regions. The aim of the study – research on the qualitative composition and quantitative content of mineral elements in pear leaves of Noiabrska cultivar. Research Methods. The element composition of pear leaves of Noiabrska cultivar was studied using atomic-absorption spectrometry at the department of analytical chemistry of the State Scientific Institution “Institute for Single Crystals” of National Academy of Sciences of Ukraine. Results and Discussion. The obtained results of experimental research carried out show the presence of 19 mineral elements in pear leaves of Noiabrska cultivar. K (2185 mg/100 g), Ca (1140 mg/100 g), Mg (380 mg/100 g), P (85 mg/100 g), Si (76 mg/100 g) and Al (62 mg/100 g) were accumulated in the highest amount in the plant material, while Cu (0.23 mg/100 g), Ni (0.11 mg/100 g) and Mo (0.047 mg/100 g) – in the lowest. The content of heavy metals was within the limits of permissible concentration. Conclusions. 19 mineral elements were identified in pear leaves of Noiabrska cultivar, and their content was determined by the means of atomic-absorption spectrometry. The received experimental data will be used in further work at predictive modeling of pharmacological activity of the plant material studied, medicinal agents on its basis, as well as at standardization and development of quality control methods for the plant material.Вступление. Минеральные элементы являются кофакторами ферментов, составными частями витаминов, гормонов, всех клеток и тканей организма, они необходимы для его нормальной жизнедеятельности: поддержания гомеостаза, протекания биохимических, ферментативных, пластических, гормональных, регуляторных и обменных процессов, являются обязательной и незаменимой частью рациона питания. Их дефицит, избыток или дисбаланс в организме может вызвать определенные заболевания, синдромы, нарушения или патологические состояния. Объектом исследования были груши обыкновенной листья сорта Ноябрьская, заготовленные в Ивано-Франковской области в августе 2018 г. Груша обыкновенная данного сорта широко культивируется на территории Украины в частных и фермерских хозяйствах, особенно в западных регионах и Приднестровье. Цель исследования – изучить качественный состав и количественное содержание минеральных элементов в груши обыкновенной листьях сорта Ноябрьская. Методы исследования. Элементный состав определяли методом атомно-абсорбционной спектрометрии на базе отдела аналитической химии ГНУ НТК “Институт монокристаллов” НАН Украины. Результаты и обсуждение. Полученные результаты проведенных экспериментальных исследований свидетельствуют о наличии в груши обыкновенной листьях сорта Ноябрьская 19 минеральных элементов. В наибольшем количестве в сырье накапливались K (2185 мг/100 г), Ca (1140 мг/100 г), Mg (380 мг/100 г), P (85 мг/100 г), Si (76 мг/100 г) и Al (62 мг/100 г), в наименьшем – Cu (0,23 мг/100 г), Ni (0,11 мг/100 г) и Mo (0,047 мг/100 г). Содержание тяжелых металлов находилось в пределах допустимых концентраций. Выводы. Методом атомно-абсорбционной спектрометрии в груши обыкновенной листьях сорта Ноябрьская идентифицировано и определено количественное содержание 19 минеральных элементов. Полученные экспериментальные данные будут использованы в дальнейшей работе при прогнозировании фармакологической активности исследуемого сырья, лекарственных средств на его основе, а также с целью стандартизации и разработки методов контроля качества сырья.Вступ. Мінеральні елементи є кофакторами ферментів, складовими частинами вітамінів, гормонів, усіх клітин і тканин організму, вони необхідні для його нормальної життєдіяльності: підтримки гомеостазу, перебігу біохімічних, ферментативних, пластичних, гормональних, регуляторних та обмінних процесів, є обов’язковою і незамінною частиною раціону харчування. Їх дефіцит, надлишок чи дисбаланс в організмі може спричинити певні захворювання, синдроми, порушення або патологічні стани. Об’єктом дослідження були груші звичайної листя сорту Ноябрська, заготовлені в Івано-Франківській області в серпні 2018 р. Груша звичайна даного сорту широко культивується на території України у приватних і фермерських господарствах, особливо в західних регіонах та Придністров’ї. Мета дослідження – вивчити якісний склад та кількісний вміст мінеральних елементів у груші звичайної листі сорту Ноябрська. Методи дослідження. Елементний склад груші звичайної листя сорту Ноябрська изначали методом атомно-абсорбційної спектрометрії на базі відділу аналітичної хімії ДНУ НТК “Інститут монокристалів” НАН України. Результати й обговорення. Одержані результати проведених експериментальних досліджень свідчать про наявність у груші звичайної листі сорту Ноябрська 19 мінеральних елементів. У найбільшій кількості в сировині накопичувалися K (2185 мг/100 г), Ca (1140 мг/100 г), Mg (380 мг/100 г), P (85 мг/100 г), Si (76 мг/100 г) і Al (62 мг/100 г), у найменшій – Cu (0,23 мг/100 г), Ni (0,11 мг/100 г) та Mo (0,047 мг/100 г). Вміст важких металів перебував у межах допустимих концентрацій. Висновки. Методом атомно-абсорбційної спектрометрії у груші звичайної листі сорту Ноябрська ідентифіковано та визначено кількісний вміст 19 мінеральних елементів. Одержані експериментальні дані буде використано в подальшій роботі при прогнозуванні фармакологічної активності досліджуваної сировини, лікарських засобів на її основі, а також з метою стандартизації та розробки методів контролю якості сировини

Time-to-infection by Plasmodium falciparum is largely determined by random factors

BACKGROUND: The identification of protective immune responses to P. falciparum infection is an important goal for the development of a vaccine for malaria. This requires the identification of susceptible and resistant individuals, so that their immune responses may be studied. Time-to-infection studies are one method for identifying putative susceptible individuals (infected early) versus resistant individuals (infected late). However, the timing of infection is dependent on random factors, such as whether the subject was bitten by an infected mosquito, as well as individual factors, such as their level of immunity. It is important to understand how much of the observed variation in infection is simply due to chance. METHODS: We analyse previously published data from a treatment-time-to-infection study of 201 individuals aged 0.5 to 78 years living in Western Kenya. We use a mathematical modelling approach to investigate the role of immunity versus random factors in determining time-to-infection in this cohort. We extend this analysis using a modelling approach to understand what factors might increase or decrease the utility of these studies for identifying susceptible and resistant individuals. RESULTS: We find that, under most circumstances, the observed distribution of time-to-infection is consistent with this simply being a random process. We find that age, method for detection of infection (PCR versus microscopy), and underlying force of infection are all factors in determining whether time-to-infection is a useful correlate of immunity. CONCLUSIONS: Many epidemiological studies of P. falciparum infection assume that the observed variation in infection outcomes, such as time-to-infection or presence or absence of infection, is determined by host resistance or susceptibility. However, under most circumstances, this distribution appears largely due to the random timing of infection, particularly in children. More direct measurements, such as parasite growth rate, may be more useful than time-to-infection in segregating patients based on their level of immunity

The Dynamics of Naturally Acquired Immunity to Plasmodium falciparum Infection

Severe malaria occurs predominantly in young children and immunity to clinical disease is associated with cumulative exposure in holoendemic settings. The relative contribution of immunity against various stages of the parasite life cycle that results in controlling infection and limiting disease is not well understood. Here we analyse the dynamics of Plasmodium falciparum malaria infection after treatment in a cohort of 197 healthy study participants of different ages in order to model naturally acquired immunity. We find that both delayed time-to-infection and reductions in asymptomatic parasitaemias in older age groups can be explained by immunity that reduces the growth of blood stage as opposed to liver stage parasites. We found that this mechanism would require at least two components - a rapidly acting strain-specific component, as well as a slowly acquired cross-reactive or general immunity to all strains. Analysis and modelling of malaria infection dynamics and naturally acquired immunity with age provides important insights into what mechanisms of immune control may be harnessed by malaria vaccine strategists

Innate immunity induced by Plasmodium liver infection inhibits malaria reinfections

© 2015 American Society for Microbiology. The authors have paid a fee to allow immediate free access to this article.Following transmission through a mosquito bite to the mammalian host, Plasmodium parasites first invade and replicate inside hepatocytes before infecting erythrocytes and causing malaria. The mechanisms limiting Plasmodium reinfections in humans living in regions of malaria endemicity have mainly been explored by studying the resistance induced by the blood stage of infection. However, epidemiologic studies have suggested that in high-transmission areas, preerythrocytic stages also activate host resistance to reinfection. This, along with the recent discovery that liver infections trigger a specific and effective type I interferon (IFN) response, prompted us to hypothesize that this pre-erythrocyte-stage-induced resistance is linked to liver innate immunity. Here, we combined experimental approaches and mathematical modeling to recapitulate field studies and understand the molecular basis behind such resistance. We present a newly established mouse reinfection model and demonstrate that rodent malaria liver-stage infection inhibits reinfection. This protection relies on the activation of innate immunity and involves the type I IFN response and the antimicrobial cytokine gamma IFN (IFN-γ). Importantly, mathematical simulations indicate that the predictions based on our experimental murine reinfection model fit available epidemiological data. Overall, our study revealed that liver-stage-induced innate immunity may contribute to the preerythrocytic resistance observed in humans in regions of malaria hyperendemicity.This work was supported by Fundação para a Ciência e Tecnologia (FCT, Portugal) grants PTDC-SAU-MIC-117060-2010 (to Miguel Prudêncio) and EXCL/IMI-MIC/0056/2012 (to M.M.M.). P.L. was supported by Fondation pour la Recherche Médicale and FCT (fellowship SFRH/BPD/41547/2007). P.M. was supported by FCT (fellowship SFRH/BD/71098/2010). Miguel Prudêncio and M.P.D. are supported by an Australian Research Council Discovery Grant (DP120100064). M.P.D. is an NHMRC Senior Research Fellow.info:eu-repo/semantics/publishedVersio

Beam coupling in hybrid photorefractive inorganic-cholesteric liquid crystal cells: impact of optical rotation

We develop a theoretical model to describe two-beam energy exchange in a hybrid photorefractive inorganic-cholesteric cell. A cholesteric layer is placed between two inorganic substrates. One of the substrates is photorefractive (Ce:SBN). Weak and strong light beams are incident on the hybrid cell. The interfering light beams induce a periodic space-charge field in the photorefractive window. This penetrates into the cholesteric liquid crystal (LC), inducing a diffraction grating written on the LC director. In the theory, the flexoelectric mechanism for electric field-director coupling is more important than the LC static dielectric anisotropy coupling. The LC optics is described in the Bragg regime. Each beam induces two circular polarized waves propagating in the cholesteric cell with different velocities. The model thus includes optical rotation in the cholesteric LC. The incident light beam wavelength can fall above, below, or inside the cholesteric gap. The theory calculates the energy gain of the weak beam, as a result of its interaction with the pump beam within the diffraction grating. Theoretical results for exponential gain coefficients are compared with experimental results for hybrid cells filled with cholesteric mixture BL038/CB15 at different concentrations of chiral agent CB15. Reconciliation between theory and experiment requires the inclusion of a phenomenological multiplier in the magnitude of the director grating. This multiplier is cubic in the space-charge field, and we provide a justification of the q-dependence of the multiplier. Within this paradigm, we are able to fit theory to experimental data for cholesteric mixtures with different spectral position of cholesteric gap relative to the wavelength of incident beams, subject to the use of some fitting parameters

The temporal dynamics and infectiousness of subpatent Plasmodium falciparum infections in relation to parasite density

Malaria infections occurring below the limit of detection of standard diagnostics are common in all endemic settings. However, key questions remain surrounding their contribution to sustaining transmission and whether they need to be detected and targeted to achieve malaria elimination. In this study we analyse a range of malaria datasets to quantify the density, detectability, course of infection and infectiousness of subpatent infections. Asymptomatically infected individuals have lower parasite densities on average in low transmission settings compared to individuals in higher transmission settings. In cohort studies, subpatent infections are found to be predictive of future periods of patent infection and in membrane feeding studies, individuals infected with subpatent asexual parasite densities are found to be approximately a third as infectious to mosquitoes as individuals with patent (asexual parasite) infection. These results indicate that subpatent infections contribute to the infectious reservoir, may be long lasting, and require more sensitive diagnostics to detect them in lower transmission settings