327 research outputs found
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Bigger Than Grain: Soviet-American Agricultural Exchange, 1918-1928
This dissertation examines the history of agricultural exchange between the United States and Soviet Russia from 1918 to 1928. It shows that Soviet and American agricultural specialists and policymakers sought solutions to the looming global farm crisis of the 1920s through visits, the organization of reconstruction projects, and seed exchange. In doing so, this work advances three arguments. First, the development of post-World War I agriculture, including concepts of large-scale farming, industrialization of agricultural, and rationalization of food production, should be understood within an international context. As the First World war reshaped patterns of agricultural production and showed the inextricable link between food and political stability, experts and policymakers from many countries began to search for solutions to the farm problem not only through national policies but also abroad. As this dissertation shows, this search would take different shapes and forms: from the use of international food aid programs to help domestic food production to the usage of another country’s space to conduct large-scale farming experiments. These experiences in agricultural exchange allowed its participants to acquire new knowledge, technologies, and expertise.Second, by examining post-WWI patterns of agricultural exchange, this dissertation reconsiders the relationship between the United States and the Soviet Union with regard to the flow of technology and expertise. Rather than considering a one-directional movement of American technology and expertise to Soviet Russia and perceiving the latter as a passive recipient, this work portrays an active multi-directional exchange. It shows that both countries perceived each other as research laboratories that were capable of giving solutions to farm problems in their respective countries. Moreover, both American and Soviet agricultural experts believed that this exchange would benefit the reconstruction of international agriculture.Finally, this dissertation expands the definition of “agricultural exchange.” Scholars have demonstrated that, historically, agricultural exchange, including the movement of plants, seeds, and agricultural knowledge and expertise, is not a new event. The flow of people and animal species brought new plant varieties and agricultural technologies to new places, thus, changing existing environments, economic and social structures. While these transfers knew no borders, since the late nineteenth and early twentieth centuries, they had become more institutionalized and regulated by the international community of scientists and policymakers. During this period, many national governments introduced new laws and regulations that controlled the import and export of agricultural commodities. What is often left out in this historiography is the political nature of agricultural exchange. This dissertation shows that participants of agricultural exchange used their experience and expertise that they cultivated through visits and travel to achieve more powerful positions with local and central state institutions. Yet, this experience came at a price. By the late 1920s, with the shifting political climate in the Soviet Union, the participation in agricultural exchange became one of the tools for the ostracization of these experts from powerful positions
Steatosis-induced proteins adducts with lipid peroxidation products and nuclear electrophilic stress in hepatocytes
AbstractAccumulating evidence suggests that fatty livers are particularly more susceptible to several pathological conditions, including hepatic inflammation, cirrhosis and liver cancer. However the exact mechanism of such susceptibility is still largely obscure. The current study aimed to elucidate the effect of hepatocytes lipid accumulation on the nuclear electrophilic stress. Accumulation of intracellular lipids was significantly increased in HepG2 cells incubated with fatty acid (FA) complex (1mM, 2:1 oleic and palmitic acids). In FA-treated cells, lipid droplets were localized around the nucleus and seemed to induce mechanical force, leading to the disruption of the nucleus morphology. Level of reactive oxygen species (ROS) was significantly increased in FA-loaded cells and was further augmented by treatment with moderate stressor (CoCl2). Increased ROS resulted in formation of reactive carbonyls (aldehydes and ketones, derived from lipid peroxidation) with a strong perinuclear accumulation. Mass-spectroscopy analysis indicated that lipid accumulation per-se can results in modification of nuclear protein by reactive lipid peroxidation products (oxoLPP). 235 Modified proteins involved in transcription regulation, splicing, protein synthesis and degradation, DNA repair and lipid metabolism were identified uniquely in FA-treated cells. These findings suggest that steatosis can affect nuclear redox state, and induce modifications of nuclear proteins by reactive oxoLPP accumulated in the perinuclear space upon FA-treatment
Computational solutions in redox lipidomics – Current strategies and future perspectives
Abstract The high chemical diversity of lipids allows them to perform multiple biological functions ranging from serving as structural building blocks of biological membranes to regulation of metabolism and signal transduction. In addition to the native lipidome, lipid species derived from enzymatic and non-enzymatic modifications (the epilipidome) make the overall picture even more complex, as their functions are still largely unknown. Oxidized lipids represent the fraction of epilipidome which has attracted high scientific attention due to their apparent involvement in the onset and development of numerous human disorders. Development of high-throughput analytical methods such as liquid chromatography coupled on-line to mass spectrometry provides the possibility to address epilipidome diversity in complex biological samples. However, the main bottleneck of redox lipidomics, the branch of lipidomics dealing with the characterization of oxidized lipids, remains the lack of optimal computational tools for robust, accurate and specific identification of already discovered and yet unknown modified lipids. Here we discuss the main principles of high-throughput identification of lipids and their modified forms and review the main software tools currently available in redox lipidomics. Different levels of confidence for software assisted identification of redox lipidome are defined and necessary steps toward optimal computational solutions are proposed
Портфолио научно-исследовательской деятельности студента
Проанализированы преимущества использования технологии портфолио в мониторинге научно-исследовательской деятельности студентов, при этом особо отмечены возможности развития рефлексивного мышления студентов и формирования общей культуры научной деятельности. Предложена модель портфолио научно-исследовательской деятельности
Redox lipidomics and adductomics - advanced analytical strategies to study oxidized lipids and lipid-protein adducts
No abstract available.publishe
A Single Dose of Atorvastatin Applied Acutely after Spinal Cord Injury Suppresses Inflammation, Apoptosis, and Promotes Axon Outgrowth, Which Might Be Essential for Favorable Functional Outcome.
The aim of our study was to limit the inflammatory response after a spinal cord injury (SCI) using Atorvastatin (ATR), a potent inhibitor of cholesterol biosynthesis. Adult Wistar rats were divided into five experimental groups: one control group, two Th9 compression (40 g/15 min) groups, and two Th9 compression + ATR (5 mg/kg, i.p.) groups. The animals survived one day and six weeks. ATR applied in a single dose immediately post-SCI strongly reduced IL-1β release at 4 and 24 h and considerably reduced the activation of resident cells at one day post-injury. Acute ATR treatment effectively prevented the excessive infiltration of destructive M1 macrophages cranially, at the lesion site, and caudally (by 66%, 62%, and 52%, respectively) one day post-injury, whereas the infiltration of beneficial M2 macrophages was less affected (by 27%, 41%, and 16%). In addition, at the same time point, ATR visibly decreased caspase-3 cleavage in neurons, astrocytes, and oligodendrocytes. Six weeks post-SCI, ATR increased the expression of neurofilaments in the dorsolateral columns and Gap43-positive fibers in the lateral columns around the epicenter, and from day 30 to 42, significantly improved the motor activity of the hindlimbs. We suggest that early modulation of the inflammatory response via effects on the M1/M2 macrophages and the inhibition of caspase-3 expression could be crucial for the functional outcome
Theranostic materials for MRI and targeted delivery based on functionalized magnetite nanoparticles
In the last decades, the synthesis of magnetic nanoparticles, in particular magnetite nanoparticles (MNPs), has received increased attention due to their wide range of applications in biomedicine and technology. MNPs can be effectively used for diagnostics and treatment of various diseases. Size, shape, charge and surface chemistry of NPs are fundamental characteristics that determine substantially their properties. Moreover, these characteristics have a big role in the processes of pharmacokinetics and pharmacodynamics. Magnetite nanoparticles are nontoxic, biocompatible and degradable material.
Considering current demographic trends in the world and the nature of the dynamics of morbidity, we can expect that even if the average level of cancer incidence will occur more than 15 million new cases of malignant neoplasms in the population each year. It is obviously that the increase of cancer incidence will be occur substantially due to prostate cancer in men, tumors of the colon and rectum in men and women. Thus the problem of creating universal drug (theranostic materials) for early diagnosis and treatment of malignancy becomes more and more actual.
The opportunity of application of magnetite nanoparticles in MRI and drug delivery is highly dependent on their sizes and magnetic characteristics. In this work we attempted to create materials based on MNPs for prostate cancer therapy and diagnostics. We carried out synthesis of magnetite nanoparticles with different morphology (cubes, rod-like, star-like and flower-like) and with average size from 10 to 50 nm. Obtained nanoparticles were synthesized by thermal decomposition of iron-containing precursors in high-boiling organic solvents, as well as the aging method in aqueous medium. All nanoparticles were characterized by different physicochemical methods such as: transmission electron microscopy, X-ray diffraction, thermogravimetric analysis, ICP - MS. Also magnetic measurements of samples were carried out. For transfer of MNPs from the organic into the aqueous medium and to prevent aggregation MNPs were functionalized and coated with biocompatible copolymers based on polyethyleneglycol and pluronic.
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Analysis of oxidised and glycated aminophospholipids: complete structural characterisation by C30 liquid chromatography-high resolution tandem mass spectrometry
The aminophospholipids (APL), phosphatidylethanolamine (PE) and phosphatidylserine (PS) are widely present in cell membranes and lipoproteins. Glucose and reactive oxygen species (ROS), such as the hydroxyl radical (•OH), can react with APL leading to an array of oxidised, glycated and glycoxidised derivatives. Modified APL have been implicated in inflammatory diseases and diabetes, and were identified as signalling molecules regulating cell death. However, the biological relevance of these molecules has not been completely established, since they are present in very low amounts, and new sensitive methodologies are needed to detect them in biological systems. Few studies have focused on the characterisation of APL modifications using liquid chromatography-tandem mass spectrometry (LC-MS/MS), mainly using C5 or C18 reversed phase (RP) columns. In the present study, we propose a new analytical approach for the characterisation of complex mixtures of oxidised, glycated and glycoxidised PE and PS. This LC approach was based on a reversed-phase C30 column combined with high-resolution MS, and higher energy C-trap dissociation (HCD) MS/MS. C30 RP-LC separated short and long fatty acyl oxidation products, along with glycoxidised APL bearing oxidative modifications on the glucose moiety and the fatty acyl chains. Functional isomers (e.g. hydroxy-hydroperoxy-APL and tri-hydroxy-APL) and positional isomers (e.g. 9-hydroxy-APL and 13-hydroxy-APL) were also discriminated by the method. HCD fragmentation patterns allowed unequivocal structural characterisation of the modified APL, and are translatable into targeted MS/MS fingerprinting of the modified derivatives in biological samples.publishe
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