67 research outputs found
Use of internet resources in the process of the Olympiad
Increased student interest in studying subjects is possible through active involvement in participation in competitions and contests. On the example of the developed and implemented Olympiad site, the realized opportunities and the mechanism of holding such an event, as well as the results obtained during the implementation of a single resource, are consideredПовышение заинтересованности студентов в изучении предметов, возможно через активное вовлечение к участию в олимпиадах и конкурсах. На примере разработанного и внедренного сайта олимпиады рассматриваются реализованные возможности и механизм проведения подобного мероприятия, а также результаты, полученные в ходе внедрения единого ресурс
Technology for Creation and Detailed Analysis of Polymer Composites with Uniform Distribution of Quantum Dots and Liquid Crystals
One of the most actual tasks in biotechnology is the creation of a new generation of nanobiosensors with improved brightness, photo stability, and sensitivity. Compositions of polymers and colloidal quantum dots (QDs) are the most promising base to develop such sensors. This work presents the technology for creation and detailed analysis of nanostructured composite films based on polypropylene matrices with uniformly distributed CdSe/ZnS quantum dots and liquid crystals. Methods of optical microscopy, scanning probe microscopy and confocal fluorescen tmicrospectroscopy were used. The presence of liquid crystals in the composite allows additional control of QDs fluorescence. The methodology proposed is applicable not only to polypropylene, but also to other porous polymers. The results of this work indicate the possibility of creating high-quality polymer/QDs composite materials and open the way to the development of nanomaterials (nanosensors) with optical properties sensitive to various environmental parameters (electric field, photo irradiation, mechanical action, etc.).
Keywords: quantum dot-polymer composites, nanoporous polypropylene, fluorescenc
Сomparative analysis of wild and cultivated Lathyrus L. spp. according to their primary and secondary metabolite contents
Species of the genus Lathyrus L. are known as forage and medicinal plants, widely used in traditional medicine and homeopathy. The content of protein, essential amino acids and carotene in their green biomass is higher than in other annual leguminous plants traditionally cultivated in Russia. Until now, the requirements for the crop’s quality were reduced to a high content of protein and dry matter in seeds and herbage. In-depth biochemical analysis of accessions from the collection of plant genetic resources will significantly improve selection of source materials for breeding. Such tasks can be solved using gas chromatography with mass spectrometry in plant diversity studies. In view of the above, our goal was to analyze organic acids, free amino acids and secondary metabolites in green biomass of Lathyrus to facilitate comprehensive assessment of its forage and pharmacological value. We analyzed 32 accessions of Lathyrus sativus L., L. tuberosus L., L. sylvestris L., L. vernus (L.) Bernh., L. latifolius L. and L. linifolius (Reichard) Bassler from the collection of the Vavilov Institute (VIR). The studied Lathyrus accessions had significant interspecific and intraspecific variability both in the composition (presence) and number of the identified compounds. The analysis of plants across different years confirmed that biochemical parameters depended on weather conditions. The colder and drier conditions of 2012 contributed to the accumulation of organic acids (mean: 890 mg/100 g), free amino acids (mean: 201.59 mg/100 g), and secondary metabolites (mean: 84.14 mg/100 g). The range of variability for organic acids ranged from 140 to 2140, for free amino acids from 11.8 to 610, and for secondary metabolites from 4.4 to 224.6 mg/100 g. Grass pea accessions with high organic acid, free amino acid and secondary metabolite contents were identified: k-900 (Colombia) for organic acids (2140, 610 and 178 mg/100 g); k-51 (Georgia) and k-959 (Afghanistan) for free amino acids (401.29 and 540.63 mg/100 g); k-893 (Eritrea) for secondary metabolites (199.39 mg/100 g), etc. They can serve as source material for the development of cultivars for different uses (forage and medicinal)
USING OF SULFONATED CYANINE DYES IN PLASMON LABELS FOR BIOIMAGING BY RAMAN SPECTROSCOPY
This work was supported by Russian Science Foundation, grant № 22-73-10052. The authors would like to thank the Resource Centres of SPbU: "Optical and Laser Materials Research", "Chemical Analysis and Material Research" and "Interdisciplinary Center for Nanotechnology"
Comparative analysis of wild and cultivated Lathyrus L. species to assess their content of sugars, polyols, free fatty acids, and phytosterols
Under climate change, the need for crops resistant to abiotic and biotic stresses increases. Lathyrus spp. Are characterized by a high nutritional value of their green biomass. The grass pea is one of the most resistant to drought, aterlogging, cold, salinity, diseases and pests among cultivated legumes, and it is grown at minimal cost. The development of new Lathyrus cultivars with an improved composition of nutrients will make it possible to produce high-quality animal feed in areas with extremely unstable weather conditions. With this in view, the patterns of variability in the parameters of the carbohydrate complex (sugars, their lactone and methyl forms), polyols (including phenol-containing alcohols), phytosterols, free fatty acids (FFA) and acylglycerols were studied in the green biomass of 32 accessions representing Lathyrus sativus L., L. tuberosus L., L. sylvestris L., L. vernus (L.) Bernh., L. latifolius L. and L. linifolius (Reichard) Bassler. from the VIR collection, reproduced in Leningrad oblast under contrasting conditions of 2012 and 2013. The content of identified compounds varied depending on the genotype, species, and weather. High temperatures and high precipitation in 2013 contributed to the accumulation of monosaccharides, and the colder and drier conditions of 2012 to an increase in oligosaccharides, most polyols, and FFA. The cultivated species (L. sativus) was distinguished by its high sugar content, and the wild species as follows: L. latifolius by FFA; L. linifolius by ononitol, myo-inositol, and glycerol 3-phosphate; L. vernus by MAG and methylpentofuranoside. The resulting data showed that the Lathyrus accessions studied are promising for breeding stress-resistant cultivars of high nutritional quality
Neoglycolipids Micelle-like Structures as a Basis for Drug Delivery Systems
Targeted drug delivery is one of the most promising tasks of nanomedicine, as this is a real way to increase the effectiveness of therapeutic effects against many diseases. In this regard, the development of new inexpensive highly effective stimulating and non-immunogenic drug delivery systems (DDS) is of great importance. In this work new molecular candidates were proposed and studied for the creation of such systems based on the use of new compounds, neoglycolipids. It is shown that these compounds are capable of self-association in aqueous solutions and can serve as potential carriers of drug compounds with targeted delivery determined by their terminal groups (in particular, glycans). The processes of their associates formation and features of their structure are investigated. The results show that these selforganizing nanoscale systems can be used as a basis for developing new drug delivery systems.
Keywords: neoglycolipids, micelle-like structures, small-angle X-ray scattering, molecular dynamics simulatio
Human Mesenchymal Stem Cells Overexpressing Interleukin 2 Can Suppress Proliferation of Neuroblastoma Cells in Co-Culture and Activate Mononuclear Cells In Vitro
High-dose recombinant interleukin 2 (IL2) therapy has been shown to be successful in renal cell carcinoma and metastatic melanoma. However, systemic administration of high doses of IL2 can be toxic, causing capillary leakage syndrome and stimulating pro-tumor immune response. One of the strategies to reduce the systemic toxicity of IL2 is the use of mesenchymal stem cells (MSCs) as a vehicle for the targeted delivery of IL2. Human adipose tissue-derived MSCs were transduced with lentivirus encoding IL2 (hADSCs-IL2) or blue fluorescent protein (BFP) (hADSCs-BFP). The proliferation, immunophenotype, cytokine profile and ultrastructure of hADSCs-IL2 and hADSCs-BFP were determined. The effect of hADSCs on activation of peripheral blood mononuclear cells (PBMCs) and proliferation and viability of SH-SY5Y neuroblastoma cells after co-culture with native hADSCs, hADSCs-BFP or hADSCs-IL2 on plastic and Matrigel was evaluated. Ultrastructure and cytokine production by hADSCs-IL2 showed modest changes in comparison with hADSCs and hADSCs-BFP. Conditioned medium from hADSC-IL2 affected tumor cell proliferation, increasing the proliferation of SH-SY5Y cells and also increasing the number of late-activated T-cells, natural killer (NK) cells, NKT-cells and activated T-killers. Conversely, hADSC-IL2 co-culture led to a decrease in SH-SY5Y proliferation on plastic and Matrigel. These data show that hADSCs-IL2 can reduce SH-SY5Y proliferation and activate PBMCs in vitro. However, IL2-mediated therapeutic effects of hADSCs could be offset by the increased expression of pro-oncogenes, as well as the natural ability of hADSCs to promote the progression of some tumors
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