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Bryan Holder opublikował 1 rok, 8 miesięcy temu
Moreover, we determined that the preclusion of Lewis acid-base complexation between the Ni catalyst and the base, due to steric factors, is important for avoiding catalyst inhibition.The use of DNA-encoded libraries has emerged as a powerful hit generation technology. Combining the power of combinatorial chemistry to enumerate large compound collections with the efficiency of affinity selection in pools, the methodology makes it possible to interrogate vast chemical space against biological targets of pharmaceutical relevance. Thus, the chemical transformations employed for the synthesis of encoded libraries play a crucial role in the identification of diverse and drug-like starting points. Currently established transformations have mostly been limited to water-compatible reactions to accommodate the growing oligonucleotide tag. Herein, we describe the development of a practical catch-and-release methodology utilizing a cationic, amphiphilic PEG-based polymer to perform chemical transformations on immobilized DNA conjugates under anhydrous conditions. We demonstrate the usefulness of our APTAC (amphiphilic polymer-facilitated transformations under anhydrous conditions) approach by performing several challenging transformations on DNA-conjugated small molecules in pure organic solvents the addition of a carbanion equivalent to a DNA-conjugated ketone in tetrahydrofuran, the synthesis of saturated heterocycles using the tin (Sn) amine protocol (SnAP) in dichloromethane, and the dual-catalytic (Ir/Ni) metallaphotoredox decarboxylative cross-coupling of carboxylic acids to DNA-conjugated aryl halides in DMSO. In addition, we demonstrate the feasibility of the latter in multititer-plate format.Cancerous microvesicles (MVs), which are heterogeneous membrane-bound nanovesicles shed from the surfaces of cancer cells into the extracellular environment, have been widely recognized as promising „biofingerprints” for various cancers. High-performance identification of cancerous MVs plays a vital role in the early diagnosis of cancer, yet it is still technically challenging. Herein, we report a gold nanoparticle (AuNP)-decorated, dual-aptamer modified reduced graphene oxide (RGO) field-effect transistor (AAP-GFET) nanosensor for the label-free, specific, and sensitive quantification of HepG2 cell-derived MVs (HepG2-MVs). After GFET chips were fabricated, AuNPs were then decorated on the RGO surface. For specific capture and detection of HepG2-MVs, both sulfhydrylated HepG2 cell specific TLS11a aptamer (AptTLS11a) and epithelial cell adhesion molecule aptamer (AptEpCAM) were immobilized on the AuNP surface through an Au-S bond. This developed nanosensor delivered a broad linear dynamic range from 6 × 105 to 6 × 109 particles/mL and achieved a high sensitivity of 84 particles/μL for HepG2-MVs detection. Moreover, this AAP-GFET platform was able to distinguish HepG2-MVs from other liver cancer-related serum proteins (such as AFP and CEA) and MVs derived from human normal cells and other cancer cells of lung, pancreas, and prostate, suggesting its excellent method specificity. Compared with those modified with a single type of aptamer alone (AptTLS11a or AptEpCAM), such an AAP-GFET nanosensor showed greatly enhanced signals, suggesting that the dual-aptamer-based bio-nano interface was uniquely designed and could realize more sensitive quantification of HepG2-MVs. Using this platform to detect HepG2-MVs in clinical blood samples, we found that there were significant differences between healthy controls and hepatocellular carcinoma (HCC) patients, indicating its great potential in early HCC diagnosis.As synthetic biology and metabolic engineering tools improve, it is feasible to construct more complex microbial synthesis systems that may be limited by the machinery and resources available in an individual cell. Coculture fermentation is a promising strategy for overcoming these constraints by distributing objectives between subpopulations, but the primary method for controlling the composition of the coculture of production systems has been limited to control of the inoculum composition. We have developed a quorum sensing (QS)-based growth-regulation circuit that provides an additional parameter for regulating the composition of a coculture over the course of the fermentation. Implementation of this tool in a naringenin-producing coculture resulted in a 60% titer increase over a system that was optimized by varying inoculation ratios only. We additionally demonstrated that the growth control circuit can be implemented in combination with a communication module that couples transcription in one subpopulation to the cell-density of the other population for coordination of behavior, resulting in an additional 60% improvement in naringenin titer.Ganoderma mushrooms have been widely used as functional food in China, Japan, and Korea. Ganoderma triterpenoids are deemed to be the main functional constituents. The structures of Ganoderma triterpenoids are complex but quite similar, which makes their analyses markedly limited. In this study, we developed a general 2D NMR method to differentiate Ganoderma triterpenoids, which classifies them into six types (A-F). Then, by the NMR-based isolation of A-F type triterpenoids from the fruiting bodies of G. resinaceum, four new compounds (1-4) and eight known compounds (5-12) were obtained. Moreover, combined with spiking experiments in 1D and 2D NMR spectra, compounds 5, 7, and 8, which belong to triterpenoids of A and B types, were identified. At the end, to achieve a more extensive application for this NMR method, a qNMR method for the absolute quantification of 5, 7, and 8 in the gross triterpenoids from G. resinaceum was set up. The results showed that this NMR method is reliable for the NMR-guided isolation and quantification of triterpenoids in G. resinaceum.The biobank is a structure established with the goal of long-term responsible storage of biological samples and the associated data for their further use in scientific and clinical research. The objectives of biobanking are the creation of unified recommendations on the planning of premises and the selection of equipment for storage; development of management methods and staff training; standardization of methods for the collection, shipping, processing and storage of biomaterial of various origins, as well as methods for quality control and validation of the applied methods; creation and use of databases of information accompanying biospecimens. The lack of common standards for conducting the preanalytical phase has been the cause of low accuracy and poor reproducibility of research results. To date, a large number of guidelines and best practices have been published that provide an answer to a wide range of problems in organizing the biobanking process. The article provides an overview of the most famous biobanking guidelines that can be used to solve various research problems. Biobanking in Russia is actively developing. Since 1996 there is a work on the legislative regulation of biobanking activities, as a result of which a number of regulatory documents have been issued. An important stage in the development of biobanking in Russia was the establishment of the „National Association of Biobanks and Biobanking Specialists” (NASBio) in 2018, which included representatives of medical and research institutions, commercial firms, and qualified specialists in the field of biobanking. One of the key tasks of NASBio is the adaptation and implementation of the best biobanking practices in Russian research institutes and centers. The use of modern guidelines and best practices on biobanking will lead to an increase in the quality of research and publications.Using data obtained from domestic and foreign sources, we formed a set of primers and fluorogenic probes for analyzing twentysix specific sequence polymorphisms and one reference gene. In the course of evaluating the effectiveness of real-time PCR, using the example of one of the markers (S01a), we obtained the optimal amount of DNA per reaction (70 ng), providing a resolution of at least 0.1% of the method with the ability to estimate linear chimerism. Formed panel of primers for genetic polymorphisms – InDel has a high degree of informational content for donor-recipient pairs of Russia. From January 2018 to June 2019, a quantitative assessment of the level of linear (CD3 +, CD34 +) and general chimerism was carried out for 28 patients of the clinic of the Institution. Finally, we analyzed patients who received allografts and present 4 different clinical situations that illustrate the informativity level of this method.Microorganisms are able to form biofilms on surfaces of biotic and abiotic nature. In turn, in human biotopes there are optimal conditions for the implementation of biofilm-forming activity. Moreover, in medical practice, polymeric materials are often used for drainage or prosthetics, which can also be successfully colonized by bacteria. However, in laboratory practice, the formation of biofilms is usually evaluated on glass or polystyrene. The purpose of the study is to evaluate the methodological features of studying the biofilm-forming activity of microorganisms on the surface of synthetic polymeric materials. We used strains of Staphylococcus aureus ATCC 25923, Escherichia coli K-12, Candida albicans ATCC 10231, as well as synthetic polymeric materials – DentLight Flow light-curing composite material (nano-hybrid fluid composite; Russia), glass ionomer chemical curing Fuji 1 (Japan), cement for temporary fixation of orthopedic constructions TempBond NE (USA), acrylic, polyurethane and polyvinyl chloride. laboratory practice.Oral fluid is a unique biological environment, containing a wide range of substances, coming from local and systemic sources, which makes it possible to use it as an object for assessing pathological changes in the body both at the local and systemic levels. In comparison with the traditional method of blood analysis, the advantage of evaluating the parameters of the oral fluid is the non-invasive of this method of obtaining material. All patients underwent oral fluid sampling using special plastic containers with a swab, which facilitate the selection of material, eliminating the penetration of mucin into a clean test sample, which helps to obtain more accurate analysis results. The amount of secretory IgA, lipopolysaccharide-binding protein (LBP), TBA-active products, the level of total antioxidant activity in the oral fluid in individuals with a low level of 25(OH)D before and after taking the native solution of vitamin D „Aqua Trim” were determined. The concentrations of secretory immunoglobulin A, lipopolysaccharide, binding protein and the level of total antioxidant activity are reduced in the oral fluid of people with vitamin D deficiency, but the number of intermediate products of lyoperoxidation increases. The course intake of the native solution of vitamin D (International Nonproprietary Name – Colecalciferol) normalizes the functioning of the immunity of the oral cavity and restores the balance of the „lipid peroxidation-antioxidants” system.An important factor in the pathogenesis of chronic inflammation in periodontitis is endothelial dysfunction (ED). Adhesion molecules are markers of impaired barrier function, adhesive properties and vascular permeability. The study of the concentration of soluble adhesion molecules is very promising in the diagnosis of ED. The purpose of this research was to study changes in the concentration of soluble forms of adhesive molecules of the selectin family and the immunoglobulin superfamily when used as markers of systemic manifestations of ED in the dynamics of the treatment of chronic generalized periodontitis (CP) using surgical and therapeutic schemes. 60 patients with CP (33 women and 27 men) and 20 clinically healthy volunteers (10 men and 10 women) were examined. The state of the endothelium was assessed by the content in the serum of soluble forms of adhesive molecules – sP- and sE-selectins, intercellular adhesive molecules of type 1 (sICAM-1), vascular molecules of cell adhesion of type 1 (VCAM-1) by ELISA.


