scholarly journals Fluorescent Aptamers for Detection and Treatment of Pathogenic Bacteria and Cancer

2021 ◽  
Author(s):  
Aarushi Sharma ◽  
Grace Ramena
Keyword(s):  
Monoclonal Antibodies ◽  
Tumor Cells ◽  
Pathogenic Bacteria ◽  
Production Efficiency ◽  
Design Development ◽  
Step Process ◽  
Diagnostic Assays ◽  
Systematic Evolution ◽  
Exponential Enrichment ◽  
Made In

Issues presented by the application of monoclonal antibodies in diagnostic assays and as curative agents can make the use of such molecules cost-prohibitive and sometimes even unsafe. This has warranted the development of short single-stranded oligonucleotides known as Aptamers. The structural malleability of these short DNA or RNA nucleotide segments allows them to exist in distinct conformations. SELEX (Systematic Evolution of Ligands by Exponential Enrichment) is a multi-step process for synthesis of aptamers. Each step of this procedure is governed by a diverse set of factors that influence production efficiency, binding affinity, and specificity of the oligonucleotides. Headway in aptamer research has been made in recent years by the introduction of newer iterations of the SELEX process. A greater number of studies are now being carried out to incorporate aptamers into existing disease detection tools and therapies. An overview has been given first on the key aptamer properties and the process of their production (with its newer iterations), contrasting each of them with that of monoclonal antibodies. Possible manifold applications afforded due to unique aptamer characteristics are also discussed. A keen review is further provided on the design, development and use of fluorescent aptamers in bioimaging, sequencing or profiling, and treatment of pathogenic bacteria and tumor cells.

scholarly journals Aptamers: An Emerging Class of Molecules That Rival Antibodies in Diagnostics

1999 ◽  
Vol 45 (9) ◽  
pp. 1628-1650 ◽  
Author(s):  
Sumedha D Jayasena
Keyword(s):  
Molecular Recognition ◽  
Emerging Diseases ◽  
Diagnostic Assays ◽  
Wide Range ◽  
Fast Pace ◽  
Target Molecules ◽  
Systematic Evolution ◽  
Diagnostic Applications ◽  
Exponential Enrichment ◽  
Near Future

Abstract Antibodies, the most popular class of molecules providing molecular recognition needs for a wide range of applications, have been around for more than three decades. As a result, antibodies have made substantial contributions toward the advancement of diagnostic assays and have become indispensable in most diagnostic tests that are used routinely in clinics today. The development of the systematic evolution of ligands by exponential enrichment (SELEX) process, however, made possible the isolation of oligonucleotide sequences with the capacity to recognize virtually any class of target molecules with high affinity and specificity. These oligonucleotide sequences, referred to as “aptamers”, are beginning to emerge as a class of molecules that rival antibodies in both therapeutic and diagnostic applications. Aptamers are different from antibodies, yet they mimic properties of antibodies in a variety of diagnostic formats. The demand for diagnostic assays to assist in the management of existing and emerging diseases is increasing, and aptamers could potentially fulfill molecular recognition needs in those assays. Compared with the bellwether antibody technology, aptamer research is still in its infancy, but it is progressing at a fast pace. The potential of aptamers may be realized in the near future in the form of aptamer-based diagnostic products in the market. In such products, aptamers may play a key role either in conjunction with, or in place of, antibodies. It is also likely that existing diagnostic formats may change according to the need to better harness the unique properties of aptamers.

FEATURES OF ORGANOPHOSPHATES IMMOBILIZATION VIA STREPTAVIDIN-BIOTIN SYSTEM FOR EXPERIMENTS ON SELECTION OF APTAMERS

2020 ◽  
pp. 12-20
Author(s):  
D. A. Belinskaya ◽  
Yu. V. Chelusnova ◽  
V. V. Abzianidze ◽  
N. V. Goncharov
Keyword(s):  
Polyethylene Glycol ◽  
Organophosphorus Compounds ◽  
Binding Energies ◽  
Rna Aptamers ◽  
Main Method ◽  
Modeling Methods ◽  
Molecular Dynamics Methods ◽  
Systematic Evolution ◽  
Exponential Enrichment ◽  
Selection Of

Poisoning with organophosphorus compounds occupy one of the leading places in exotoxicosis. At the first stage, the detoxification of organophosphates can be provided with the help of DNA or RNA aptamers that bind the poison in the bloodstream. Currently, the main method of searching for aptamers is the experimental method of systematic evolution of ligands by exponential enrichment (SELEX). In the process of aptamer selection, the target molecule must be immobilized via the streptavidin-biotin complex. Since the poison molecule is small in size, to increase its availability for binding to aptamer, it is necessary to use a spacer between organophosphorus compounds and biotin. The aim of this work was to optimize the selection of aptamers for organophosphorus compounds by increasing the availability of a poison molecule immobilized via the streptavidin-biotin complex on the example of paraoxon. For this purpose, three spacers between organophosphorus compounds and biotin were tested using molecular modeling methods: three links of polyethylene glycol (3-PEG), four links of polyethylene glycol (4-PEG) and aminohexyl. The conformation of the biotinylated paraoxon complex with streptavidin and the interaction of paraoxon with the binding fragment of the aptamer were modeled using molecular docking and molecular dynamics methods. The ability of biotinylated paraoxon to bind to the aptamer has been evaluated by analyzing the surface area of the paraoxon available to the solvent, as well as by calculating the free binding energies. It has been shown that only in the case of aminohexyl immobilized paraoxon can contact the aptamer. At the final stage, the synthesis of paraoxon bound to biotin via aminohexyl was carried out.

Pengembangan Instrumen Penilaian Kinerja Praktikum Organisasi Kehidupan Berbasis Konstruktivisme Kelas VII SMP

2017 ◽  
Vol 6 (2) ◽  
pp. 9-15
Author(s):  
Dewi Febrianty ◽  
Risnita Risnita ◽  
Afreni Hamidah
Keyword(s):  
Performance Assessment ◽  
Positive Response ◽  
Assessment Instrument ◽  
Assessment Instruments ◽  
Development Research ◽  
Design Development ◽  
Teachers And Students ◽  
Assessment Sheet ◽  
Practical Performance ◽  
Made In

Practical performance assessment is an important part of the learning process, but several obstacles are found in its implementation. The objectives of this study are (1) to develop constructivism-based performance assessment instruments for class VII Yunior High School in  Life Organization subject,  (2) to describe aspects that need to be made in constructivism-based practical performance assessment instruments, and (3) to describe teacher responses in using constructivism-based practical performance assessment instruments. This research is a development research using a 4D model, the stages are defining, design, development and distribution. The trial subjects in this study consisted of 10 students for small group trials and 40 students for large group trials. The indicators used in the study include aspects related to the development of constructivist life-based practicum assessment instruments. Instrument used was a questionnaire to reveal the response of teachers and students to practical performance assessment instruments. The results of the data analysis showed that the content feasibility value is 86.31% at the intervals of 48.33 which means it is feasible to use. Most students gave a positive response to the assessment sheet given (96.67%), a small portion gave a negative response (33.3%). Because the average positive response of students is more than 75%, the performance assessment instrument is considered feasible to be applied.

Natural Killer cells and monoclonal antibodies: Two partners for successful antibody dependent cytotoxicity against tumor cells

2021 ◽  
Vol 160 ◽  
pp. 103261
Author(s):  
Mélanie Gauthier ◽  
Caroline Laroye ◽  
Danièle Bensoussan ◽  
Cédric Boura ◽  
Véronique Decot
Keyword(s):  
Monoclonal Antibodies ◽  
Natural Killer Cells ◽  
Natural Killer ◽  
Tumor Cells ◽  
Killer Cells

scholarly journals Role and Modulation of NK Cells in Multiple Myeloma

Hemato ◽  
2021 ◽  
Vol 2 (2) ◽  
pp. 167-181
Author(s):  
Marie Thérèse Rubio ◽  
Adèle Dhuyser ◽  
Stéphanie Nguyen
Keyword(s):  
Multiple Myeloma ◽  
Monoclonal Antibodies ◽  
Nk Cells ◽  
Tumor Cells ◽  
Nk Cell ◽  
Ex Vivo ◽  
Killer Cell ◽  
Proteasome Inhibitors ◽  
Disease Evolution ◽  
Cell Functions

Myeloma tumor cells are particularly dependent on their microenvironment and sensitive to cellular antitumor immune response, including natural killer (NK) cells. These later are essential innate lymphocytes implicated in the control of viral infections and cancers. Their cytotoxic activity is regulated by a balance between activating and inhibitory signals resulting from the complex interaction of surface receptors and their respective ligands. Myeloma disease evolution is associated with a progressive alteration of NK cell number, phenotype and cytotoxic functions. We review here the different therapeutic approaches that could restore or enhance NK cell functions in multiple myeloma. First, conventional treatments (immunomodulatory drugs-IMids and proteasome inhibitors) can enhance NK killing of tumor cells by modulating the expression of NK receptors and their corresponding ligands on NK and myeloma cells, respectively. Because of their ability to kill by antibody-dependent cell cytotoxicity, NK cells are important effectors involved in the efficacy of anti-myeloma monoclonal antibodies targeting the tumor antigens CD38, CS1 or BCMA. These complementary mechanisms support the more recent therapeutic combination of IMids or proteasome inhibitors to monoclonal antibodies. We finally discuss the ongoing development of new NK cell-based immunotherapies, such as ex vivo expanded killer cell immunoglobulin-like receptors (KIR)-mismatched NK cells, chimeric antigen receptors (CAR)-NK cells, check point and KIR inhibitors.

PENGEMBANGAN APLIKASI ANDROID BERBANTU SOFTWARE ISPRING SUITE SEBAGAI MEDIA PEMBELAJARAN EKONOMI MADRASAH ALIYAH MA’ARIF 9 KOTAGAJAH TAHUN PELAJARAN 2018/2019

2021 ◽  
Vol 1 (2) ◽  
pp. 175-187
Author(s):  
Novita Anggestia ◽  
Triani Ratnawuri ◽  
Meyta Pritandhari
Keyword(s):  
Learning Process ◽  
Development Model ◽  
Average Score ◽  
Application Software ◽  
Android Application ◽  
Design Development ◽  
Practical Research ◽  
Android Applications ◽  
Analysis Design ◽  
Made In

  Learning media is one of the needs that must be fulfilled in the learning process. The results of the pre-survey of learning media used in the Aliyah Ma'arif 9 Kotagajah Madrasah, researchers found several problems, namely the use of learning media that were less innovative in learning and the limitation of images in teaching books, worksheets and powerpoints so that students were not attracting attention in the learning process . So that learning media are needed that can attract the attention of students such as android applications, android application software assisted ispring suite as an economic learning media arranged concisely, clearly, and made in a practical form so that students are more interested and enthusiastic in learning and can understand the material. The development model used in this development is the ADDIE development model which consists of several stages, namely (Analysis, Design, Development, Implementation, and Evaluation). Based on the results of the development of android applications assisted by software ispring suite as an economic learning media it is known the results of recapitulation of data that have been carried out by learning media material experts on android applications with an average score of 86% included in the very feasible category and declared valid, the results of recapitulation from media experts with scores on average 87% fall into the category of very decent and declared valid. Furthermore, the practicality test by IPS X grade 1 students of Aliyah Ma'arif 9 Kotagajah gets an average score of 92.2% and falls into the very practical category so that it is declared practical. research shows that economic learning media using this android application is suitable for use in learning. Thus it can be concluded that the learning media of android applications are learning media that are valid and practical to be used in the learning process.

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