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Understanding the Role of Existing Technology in the Fight Against COVID-19
Published in Ram Shringar Raw, Vishal Jain, Sanjoy Das, Meenakshi Sharma, Pandemic Detection and Analysis Through Smart Computing Technologies, 2022
Plasmonic biosensors may offer reliable detection of COVID-19 virus as well. The localized surface plasmon resonance (LSPR)-based sensors have been used to detect clinical analytes [32]. The LSPR refers to the coherent oscillations induced by the photons in the conducting surface electrons. This localized plasmonic resonance can be modulated as a result of change in certain properties such as refractive index and molecular binding. A dual functional plasmonic biosensor was tested by Qiu et al. [33]. The device was capable of inducing plasmonic photothermal (PPT) effect by using gold nanoparticle islands. The nanoparticles strongly absorb the photons and cause localized heating due to non-radiative emission. This phenomenon is used for the hybridization of the nucleic acid strands. The LSPR is then used for the detection of the COVID-19 virus.
Extrahepatic Synthesis of Acute Phase Proteins
Published in Andrzej Mackiewicz, Irving Kushner, Heinz Baumann, Acute Phase Proteins, 2020
Gerhard Schreiber, Angela R. Aldred
Northern analysis and dot-blot hybridization only allow an approximate, relative quantitation of RNA. Molecular titration of specific mRNA is possible if hybridization is carried out in solution and followed by ribonuclease protection assay.54 The antisense RNA used for hybridization can be synthesized in vitro with SP6 RNA polymerase to a given specific radioactivity.55 The principle of this assay is illustrated in Figure 9. It is possible to include an unrelated, tritiated RNA of size similar to the specific RNA as an internal standard for determination of yield. In this way, it has been possible to obtain precise values for the amount of transthyretin mRNA in micrograms or micromoles per gram of wet weight of tissue for both liver and choroid plexus in rats56 and chickens.57 The values obtained for both liver and choroid plexus are summarized in Table 1.
Methods of Evaluation in Orthopaedic Animal Research
Published in Yuehuei H. An, Richard J. Friedman, Animal Models in Orthopaedic Research, 2020
Hybridization is the process of matching complementary strands of DNA or RNA or both to form a double stranded molecule. In situ hybridization (ISH) is the hybridization of a DNA or RNA probe to a target molecule that has not been extracted from its original cellular location, within a chromosome or in a fixed tissue section.253 Immunohistochemistry is analogous to ISH for nucleic acids and is used to detect the distribution of a specific protein within a cell or tissue. In immunohistochemistry, a specific antibody serves as the probe to detect the protein of interest. Gel electrophoresis is a method of separating DNA, RNA, or protein molecules based on their size and electrical charge. This technique makes use of the fact that, under an electrical field small molecules migrate through a gel matrix (agarose or acrylamide) faster than larger molecules. Southern blotting or transfer is a technique which is used to transfer DNA that has been electrophoresed through an agarose gel onto a solid support for hybridization. Northern blotting or transfer is the process of transferring RNA onto a solid filter support for hybridization. Western blotting or transfer is the process of transferring proteins that have been electrophoresed through an acrylamide gel onto a solid filter support for detection of a specific protein by antibody labeling.
An insight into clinical and laboratory detections for screening and diagnosis of cervical cancer
Published in Expert Review of Molecular Diagnostics, 2023
Shruthi Padavu, Pooja Aichpure, Ballamoole Krishna Kumar, Anoop Kumar, RadhaKanta Ratho, Shipra Sonkusare, Indrani Karunasagar, Iddya Karunasagar, Praveen Rai
The nucleic acid-based detection of HPV has resulted in a significant revolution in the discovery of novel HPV types, epidemiological research, facilitation of diagnosis in the healthcare system, and monitoring immunization programs. The main objective of these assays is to identify HPV DNA from cervical samples due to their high sensitivity and specificity [38]. The error-free identification and typing of HPVs are essential for accurately predicting the premalignant state of cervical cancer. PCR, qPCR, and isothermal nucleic acid amplification tests are some of the most frequently used methods for detecting HPV DNA as an etiological agent of cervical cancer [39]. Based on their principles, these molecular detection tests can be classified into two categories: a) nucleic acid hybridization tests, and b) nucleic acid amplification tests. Many diagnostic kits approved by the Food and Drug Administration (FDA) based on nucleic acid detection techniques are commercially available. Table 2 lists the principles and applications of different such kits to detect HR-HPV.
miRNAs as attractive diagnostic and therapeutic targets for Familial Mediterranean Fever
Published in Modern Rheumatology, 2021
Hamza Malik Okuyan, Mehmet A. Begen
Northern Blot Hybridization is a laborious, time-consuming and low-sensitivity method for miRNAs detection. The method includes gel electrophoresis, membrane transfer, cross-linking and probe hybridization steps [102,103]. Next-generation sequencing (NGS) is an advanced technique that enables the quantification of known miRNA and the identification of novel miRNAs. Currently, the use of NGS is limited in clinical settings due to its high cost and bioinformatics analysis requirements [101,104]. Microarrays, based on the nucleic acid hybridization method, are one of the most frequently used methods with low-cost for expression profiling of miRNAs. Microarrays enable the profiling of a large number of miRNAs in a single operation and preferably can be used to compare healthy and patients groups. However, it usually requires validation by another method such as qRT-PCR due to restricted specificity caused by cross-hybridization during microarray [80,101,102]. qRT-PCR is a highly sensitive technique, considered as the gold standard for quantification of gene expression and widely used in genetic laboratories [101]. This method allows the detection of a very small alteration of miRNAs expressions thanks to its high sensitivity, specificity, reproducibility, and accuracy [80]. Also, widely available commercial ready to use kits simplify the use of this technique. The detection of miRNA expression by qRT-PCR includes a reverse transcription of miRNA to cDNA, then, amplification of the target gene with qPCR [102].
Cytogenetic and molecular genetic methods for chromosomal translocations detection with reference to the KMT2A/MLL gene
Published in Critical Reviews in Clinical Laboratory Sciences, 2021
Nikolai Lomov, Elena Zerkalenkova, Svetlana Lebedeva, Vladimir Viushkov, Mikhail A. Rubtsov
The next group of methods aims to detect certain DNA/RNA sequences in the studied samples by the hybridization of nucleotide probes of known composition. Probes are visualized with fluorescence or radioautographic tags. Hybridization methods can be applied to search for sequences of interest in a broad range of lengths—from hundreds to millions of base pairs. Depending on the size of the probes, more or less strict matches in the nucleotide sequence are allowed. This enables detection of the desired sequence even in the presence of nucleotide substitutions and indels. These methods are applicable for almost any type of biological material, such as isolated DNA or RNA, cells, as well as tissues, and are fairly undemanding for the quality of biological material. The overall performance is usually faster than karyotyping.