China
Africa
Explore chapters and articles related to this topic
Immunochemistry of Cell Wall – a Tool for Evaluation of the Response of Plants to Changed Habitat
Published in Artur Dyczko, Andrzej M. Jagodziński, Gabriela Woźniak, Green Scenarios: Mining Industry Responses to Environmental Challenges of the Anthropocene Epoch, 2022
Katarzyna Sala, Kamila Godel-Jędrychowska, Ewa Kurczyńska
Immunochemistry (ICH) includes immunocytochemistry (ICC) which examines cells and immunohistochemistry (IHC) which examines the tissues. It is a method that allows for identification or localisation of specific antigens within cells or tissues. The method utilises an antigen-specific antibody which binds an antigen in a cell/tissue section, fluorochromes (at the light microscope level) and colloidal-gold particles (at the electron microscopy level) to visualize where the antibody was bound. ICH, nowadays, is a common laboratory technique that is used to visualize the presence of a specific antigen in cells/tissues by use of a specific primary antibody that binds to it. In a two-step reaction, the primary antibody allows for visualization of the antigen under a fluorescence microscope only when it is bound by a secondary antibody that has a conjugated fluorophore (Fig. 2). ICH helps to evaluate whether or not cells/tissues in a particular sample express the antigen in question. In cases where an immunopositive signal is found, we are able to determine which sub-cellular compartments are expressing the antigen.
Analytical Applications of Piezoelectric Crystal Biosensors
Published in Loïc J. Blum, Pierre R. Coulet, Biosensor Principles and Applications, 2019
John H. T. Luong, George G. Guilbault
It is an open question whether gas-to-solid phase immunochemistry can be expected since the antibody-coated crystal exhibits no selectivity in terms of immunochemical reactions. As experimentally demonstrated (52) the performance of the parathion antibody-coated crystal in terms of frequency response and sensitivity to parathion was almost similar to that of the crystal coated with valproic acid antiserum, IgG, and even bovine serum albumin, respectively. In addition, the parathion antibody-coated crystal was responsive to parathion, malathion, disulfoton, toluene, o-nitrotoluene, and valproic acid. Similarly, the behavior of the valproic acid antiserum-coated crystal to valproic acid was identical to that of the crystal coated with parathion antibody, IgG, and bovine serum albumin, respectively. Such data clearly demonstrate that nonspecific chemisorption to antibody must be taken into account in any evaluation of the antibody-based piezoelectric response to antigenic species. It is indeed a difficult task to distinguish the two types of interaction.
*
Published in Valerio Voliani, Nanomaterials and Neoplasms, 2021
Xuan Yang, Miaoxin Yang, Pang Bo, Madeline Vara, Younan Xia
Gold has a substantial history in both biomedicine and biological studies. The first report on the use of Au compounds to treat arthritis appeared in 1934 [41]. It was found that Au salts could reduce inflammation and slow disease progression in patients with rheumatoid arthritis through a procedure known as “gold treatment.” In some patients, the treatment helped relieve joint pain and stiffness, reduce swelling and bone damage, and diminish the chance of joint deformity and disability. Since the 1990s, however, the clinical use of “gold treatment” has dropped significantly due to its numerous side effects and limited efficacy. In the 1950s, Au colloids were evaluated as radiotracers for sentinel lymph node biopsies in humans [42]. In addition, Au nanoparticles have been used extensively in immunochemistry since 1971, when Faulk and Taylor reported a method that involved the conjugation of Au nanoparticles with an antibody for the direct visualization of the surface antigens of salmonellae through electron microscopy [43]. This application is based on the strong attenuation of an electron beam by Au due to its large atomic number. Many studies have been devoted to similar applications of Au nanoparticles (typically, conjugation with a targeting moiety such as antibody, lectin, enzyme, and aptamer, among others) in biochemistry, microbiology, immunology, cytology, and plant physiology [44]. In addition to its ability to weaken the intensity of electron beam, Au can also effectively attenuate other types of high-energy radiation such as X-rays. When Roentgen discovered X-ray radiation in 1895, he noticed that the Au ring on his wife’s finger gave greater X-ray attenuation than her bones in the X-ray image taken [45]. This was the first known demonstration of Au as a tracer or contrast agent for radiology. In recent years, many types of Au nanomaterials have been developed for such applications [16].
Theoretical aspects of peptide imprinting: screening of MIP (virtual) binding sites for their interactions with amino acids, di- and tripeptides
Published in Journal of the Chinese Advanced Materials Society, 2018
Julie Settipani, Kal Karim, Alienor Chauvin, Si Mohamed Ibnou-Ali, Florian Paille-Barrere, Evgeny Mirkes, Alexander Gorban, Lee Larcombe, Michael J. Whitcombe, Todd Cowen, Sergey A. Piletsky
The use of terminal sequences of target proteins as a surrogate template for the whole macromolecule was first proposed by Rachkov and Minoura in 2000. [1] They demonstrated that materials capable of binding the nonapeptide oxytocin, under aqueous conditions, could be prepared by imprinting a tetrapeptide with the same three amino acid residues in the N-terminus (Pro-Leu-Gly-NH2). The epitope approach was soon adapted by others to prepare materials capable of recognizing larger proteins, such as cytochrome c and even viruses. The concept of an ‘epitope’ has been borrowed from immunochemistry. In that context, it is the region of an antigen that is recognized by the variable domain of an antibody and could span adjacent residues on the antigen surface that are non-adjacent in the primary sequence. In imprinting terms however we normally mean an epitope to be a peptide with a single sequence (taken from the primary sequence of the target) that, when used as a template, generates a selective imprint for the said target. While many examples are terminal sequences, for some targets the protein termini may be inaccessible and a loop or other surface displayed region may be selected. A further advantage of using the epitope approach is that it is not necessary to isolate the target protein to use as template, provided that some structural information is known.
Study of functional drug-eluting stent in promoting endothelialization and antiproliferation
Published in Journal of Biomaterials Science, Polymer Edition, 2020
Ruixia Hou, Leigang Wu, Yabin Zhu, Jin Wang, Zhilu Yang, Qiufen Tu, Nan Huang
Fibrinogen denaturation: the fibrinogen adsorption was analyzed by incubating the specimen with 50 μL of platelet-poor plasma (PPP) at 37 °C for 2 h. The activation of the adsorbed fibrinogen was determined by the exposure of the γ chain via indirect immunochemistry using a sensitive primary antibody (Accurate Chemical).