China
Africa
Explore chapters and articles related to this topic
Nanotechnological Interventions for Neurodegenerative Disorders Using Phytoactives
Published in Bhupinder Singh, Om Prakash Katare, Eliana B. Souto, NanoAgroceuticals & NanoPhytoChemicals, 2018
Sumant Saini, Charan Singh, Shikha Lohan, Atul Jain, Eliana B. Souto, Bhupinder Singh
The influx and efflux of proteins across the nuclear barrier play a key role in the normal functioning of the neurons. This process is controlled by a number of signals; these include nuclear localization signal class 1 (NLS 1) in protein import, nuclear export signal (NES) for protein export, importins and karyopherins for transport receptors, nuclear protein complexes (NPCs) such as nucleoporins (Nups), and Ran GTPase-activating protein (RanGAP). A balance between the influx and efflux of cargo exists at the nuclear pore. Impairment of this machinery by any means causes damage to the nuclear physiology, which subsequently induces neurodegeneration. Increase in the leakiness of the nuclear barrier affects the nucleocytoplasmic transport, changes protein localization across the nuclear coat, and is likely to be involved in Ca2+-mediated apoptosis (Sheffield et al., 2006; Bano et al., 2010).
General Introductory Topics
Published in Vadim Backman, Adam Wax, Hao F. Zhang, A Laboratory Manual in Biophotonics, 2018
Vadim Backman, Adam Wax, Hao F. Zhang
The nuclear pores are large (about 100 nm in diameter) and serve to facilitate the exchange of materials between the nucleus and the cytoplasm. This exchange is a critically important process as a part of gene expression, as we will soon see. The exchanged molecules include various transcription factors going into the nucleus to regulate gene transcription and messenger RNA (mRNA) getting out of the nucleus to be read by the ribosomes in the cytoplasm as part of the translation process leading to protein synthesis. These processes are discussed later in more detail. The number of nuclear pores correlates with the metabolic activity of a cell. A metabolically silent cell may have as few as dozens of pores, whereas an active cell may have as many as thousands. Another function of nuclear pores is that they fuse the outer and the inner nuclear membranes; indeed, nuclear pores are not simple “holes” in the envelope but rather protein complexes called nucleoporins. Yet another function of the pores is active transport. Although small molecules freely diffuse through the pores, larger molecules are recognized by specific sequences, and their diffusion is assisted with the help of nucleoporins, which is known as the RAs-related nuclear protein cycle or RAN cycle.
Single Molecule Fluorescence
Published in Yuri L. Lyubchenko, An Introduction to Single Molecule Biophysics, 2017
Another interesting area that has seen a lot of work is that of motor and DNA-associated proteins moving along their tracks, which are important in many cellular functions. We briefly mentioned the work of Kinosita and coworkers on the rotary motor F1-ATPase (Noji et al. 1997). In this study, the authors immobilized individual ATPase molecules and directly recorded their movement using fluorescence imaging. Further studies directly revealed the rotary movement of this protein and complex stepping patterns that accompanied its biochemical functions. A more recent example is the study by Myong et al. (2005), where they studied the movement of Rep helicase on DNA. Their interesting observation was that the protein moved along single-stranded DNA until it ran into double-stranded DNA, whereupon it dissociated and restarted the cycle. The study is also noteworthy because it used an interesting fluorescence enhancement induced by proximity of the protein. Recent photophysical studies have provided support for a mechanism for the enhancement being a reduction in cis-trans isomerization of the fluorescent dye due to steric interactions with the protein (Stennett et al. 2015). More recent studies have used DNA curtains, and observed what happens when proteins moving along DNA encounter other proteins, with several outcomes observed that may be particularly relevant for the situation in a cell (Lee et al. 2014).
Applying Bioaffordances through an Inquiry-Based Model: A Literature Review of Interactive Biodesign
Published in International Journal of Human–Computer Interaction, 2021
Phillip Gough, Soojeong Yoo, Martin Tomitsch, Naseem Ahmadpour
Dyson (2007) predicted that the 21st Century will be known as the century of biology, in much the same way as the 20th Century was the century of physics. One could argue that we have already seen evidence of this prediction in the form of breakthrough advances in life sciences that mirror the leaps in physics in the early 20th Century, such as CRISPR-Cas9 gene engineering technology (Ran et al., 2015). Some discoveries have as yet unknown applications, but great potential, such as hachimoji DNA, with which DNA can be encoded using eight base pairs, instead of the naturally occurring four (Hoshika et al., 2019). Another recent breakthrough is the design and manufacture of the first organisms that can be described as reconfigurable, living robots, built out of living cells (Kriegman et al., 2020). This is a physical manifestation of research that is reminiscent of the virtual experiments presented about 25 years ago by Sims (1994). What was once scientific simulation is now becoming a biological reality. This exciting and challenging life science research presents new opportunities for the design of interactive products.
How surfaces of carbon fiber reinforced plastics with thermoset matrices need to be treated for structural adhesive bonding
Published in The Journal of Adhesion, 2020
SLS specimens failed due to stress concentration at the overlap ends. The cracks ran in the first adherent (CFRP) layer and not in the adhesive-adherent interphase. For the CATT samples, the same failure mode was observed. So, the adherent’s material is mainly tested by the testing methods. For the untreated DCB samples a change of the adhesion failure from one adherent to the other due to the thin adhesive layer was observed. Treated DCB specimens failed mainly in the middle of the 100 µm thick adhesive layer. Here, mainly the fracture behavior of the used adhesive was tested. The fracture behavior can be influenced significantly by the incorporated fillers (also by the often-used carrier meshes of aerospace film adhesives). For example, in [23] it was shown that fracture energy of DCB samples can be raised up to 69% with the addition of graphene oxide nanoplatelets into the adhesive layer.
Inflammatory bowel disease: why this provides a useful example of the evolving science of nutrigenomics
Published in Journal of the Royal Society of New Zealand, 2020
Early studies analysed specific hypothesised genetic variants as single nucleotide polymorphisms (SNPs), linked to disease risk (Satsangi et al. 1994, 1996). However, subsequent studies used whole genome scans as genome-wide association studies (GWAS) (e.g. Karban et al. 2004; Low et al. 2004; Mathew and Lewis 2004). These studies examine SNPs across the genome, and require large numbers of subjects. In a number of these studies, IBD proved to be a good illustrative example of technology developments in defining the causes of genetic susceptibility. There was also good evidence that diet played an important role in the disease, but considerable confusion as to the best dietary advice to give (e.g. Harries and Rhodes 1985; Rhodes and Rose 1986; Gassull and Cabré 2001). For these reasons, the disease was selected as the prototype example of gene-diet interactions in the government-funded Nutrigenomics New Zealand (NuNZ) programme, which ran between 2004 and 2014.