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Topic Review
Coumarin-Based Profluorescent and Fluorescent Substrates
Activities of xenobiotic-metabolizing enzymes have been measured with various in vitro and in vivo methods, such as spectrophotometric, fluorometric, mass spectrometric and radioactivity-based techniques. In fluorescence-based assays, the reaction produces a fluorescent product from a nonfluorescent substrate or vice versa. We describe here historical highlights and current use of (pro)fluorescent coumarin derivatives in evaluating activities of the major types of xenobiotic-metabolizing enzyme systems. Traditionally coumarin substrates have been used to measure oxidative activities of cytochrome P450 (CYP) enzymes. For this purpose, profluorescent coumarins are very sensitive, but generally lack selectivity for individual CYP forms. The entry describes several new coumarin-based substrates for measuring activities of CYP and conjugating enzymes with improved selectivity.
  • 3.1K
  • 14 Jul 2020
Topic Review
Acacia spp.
The genus Acacia belongs to the subfamily Mimosoideae of the family Fabaceae. It comprises a large group of more than 1350 species, widely distributed throughout tropical and warm temperate areas of the world. Most of the species are native to Australia but are spread all over the world because of their wide variety of uses and economic importance such as for ornamental purposes, for sand and dune stabilization, as a fuel through the production of woodfuel and charcoal, as an important source of fodder, tannins for the leather industry, gums, and essences for perfumes.
  • 3.1K
  • 10 Feb 2021
Topic Review
Solution-Processed Organic Phototransistors and Their Recent Developments
Today, more disciplines are intercepting each other, giving rise to “cross-disciplinary” research. Technological advancements in material science and device structure and production have paved the way towards development of new classes of multi-purpose sensory devices. Organic phototransistors (OPTs) are photo-activated sensors based on organic field-effect transistors that convert incident light signals into electrical signals. The organic semiconductor (OSC) layer and three-electrode structure of an OPT offer great advantages for light detection compared to conventional photodetectors and photodiodes, due to their signal amplification and noise reduction characteristics. Solution processing of the active layer enables mass production of OPT devices at significantly reduced cost. The chemical structure of OSCs can be modified accordingly to fulfil detection at various wavelengths for different purposes. Organic phototransistors have attracted substantial interest in a variety of fields, namely biomedical, medical diagnostics, healthcare, energy, security, and environmental monitoring. Lightweight and mechanically flexible and wearable OPTs are suitable alternatives not only at clinical levels but also for point-of-care and home-assisted usage.
  • 3.1K
  • 27 Jan 2022
Topic Review
Red Seaweed Pigments
Algae taxa are notably diverse regarding pigment diversity and composition, red seaweeds (Rhodophyta) being a valuable source of phycobiliproteins (phycoerythrins, phycocyanin, and allophycocyanin), carotenes (carotenoids and xanthophylls), and chlorophyll a. These pigments have a considerable biotechnological potential, which has been translated into several registered patents and commercial applications. 
  • 3.1K
  • 20 Jan 2022
Topic Review
Glucosinolates
Glucosinolates (GSLs) are secondary plant metabolites abundantly found in plant order Brassicales. GSLs are constituted by an S-β-d-glucopyrano unit anomerically connected to O-sulfated (Z)-thiohydroximate moiety. The side-chain of the O-sulfate thiohydroximate moiety, which is derived from a different amino acid, contributes to the diversity of natural GSL, with more than 130 structures identified and validated to this day. Both the structural diversity of GSL and their biological implication in plants have been biochemically studied. While intact GSLs are biologically inactive, various products, including isothiocyanates, nitriles, epithionitriles, and cyanides obtained through enzyme-catalyzed hydrolysis of GSLs, exhibit many different biological activities, among which several therapeutic benefits have been suggested. 
  • 3.1K
  • 12 Oct 2020
Topic Review
Aspartate in Cell Proliferation and Survival
Aspartate is a precursor for nucleotide synthesis and  is indispensable for cell proliferation. Moreover, the malate–aspartate shuttle plays a key role in redox balance, and a deficit in aspartate can lead to oxidative stress. It is now recognized that aspartate biosynthesis is largely governed by mitochondrial metabolism, including respiration and glutaminolysis in cancer cells. Therefore, under conditions that suppress mitochondrial metabolism, including mutations, hypoxia, or chemical inhibitors, aspartate can become a limiting factor for tumor growth and cancer cell survival.
  • 3.1K
  • 15 Jul 2022
Topic Review Peer Reviewed
SARS, MERS and COVID-19-Associated Renal Pathology
Coronaviruses are a large group of RNA viruses, the most notable representatives of which are SARS-CoV, MERS-CoV and SARS-CoV-2. Human coronavirus infections were first documented in the 1960s, when members causing seasonal common colds were successfully replicated in human embryonal trachea and kidney cell cultures and classified based on electron microscopy. The history of coronaviruses stretched far back to that point, however, with some representatives causing disease in animals identified several decades prior and evolutionary data pointing towards the origin of this viral group more than 55 million years ago. In the short time period of research since they were discovered, coronaviruses have shown significant diversity, genetic peculiarities and varying tropism, resulting in the three identified causative agents of severe disease in humans—SARS, MERS and the most recent one, COVID-19, which has surpassed the previous two due to causing a pandemic resulting in significant healthcare, social and political consequences. Coronaviruses are likely to have caused pandemics long before, such as the so-called Asian or Russian influenza. Despite being epitheliotropic viruses and predominantly affecting the respiratory system, these entities affect multiple systems and organs, including the kidneys. In the kidneys, they actively replicate in glomerular podocytes and epithelial cells of the tubules, resulting in acute kidney injury, seen in a significant percentage of severe and fatal cases. Furthermore, the endothelial affinity of the viruses, resulting in endotheliitis, increases the likelihood of thrombotic microangiopathy, damaging the kidneys in a two-hit mechanism. As such, recently, COVAN has been a suggested nomenclature change indicating renal involvement in coronavirus infections and its long-lasting consequences. 
  • 3.1K
  • 10 Oct 2022
Topic Review
The NifA–NifL System for Nitrogen Fixation
Nitrogen–fixing bacteria execute biological nitrogen fixation through nitrogenase, converting inert dinitrogen (N2) in the atmosphere into bioavailable nitrogen. Elaborating the molecular mechanisms of orderly and efficient biological nitrogen fixation and applying them to agricultural production can alleviate the “nitrogen problem”. Azotobacter vinelandii is a well–established model bacterium for studying nitrogen fixation, utilizing nitrogenase encoded by the nif gene cluster to fix nitrogen. In Azotobacter vinelandii, the NifA–NifL system fine–tunes the nif gene cluster transcription by sensing the redox signals and energy status, then modulating nitrogen fixation. 
  • 3.1K
  • 06 Feb 2023
Topic Review
Buddhist Tantras
The Buddhist Tantras are a varied group of Indian and Tibetan texts which outline unique views and practices of the Buddhist tantra religious systems.
  • 3.1K
  • 14 Oct 2022
Topic Review
Land Use Transitions
Land use transition refers to the changes in land use morphologies, including dominant morphology and recessive morphology, of a certain region over a certain period of time driven by socio-economic change and innovation, and it usually corresponds to the transformation of the socio-economic development stage. The dominant morphology refers to the land use structure with features such as the quantity and spatial pattern of land use types. While the recessive morphology includes the land use features in the aspects of quality, property rights, management mode, input, output and function.
  • 3.1K
  • 17 Sep 2021
Topic Review
Proposed Melbourne Rail Extensions
Several proposals have been put forward by various groups to expand the Melbourne rail network—proposals for additional rail lines, extensions to existing lines, as well as electrification to existing lines and new stations on existing lines. Some of these plans were so seriously considered at various times that they appeared in the Melway street directory, and on suburban train destination rolls.
  • 3.1K
  • 31 Oct 2022
Topic Review
Lifshitz Theory of Van Der Waals Force
In condensed matter physics and physical chemistry, the Lifshitz theory of van der Waals forces, sometimes called the macroscopic theory of van der Waals forces, is a method proposed by Evgeny Mikhailovich Lifshitz in 1954 for treating van der Waals forces between bodies which does not assume pairwise additivity of the individual intermolecular forces; that is to say, the theory takes into account the influence of neighboring molecules on the interaction between every pair of molecules located in the two bodies, rather than treating each pair independently.
  • 3.1K
  • 03 Nov 2022
Topic Review
Homogeneity
In physics, a homogeneous material or system has the same properties at every point; it is uniform without irregularities. A uniform electric field (which has the same strength and the same direction at each point) would be compatible with homogeneity (all points experience the same physics). A material constructed with different constituents can be described as effectively homogeneous in the electromagnetic materials domain, when interacting with a directed radiation field (light, microwave frequencies, etc.). Mathematically, homogeneity has the connotation of invariance, as all components of the equation have the same degree of value whether or not each of these components are scaled to different values, for example, by multiplication or addition. Cumulative distribution fits this description. "The state of having identical cumulative distribution function or values".
  • 3.1K
  • 15 Nov 2022
Topic Review
Applications of Facial Scanners in Dentistry
Facial scanning accuracy has proven to be clinically acceptable for use in dental applications. Accuracy is measured by comparing the scan to a control model and measuring the deviations between the two. Scanners with deviation values less than 2 mm are considered acceptable. Deviation values for facial scanners range between 140 and 1330 μm. Reported accuracy for most facial scanners was approximately 500 μm, which is within the limits for clinical acceptability. 
  • 3.1K
  • 06 Dec 2022
Topic Review
Fluid Reaction Models
In the fluidized bed system, the performance of the reactor is affected by the hydrodynamic behaviors of the reactor in that fluid dynamics affects both heat and mass transfer.
  • 3.1K
  • 28 Jul 2021
Topic Review
Strain Rate Sensitivity
Strain rate is a parameter related with dynamic loading phenomena, which are common in industrial applications.
  • 3.1K
  • 06 Sep 2021
Topic Review
Using CNSL for the Synthesis of Surfactants
Cashew Nut Shell Liquid (CNSL) is a promising non-edible renewable resource, directly extracted from the shell of the cashew nut. The interesting structure of CNSL and its components (cardanol, anacardic acid and cardol) lead to the synthesis of biobased surfactants. 
  • 3.1K
  • 10 Mar 2022
Topic Review
Regulationary Factors of the Peroxisomal β-Oxidation
Beta-oxidation(β-oxidation) is an important metabolic process involving multiple steps by which fatty acid molecules are broken down to produce energy. The very long-chain fatty acids (VLCFAs), a type of fatty acid (FA), are usually highly toxic when free in vivo, and their oxidative metabolism depends on the peroxisomal β-oxidation. Although peroxisomal β-Oxidation attracts less research than mitochondria, the importance of the peroxisomal β-oxidation molecular mechanism can still be spotted from some mechanisms involved in upstream regulation.
  • 3.1K
  • 07 Jul 2022
Topic Review
Eurypterus
Eurypterus (/jʊəˈrɪptərəs/ yoo-RIP-tər-əs) is an extinct genus of eurypterid, a group of organisms commonly called "sea scorpions". The genus lived during the Silurian period, from around 432 to 418 million years ago. Eurypterus is by far the most well-studied and well-known eurypterid. Eurypterus fossil specimens probably represent more than 95% of all known eurypterid specimens. There are fifteen species belonging to the genus Eurypterus, the most common of which is E. remipes, the first eurypterid fossil discovered and the state fossil of New York. Members of Eurypterus averaged at about 13 to 23 cm (5 to 9 in) in length, but the largest individual discovered was estimated to be 60 cm (24 in) long. They all possessed spine-bearing appendages and a large paddle they used for swimming. They were generalist species, equally likely to engage in predation or scavenging.
  • 3.1K
  • 09 Nov 2022
Topic Review
Metastatic Dissemination in Lung Carcinogenesis
The tumor microenvironment plays a key role in the progression of lung tumorigenesis, progression, and metastasis. Recent data reveal that disseminated tumor cells (DTCs) appear to play a key role in the development and progression of lung neoplasiaby driving immune system dysfunction and established immunosuppression, which is vital for evading the host immune response.
  • 3.1K
  • 11 Aug 2022
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