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Topic Review
Trending Methods for Rapid Cannabinoids Detection
Roadside testing of illicit drugs such as tetrahydrocannabinol (THC) requires simple, rapid, and cost-effective methods. The need for non-invasive detection tools has led to the development of selective and sensitive platforms, able to detect phyto- and synthetic cannabinoids by means of their main metabolites in breath, saliva, and urine samples. One may estimate the time passed from drug exposure and the frequency of use by corroborating the detection results with pharmacokinetic data. Modified surfaces can also act as filters that allow only the target analyte to participate in the electrode reaction. In the case of cannabinoids, as in the case of other drugs, the investigation of the mechanism of action within the organism is the basis of biosensor development.
  • 873
  • 18 Nov 2022
Topic Review
Chitosan and Fibroin
For the creation of tissue-engineered structures based on natural biopolymers with the necessary chemical, physical, adhesive, morphological, and regenerative properties, biocompatible materials based on polysaccharides and proteins are used.  This entry is devoted to a problem of the technology of polymeric materials for biomedical purposes: the creation of biopolymer tissue engineering matrix and the development of a methodology for studying morphology and functional properties of their surface to establish the prospects for using the material for contact with living objects.
  • 864
  • 12 Apr 2021
Topic Review
Nitration of Proteins/Lipids/DNA by Peroxynitrite Derivatives
In recent years, much interest has been generated by the idea that nitrosative stress plays a role in the aetiology of human diseases, such as atherosclerosis, inflammation, cancer, and neurological diseases. The chemical changes mediated by reactive nitrogen species (RNS) are detrimental to cell function, because they can cause nitration, which can alter the structures of cellular proteins, DNA, and lipids, and hence, impair their normal function. One of the most potent biological nitrosative agents is peroxynitrite (ONOO−), which is produced when nitric oxide (•NO) and superoxide (•O2−) are combined at extremely rapid rates. Considering the plethora of oxidations by peroxynitrite, this makes peroxynitrite the most prevalent nitrating species responsible for protein, DNA, and lipids nitration in vivo. There is biochemical evidence to suggest that the interactions of the radicals NO and superoxide result in the formation of a redox system, which includes the reactions of nitrosation and nitration, and is a component of the complex cellular signalling network. However, the chemistry involved in the nitration process with peroxynitrite derivatives is poorly understood, particularly for biological molecules, such as DNA, proteins, and lipids.
  • 863
  • 27 Sep 2022
Topic Review
Betulin
Betulin is an important triterpenoid substance isolated from birch bark, which, together with its sulfates, exhibits important bioactive properties. Using the potentiometric titration method, the product of acidity constants K1 and K2 of a solution of the betulin disulfate H+ form has been found to be 3.86 × 10–6 ± 0.004. It has been demonstrated by the thermal analysis that betulin and the betulin disulfate sodium salt are stable at temperatures of up to 240 and 220 °C, respectively. 
  • 862
  • 28 Feb 2022
Topic Review
Physical Properties of Succinoglycan
Succinoglycan is a type of bacterial anionic exopolysaccharide produced from Rhizobium, Agrobacterium, and other soil bacteria. The exact structure of succinoglycan depends in part on the type of bacterial strain, and the final production yield also depends on the medium composition, culture conditions, and genotype of each strain. Various bacterial polysaccharides, such as cellulose, xanthan, gellan, and pullulan, that can be mass-produced for biotechnology are being actively studied.
  • 853
  • 24 Jan 2022
Topic Review
Protein Caging Tools for Protein Photoactivation
In biosciences and biotechnologies, it is recently critical to promote research regarding the regulation of the dynamic functions of proteins of interest. Light-induced control of protein activity is a strong tool for a wide variety of applications because light can be spatiotemporally irradiated in high resolutions. Therefore, synthetic, semi-synthetic, and genetic engineering techniques for photoactivation of proteins have been actively developed. As a solution for overcoming barriers in conventional ones, researchers' recent approaches in which proteins were chemically modified with biotinylated caging reagents are introduced to photo-activate a variety of proteins without genetic engineering and elaborate optimization.
  • 853
  • 21 Apr 2022
Topic Review
Peptide Libraries with Antimicrobial Activity
Authors describe how by coupling emerging in silico and experimental tools it is possible to create novel peptide libraries with potential antimicrobial activity. This is in response to the growing public health concern pose by multiresistant microbial strains that take millions of lives annually on a global scale. The in silico tools include emerging artificial intelligence algorithms that allow searching for novel sequences in extremely large databases. Once identified, the required membrane activity can be estimated by looking at the interactions with model lipid bilayers via molecular dynamics (MD) simulations. Experimentally, the sequences can be expressed on the surface of yeasts by the surface display technology and subsequently screened in a high-throughput manner aided by microfluidic systems capable of separating out the most active peptides by precisely monitoring changes in optical properties in-line and real-time. 
  • 843
  • 24 May 2021
Topic Review
Oxidative Quality of Dairy Powders
Lipid oxidation (LO) is a primary cause of quality deterioration in fat-containing dairy powders and is often used as an estimation of a products shelf-life and consumer acceptability. The LO process produces numerous volatile organic compounds (VOC) including aldehydes, ketones and alcohols, which are known to contribute to the development of off-flavours in dairy powders. The main factors influencing the oxidative state of dairy powders and the various analytical techniques used to detect VOC as indicators of LO in dairy powders are outlined.
  • 835
  • 19 Oct 2021
Topic Review
NIR-II Aggregation-Induced Emission Luminogens for Tumor Phototheranostics
Various modalities are involved in phototheranostic systems, including therapeutic methods such as photodynamic therapy (PDT) and photothermal therapy (PTT), and diagnostic technologies such as photothermal imaging (PTI), photoacoustic imaging (PAI), and fluorescence imaging (FLI). As an emerging strategy for cancer treatments via generating reactive oxygen species (ROS) with the assistance of light, tissue oxygen, and photosensitizer (PS), PDT has a remarkable light-controllable ability, specific spatiotemporal selectivity, and minimized invasiveness. Second near-infrared (NIR-II) fluorophores possess the capability of surmounting the inherent deficiencies of conventional FLI, by virtue of its remarkable features including deep penetration, reduced tissue scattering, minimal damage, and high spatial resolution endowed by the extremely long wavelength.
  • 834
  • 16 Feb 2022
Topic Review
Mechanisms of α-Syn Aggregation In Vitro
The aggregation of proteins into amyloid fibers is linked to more than forty still incurable cellular and neurodegenerative diseases such as Parkinson’s disease (PD), multiple system atrophy, Alzheimer’s disease and type 2 diabetes, among others. The process of amyloid formation is a main feature of cell degeneration and disease pathogenesis. Despite being methodologically challenging, a complete understanding of the molecular mechanism of aggregation, especially in the early stages, is essential to find new biological targets for innovative therapies. Here, chemical and biophysical methodologies that provided insights on Alpha-synuclein aggregation that would help to investigate other less-known aggregation-prone peptides and proteins were presented.
  • 834
  • 03 Jan 2023
Topic Review
Macrocyclic Receptors
An important direction in the design of tetrapyrrole macrocyclic receptors for a certain substrate type is modification of the macrocycle periphery with bulky substituents or molecular fragments of different natures. Bulky highly-branched lateral substituents are capable of forming additional complexing cavities that can be used for identification and selective binding of substrates of a certain type.
  • 826
  • 14 Sep 2021
Topic Review
Electrochemical Determination of Kynurenine Pathway Metabolites
Kynurenine pathway (KP) is the major catabolic route of tryptophan, which generates an important enzyme cofactor (NAD+) and a variety of bioactive metabolites (so-called kynurenines) with immunosuppressive functions or neuroprotective, antioxidant, and toxic properties. It is involved in a variety of physiological processes, especially in conditions associated with immune dysfunction, central nervous system disorders, autoimmunity, infection, diabetes, and cancer. In normal conditions, tryptophan depletion via KP is initiated by the liver enzyme tryptophan 2,3-dioxygenase (TDO) and the extrahepatic enzyme - indoleamine 2,3-dioxygenase  (IDO) that contributes minimally to this process (5–10%). The extrahepatic KP becomes quantitatively more significant under conditions of immune activation. KP metabolites are frequently found in biofluids, tissues, and cell-delivered material at low nanomolar or low micromolar concentration levels. However, in disease conditions, abnormal tryptophan metabolism can be accompanied by changes in levels of KP metabolites.
  • 825
  • 17 Nov 2021
Topic Review
Dental Implant Nano-Engineering
Titanium (Ti) and its alloys offer favorable biocompatibility, mechanical properties and corrosion resistance, which makes them an ideal material choice for dental implants. However, the long-term success of Ti-based dental implants may be challenged due to implant-related infections and inadequate osseointegration. With the development of nanotechnology, nanoscale modifications and the application of nanomaterials have become key areas of focus for research on dental implants. Surface modifications and the use of various coatings, as well as the development of the controlled release of antibiotics or proteins, have improved the osseointegration and soft-tissue integration of dental implants, as well as their antibacterial and immunomodulatory functions.
  • 822
  • 02 Dec 2021
Topic Review
Annona cherimola Mill.
Annona cherimola Mill., or the custard apple, is one of the species belonging to the Annonaceae family, is widely used in traditional medicine, and has been reported to be a valuable source of bioactive compounds.
  • 811
  • 18 Jun 2021
Topic Review
Medical Applications of Metallic Bismuth Nanoparticles
In the diagnostic field, preclinical proofs of concept have been demonstrated for X-ray, photoacoustic and fluorescence imaging. In the therapeutic field, several preclinical studies have shown the potential of bismuth nanoparticles as X-ray radiosensitizers for use in radiotherapy and as photothermal agents for applications in near infrared phototherapy.
  • 807
  • 10 Nov 2021
Topic Review
Extraction Techniques of Procyanidins
Procyanidins are an important group of bioactive molecules known for their benefits to human health. These compounds are promising in the treatment of chronic metabolic diseases such as cancer, diabetes, and cardiovascular disease, as they prevent cell damage related to oxidative stress.
  • 804
  • 04 Jan 2022
Topic Review
Antimicrobial Resistance and Inorganic Nanoparticles
A bacterium becomes resistant due to the transfer of genes encoding antibiotic resistance. Bacteria constantly mutate; therefore, their defense mechanisms change constantly.  Nanotechnology plays a key role in antimicrobial resistance due to materials modified at the nanometer scale, allowing large numbers of molecules to assemble to have a dynamic interface. These nanomaterials act as carriers, and their design is mainly focused on introducing the temporal and spatial release of the payload of antibiotics. In addition, they generate new antimicrobial modalities for the bacteria, which are not capable of protecting themselves.
  • 801
  • 18 Dec 2021
Topic Review
Alpha-Ketoglutarate and 5-HMF
Clinical and pre-clinical studies of an anti-tumoral solution containing aKG, 5-HMF, N-acetyl-selenomethionine, and N-acetylmethionine for treating tumors showed, on one hand, good therapeutic efficacy during infusion therapy in prostate cancer patients by increasing the PSA doubling time; on the other hand, a reduction of tumoral mass was shown in lung cancer patients.
  • 794
  • 19 Nov 2021
Topic Review
Synthesis of Functional Geopolymeric Hybrid Materials
New synthetic hybrid materials, with an inorganic and organic nature, have been developed to promote their application as protective coatings and/or structural consolidants for several substrates in the construction industry and cultural heritage field. In this background, the scientific community paid attention to geopolymers and their new hybrid functional derivatives to design and develop innovative and sustainable composites with better chemical resistance, durability and mechanical characteristics. 
  • 793
  • 14 Mar 2022
Topic Review
Cutaneous Flavonoid Delivery System
Flavonoids are one of the vital classes of natural polyphenolic compounds abundantly found in plants. Due to their wide range of therapeutic properties, which include antioxidant, anti-inflammatory, photoprotective, and depigmentation effects, flavonoids have been demonstrated to be promising agents in the treatment of several skin disorders. However, their lipophilic nature and poor water solubility invariably lead to limited oral bioavailability. In addition, they are rapidly degraded and metabolized in the human body, hindering their potential contribution to the prevention and treatment of many disorders. Thus, to overcome these challenges, several cutaneous delivery systems have been extensively studied. Topical drug delivery besides offering an alternative administration route also ensures a sustained release of the active compound at the desired site of action. Incorporation into lipid or polymer-based nanoparticles appears to be a highly effective approach for cutaneous delivery of flavonoids with good encapsulation potential and reduced toxicity.
  • 791
  • 22 Apr 2022
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