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Topic Review
The Spemann Organizer
In 1924, to understand the processes involved in developmental biology, Spemann and Mangold transplanted a blastopore lip between different ectodermal regions of amphibian embryos. The transplanted dorsal tissue differentiated mostly into a notochord, while the ectoderm of the host dorsal tissue that was sitting above the transplanted region (blastopore lip) was induced and differentiated to form a Siamese twin containing dorsal tissues such as somites and a neural plate, which would form the central nervous system, forming the bulk of a second axis. The major findings were that the transplant had altered the fate of the overlying cells and that the neural folds were built from recipient cells and not donor cells. Spemann and Mangold discovered the organizing center in the dorsal blastopore lip of amphibians. This center consists of a cluster of cells in the developing embryo that have the ability to interact and instruct morphogenesis in the surrounding cells during gastrulation. When transplanted to the ventral side of the embryo, the center will induce the formation of a secondary axis, promoting the development of the central nervous system, organs, and tissues, as well as the formation of the main body axis. Spemann and Mangold found the first evidence of the organizing center, thereafter called the “Spemann organizer”, and its major role in the development of vertebrates. This discovery also introduced the concept of induction in embryonic development, which refers to the method used by specific cells to affect the fate of other embryonic cells. A major milestone had been achieved for developmental biology.
  • 2.7K
  • 11 Nov 2021
Topic Review
Process of Apoptosis
The term “Apoptosis” originates from Greek, which means the shedding of leaves from trees in autumn or the falling of petals from flowers. Apoptosis was firstly utilized by Kerr, Wyllie, and Currie in 1972 for explaining a morphologically discrete way of cell death. However, multiple concepts of apoptosis were precisely explained several years back. The main concept of apoptosis emerged from the knowledge of the process of programmed cell death that takes place in the developmental cycle of Caenorhabditis elegans.
  • 2.6K
  • 05 May 2022
Topic Review
Melatonin: ATP Regulation in MLOs
Biomolecular condensates are membraneless organelles (MLOs) that form dynamic, chemically distinct subcellular compartments organizing macromolecules such as proteins, RNA, and DNA in unicellular prokaryotic bacteria and complex eukaryotic cells. Separated from surrounding environments, MLOs in the nucleoplasm, cytoplasm, and mitochondria assemble by liquid–liquid phase separation (LLPS) into transient, non-static, liquid-like droplets that regulate essential molecular functions. LLPS is primarily controlled by ATP-dependent post-translational modifications (PTMs) that fine-tune the balance between attractive and repulsive charge states and/or binding motifs of proteins. Aberrant phase separation due to the absence of adequate hydrotropic small molecules such as ATP can cause pathological protein aggregation in diseases such as neurodegenerative disorders. Melatonin is a potent antioxidant capable of protecting cardiolipin and membrane lipids raft domains from peroxidation to support ATPase functionality and ion channel activities that may exert a dominant influence over phase separation in biomolecular condensates during condensate coacervation or dissolution processes that are ATP-dependent. 
  • 2.6K
  • 30 Sep 2021
Topic Review
Technical Lignin
Lignin, the term commonly used in literature, represents a group of heterogeneous aromatic compounds of plant origin. 
  • 2.6K
  • 16 Feb 2021
Topic Review
Rheumatoid Arthritis
Rheumatoid arthritis (RA) is a chronic autoimmune disease affecting the joints. It is characterized by a progressive symmetric inflammation of affected joints resulting in cartilage destruction, bone erosion, and disability. In rheumatoid arthritis (RA) chronic autoimmune responses result in destruction of joints in affected patients. 
  • 2.6K
  • 01 Nov 2020
Topic Review
Immunopeptidome
Major histocompatibility complex class I (MHC I) plays a crucial role in the development of adaptive immune response in vertebrates. MHC molecules are cell surface protein complexes loaded with short peptides and recognized by the T-cell receptors (TCR). Peptides associated with MHC are named immunopeptidome. The MHC I immunopeptidome is produced by the proteasome degradation of intracellular proteins. The knowledge of the immunopeptidome repertoire facilitates the creation of personalized antitumor or antiviral vaccines. A huge number of publications on the immunopeptidome diversity of different human and mouse biological samples - plasma, peripheral blood mononuclear cells (PBMCs), and solid tissues, including tumors - appeared in the scientific journals in the last decade. Significant immunopeptidome identification efficiency was achieved by advances in technology: the immunoprecipitation of MHC and mass spectrometry-based approaches.
  • 2.6K
  • 30 Nov 2020
Topic Review
Luminogens with Aggregation-Induced Emission
Luminogens with aggregation-induced emission (AIEgens) have been widely applied in the field of photodynamic therapy. Among them, aggregation-induced emission photosensitizers (AIE–PSs) are demonstrated with high capability in fluorescence and photoacoustic bimodal imaging, as well as in fluorescence imaging-guided photodynamic therapy. They not only improve diagnosis accuracy but also provide an efficient theranostic platform to accelerate preclinical translation as well.
  • 2.5K
  • 21 Jan 2021
Topic Review
DPPH Radical Scavenging Assay
The 1,1-diphenyl-2-picrylhydrazil (DPPH) radical removal is one of the most widely applied and used methods in food and pharmaceutical applications. DPPH method gives a better response for mostly phenolic compounds and then for compounds with limited polarity. In the case of polar and phenolic compounds, adding water to the reaction medium, that is, aqueous methanol, gives better results. When testing low-polarity compounds, ethyl acetate with a radical is suitable. DPPH reaction rates depend on the steric accessibility of the radical site rather than the chemical properties of the tested antioxidant compounds. The rate at which DPPH reacts with antioxidants depends on the varying ratios of mixed single-electron transfer (SET) and hydrogen atom transfer (HAT) mechanisms. The reaction mechanisms of DPPH∙ scavenging and responses are modified by many environmental and experimental factors.
  • 2.5K
  • 08 Sep 2023
Topic Review
N-Acetylcysteine
Exercise frequently alters the metabolic processes of oxidative metabolism in athletes, including exposure to extreme reactive oxygen species impairing exercise performance. Therefore, both researchers and athletes have been consistently investigating the possible strategies to improve metabolic adaptations to exercise-induced oxidative stress. N-acetylcysteine (NAC) has been applied as a therapeutic agent in treating many diseases in humans due to its precursory role in the production of hepatic glutathione, a natural antioxidant.
  • 2.5K
  • 03 Feb 2021
Topic Review
Hyaluronic Acid in Cosmeceuticals
Hyaluronic acid (HA) is a polysaccharide belonging to the glycosaminoglycans, made up of disaccharide units constituted of N-acetylglucosamine and D-glucuronic acid.
  • 2.5K
  • 29 Jul 2021
Topic Review
Benfotiamine
Benfotiamine (BFT) has antioxidant and anti-inflammatory properties that seem to be mediated by a mechanism independent of the coenzyme function of ThDP. BFT has no adverse effects and improves cognitive outcome in patients with mild Alzheimer’s disease (AD). 
  • 2.5K
  • 04 Jun 2021
Topic Review
Vitamin D Metabolism Gene Polymorphisms
Vitamin D is a potent immunonutrient that through its main metabolite calcitriol, regulates the immunomodulation of macrophages, dendritic cells, T and B lymphocytes, which express the vitamin D receptor (VDR), and they produce and respond to calcitriol. Genetic association studies have shown that up to 65% of vitamin D serum variance may be explained due to genetic background. 
  • 2.4K
  • 01 Jan 2022
Topic Review
Coenzyme A
Coenzyme A (CoA) is synthetized from pantothenic acid (commonly known as vitamin B5). The importance of CoA as a carrier of acyl residues in cell metabolism is well understood. Coenzyme A participates in more than 100 different catabolic and anabolic reactions, including those involved in the metabolism of lipids, carbohydrates, proteins, ethanol, bile acids, and xenobiotics.
  • 2.4K
  • 15 Dec 2020
Topic Review
The Oncogenic Potential of SARS-CoV-2
Some viruses are known to be associated with the onset of specific cancers. Seven of these microorganisms, recognized as oncogenic viruses or oncoviruses, promote tumorigenesis in humans, converting normal cells into cancer cells through the modulation of central metabolic pathways or the impairment of genomic integrity mechanisms, consequently inhibiting the apoptotic machinery and/or enhancing cell proliferation. Actually, research indicates that SARS-CoV-2 infection and COVID-19 progression may predispose recovered patients to cancer onset and accelerate cancer development. This hypothesis is based on the growing evidence regarding the ability of SARS-CoV-2 to modulate oncogenic pathways, promoting chronic low-grade inflammation and causing tissue damage. As for SARS-CoV-2, its role as an oncogenic virus seems to occur through the inhibition of oncosuppressors or controlling the metabolic and autophagy pathways in the infected cells. On the other hand, looking at the SARS-CoV-2─cancer relationship from an opposite perspective, oncolytic effects and anti-tumor immune response were triggered by SARS-CoV-2 infection in some cases.
  • 2.4K
  • 11 May 2023
Topic Review
Phospholipase A1
Phospholipase A1 (PLA1) is an enzyme that cleaves an ester bond at the sn-1 position of glycerophospholipids, producing a free fatty acid and a lysophospholipid.
  • 2.4K
  • 27 Apr 2022
Topic Review
Cutibacterium acnes
Cutibacterium acnes is a member of the skin microbiota found predominantly in regions rich in sebaceous glands. It is involved in maintaining healthy skin and has long been considered a commensal bacterium. Its involvement in various infections has led to its emergence as an opportunist pathogen. Interactions between C. acnes and the human host, including the human skin microbiota, promote the selection of C. acnes strains capable of producing several virulence factors that increase inflammatory capability. This pathogenic property may be related to many infectious mechanisms, such as an ability to form biofilms and the expression of putative virulence factors capable of triggering host immune responses or enabling C. acnes to adapt to its environment. During the past decade, many studies have identified and characterized several putative virulence factors potentially involved in the pathogenicity of this bacterium. These virulence factors are involved in bacterial attachment to target cells, polysaccharide-based biofilm synthesis, molecular structures mediating inflammation, and the enzymatic degradation of host tissues. C. acnes, like other skin-associated bacteria, can colonize various ecological niches other than skin. It produces several proteins or glycoproteins that could be considered to be active virulence factors, enabling the bacterium to adapt to the lipophilic environment of the pilosebaceous unit of the skin, but also to the various organs it colonizes. 
  • 2.4K
  • 22 Sep 2021
Topic Review
Membrane Protein
Membrane proteins are polypeptides integrated into or associated with biological membranes. They are present at roughly equal weight to phospholipids in plasma membranes of cells, in outer membranes of bacteria, mitochondria, chloroplasts and in other organelles. Membrane proteins govern the active functions of membranes, such as transport, signalling, asymmetry and polarisation. Membrane proteins follow characteristic folding patterns and have hydrophobic domains that make them compatible with the amphipathic lipid biayers.
  • 2.4K
  • 24 Dec 2020
Topic Review
Light, Water, and Melatonin Relationship with Hydrogen Bonds
The synergistic relationship between melatonin, water, and light may have originated billions of years ago when primitive unicellular organisms depended on this effective and precise synergy to modulate phase separation to control protein aggregation and associated biological effects. The efficacy of this synergy also provides a credible explanation for the immensely successful and rapid distribution of melatonin via horizontal gene transfer. The discovery of the serotonin N-acetyltransferase (SNAT) gene responsible for the synthesis of essential melatonin substrate N-acetylserotonin (NAS) in archaea firmly establishes the quintessential role played by melatonin in early primitive organisms that use phase separation as the fundamental driver for relevant biochemical and biophysical processes to support metabolism, replication, and survival.
  • 2.4K
  • 27 Mar 2023
Topic Review
Reactive Oxygen Species
Reactive oxygen species (ROS) can directly activate HSCs or induce inflammation or programmed cell death, especially pyroptosis, in hepatocytes, which in turn activates HSCs and fibroblasts to produce ECM proteins.
  • 2.3K
  • 27 Jan 2022
Topic Review
siRNA Structure, Function and Delivery
siRNA is a double-stranded RNA molecule with 21- and 22-nucleotide generated by ribonuclease III cleavage from longer double-stranded RNA (dsRNAs). After binding to the RNA-induced silencing complex (RISC) in the cytoplasm, the sense strand of siRNA undergoes ejection, while the antisense strand of siRNA targets the complementary messenger RNA (mRNA). 
  • 2.3K
  • 20 May 2022
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