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Topic Review
Activity of Kalanchoe pinnata in Cancer
Kalanchoe pinnata (Lam) Pers. (syn. Bryophyllum pinnatum Lam.), belonging to the genus Kalanchoe, is a succulent plant cultivated in gardens, which can be found as a herb or shrub. The bioactive ingredients in Kalanchoe pinnata, a succulent herb with ethnomedical applications for several diseases, including cancer, and reveal its anticancer mechanisms through a molecular approach.
  • 7.1K
  • 17 Oct 2022
Topic Review
Aquaporin Inhibitors
Aquaporins (AQPs) are water channel proteins that are essential to life, being expressed in all kingdoms. In humans, there are 13 AQPs, at least one of which is found in every organ system. The structural biology of the AQP family is well-established and many functions for AQPs have been reported in health and disease. AQP expression is linked to numerous pathologies including tumor metastasis, fluid dysregulation, and traumatic injury. The targeted modulation of AQPs therefore presents an opportunity to develop novel treatments for diverse conditions. Various techniques such as video microscopy, light scattering and fluorescence quenching have been used to test putative AQP inhibitors in both AQP-expressing mammalian cells and heterologous expression systems. The inherent variability within these methods has caused discrepancy and many molecules that are inhibitory in one experimental system (such as tetraethylammonium, acetazolamide, and anti-epileptic drugs) have no activity in others. Some heavy metal ions (that would not be suitable for therapeutic use) and the compound, TGN-020, have been shown to inhibit some AQPs. Clinical trials for neuromyelitis optica treatments using anti-AQP4 IgG are in progress. However, these antibodies have no effect on water transport. More research to standardize high-throughput assays is required to identify AQP modulators for which there is an urgent and unmet clinical need.
  • 6.9K
  • 06 Sep 2021
Topic Review
Molecular Mechanisms of Homologous Recombination
Homologous recombination (HR) is a fundamental evolutionarily conserved process that plays prime role(s) in genome stability maintenance through DNA repair and through the protection and resumption of arrested replication forks. HR promotes the exchange between homologous DNA sequences resulting in a novel combination of the genetic material. Therefore, HR is essential in genome stability maintenance but also plays an important role in genome diversity; such as in the case of meiosis. Many HR genes are deregulated in cancer cells. Notably, the breast cancer genes BRCA1 and BRCA2, two important HR players, are the most frequently mutated genes in familial breast and ovarian cancer. 
  • 6.9K
  • 28 Apr 2021
Topic Review
Sesquiterpene Lactones
Sesquiterpene lactones, a vast group of terpenoids isolated from Asteraceae family species, exhibit a wide variety of biological activities and several of them are already available on the medicines market, such as artemisinin. Here are presented and discussed the most recent and impactful results in vivo, preclinical and clinical studies, involving a selection of ten sesquiterpene lactones (alantolactone, arglabin, costunolide, cynaropicrin, helenalin, inuviscolide, lactucin, parthenolide, thapsigargin and tomentosin) and some of their derivatives.
  • 6.4K
  • 28 Oct 2020
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). 
  • 6.3K
  • 20 May 2022
Topic Review
G-Protein-Coupled Receptors
G-protein-coupled receptors (GPCRs), which make up the largest superfamily of human membrane proteins, play pivotal roles in mediating intracellular signaling and inducing cell proliferation, cell growth, and cell motility through the association and subsequent dissociation of G-proteins in response to external stimuli.
  • 6.0K
  • 05 Feb 2021
Topic Review Peer Reviewed
Serum Albumin
Being one of the most abundant proteins in human and other mammals, albumin plays a crucial role in transporting various endogenous and exogenous molecules and maintaining of colloid osmotic pressure of the blood. It is not only the passive but also the active participant of the pharmacokinetic and toxicokinetic processes possessing a number of enzymatic activities. A free thiol group of the albumin molecule determines the participation of the protein in redox reactions. Its activity is not limited to interaction with other molecules entering the blood: of great physiological importance is its interaction with the cells of blood, blood vessels and also outside the vascular bed. This topic review contains data on the enzymatic, inflammatory and antioxidant properties of serum albumin. 
  • 6.0K
  • 13 Apr 2022
Topic Review
Thermodynamic Dissipation Theory of Life
The Thermodynamic Dissipation Theory of the Origin and Evolution of Life argues that the escence of the origin of life was the microscopic dissipative structuring under UVC light of organic pigments (now known as the fundamental molecules of life - those common to all three domains) and their proliferation over the entire Earth surface, driven by the thermodynamic imperative of dissipating this part of the Archean solar spectrum into heat. With time, dissipative structuring led to ever more complex biosynthetic pathways for creating pigments and their support structures (and processes) which could dissipate not only the UVC region but also other UV regions and the visible wavelengths, until today reaching the "red edge" (at approximately 700 nm). The heat of dissipation of photons absorbed on organic pigments in water then catalyzes a host of coupled secondary dissipative processes such as; the water cycle, ocean and wind currents, hurricanes, etc. pushing the limit for dissipation of the incident light even further towards the infrared. The thermodynamic dissipation theory thus assgins an explicit thermodynamic function to life; the dissipative structuring, proliferation, and evolution of molecular pigments and their complexes from common precursor carbon based molecules under the impressed short wavelength solar photon potential to perform the explicit thermodynamic function of dissipating this light into long wavelength infrared light (heat). In a general sense, the origin of life is no different than the origin of other dissipative structuring processes like hurricanes and the water cycle, except that these latter processes deal with structuring involving hydrogen bonding while life deals with structuring involving covalent bonding. The external photon potential supplied continuously by the environment (our Sun), and its dissipation into heat by the assembly of dissipative structures, are, therefore, both integral components necessary for understanding life. Difficult problems related to the origin of life, such as enzyme-less replication of RNA and DNA, homochirality of the fundamental molecules, and the origin of amino acid -codon assignments (information encoding in RNA and DNA), also find simple explanations within this same dissipative thermodynamic framework once the existence of a relation between primordial RNA and DNA replication and UV-C photon dissipation is established.
  • 5.9K
  • 04 Feb 2021
Topic Review
Wood Formation in Plants
Unlike herbaceous plants, woody plants undergo volumetric growth (a.k.a. secondary growth) through wood formation, during which the secondary xylem (i.e., wood) differentiates from the vascular cambium. Wood is the most abundant biomass on Earth and, by absorbing atmospheric carbon dioxide, functions as one of the largest carbon sinks. As a sustainable and eco-friendly energy source, lignocellulosic biomass can help address environmental pollution and the global climate crisis.
  • 5.9K
  • 15 Jul 2022
Topic Review
Disse (Space of Disse)
Space of Disse: a thin perisinusoidal area between the endothelial cells and hepatocytes filled with blood plasma, nutrients and oxygen, but also debris from our organism, that have acquired great importance in liver disease
  • 5.8K
  • 20 Feb 2021
Topic Review
L-Carnitine in Mitochondria
Mitochondria control cellular fate by various mechanisms and are key drivers of cellular metabolism. Although the main function of mitochondria is energy production, they are also involved in cellular detoxification, cellular stabilization, as well as control of ketogenesis and glucogenesis. Conditions like neurodegenerative disease, insulin resistance, endocrine imbalances, liver and kidney disease are intimately linked to metabolic disorders or inflexibility and to mitochondrial dysfunction. Mitochondrial dysfunction due to a relative lack of micronutrients and substrates is implicated in the development of many chronic diseases. l-carnitine is a vital molecule that is found in all living cells. It is a quaternary amine (3-hydroxy-4-N-trimethylaminobutyrate) whose main function in mammalian cells is the transfer of long chain fatty acids across the inner mitochondrial membrane for β- oxidation and generation of ATP energy. 
  • 5.7K
  • 11 Mar 2022
Topic Review
Role of Granulosa and Theca Cells in PCOS
Polycystic ovary syndrome (PCOS) is the most common heterogeneous endocrine disorder among women of reproductive age. The pathogenesis of PCOS remains elusive and there is evidence suggesting the potential contribution of genetic interactions or predispositions combined with environmental factors.
  • 5.5K
  • 16 Jan 2023
Topic Review
Food Wastes as Packaging Materials
Packaging materials have to allow controlled respiration, maintain polymer structure against mechanical damage, prevent microbiological and chemical spoilage of food, and act as a selective gas and water vapor barrier. The most widely used materials in the food packaging industry are glass, plastics, metals, and paper. As mechanical properties of materials are important for food protection, mostly flexible and rigid synthetic packaging materials are preferred.
  • 5.4K
  • 19 Aug 2021
Topic Review
Protein Quality Control (PQC)
Eukaryotic cells have a well-organized, tightly regulated protein quality control (PQC) system. This quality control system includes the molecular chaperones, ubiquitin/proteasome-dependent protein degradation, and autophagy machinery (target and uptake of non-native conformer in the spatial compartments) that consistently monitors and maintains the conformational state of cellular proteins.
  • 5.4K
  • 18 Mar 2021
Topic Review
Phosphoribosyl Pyrophosphate Synthetase
Phosphoribosyl pyrophosphate synthetase (PRS EC 2.7.6.1) is a rate-limiting enzyme that irreversibly catalyzes the formation of phosphoribosyl pyrophosphate (PRPP) from ribose-5-phosphate and adenosine triphosphate (ATP). This key metabolite is required for the synthesis of purine and pyrimidine nucleotides, the two aromatic amino acids histidine and tryptophan, the cofactors nicotinamide adenine dinucleotide (NAD+) and nicotinamide adenine dinucleotide phosphate (NADP+), all of which are essential for various life processes. Despite its ubiquity and essential nature across the plant and animal kingdoms, PRPP synthetase displays species-specific characteristics regarding the number of gene copies and architecture permitting interaction with other areas of cellular metabolism. The impact of mutated PRS genes in the model eukaryote Saccharomyces cerevisiae on cell signalling and metabolism may be relevant to the human neuropathies associated with PRPS mutations. Human PRPS1 and PRPS2 gene products are implicated in drug resistance associated with recurrent acute lymphoblastic leukaemia and progression of colorectal cancer and hepatocellular carcinoma.
  • 5.3K
  • 02 Aug 2022
Topic Review
Classes of Transposable Elements
Transposable elements (TEs) are mobile genetic elements that constitute a sizeable portion of many eukaryotic genomes. Through their mobility, they represent a major source of genetic variation, and their activation can cause genetic instability and has been linked to aging, cancer and neurodegenerative diseases.
  • 5.3K
  • 23 Sep 2022
Topic Review
CRISPR-Cas Genome Editing Components in C. elegans
CRISPR-Cas allows us to introduce desired genome editing, including mutations, epitopes, and deletions, with unprecedented efficiency. The development of CRISPR-Cas has progressed to such an extent that it is now applicable in various fields, with the help of model organisms. C. elegans is one of the pioneering animals in which numerous CRISPR-Cas strategies have been rapidly established. Ironically, the emergence of numerous methods makes the choice of the correct method difficult. Choosing an appropriate selection or screening approach is the first step in planning a genome modification.
  • 5.2K
  • 30 Dec 2022
Topic Review
Matrix Metalloproteinases and Their Inhibitors
Matrix metalloproteinases (MMPs) are a family of zinc-dependent extracellular matrix (ECM) remodeling endopeptidases that have the capacity to degrade almost every component of the ECM. The degradation of the ECM is of great importance, since it is related to embryonic development and angiogenesis. It is also involved in cell repair and the remodeling of tissues. When the expression of MMPs is altered, it can generate the abnormal degradation of the ECM. This is the initial cause of the development of chronic degenerative diseases and vascular complications generated by diabetes. In addition, this process has an association with neurodegeneration and cancer progression. Within the ECM, the tissue inhibitors of MMPs (TIMPs) inhibit the proteolytic activity of MMPs. TIMPs are important regulators of ECM turnover, tissue remodeling, and cellular behavior. Therefore, TIMPs (similar to MMPs) modulate angiogenesis, cell proliferation, and apoptosis. An interruption in the balance between MMPs and TIMPs has been implicated in the pathophysiology and progression of several diseases.
  • 5.2K
  • 18 Sep 2021
Topic Review
Fatty Acid Synthase
Fatty acid synthase is a multi-enzyme protein that involves in fatty acid synthesis. It's main function is to synthesise palmitate, a 16-carbon long chain saturated fatty acid from acetyl-CoA and malonyl-CoA, in the presence of NADPH.
  • 5.2K
  • 01 Sep 2020
Topic Review
Non-Enzymatic Antioxidants
Oxidative stress has long been considered one of the pathophysiological mechanisms involved in numerous diseases, which has led to the investigation of the antioxidant systems as a promising therapy more than two decades ago. A useful antioxidant must meet specific characteristics; it must be capable of interacting with biologically relevant oxidants and free radicals; its reaction by-products should be harmless; and finally, it must reach a sufficiently high concentration in the tissue and cell compartments to ensure its activity is quantitatively relevant.
  • 5.2K
  • 24 May 2022
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