Your browser does not fully support modern features. Please upgrade for a smoother experience.
Subject:
All Disciplines Arts & Humanities Biology & Life Sciences Business & Economics Chemistry & Materials Science Computer Science & Mathematics Engineering Environmental & Earth Sciences Medicine & Pharmacology Physical Sciences Public Health & Healthcare Social Sciences
Sort by:
Most Viewed Latest Alphabetical (A-Z) Alphabetical (Z-A)
Filter:
All Topic Review Biography Peer Reviewed Entry Video Entry
Topic Review
Matrix Metallopeptidase
Matrix metallopeptidases (MMPs), also known as matrix metalloproteinases or matrixins, are metalloproteinases that are calcium-dependent zinc-containing endopeptidases; other family members are adamalysins, serralysins, and astacins. The MMPs belong to a larger family of proteases known as the metzincin superfamily. Collectively, these enzymes are capable of degrading all kinds of extracellular matrix proteins, but also can process a number of bioactive molecules. They are known to be involved in the cleavage of cell surface receptors, the release of apoptotic ligands (such as the FAS ligand), and chemokine/cytokine inactivation. MMPs are also thought to play a major role in cell behaviors such as cell proliferation, migration (adhesion/dispersion), differentiation, angiogenesis, apoptosis, and host defense. They were first described in vertebrates (1962), including humans, but have since been found in invertebrates and plants. They are distinguished from other endopeptidases by their dependence on metal ions as cofactors, their ability to degrade extracellular matrix, and their specific evolutionary DNA sequence. Recently matrix metalloproteinases have been proposed as markers of many pathological conditions for their ability to degrade extracellular matrix components and remodel tissues. Herein, MMPs have been reported as one of the main factors of cancer progression and metastasis formation. This led to the emerging research field in biosensors development for the detection of such enzymes.
  • 1.2K
  • 23 Nov 2022
Topic Review
Mitochondrial Volume Regulation and Swelling Mechanisms in Cardiomyocytes
Mitochondrion, known as the “powerhouse” of the cell, regulates ion homeostasis, redox state, cell proliferation and differentiation, and lipid synthesis. The inner mitochondrial membrane (IMM) controls mitochondrial metabolism and function. It possesses high levels of proteins that account for ~70% of the membrane mass and are involved in the electron transport chain, oxidative phosphorylation, energy transfer, and ion transport, among others. The mitochondrial matrix volume plays a crucial role in IMM remodeling. Several ion transport mechanisms, particularly K+ and Ca2+, regulate matrix volume. Small increases in matrix volume through IMM alterations can activate mitochondrial respiration, whereas excessive swelling can impair the IMM topology and initiates mitochondria-mediated cell death. The opening of mitochondrial permeability transition pores, the well-characterized phenomenon with unknown molecular identity, in low- and high-conductance modes are involved in physiological and pathological increases of matrix volume.
  • 1.2K
  • 10 Aug 2023
Topic Review
Presynaptic Precursor Vesicle Biogenesis
The faithful formation and, consequently, function of a synapse requires continuous and tightly controlled delivery of synaptic material. At the presynapse, a variety of proteins with unequal molecular properties are indispensable to compose and control the molecular machinery concerting neurotransmitter release through synaptic vesicle fusion with the presynaptic membrane. As presynaptic proteins are produced mainly in the neuronal soma, they are obliged to traffic along microtubules through the axon to reach the consuming presynapse. 
  • 1.2K
  • 09 Oct 2023
Topic Review
Inflammaging of Hematopoietic Stem Cells
Hematopoietic stem cells (HSCs) sustain the lifelong production of all blood cell lineages. The functioning of aged HSCs is impaired, including a declined repopulation capacity and myeloid and platelet-restricted differentiation. Both cell-intrinsic and microenvironmental extrinsic factors contribute to HSC aging. Recent studies highlight the emerging role of inflammation in contributing to HSC aging. 
  • 1.2K
  • 13 Sep 2021
Topic Review
Phenotypical and Functional Polymorphism of Liver Resident Macrophages
Liver diseases are one of the main causes of mortality. In this regard, the development of new ways of reparative processes stimulation is relevant. Macrophages play a leading role in the regulation of liver homeostasis in physiological conditions and in pathology. In this regard, the development of new liver treatment methods is impossible without taking into account this cell population. Resident macrophages of the liver, Kupffer cells, represent a unique cell population, first of all, due to their development. Most of the liver macrophages belong to the self-sustaining macrophage cell population, whose origin is not bone marrow. In addition, Kupffer cells are involved in such processes as regulation of hepatocyte proliferation and apoptosis, remodeling of the intercellular matrix, lipid metabolism, protective function, etc. Such a broad spectrum of liver macrophage functions indicates their high functional plasticity. The Recent data on the development, phenotypic and functional plasticity, and participation in the reparative processes of liver macrophages: resident macrophages (Kupffer cells) and bone marrow-derived macrophages were summarized.
  • 1.2K
  • 29 Jan 2022
Topic Review
Cancer Spheroids and Organoids
Spheroids and organoids are important novel players in medical and life science research. They are gradually replacing two-dimensional (2D) cell cultures. Indeed, three-dimensional (3D) cultures are closer to the in vivo reality and open promising perspectives for academic research, drug screening, and personalized medicine. A large variety of cells and tissues, including tumor cells, can be the starting material for the generation of 3D cultures, including primary tissues, stem cells, or cell lines.
  • 1.2K
  • 18 Apr 2023
Topic Review
Two Faces of Vitamin C: AA vs. DHA
Historically, vitamin C has been associated with many regulatory processes that involve specific signaling pathways. Among the most studied signaling pathways are those involved in the regulation of aging, differentiation, neurotransmission, proliferation, and cell death processes in cancer. This wide variety of regulatory effects is due to the fact that vitamin C has a dual mechanism of action. The reduced form of vitamin C (ascorbic acid, AA) is an essential micronutrient of small size; it is soluble in water and has two dissociable protons with pKa values of 4.2 and 11.8. At physiological pH, its reduced form predominates as the monovalent ascorbate anion (AA); when it loses the second proton, it is oxidized to dehydroascorbic acid (DHA).
  • 1.2K
  • 14 Jun 2022
Topic Review
Exosomes in Alpha-Synucleinopathies
The pathological accumulation of alpha-synuclein governs the pathogenesis of neurodegenerative disorders, such as Parkinson’s disease, dementia with Lewy bodies, and multiple system atrophy, collectively termed alpha-synucleinopathies. Alpha-synuclein can be released in the extracellular space, partly via exosomes, and this extracellular protein pool may contribute to disease progression by facilitating the spread of pathological alpha-synuclein or activating immune cells. The content of exosomes depends on their origin and includes specific proteins, lipids, functional mRNAs and various non-coding RNAs. Given their ability to mediate intercellular communication via the transport of multilevel information, exosomes are considered to be transporters of toxic agents. Beyond neurons, glial cells also release exosomes, which may contain inflammatory molecules and this glia-to-neuron or neuron-to-glia transmission of exosomal alpha-synuclein may contribute to the propagation of pathology and neuroinflammation throughout the brain. In addition, as their content varies as per their originating and recipient cells, these vesicles can be utilized as a diagnostic biomarker for early disease detection, whereas targeted exosomes may be used as scaffolds to deliver therapeutic agents into the brain.
  • 1.2K
  • 21 Jul 2022
Topic Review
Mesenchymal Stem Cell Secretome
The use of mesenchymal stem cells (MSC) for the treatment of cutaneous wounds is currently of enormous interest. However, the broad translation of cell therapies into clinical use is hampered by their efficacy, safety, manufacturing and cost. MSCs release a broad repertoire of trophic factors and immunomodulatory cytokines, referred to as the MSC secretome, that has considerable potential for the treatment of cutaneous wounds as a cell-free therapy. In this review, we outline the current status of MSCs as a treatment for cutaneous wounds and introduce the potential of the MSC secretome as a cell-free alternative for wound repair. We discuss the challenges and provide insights and perspectives for the future development of the MSC secretome as well as identify its potential clinical translation into a therapeutic treatment.
  • 1.2K
  • 21 Oct 2020
Topic Review
3C Protease as Ferroptosis Inducer
Regulated cell death (RCD) is a fundamental process common to nearly all living beings and essential for the development and tissue homeostasis in animals and humans. A wide range of molecules can induce RCD including a number of viral proteolytic enzymes. To date, numerous data indicate that picornaviral 3C proteases can induce RCD. In most reported cases, these proteases induce classical caspase-dependent apoptosis. In contrast, the human hepatitis A virus 3C protease (3Cpro) has recently been shown to cause caspase-independent cell death accompanied by previously undescribed features. In the current topic the results of the study where 3Cpro-induced cell death was characterized morphologically and biochemically are presented. It was found that dead cells demonstrated necrosis-like morphological changes including permeabilization of plasma membrane, loss of mitochondrial potential, as well as mitochondria and nuclei swelling. Additionally, it was shown that 3Cpro-induced cell death was efficiently blocked by ferroptosis inhibitors and was accompanied by intense lipid peroxidation. Taken together, these results indicate that 3Cpro induces ferroptosis upon its individual expression in human cells. This is the first demonstration that a proteolytic enzyme can induce ferroptosis, the recently discovered and actively studied type of RCD.
  • 1.2K
  • 22 Sep 2021
Topic Review
ARHGAP11B
ARHGAP11B is a human-specific gene that likely played a crucial role in human neocortex evolution by inducing hallmarks of cortical expansion. In contrast to its ancestral paralog, ARHGAP11A, ARHGAP11B does not act as a Rho GTPase Activating Protein in the nucleus but is localized in mitochondria and increases glutaminolysis. This increase is a prerequisite for increased basal progenitor proliferation – one essential basis for cortical expansion.
  • 1.2K
  • 28 May 2021
Topic Review
Somatic Polyploidy
Somatic polyploidy was found in the tissues of all multicellular organisms (including algae, mosses, lichens, vascular plants, invertebrates, and vertebrates), which points to its adaptive value. In human and warm-blooded animals, polyploidy can be a part of normal postnatal morphogenetic programs and can be a manifestation of response to pathological stimuli and diseases.
  • 1.2K
  • 11 Apr 2022
Topic Review
Diagnosis of Hepatocellular Carcinoma
There are several risk factors of HCC such as viral hepatitis (B, C), cirrhosis, tobacco and alcohol use, aflatoxin-contaminated food, pesticides, diabetes, obesity, nonalcoholic fatty liver disease (NAFLD), and metabolic and genetic diseases. Diagnosis of HCC is based on different methods such as imaging ultrasonography (US), multiphasic enhanced computed tomography (CT), magnetic resonance imaging (MRI), and several diagnostic biomarkers.
  • 1.2K
  • 17 Jul 2023
Topic Review
Yeast Cell Polarity
A bottom-up route towards predicting evolution relies on a deep understanding of the complex network that proteins form inside cells. In a rapidly expanding panorama of experimental possibilities, the most difficult question is how to conceptually approach the disentangling of such complex networks. These can exhibit varying degrees of hierarchy and modularity, which obfuscate protein functions that may prove pivotal for adaptation. Using the well-established polarity network in budding yeast as a case study, we organize current literature to highlight protein entrenchments inside polarity in five sub modules: timing, mating, bud-scar, reaction-diffusion and the actin pathway. 
  • 1.2K
  • 07 Dec 2020
Topic Review
Methionine and Stemness
Stem cells are a population of undifferentiated cells with self-renewal and differentiation capacities. Normal and cancer stem cells share similar characteristics in relation to their stemness properties. One-carbon metabolism (OCM), a network of interconnected reactions, plays an important role in this dependence through its role in the endogenous synthesis of methionine and S-adenosylmethionine (SAM), the universal donor of methyl groups in eukaryotic cells. OCM genes are differentially expressed in stem cells, compared to their differentiated counterparts. Furthermore, cultivating stem cells in methionine-restricted conditions hinders their stemness capacities through decreased SAM levels with a subsequent decrease in histone methylation, notably H3K4me3, with a decrease in stem cell markers. Stem cells’ reliance on methionine is linked to several mechanisms, including high methionine flux or low endogenous methionine biosynthesis.
  • 1.2K
  • 12 Jan 2023
Topic Review Peer Reviewed
Phosphatidyl Inositol 4-Kinases
In recent decades, phosphoinositides (or PIs) have emerged as essential signaling molecules. Despite their low cellular abundance, PIs are found to be involved in various cellular processes, including cell migration, vesicular trafficking, cell cycle regulation, metabolism, cytoskeletal remodeling, autophagy, aging, apoptosis, and cell signaling. Recent studies have shown that aberrant activity of either lipid kinases or phosphatases leads to various medical implications like cancer, diabetes, and microbial infections, suggesting an essential role for these lipid molecules and enzymes in their metabolism. This entry focused on one of the critical enzymes involved in phosphoinositide metabolism: phosphatidyl inositol 4-kinase (PI4-Kinase).
  • 1.2K
  • 02 Jul 2024
Topic Review Video
Crosstalk between Apoptosis and Autophagy
Research in biomedical sciences has changed dramatically over the past fifty years. There is no doubt that the discovery of apoptosis and autophagy as two highly synchronized and regulated mechanisms in cellular homeostasis are among the most important discoveries in these decades. Along with the advancement in molecular biology, identifying the genetic players in apoptosis and autophagy has shed light on our understanding of their function in physiological and pathological conditions. Apoptosis and autophagy play essential roles in human health, and their malfunction leads to many diseases, including cancer, neurodegenerative disease, and autoimmune disorders. These mechanisms are highly regulated, and there is complex crosstalk between them.
  • 1.2K
  • 29 Mar 2022
Topic Review
Adipocyte–Macrophage Relationship in Cancer
Obesity is a major public health concern associated with chronic low-grade systemic inflammation. Moreover, obesity is considered one of the major risk factors for the development of several chronic diseases, such as cancer. Researchers describe here, how adipose tissue dysfunction, particularly alterations in adipocytes and macrophages, participate in such processes.
  • 1.2K
  • 09 Mar 2023
Topic Review
Mitochondrial Redox Signaling in Pulmonary Hypertension
Mitochondria are important organelles that act as a primary site to produce reactive oxygen species (ROS). Additionally, mitochondria play a pivotal role in the regulation of Ca2+ signaling, fatty acid oxidation, and ketone synthesis. Dysfunction of these signaling molecules leads to the development of pulmonary hypertension (PH), atherosclerosis, and other vascular diseases. Features of PH include vasoconstriction and pulmonary artery (PA) remodeling, which can result from abnormal proliferation, apoptosis, and migration of PA smooth muscle cells (PASMCs). These responses are mediated by increased Rieske iron–sulfur protein (RISP)-dependent mitochondrial ROS production and increased mitochondrial Ca2+ levels. Mitochondrial ROS and Ca2+ can both synergistically activate nuclear factor κB (NF-κB) to trigger inflammatory responses leading to PH, right ventricular failure, and death. 
  • 1.2K
  • 04 Jul 2022
Topic Review
Autonomy in Stem Cell-Derived Embryoids
The experimental production of complex structures resembling mammalian embryos (e.g., blastoids, gastruloids) from pluripotent stem cells in vitro has become a booming research field. Since some of these embryoid models appear to reach a degree of complexity that may come close to viability, a broad discussion has set in with the aim to arrive at a consensus on the ethical implications with regard to acceptability of the use of this technology with human cells. The present text focuses on developmental autonomy of embryoids which is an aspect of great ethical relevance and must receive increased attention during the preparation of new legal regulations, but which has not been included yet in the recently issued ISSCR Guidelines.  
  • 1.2K
  • 10 Nov 2021
  • Page
  • of
  • 81
Featured Entry Collections
>>

Featured Reprints

>>
Encyclopedia of Digital Society, Industry 5.0 and Smart City
Encyclopedia of Engineering
Encyclopedia of Social Sciences
Encyclopedia of Medieval Royal Iconography
Academic Video Service
Feedback