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Topic Review
Biography
Topic Review
Spleen Reparative Regeneration
The spleen is the largest lymphoid unpaired parenchymal organ of the abdominal cavity found in all vertebrates. Spleen is able to regenerate, though not necessarily to the initial volume. The recovery lasts one month and preserves the architecture, albeit with an increase in the relative volume of lymphoid follicles. The renovated tissues, however, exhibit skewed functional profiles; notably, the decreased production of antibodies and the low cytotoxic activity of T cells, consistent with the decline of T-dependent zones and prolonged reduction in T cell numbers. Autotransplantations of splenic material are of particular clinical interest, as the procedure can possibly mitigate the development of post-splenectomy syndrome. Under these conditions, regeneration lasts 1-2 months, depending on the species. The transplants effectively destroy senescent erythrocytes, assist in microbial clearance, and produce antibodies, thus averting sepsis and bacterial pneumonia. Meanwhile, cellular sources of splenic recovery in such models remain obscure, as well as the time required for T and B cell number re-constitution.
733
21 Jun 2022
Topic Review
Mesenchymal Stem Cell-Derived Exosomes
Mesenchymal stem cells (MSCs) are multipotent stem cells that can be isolated from human tissues or organs, such as the bone marrow, adipose tissue, umbilical cord, lung, spleen, liver or kidney, while exosomes are crucial components that account for the paracrine action of MSCs. They are extracellular vesicles with a lipid bilayer structure and an average diameter of 100 nm, and they perform biological function by transferring bioactive molecules such as miRNAs, lncRNAs, lipids and cytokines.
732
27 Jan 2021
Topic Review
Muse Cells
Muse cells, identified as pluripotent surface marker, stage-specific embryonic antigen (SSEA)-3(+), are endogenous reparative pluripotent stem cells distributed in the bone marrow, peripheral blood and connective tissue of every organ. Since they are non-tumorigenic and do not require gene introduction or cytokine treatment to be rendered pluripotent and induce differentiation, they elicit few safety concerns. They can be delivered intravenously and do not require surgery for their administration since they selectively home to damaged site by sphingosine-1-phosphate (S1P)-S1PR2 axis after intravenous injection. Donor-Muse cells can be used without HLA-matching test or immunosuppressant treatment since they have a specific immunomodulatory system represented by HLA-G expression.
730
12 Oct 2021
Topic Review
Astrocyte–Neuron Crosstalk
Astrocyte-neuron crosstalk is a phenomenon in which both of those cell types depend on each other and support their development, genes expression, metabolism, excitability and plasticity. Astrocyte–neuron crosstalk incontrovertibly plays a crucial role in shaping neuronal metabolism. It has been shown that it substantially affects the expression of basal metabolic enzymes in both types of cells, by essentially unknown factor(s) which are released to extracellular space directly and using extracellular vesicles-packed molecules and by cell-to-cell contacts. Additionally, astrocytes support neurons with lactate, which (when secreted during enhanced neuronal activity events) stimulates a formation and maintenece of long-term plastycity phenomena in neurons.
728
29 Sep 2020
Topic Review
VEGF
VEGF-A (also called VEGF) is a member of the mammalian platelet-derived growth factor (PDGF) supergene family which also includes VEGF-B, VEGF-C, VEGF-D and placental growth factor (PlGF).
728
05 May 2021
Topic Review
Taste Receptors and Sperm Biology
Taste receptors were first described as sensory receptors located on the tongue, where they are expressed in small clusters of specialized epithelial cells. Taste receptors and components of the coupled taste transduction cascade are also expressed during the different phases of spermatogenesis as well as in mature spermatozoa from mouse to humans and the overlap between the ligand spectrum of taste receptors with compounds in the male and female reproductive organs makes it reasonable to assume that sperm “taste” these different cues in their natural microenvironments.
727
17 Jan 2022
Topic Review
Sample Entropy
Sample entropy, fractal dimension, Lyapunov exponent used as nonlinear measures, and assessment of the variability of the center of pressure during standing using force plate.
725
14 Dec 2020
Topic Review
PDE2A for Mouse Liver Development
cAMP and cGMP are intracellular signaling molecules produced in response to a plethora of extracellular signals in order to coordinate cellular metabolism, proliferation, differentiation and apoptosis. Phosphodiesterases (PDEs) are the enzymes that hydrolyze cAMP and cGMP in order to end or to limit the responses to these signals. To date 11 PDE families (named PDE1 to PDE11) have been identified across each cell type expressed in a peculiar pattern. They enclose 21 genes that codify approximately 100 enzymes that form a redundant network ensuring the compensation of activity in case of alteration of activity or lack of expression of one of the members. PDE2A, a cAMP-hydrolyzing enzyme, represents the exception to this picture, as PDE2A knockout is embryonic lethal. Knockout embryos show that the lack of the enzyme has the greatest impact on the development of the heart and of the liver, which is no longer able to assume its hematopoietic role. The increase of the intracellular cAMP level and the downregulation of the anti-apoptotic gene Bcl2 might explain the loss of integrity in the PDE2A knockout liver niche that compromises the hematopoietic function and maturation.
725
29 Oct 2020
Topic Review
Mast Cell Functions
Mast cells (MCs) are well-known as key effector cells of type I allergic reactions, commonly named anaphylactic responses.
725
02 Feb 2021
Topic Review
MTOR Signalling
In the liver, mTORC1, which consists of mTOR, mammalian lethal with Sec13 protein 8 (mLST8), Dishevelled, Egl-10 and Pleckstrin domain-containing mTOR-interacting protein (Deptor), regulatory-associated protein of mTOR (Raptor) and proline-rich protein kinase B (Akt) substrate (Pras40), is critical for controlling metabolic processes.
724
27 Oct 2020
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