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Topic Review
Platelet-Derived Extracellular Vesicles
Platelet-derived extracellular vesicles (pEVs) are nanosized membranous subcellular structures released by platelets, which comprise different subpopulations that differ on morphology, size, composition and cellular origin. Extracellular vesicles (EVs) work as intercellular communicators exerting their function by transporting their cargo that includes nucleic acids, proteins and lipids. pEVs have shown to mediate same functions as platelets, presenting  a great potential for the development of new treatments in the biomedical field. 
  • 583
  • 18 Aug 2021
Topic Review
Platelet Concentrates
Platelet concentrates (PCs) typically refer to a group of materials produced from autologous blood designed to improve tissue regeneration.
  • 563
  • 19 Feb 2021
Topic Review
Platelet Biology
Platelets are generated from megakaryocytes in a multi-step process called thrombopoiesis regulated by thrombopoietin. Thrombopoietin stimulates its receptor in megakaryocytes to induce the genesis of pro-platelets via a mechanism activated by low platelet counts. Platelet counts in blood are controlled by the rates of production and removal, involving mechanisms of platelet clearance, activation or ageing. Platelets are the most numerous circulating cell type (≈200,000/µL blood in humans) with an immune function. 
  • 528
  • 14 Feb 2022
Topic Review
Plasticity of Human RPE Cells
The retina is a specialized light-sensitive tissue in the eye of mammals and humans that provides visual perception, and is actively studied at the cellular, molecular and genetic levels. Photoreceptor cells located in its outer part perform the function of converting light (phototransduction) into neurochemical signals, which are processed in the neurons of the retina and the brain and ultimately form our vision. Functional support for retinal neurons is provided by retinal pigment epithelium cells (RPE cells). The retinal pigment epithelium (RPE) is a single-row layer of pigmented, hexagonal, normally non-proliferating cells located between the choroid and the photoreceptor cells of the retina. The RPE performs many diverse functions to support the retina, including the transepithelial transport of substances, the phagocytosis of photoreceptor outer segments, and a number of processes in the visual cycle, as well as participation in the blood–retinal barrier and secretion of growth factors. The RPE plays an important role in regulating the redox homeostasis of retinal photoreceptors. A few cells have been isolated from the human RPE, which, according to strict clonal analysis and other stem cell criteria (self-renewal and the production of differential progeny), were classified as adult RPE stem cells (RPESCs). The number of  mammalian RPESCs was determined in vitro experiments, from which it became clear that  to 2% of cells are capable of proliferation, self-renewal, and the expression of specific genes characterizing stem cells. Depending on microenvironmental conditions, RPESCs can remain quiescent in a stemness state or exhibit multipotent differentiation. RPESCs can produce RPE cells and are capable of generating different types of photoreceptors and nerve cells, or mesenchymal cells.
  • 168
  • 15 Mar 2024
Topic Review
Plasmodium falciparum Development from Gametocyte to Oocyst
Malaria elimination never succeed without the implementation of transmission-blocking strategies. The transmission of Plasmodium spp. parasites from the human host to the mosquito vector depends on circulating gametocytes in the peripheral blood of the vertebrate host. Once ingested by the mosquito during blood meals, these sexual forms undergo a series of radical morphological and metabolic changes to survive and progress from the gut to the salivary glands, where they will be waiting to be injected into the vertebrate host. The design of effective transmission-blocking strategies requires a thorough understanding of all the mechanisms that drive the development of gametocytes, gametes, sexual reproduction, and subsequent differentiation within the mosquito. The drastic changes in Plasmodium falciparum shape and function throughout its life cycle rely on the tight regulation of stage-specific gene expression.
  • 379
  • 01 Sep 2023
Topic Review
Plasma Membrane Ion Channels on Bone Remodeling
The extracellular milieu is a rich source of different stimuli and stressors. Some of them depend on the chemical–physical features of the matrix, while others may come from the ‘outer’ environment, as in the case of mechanical loading applied on the bones. In addition to these forces, a plethora of chemical signals drives cell physiology and fate, possibly leading to dysfunctions when the homeostasis is disrupted. This variety of stimuli triggers different responses among the tissues: bones represent a particular milieu in which a fragile balance between mechanical and metabolic demands should be tuned and maintained by the concerted activity of cell biomolecules located at the interface between external and internal environments. Plasma membrane ion channels can be viewed as multifunctional protein machines that act as rapid and selective dual-nature hubs, sensors, and transducers.
  • 333
  • 24 Mar 2023
Topic Review
Plant-RNA in Extracellular Vesicles
The release of extracellular vesicles (EVs) is a common language, used by living organisms from different kingdoms as a means of communication between them. Extracellular vesicles are lipoproteic particles that contain many biomolecules, such as proteins, nucleic acids, and lipids. The primary role of EVs is to convey information to the recipient cells, affecting their function. Plant-derived extracellular vesicles (PDEVs) can be isolated from several plant species, and the study of their biological properties is becoming an essential starting point to study cross-kingdom communication, especially between plants and mammalians. 
  • 343
  • 19 Apr 2022
Topic Review
Plant Stinging Hairs
True stinging hairs are highly specialized plant structures that are able to inject a physiologically active liquid into the skin. They can be classified into two basic types: Urtica-type stinging hairs with the classical “hypodermic syringe” mechanism expelling only liquid, and Tragia-type stinging hairs expelling a liquid together with a sharp crystal. Since the middle of the 20th century, neurotransmitters(acetylcholine, histamine, serotonin) have been repeatedly detected in stinging hairs of Urticaceae; these substances can explain some of the physiological effects of stinging hairs, but fail to completely explain neuropathic effects, pointing to some yet unidentified neurotoxins. 
  • 2.3K
  • 22 Sep 2021
Topic Review
Plant Meiosis
Meiosis is an essential cell-division process for ensuring genetic diversity across generations. Meiotic recombination ensures the accuracy of genetic interchange between homolous chromosomes and segregation of parental alleles. Programmed DNA double-strand breaks (DSBs), catalyzed by the evolutionarily conserved topoisomerase VIA (a subunit of the archaeal type II DNA topoisomerase)-like enzyme Spo11 and several other factors, is a distinctive feature of meiotic recombination initiation.
  • 311
  • 22 Jun 2022
Topic Review
Pivotal Role of Inflammation in Celiac Disease
Celiac disease (CD) is an immune mediate disease characterised by gluten dependent T-cell mediated activation, autoimmunity and derangement of the intestinal mucosa in a specific genetic background. Although the activation of the T-cells has been studied in dept, the central question remains still unanswered, namely, why a pro-inflammatory T cell response to gluten is generated instead of a regulatory response, which normally promotes oral tolerance to dietary protein antigens. There is an inflamed environment in CD intestine, enriched in cytokines, such as IL-15, or type I interferons, in which T cells tend to acquire a pro- inflammatory phenotype. The factors that create a pro-inflammatory environment in the CD intestine, leading to an expansion of gliadin-specific T cells in genetically susceptible individuals and further shifting them towards a pro-inflammatory phenotype, remain to be identified. Gluten exacerbates these constitutive alterations, by increasing the same markers already altered before the gluten introduction, both in vitro and in vivo. All these new observations add this disease “tout court” to the big family of increasing chronic inflammatory diseases where nutrients can have pro-inflammatory or anti-inflammatory effects, directly or indirectly mediated by the intestinal microbiota, where the intestine functions as a cross road for the control of the inflammation both local and at distance.
  • 455
  • 20 Jul 2022
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