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Topic Review
Chondrosarcoma Resistance to Radiation Therapy
Chondrosarcoma is a malignant cartilaginous tumor that is particularly chemoresistant and radioresistant to X-rays. The first line of treatment is surgery, though this is almost impossible in some specific locations. Such resistances can be explained by the particular composition of the tumor, which develops within a dense cartilaginous matrix, producing a resistant area where the oxygen tension is very low. 
  • 869
  • 19 Apr 2023
Topic Review
Pathophysiology of Sickle Cell Disease
Sickle cell disease (SCD) is the most common hemoglobinopathy worldwide. It is characterized by an impairment of shear stress-mediated vasodilation, a pro-coagulant, and a pro-adhesive state orchestrated among others by the depletion of the vasodilator nitric oxide, by the increased phosphatidylserine exposure and tissue factor expression, and by the increased interactions of erythrocytes with endothelial cells that mediate the overexpression of adhesion molecules such as VCAM-1, respectively. Extracellular vesicles (EVs) have been shown to be novel actors involved in SCD pathophysiological processes. Medium-sized EVs, also called microparticles, which exhibit increased plasma levels in this pathology, were shown to induce the activation of endothelial cells, thereby increasing neutrophil adhesion, a key process potentially leading to the main complication associated with SCD, vaso-occlusive crises (VOCs). Small-sized EVs, also named exosomes, which have also been reported to be overrepresented in SCD, were shown to potentiate interactions between erythrocytes and platelets, and to trigger endothelial monolayer disruption, two processes also known to favor the occurrence of VOCs.
  • 869
  • 26 Sep 2022
Topic Review
Tooth Cementum Annulation
Tooth Cementum Annulation (or TCA) is a technique that relies on the analysis of the incremental growth of dental cementum for age and season at death estimation.
  • 867
  • 27 Jul 2022
Topic Review
Tibial Hemimelia's Deformity Reconstruction Surgery
Tibial hemimelia is a rare congenital deficiency with a wide spectrum of pathology and deformity. This paper aims to give a comprehensive review of tibial hemimelia, with a concise summary of the history, pathology, and clinical findings of tibial hemimelia, while providing treatment recommendations and a review of the current literature. Classifications and surgical treatments are discussed, including amputation, limb reconstruction, and lengthening.
  • 866
  • 28 Jun 2021
Topic Review
Matrix Metalloproteinases Inhibition
Matrix metalloproteinases are enzymes that degrade the extracellular matrix. They have different substrates but similar structural organization. Matrix metalloproteinases are involved in many physiological and pathological processes and there is a need to develop inhibitors for these enzymes in order to modulate the degradation of the extracellular matrix (ECM). There exist two classes of inhibitors: endogenous and synthetics. The development of synthetic inhibitors remains a great challenge due to the low selectivity and specificity, side effects in clinical trials, and instability. 
  • 866
  • 30 Jun 2021
Topic Review
Application of Barley Tweaky Spike Mutants
Barley developmental mutants tweaky spike (tw) with disturbed auxin pathways possess a unique feature of an increased level of mouldy germinating grains (MGG), which serves as a convenient model to investigate the effects of plant immunity-related substances. The effects of the auxin 2,4-dichlorophenoxyacetic acid (2,4-D), auxin inhibitors, salicylic acid (SA), and trans-cinnamic acid (TCA) were studied using the tw-WT system in surface-sterilized and unsterilized germinating grains under high rates of natural infection. Significant differences among the allelic tw mutants were revealed at the natural MGG level and in response to 2,4-D, SA, and TCA. The most effective means against MGG were sterilization and TCA. 2,4-D inhibited root growth in tw and tw2 mutants, occurring only in unsterilized and not sterilized germinating grains, while the opposite was observed for TCA and SA. The tw mutations influenced variations in the seed-borne fungal spectra, decreasing the frequency of Bipolaris sorokiniana and increasing Fusarium spp. Hypochlorite-based surface sterilization methods should be used with caution in studies where the action of exogenous 2,4-D will be analysed in germinating grains. Auxin pathway disturbances specific for pleiotropic tw mutants are generally restricted to organogenesis but not to germination events. 
  • 864
  • 29 Oct 2021
Topic Review
B Lymphocytes in Brief
B lymphocytes, or B cells, are essential warriors of our immune system, playing a central role in defending the body against infections and diseases. These specialized white blood cells originate in the bone marrow, where they undergo a complex maturation process. B cells possess unique membrane-bound receptors called B cell receptors (BCRs) that enable them to recognize specific antigens on pathogens. When a BCR binds to its corresponding antigen, it triggers a chain reaction leading to B cell activation. Activated B cells have two main fates: they can transform into plasma cells, dedicated antibody factories that churn out antibodies to neutralize pathogens, or become memory B cells. Memory B cells "remember" past infections, allowing for a swift and potent immune response upon re-exposure to the same pathogen. In essence, B lymphocytes are the guardians of our immune memory, enabling our bodies to fight off invaders and stay resilient against future threats.
  • 863
  • 08 Oct 2023
Topic Review
Non-Classical Exosomes for Osteoarthritis Treatment
Osteoarthritis of the knee is one of the most common chronic, debilitating musculoskeletal conditions. Exosomes derived from non-classical sources (not bone marrow or adipose derived MSCs derived MSCs) for osteoarthritis of the knee have potential clinical use.
  • 859
  • 18 Jun 2021
Topic Review
HDL in Sepsis and SARS-CoV-2
High-density lipoproteins (HDLs) are a class of blood particles, principally involved in mediating reverse cholesterol transport from peripheral tissue to liver. Omics approaches have identified crucial mediators in the HDL proteomic and lipidomic profile, which are involved in distinct pleiotropic functions. Besides their role as cholesterol transporter, HDLs display anti-inflammatory, anti-apoptotic, anti-thrombotic, and anti-infection properties. Experimental and clinical studies have unveiled significant changes in both HDL serum amount and composition that lead to dysregulated host immune response and endothelial dysfunction in the course of sepsis. Most SARS-Coronavirus-2-infected patients admitted to the intensive care unit showed common features of sepsis disease, such as the overwhelmed systemic inflammatory response and the alterations in serum lipid profile. Despite relevant advances, episodes of mild to moderate acute kidney injury (AKI), occurring during systemic inflammatory diseases, are associated with long-term complications, and high risk of mortality. The multi-faceted relationship of kidney dysfunction with dyslipidemia and inflammation encourages to deepen the clarification of the mechanisms connecting these elements.
  • 857
  • 11 Jun 2021
Topic Review
Possible Mechanisms of the Invasiveness of Pueraria montana
Pueraria montana var. lobata is native to East Asia, and was introduced to many countries due to its potential for multiple uses. This species escaped under the management conditions soon after its introduction, and became a harmful weed species. This species has been listed in the top 100 of the world’s worst invasive alien species. P. montana stands expand quickly and threaten the native flora and fauna including microbiota. This species affects the concentration of carbon and nitrogen in soil and aquatic environments, and increases the amount of pollutants in the local atmosphere. Its infestation also causes serious economic losses on forestry and agriculture. 
  • 857
  • 19 Oct 2023
Topic Review
Epigenetic Regulation of Myogenesis
Skeletal muscle development and regeneration rely on the successive activation of specific transcription factors that engage cellular fate, promote commitment, and drive differentiation. Emerging evidence demonstrates that epigenetic regulation of gene expression is crucial for the maintenance of the cell differentiation status upon division and, therefore, to preserve a specific cellular identity. This depends in part on the regulation of chromatin structure and its level of condensation. Chromatin architecture undergoes remodeling through changes in nucleosome composition, such as alterations in histone post-translational modifications or exchange in the type of histone variants. 
  • 856
  • 16 Dec 2021
Topic Review
Rice Diurnal Flower-Opening Times
The principal goal of rice (Oryza sativa L.) breeding is to increase the yield. In the past, hybrid rice was mainly indica intra-subspecies hybrids, but its yield has been difficult to improve. The hybridization between the indica and japonica subspecies has stronger heterosis; the utilization of inter-subspecies heterosis is important for long-term improvement of rice yields. However, the different diurnal flower-opening times (DFOTs) between the indica and japonica subspecies seriously reduce the efficiency of cross-pollination and yield and increase the cost of indica–japonica hybrid rice seeds, which has become one of the main constraints for the development of indica–japonica hybrid rice breeding. The DFOT of plants is adapted to their growing environment and is also closely related to species stability and evolution. 
  • 856
  • 14 Jul 2023
Topic Review
Antiparasitic Activity of Betulinic Acid and Its Derivatives
Betulinic acid (BA) is a triterpene natural product which has shown antiparasitic activity against Leishmania, Trypanosoma cruzi, and Plasmodium. 
  • 855
  • 31 May 2022
Topic Review
List of Species Found in Antarctica
Antarctica is one of the most physically and chemically extreme terrestrial environments to be inhabited by lifeforms. The largest plants are mosses, and the largest animals that do not leave the continent are a few species of insects.
  • 854
  • 01 Nov 2022
Topic Review
Fungal Host Defence
Humans have developed complex immune systems that defend against invading microbes, including fungal pathogens. Many highly specialized cells of the immune system share the ability to store antimicrobial compounds in membrane bound organelles that can be immediately deployed to eradicate or inhibit growth of invading pathogens. These membrane-bound organelles consist of secretory vesicles or granules, which move to the surface of the cell, where they fuse with the plasma membrane to release their contents in the process of degranulation. Lymphocytes, macrophages, neutrophils, mast cells, eosinophils, and basophils all degranulate in fungal host defence. While anti-microbial secretory vesicles are shared among different immune cell types, information about each cell type has emerged independently leading to an uncoordinated and confusing classification of granules and incomplete description of the mechanism by which they are deployed. While there are important differences, there are many similarities in granule morphology, granule content, stimulus for degranulation, granule trafficking, and release of granules against fungal pathogens.
  • 852
  • 30 Jun 2021
Topic Review
Clostridioides Difficile Biofilm
The microbiota inhabiting the intestinal tract provide several critical functions to its host. Microorganisms found at the mucosal layer form organized three-dimensional structures which are considered to be biofilms. Their development and functions are influenced by host factors, host-microbe interactions, and microbe-microbe interactions. These structures can dictate the health of their host by strengthening the natural defenses of the gut epithelium or cause disease by exacerbating underlying conditions. Biofilm communities can also block the establishment of pathogens and prevent infectious diseases. Although these biofilms are important for colonization resistance, new data provide evidence that gut biofilms can act as a reservoir for pathogens such as Clostridioides difficile.
  • 848
  • 19 Nov 2021
Topic Review
miRNA in Molecular Diagnostics
miRNAs influence the expression of numerous proteins, including the expression of tumor suppressors and protooncogenes, thus becoming oncogenes and tumor suppressors themselves. As the same miRNA can have different targets in different tissues, its function will also be different in different types of tumors, depending on the intracellular milieu and the set of proteins for which its translation is modulated. Therefore, the same miRNA can act as a tumor suppressor and an oncogene in different tumors. Even in the same tumor, the same miRNA can be involved in regulation circles with feedback loops and potentially affect both tumor suppressors and oncogenes. As 50% of miRNA genes are located in regions associated with cancers, their expression is found to be deregulated in tumors. miRNAs were found to be members of signaling circuits, often involving also long non-coding RNAs (lnc RNAs) and circular RNAs (cRNAs).
  • 847
  • 22 Sep 2022
Topic Review
MicroRNAs and Oxidative Stress
Emerging evidence reveals that oxidative stress has a critical role in the development of type 2 diabetes. Overproduction of reactive oxygen species can promote an imbalance between the production and neutralization of antioxidant defence systems, thus favoring lipid accumulation, cellular stress, and the activation of cytosolic signaling pathways, and inducing β-cell dysfunction, insulin resistance, and tissue inflammation. Over the last few years, microRNAs (miRNAs) have attracted growing attention as important mediators of diverse aspects of oxidative stress. These small endogenous non-coding RNAs of 19–24 nucleotides act as negative regulators of gene expression, including the modulation of redox signaling pathways. 
  • 844
  • 03 Jun 2021
Topic Review
Eosinophilic Pneumonia
Eosinophilic pneumonia (EP), including acute EP and chronic EP, is characterized by the massive pulmonary infiltration of eosinophils into the lung. However, the mechanisms underlying the selective accumulation of eosinophils in EP have not yet been fully elucidated. We reported that bronchoalveolar lavage fluid (BALF) from EP patients induced the transmigration of eosinophils across endothelial cells in vitro. The concentrations of eotaxin-2 (CCL24) and monocyte chemotactic protein (MCP)-4 (CCL13), which are CC chemokine receptor (CCR) 3 ligands, were elevated in the BALF of EP patients, and anti-CCR3 monoclonal antibody inhibited the eosinophil transmigration induced by the BALF of EP patients. The concentration of macrophage inflammatory protein 1β (CCL4), a CCR5 ligand that induces eosinophil migration, was increased in the BALF of EP patients. Furthermore, the concentration of interleukin (IL) 5 was increased in the BALF of EP patients, and it has been reported that anti-IL-5 antibody treatment resulted in remission and the reduction of glucocorticoid use in some cases of chronic EP. The concentrations of lipid mediators, such as leukotriene (LT) B4, damage-associated molecular pattern molecules (DAMPs), such as uric acid, or extracellular matrix proteins, such as periostin, were also increased in the BALF of EP patients. These findings suggest that chemokines, such as CCR3/CCR5 ligands, cytokines, such as IL-5, lipid mediators, such as LTB4, DAMPs, and extracellular matrix proteins may play roles in the accumulation or activation of eosinophils in EP.
  • 844
  • 21 Jun 2021
Topic Review
Discovery of NPs by Genomics/Metabolomics
Natural products (NPs) are evolutionarily optimized as drug-like molecules and remain the most consistently successful source of drugs and drug leads. Due to traditional discovery approaches’ limitations relying on untargeted screening methods, there is a growing trend to employ unconventional secondary metabolomics techniques.
  • 844
  • 13 Jul 2021
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