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Medicinal Plants for Eczema
Published in Namrita Lall, Medicinal Plants for Cosmetics, Health and Diseases, 2022
This causes a large number of mast cells to be present within the skin. These mast cells express NF-κB–related genes and Th-2 cytokines when exposed to an allergen (Jensen, Falkencrone, and Skov, 2014). However, these allergens release histamine into the extracellular space during a process known as degranulation (Abe et al., 1993; Hogan and Schwartz, 1997). Some of the histamines are metabolized via two alternative pathways (Abe et al., 1993). One of the pathways involves a catalyze known as histamine N-methyltransferase (EC 2.1.1.8), while the other involves a catalyze known as diamine oxidase (EC 1.4.3.6) (Castells, 2006; Abe et al., 1993).
Dermal filler complications and management
Published in Michael Parker, Charlie James, Fundamentals for Cosmetic Practice, 2022
Degranulation is, in essence, the release of said granular contents from within a cell to its surrounding environment. Regarding anaphylaxis, the mechanism of release is through a tyrosine-kinase phosphorylation cascade after a pro-inflammatory cell (such as a mast cell) has been activated by an IgE-antigen complex. The relevance of a phosphorylation cascade is that through enzymatic phosphorylation a small signal can be rapidly and significantly amplified via a short series of chemical reactions. This phosphorylation cascade results in an influx in intracellular calcium, which in itself is the trigger for degranulation to occur. When mast cells degranulate, they release pro-inflammatory mediators such as histamine, prostaglandin and cytokines such as TNF-α. See Figure 13.5.
Acute erythematous rash on the trunk and limbs
Published in Richard Ashton, Barbara Leppard, Differential Diagnosis in Dermatology, 2021
Richard Ashton, Barbara Leppard
Acute urticaria is defined as urticaria which has been present for less than 6 weeks. Individual lesions last for less than 24 hours (‘here today and gone tomorrow’). A central itchy white papule or plaque due to dermal oedema (weal) is surrounded by an erythematous flare. The lesions are variable in size and shape, and may be associated with swelling of the soft tissues of the eyelids, lips and tongue (angioedema, see p. 70). To identify how long the weals last, draw around one, and ask to see the patient the following day. Lesions which last for longer than 24 hours should be classified as urticarial dermatoses and require a biopsy for diagnosis. The weal is the result of degranulation of mast cells releasing histamine and other mediators of inflammation. Degranulation can be caused by allergic (IgE) and non-allergic stimuli.
Eosinophil exocytosis in a poorly differentiated tubular gastric adenocarcinoma: case report
Published in Ultrastructural Pathology, 2022
Rosario Caruso, Eleonora Irato, Luciana Rigoli
Eosinophil degranulation in human-diseased tissues occurs primarily through eosinophil cytolysis and PMD.3 Compound and classical exocytosis are rarely observed16,21 and predominantly described in vitro (i.e., during interaction between rat eosinophils and some parasitic helminths22; after incubation of human eosinophils with extracts from environmental fungi23 or with high concentration of TNF-alpha.24) Instead, in our case, eosinophil degranulation patterns included mainly PMD, as no eosinophil cytolysis was found. PMD occurred alone (28.3%) and in association with compound exocytosis (40%) or classical exocytosis (2.5%). These findings show similarities to the experimental model in vitro, where a high concentration of TNF-alpha evokes not only compound exocytosis but also PMD.24 This mixed degranulation pattern in the same eosinophil suggests the hypothesis of a morphological continuum that starts with PMD and culminates in exocytosis. To our knowledge, this is the first report showing compound and classical exocytosis in human gastric carcinoma.
Practical management of adverse events in patients with advanced systemic mastocytosis receiving midostaurin
Published in Expert Opinion on Biological Therapy, 2021
Jason Gotlib, Hanneke C. Kluin-Nelemans, Cem Akin, Karin Hartmann, Peter Valent, Andreas Reiter
Treatment of advSM is challenging due to the heterogeneity and complexity of the disease [2,35]. Historically, treatment options were limited to palliative therapies that were directed toward relieving symptoms of MC degranulation or anaphylaxis (e.g. antihistamines, MC stabilizers, corticosteroids, epinephrine for anaphylaxis), and cytoreductive therapies directed at MC debulking (e.g. interferon-α, cladribine, or multiagent chemotherapy) [2,35,36]. The multikinase/KIT inhibitor midostaurin demonstrated clinical benefit in two phase 2 studies in patients with advSM, regardless of KIT mutation status [15,16,37,38], which led to its approval in 2017 by the US Food and Drug Administration and the European Medicines Agency as a single agent for the treatment of patients with advSM [39,40]. Today, midostaurin is widely used in patients with advSM.
Inhibitory activity of narirutin on RBL-2H3 cells degranulation
Published in Immunopharmacology and Immunotoxicology, 2021
Liyan Niu, Jihao Wei, Xuwen Li, Yongri Jin, Xiaolei Shi
As shown in Figure 3, single cell topography looked like a shuttle in A1 and A3, but that of A2 looked like a sphere and it was brighter than A1. C2 had a much stronger stereo feeling than C1 and C3 in their 3 D topographical image. These results demonstrated that narirutin had a positive effect on stabilizing morphology of activated cells. Small holes can be observed on cell membrane of B1 and B3 obviously, in contrast, the membrane projection and holes approximately disappearing were observed in B2 cells. Muchmore, B2 cells were surrounded by more prominent unknown vesicles and granular material. That is just the fact that cell degranulation may be a process of exocytosis. In other words, there are many particles stored in cells that would be released when cells were stimulated, these vesicles from the cytoplasm to outside the membrane. More importantly, as shown in the curve, vesicles of sensitized RBL-2H3 cells had a higher height as comparing with other groups. These results showed that DNP-BSA can promote sensitized RBL-2H3 cells transfer more vesicles to the edge and supernatant of RBL-2H3 cells, and lead to cell more granules release. However, narirutin could suppress this phenomenon in a certain extent.