Eosinophils promote corneal wound healing via the 12/15-lipoxygenase pathway.

Lipid mediators play important roles in regulating inflammatory responses and tissue homeostasis. Since 12/15-lipoxygenase (12/15-LOX)-derived lipid mediators such as lipoxin A4 (LXA4 ) and protectin D1 (PD1) protect against corneal epithelial cell damage, the major cell types that express 12/15-LOX and contribute to the corneal wound healing process are of particular interest. Here, we found that eosinophils were the major cell type expressing 12/15-LOX during the corneal wound healing process. Eosinophils were recruited into the conjunctiva after corneal epithelium wounding, and eosinophil-deficient and/or eosinophil-specific 12/15-LOX knockout mice showed delayed corneal wound healing compared with wild-type mice. Liquid chromatography-tandem mass spectrometry (LC-MS/MS)-based mediator lipidomics revealed that a series of 12/15-LOX-derived mediators were significantly decreased in eosinophil-deficient mice and topical application of 17-hydroxydocosahexaenoic acid (17-HDoHE), a major 12/15-LOX-derived product, restored the phenotype. These results indicate that 12/15-LOX-expressing eosinophils, by locally producing pro-resolving mediators, significantly contribute to the corneal wound healing process in the eye.

Phosphatidylserine synthesis controls oncogenic B cell receptor signaling in B cell lymphoma.

Cancer cells harness lipid metabolism to promote their own survival. We screened 47 cancer cell lines for survival dependency on phosphatidylserine (PS) synthesis using a PS synthase 1 (PTDSS1) inhibitor and found that B cell lymphoma is highly dependent on PS. Inhibition of PTDSS1 in B cell lymphoma cells caused a reduction of PS and phosphatidylethanolamine levels and an increase of phosphoinositide levels. The resulting imbalance of the membrane phospholipidome lowered the activation threshold for B cell receptor (BCR), a B cell-specific survival mechanism. BCR hyperactivation led to aberrant elevation of downstream Ca2+ signaling and subsequent apoptotic cell death. In a mouse xenograft model, PTDSS1 inhibition efficiently suppressed tumor growth and prolonged survival. Our findings suggest that PS synthesis may be a critical vulnerability of malignant B cell lymphomas that can be targeted pharmacologically.

Effect of wearing masks on odor detection and recognition.

BACKGROUND: The effect of wearing masks on olfaction remains unclear. OBJECTIVES: This study aimed to clarify the differences between the effects of no masks, surgical masks, and N95 respirator masks by conducting both identification and threshold olfaction tests. METHODS: Young, healthy volunteers aged ≥ 18 years and < 30 years without awareness of apparent olfactory disorder were included. All participants filled out a questionnaire on olfaction and completed an acuity smell identification test (Open Essence test) and an olfactory threshold test (T&T olfactometry) while wearing no masks, surgical masks, or N95 respirator masks. RESULTS: In the Open Essence tests, the no-mask group score was significantly higher than those of the surgical- and N95-mask groups. Using T&T olfactometry, the median-detection threshold of the no-mask group was significantly lower than that of the surgical-mask group, and the surgical-mask group threshold was significantly lower than that of the N95-mask group. Similar patterns were observed for the median-recognition threshold. CONCLUSIONS: Wearing masks, especially an N95 mask, reduces the ability to detect and identify odors. This disadvantage should be considered by professionals such as healthcare workers, who require proper olfaction to perform appropriate tasks.

A new species of the subterranean millipede genus Antrokoreana Verhoeff, 1938 from the Nanatsuoguchi Mine, central Honshu, Japan, and insights into the phylogenetic position of Antrokoreana (Diplopoda, Julida, Nemasomatidae).

A new species of the subterranean millipede genus Antrokoreana Verhoeff, 1938, A. asuwaensis sp. nov., from the Nanatsuoguchi Mine in central Honshu, Japan, is described based on both sexes. The new species is clearly distinguished from all congeners by the distally expanded coxal process of its anterior gonopods. Characteristics of the antennomere VII, mandibular pectinate lamellae, and flagella of anterior gonopods provide insight into the diagnostic features of Antrokoreana. Nuclear 28S ribosomal RNA as well as mitochondrial cytochrome c oxidase subunit I and 16S ribosomal RNA sequences of the new species are provided, and its phylogenetic position is preliminary estimated based on the 28S and 16S rRNA sequences. The obtained phylogenies show non-monophyly of the three genera of Nemasomatidae suggesting the possibility that Antrokoreana forms a clade that is distinct from that of the other nemasomatid genera.

Potent and Selective PTDSS1 Inhibitors Induce Collateral Lethality in Cancers with PTDSS2 Deletion.

SIGNIFICANCE: This study identifies a specific dependency on PTDSS1 for phosphatidylserine synthesis following PTDSS2 deletion and introduces novel PTDSS1 inhibitors as a therapeutic option to induce collateral lethality in cancer with PTDSS2 loss.

Development of an externally controllable sealed isotope generator.

An externally controllable sealed isotope generator has been proposed for radiation education activities. Column (68Ge-68Ga and 137Cs-137mBa) and solvent extraction (68Ge-68Ga)-based isotope generators were applied as radioactive sources. These generators showed high milking efficiencies and low breakthrough after repeated uses, and are expected to promote the use of isotope generators without radioactive contamination or the emission of radioactive waste. This isotope generator provides a new concept for sealed radioisotope sources.

Emerging roles of eosinophils and eosinophil-derived lipid mediators in the resolution of inflammation.

Acute inflammation and its resolution are essential processes for tissue protection and homeostasis. Once thought to be a passive process, the resolution of inflammation is now shown to involve active biochemical programs that enable inflamed tissues to return to homeostasis. The mechanisms by which acute inflammation is resolved are of interest, and research in recent years has uncovered new endogenous anti-inflammatory and pro-resolving lipid mediators (i.e., lipoxins, resolvins, protectin, and maresin) generated from polyunsaturated fatty acids (PUFAs). This review presents new insights into the cellular and molecular mechanisms of inflammatory resolution, especially the roles of eosinophils, and a series of omega-3 PUFA-derived anti-inflammatory lipid mediators that they generate.