Howardcrosby5907

© 2020 The Authors. Head & Neck published by Wiley Periodicals, Inc.AIMS Utilization of l-asparaginase has been one of the effective strategies for the treatment of lymphoblastic leukaemia. Since the currently used bacterial l-asparaginase causes side effects, searching for new enzyme sources has been an active field of research. This study focuses on the characterization of an l-asparaginase-producing fungal strain. METHODS AND RESULTS Sarocladium strictum was identified as a potent enzyme-producing strain. For the enhancement of enzyme production, we used two-level factorial design and response surface methodology. The optimization of significant factors showed a 1·84-fold increase in enzyme production. The Km and Vmax values of the enzyme were 9·74 mmol l-1 and 8·19 μmol min-1 . The toxicity of the produced l-asparaginase was measured on K562 and HL60 cancer cell lines and L6 as normal cells. The IC50 values were calculated as 0·4 and 0·5 IU ml-1 for K562 and HL60 respectively and no significant effect was observed in L6. BrdU proliferation and caspase-3 activity assay in l-asparaginase treated HL60 and K562 cells indicated that cell proliferation rates and apoptotic cell death were reduced. CONCLUSIONS The cytotoxic properties of the produced fungal enzyme indicated significant growth inhibition in cancer cells while having a little toxic effect on normal cells. The possibility of mass production alongside having suitable cytotoxic and kinetic properties suggest the probable use of the produced l-asparaginase for further researches as a potential chemotherapeutic agent. SIGNIFICANCE AND IMPACT OF THE STUDY The lack of significant l-glutaminase activity and promising toxicity properties in S. strictum and the closer evolutionary relativeness of fungi enzymes to human enzymes compared to bacterial enzymes suggest a new source with lower toxicity and anti-cancerous properties, causing less side effect problems. © 2020 The Society for Applied Microbiology.OBJECTIVES To describe the clinical and sonographic characteristics of malignant ovarian yolk sac tumors. METHODS In this retrospective multicenter-study we included 21 patients with a histological diagnosis of ovarian yolk sac tumor where still images and/or videoclips were available. Ten patients collected from the IOTA-studies, had undergone a standardized preoperative ultrasound examination by an experienced ultrasound examiner between 1999 and 2016. The remaining eleven were identified through medical files, where images were retrieved from local image work stations and PACs systems. All tumors were described using IOTA terminology. The collected images and video clips were used for additional characterization by two observers. RESULTS All cases were pure yolk sac tumors except for one, that was a mixed tumor (80% yolk sac tumor and 20% embryonic carcinoma). Median age at diagnosis was 25 (Interquartile range, IQR 19.5-30.5) years. Seventy-six percent (16/21) were FIGO stage I-II when diagnosed. selleck kinase inhibitor 58% (11/ne-textured, and slightly hyperechoic solid tissue, giving them a characteristic appearance. CONCLUSION Malignant ovarian yolk sac tumors are often detected at an early stage, in young women usually in the second or third decade of life, presenting with pain and markedly elevated S-AFP. On ultrasound yolk sac tumors are mostly unilateral, large, multilocular-solid or solid, with fine-textured slightly hyperechoic solid tissue, and rich vascularization. This article is protected by copyright. All rights reserved. Copyright © 2020 ISUOG. Published by John Wiley & Sons Ltd.In vertebrates, fast saltatory conduction along myelinated axons relies on the node of Ranvier. How nodes assemble on CNS neurons is not yet fully understood. We previously described that node-like clusters can form prior to myelin deposition in hippocampal GABAergic neurons and are associated with increased conduction velocity. Here, we used a live imaging approach to characterize the intrinsic mechanisms underlying the assembly of these clusters prior to myelination. We first demonstrated that their components can partially preassemble prior to membrane targeting and determined the molecular motors involved in their trafficking. We then demonstrated the key role of the protein β2Nav for node-like clustering initiation. We further assessed the fate of these clusters when myelination proceeds. Our results shed light on the intrinsic mechanisms involved in node-like clustering prior to myelination and unravel a potential role of these clusters in node of Ranvier formation and in guiding myelination onset. © 2020 Wiley Periodicals, Inc.Cellular senescence is stress-induced, irreversible growth arrest, and is thought to impair tissue function. The clearance of senescent cells can delay the features of senescence. Herein, we report the development of plasmonic core-shell spiky nanorods (CSNRs) surface-modified with an anti-beta-2-microglobulin (aB2MG) antibody and triphenylphosphonium (TPP), to target the mitochondria in senescent cells. aB2MG-TPP@CSNRs irradiated with near-infrared (NIR) light selectively caused mitochondrial damage and apoptosis of senescent cells with relatively low NIR light power, and the ability of CSNRs to activate and amplify the immune response in vitro and in vivo was discovered. The photo-induced generation of reactive oxygen species (ROS) resulted in senescent-cell apoptosis and immune adjuvant effect by CSNRs accelerated the clearance of senescent cells in mice. This study opens the way for the use of precisely regulated plasmonic nanostructures for immune adjuvant and photo-induced apoptosis for age-related senescence. © 2020 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.The 3d-metal mediated nitrene transfer is under intense scrutiny due to its potential as an atom economic and ecologically benign way for the directed amination of (un)functionalised C-H bonds. Here we present the isolation and characterisation of a rare, trigonal imido cobalt(III) complex, which bears a rather long cobalt-imido bond. It can cleanly cleave strong C-H bonds with an bond dissociation energy of up to 92 kcal/mol in an intermolecular fashion, unprecedented for imido cobalt complexes. This resulted in the amido cobalt(II) complex [Co(hmds) 2 (NH t Bu)] - . Kinetic studies on this reaction revealed an H atom transfer mechanism. Remarkably, the cobalt(II) amide itself is capable of mediating H atom abstraction or stepwise proton/electron transfer depending on the substrate. A cobalt mediated catalytic application for substrate dehydrogenation using an organo azide is presented. © 2020 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.