The 'ideal square' of logographic scripts and the structural similarities of Khitan script and han'gul

A comparison of the Khitan Small Script and Korean han'gŭl shows a striking structural similarity of two essentially phonetic scripts that combine 'letters' into large blocks. These blocks in han'gŭl correspond to the syllable, whereas in Khitan they correspond to the word-level. I shall compare these two systems structurally with both the linear alphasyllabic principle of Brahmi-derived scripts and the principle of an 'ideal square' (or 'ideal oblong') that characterizes Chinese, Egyptian or Mayan logographic scripts in order to establish why the Khitan and Korean scripts share a rare structural principle

5-oxoETE triggers nociception in constipation-predominant irritable bowel syndrome through MAS-related G protein-coupled receptor D.

Irritable bowel syndrome (IBS) is a common gastrointestinal disorder that is characterized by chronic abdominal pain concurrent with altered bowel habit. Polyunsaturated fatty acid (PUFA) metabolites are increased in abundance in IBS and are implicated in the alteration of sensation to mechanical stimuli, which is defined as visceral hypersensitivity. We sought to quantify PUFA metabolites in patients with IBS and evaluate their role in pain. Quantification of PUFA metabolites by mass spectrometry in colonic biopsies showed an increased abundance of 5-oxoeicosatetraenoic acid (5-oxoETE) only in biopsies taken from patients with IBS with predominant constipation (IBS-C). Local administration of 5-oxoETE to mice induced somatic and visceral hypersensitivity to mechanical stimuli without causing tissue inflammation. We found that 5-oxoETE directly acted on both human and mouse sensory neurons as shown by lumbar splanchnic nerve recordings and Ca2+ imaging of dorsal root ganglion (DRG) neurons. We showed that 5-oxoETE selectively stimulated nonpeptidergic, isolectin B4 (IB4)-positive DRG neurons through a phospholipase C (PLC)- and pertussis toxin-dependent mechanism, suggesting that the effect was mediated by a G protein-coupled receptor (GPCR). The MAS-related GPCR D (Mrgprd) was found in mouse colonic DRG afferents and was identified as being implicated in the noxious effects of 5-oxoETE. Together, these data suggest that 5-oxoETE, a potential biomarker of IBS-C, induces somatic and visceral hyperalgesia without inflammation in an Mrgprd-dependent manner. Thus, 5-oxoETE may play a pivotal role in the abdominal pain associated with IBS-C.BBSRC BB/R006210/1 to James R F Hockley and Ewan St John Smith Rosetrees 834 Postdoctoral Grant (A1296) awarded to James R F Hockley and Ewan St John Smit

Ipomoeassin F Binds Sec61α to Inhibit Protein Translocation

Funding Information: We thank the Arkansas Nano & Bio Materials Characterization Facility at the Institute for Nano Sciences & Engineering for our imaging studies, and Prof Yoshito Kishi (Harvard University) for the kind gift of synthetic mycolactone A/B used by S.H. and R.S. W.S. is supported by Grant No. R15GM116032 from the National Institute of General Medical Sciences of the National Institutes of Health (NIH) and startup funds from the University of Arkansas. This work was also supported in part by Grant No. P30 GM103450 from the National Institute of General Medical Sciences of the NIH and by seed money from the Arkansas Biosciences Institute (ABI). S.O’K. is the recipient of a Biotechnology and Biological Sciences Research Council (BBSRC) Doctoral Training Programme Award (BB/J014478/ 1), and S.H. holds a Welcome Trust Investigator Award in Science (204957/Z/16/Z). The alpha-1 antitrypsin work was supported by the Alpha-1 Foundation (J.I. and M.J.I.). J.I. and M.J.H. were supported by the intramural program of NCATS, National Institutes of Health, projects 1ZIATR000048-03 (J.I.) and ZIATR000063-04 (M.J.H.). R.S. holds a Welcome Trust Investigator Award in Science (202843/Z/16/Z). C.D. received funding from the Institut Pasteur, the Institut National de la Santé et de la Recherche Med́ icale, and the Fondation Raoul Follereau. N.B.’s synthesis and chemical biology studies of mycolactone were supported by CNRS, Université de Strasbourg, Fondations Potier et Follereau, and the Investisse-ment d’Avenir (Idex Unistra). V.O.P. is supported by the Academy of Finland (Grants 289737 and 314672) and the Sigrid Juselius Foundation. Funding Information: We thank the Arkansas Nano & Bio Materials Characterization Facility at the Institute for Nano Sciences & Engineering for our imaging studies, and Prof Yoshito Kishi (Harvard University) for the kind gift of synthetic mycolactone A/B used by S.H. and R.S. W.S. is supported by Grant No. R15GM116032 from the National Institute of General Medical Sciences of the National Institutes of Health (NIH) and startup funds from the University of Arkansas. This work was also supported in part by Grant No. P30 GM103450 from the National Institute of General Medical Sciences of the NIH and by seed money from the Arkansas Biosciences Institute (ABI). S.O'K. is the recipient of a Biotechnology and Biological Sciences Research Council (BBSRC) Doctoral Training Programme Award (BB/J014478/1), and S.H. holds a Welcome Trust Investigator Award in Science (204957/Z/16/Z). The alpha-1 antitrypsin work was supported by the Alpha-1 Foundation (J.I. and M.J.I.). J.I. and M.J.H. were supported by the intramural program of NCATS, National Institutes of Health, projects 1ZIATR000048-03 (J.I.) and ZIATR000063-04 (M.J.H.). R.S. holds a Welcome Trust Investigator Award in Science (202843/Z/16/Z). C.D. received funding from the Institut Pasteur, the Institut National de la Sante et de la Recherche Medicale, and the Fondation Raoul Follereau. N.B.'s synthesis and chemical biology studies of mycolactone were supported by CNRS, Universite de Strasbourg, Fondations Potier et Follereau and the Investissement d'Avenir (Idex Unistra). V.O.P. is supported by the Academy of Finland (Grants 289737 and 314672) and the Sigrid Juselius Foundation. Publisher Copyright: © 2019 American Chemical Society.Ipomoeassin F is a potent natural cytotoxin that inhibits growth of many tumor cell lines with single-digit nanomolar potency. However, its biological and pharmacological properties have remained largely unexplored. Building upon our earlier achievements in total synthesis and medicinal chemistry, we used chemical proteomics to identify Sec61 alpha (protein transport protein Sec61 subunit alpha isoform 1), the pore-forming subunit of the Sec61 protein translocon, as a direct binding partner of ipomoeassin F in living cells. The interaction is specific and strong enough to survive lysis conditions, enabling a biotin analogue of ipomoeassin F to pull down Sec61 alpha from live cells, yet it is also reversible, as judged by several experiments including fluorescent streptavidin staining, delayed competition in affinity pulldown, and inhibition of TNF biogenesis after washout. Sec61 alpha forms the central subunit of the ER protein translocation complex, and the binding of ipomoeassin F results in a substantial, yet selective, inhibition of protein translocation in vitro and a broad ranging inhibition of protein secretion in live cells. Lastly, the unique resistance profile demonstrated by specific amino acid single-point mutations in Sec61 alpha provides compelling evidence that Sec61 alpha is the primary molecular target of ipomoeassin F and strongly suggests that the binding of this natural product to Sec61 alpha is distinctive. Therefore, ipomoeassin F represents the first plant-derived, carbohydrate-based member of a novel structural class that offers new opportunities to explore Sec61 alpha function and to further investigate its potential as a therapeutic target for drug discovery.Peer reviewe

Graphic loans: East Asia and beyond

The national languages of East Asia (Chinese, Japanese, Korean and Vietnamese) have made extensive use of a type of linguistic borrowing sometimes referred to as a 'graphic loan'. Such loans have no place in the conventional classification of loans based on Haugen (1950) or Weinreich (1953), and research on loan word theory and phonology generally overlooks them. The classic East Asian phenomenon is discussed and a framework is proposed to describe its mechanism. It is argued that graphic loans are more than just 'spelling pronunciations', because they are a systematic and widespread process, independent of but not inferior to phonological borrowing. The framework is then expanded to cover a range of other cases of borrowing between languages to show that graphic loans are not a uniquely East Asian phenomenon, and therefore need to be considered as a major category of loan

Computational modeling of Takotsubo cardiomyopathy: effect of spatially varying β-adrenergic stimulation in the rat left ventricle

In Takotsubo cardiomyopathy, the left ventricle shows apical ballooning combined with basal hypercontractility. Both clinical observations in humans and recent experimental work on isolated rat ventricular myocytes suggest the dominant mechanisms of this syndrome are related to acute catecholamine overload. However, relating observed differences in single cells to the capacity of such alterations to result in the extreme changes in ventricular shape seen in Takotsubo syndrome is difficult. By using a computational model of the rat left ventricle, we investigate which mechanisms can give rise to the typical shape of the ventricle observed in this syndrome. Three potential dominant mechanisms related to effects of β-adrenergic stimulation were considered: apical-basal variation of calcium transients due to differences in L-type and sarco(endo)plasmic reticulum Ca2+-ATPase activation, apical-basal variation of calcium sensitivity due to differences in troponin I phosphorylation, and apical-basal variation in maximal active tension due to, e.g., the negative inotropic effects of p38 MAPK. Furthermore, we investigated the interaction of these spatial variations in the presence of a failing Frank-Starling mechanism. We conclude that a large portion of the apex needs to be affected by severe changes in calcium regulation or contractile function to result in apical ballooning, and smooth linear variation from apex to base is unlikely to result in the typical ventricular shape observed in this syndrome. A failing Frank-Starling mechanism significantly increases apical ballooning at end systole and may be an important additional factor underpinning Takotsubo syndrome. </jats:p

Ipomoeassin F Binds Sec61α to Inhibit Protein Translocation

The ipomoeassin family of natural resin glycosides is underexplored chemical space with potent antitumor activity revealed in the NCI-60 cell lines screen; however, its mode of action has so far remained unexplored. In this manuscript, we report our chemical proteomics and subsequent biology studies that transform our collective knowledge of the ipomoeassin glycolipids from Organic Synthesis and Medicinal Chemistry to biological mechanism and provide a step change in our understanding of its action at a cellular level. Hence, we created an ipomoeassin F-based biotin affinity probe and used it in live cells to isolate the ER membrane protein Sec61α as its presumptive molecular target. A direct interaction between Sec61α and ipomoeassin F was confirmed by cell imaging, pulldown from purified ER membranes and competition studies using a photo-crosslinking analogue of the cyclodepsipeptide cotransin, a known Sec61α inhibitor. Crucially, we then showed that ipomoeassin F binding has a profound effect on Sec61 function, using both in vitro and in vivo assays for protein translocation and protein secretion respectively. Although structurally quite distinct, the potency of ipomoeassin F is comparable to that of mycolactone, a recently identified and intensely studied inhibitor of Sec61. The ~1,000 fold increase in the ipomoeassin F resistance of two cell lines expressing mutant forms of Sec61α strongly supports our conclusion that the effect of the compound on Sec61α is the primary basis for its potent cytotoxicity. However, we also provide evidence that ipomoeassin F is mechanistically distinct from known Sec61α inhibitors, suggesting that it is a novel structural class that may offer new opportunities to explore the Sec61 protein translocation complex as a therapeutic target for drug discovery

5-oxoETE triggers nociception in constipation-predominant irritable bowel syndrome through MAS-related G protein-coupled receptor D

Irritable bowel syndrome (IBS) is a common gastrointestinal disorder that is characterized by chronic abdominal pain concurrent with altered bowel habit. Polyunsaturated fatty acid (PUFA) metabolites are increased in abundance in IBS and are implicated in the alteration of sensation to mechanical stimuli, which is defined as visceral hypersensitivity. We sought to quantify PUFA metabolites in patients with IBS and evaluate their role in pain. Quantification of PUFA metabolites by mass spectrometry in colonic biopsies showed an increased abundance of 5-oxoeicosatetraenoic acid (5-oxoETE) only in biopsies taken from patients with IBS with predominant constipation (IBS-C). Local administration of 5-oxoETE to mice induced somatic and visceral hypersensitivity to mechanical stimuli without causing tissue inflammation. We found that 5-oxoETE directly acted on both human and mouse sensory neurons as shown by lumbar splanchnic nerve recordings and Ca2+ imaging of dorsal root ganglion (DRG) neurons. We showed that 5-oxoETE selectively stimulated nonpeptidergic, isolectin B4 (IB4)-positive DRG neurons through a phospholipase C (PLC)- and pertussis toxin-dependent mechanism, suggesting that the effect was mediated by a G protein-coupled receptor (GPCR). The MAS-related GPCR D (Mrgprd) was found in mouse colonic DRG afferents and was identified as being implicated in the noxious effects of 5-oxoETE. Together, these data suggest that 5-oxoETE, a potential biomarker of IBS-C, induces somatic and visceral hyperalgesia without inflammation in an Mrgprd-dependent manner. Thus, 5-oxoETE may play a pivotal role in the abdominal pain associated with IBS-C.status: publishe