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CBD News: Statement by Ahmed Djoghlaf, Executive Secretary, at the Expert Workshop on Scientific and Technical Guidance on the Use of Biogeographic Classification Systems and Identification of Marine Areas in Need of Protection beyond National Jurisdictio




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CBD News: Statement by dr. Ahmed Djoghlaf, Executive Secretary, at the Special East Partnership Council Meeting: East Asian Seas Congress 2009, Manila, Philippines, 25 November 2009.




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CBD Communiqué: The President of the Philippines Declares 2010 its National Year of Biodiversity.




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CBD Press Release: Philippines President hosts South-East Asian launch of the United Nations Decade on Biodiversity




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CBD News: We, the Heads of State/Government of Brunei Darussalam, the Kingdom of Cambodia, the Republic of Indonesia, the Lao People's Democratic Republic, Malaysia, the Republic of the Union of Myanmar, the Republic of the Philippines, the Republic o




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The algebra of bounded-type holomorphic functions on the ball

Daniel Carando, Santiago Muro and Daniela M. Vieira
Proc. Amer. Math. Soc. 148 (2020), 2447-2457.
Abstract, references and article information




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A topology on the set of isomorphism classes of maximal Cohen–Macaulay modules

Naoya Hiramatsu and Ryo Takahashi
Proc. Amer. Math. Soc. 148 (2020), 2359-2369.
Abstract, references and article information




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Perturbation de la Dynamique de Diffeomorphismes en Topologie (C^{1})

Sylvain Crovisier, University of Paris-Sud - A publication of the Societe Mathematique de France, 2013, 164 pp., Softcover, ISBN-13: 978-2-85629-764-3, List: US$67, All AMS Members: US$53.60, AST/354

This memoir deals with the dynamics of diffeomorphisms of compact manifolds. For the study of generic properties or for the construction of examples,...




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Repression of sphingosine kinase (SK)-interacting protein (SKIP) in acute myeloid leukemia diminishes SK activity and its re-expression restores SK function [Molecular Bases of Disease]

Previous studies have shown that sphingosine kinase interacting protein (SKIP) inhibits sphingosine kinase (SK) function in fibroblasts. SK phosphorylates sphingosine producing the potent signaling molecule sphingosine-1-phosphate (S1P). SKIP gene (SPHKAP) expression is silenced by hypermethylation of its promoter in acute myeloid leukemia (AML). However, why SKIP activity is silenced in primary AML cells is unclear. Here, we investigated the consequences of SKIP down-regulation in AML primary cells and the effects of SKIP re-expression in leukemic cell lines. Using targeted ultra-HPLC-tandem MS (UPLC-MS/MS), we measured sphingolipids (including S1P and ceramides) in AML and control cells. Primary AML cells had significantly lower SK activity and intracellular S1P concentrations than control cells, and SKIP-transfected leukemia cell lines exhibited increased SK activity. These findings show that SKIP re-expression enhances SK activity in leukemia cells. Furthermore, other bioactive sphingolipids such as ceramide were also down-regulated in primary AML cells. Of note, SKIP re-expression in leukemia cells increased ceramide levels 2-fold, inactivated the key signaling protein extracellular signal-regulated kinase, and increased apoptosis following serum deprivation or chemotherapy. These results indicate that SKIP down-regulation in AML reduces SK activity and ceramide levels, an effect that ultimately inhibits apoptosis in leukemia cells. The findings of our study contrast with previous results indicating that SKIP inhibits SK function in fibroblasts and therefore challenge the notion that SKIP always inhibits SK activity.




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A peroxisome deficiency-induced reductive cytosol state up-regulates the brain-derived neurotrophic factor pathway [Metabolism]

The peroxisome is a subcellular organelle that functions in essential metabolic pathways, including biosynthesis of plasmalogens, fatty acid β-oxidation of very-long-chain fatty acids, and degradation of hydrogen peroxide. Peroxisome biogenesis disorders (PBDs) manifest as severe dysfunction in multiple organs, including the central nervous system (CNS), but the pathogenic mechanisms in PBDs are largely unknown. Because CNS integrity is coordinately established and maintained by neural cell interactions, we here investigated whether cell-cell communication is impaired and responsible for the neurological defects associated with PBDs. Results from a noncontact co-culture system consisting of primary hippocampal neurons with glial cells revealed that a peroxisome-deficient astrocytic cell line secretes increased levels of brain-derived neurotrophic factor (BDNF), resulting in axonal branching of the neurons. Of note, the BDNF expression in astrocytes was not affected by defects in plasmalogen biosynthesis and peroxisomal fatty acid β-oxidation in the astrocytes. Instead, we found that cytosolic reductive states caused by a mislocalized catalase in the peroxisome-deficient cells induce the elevation in BDNF secretion. Our results suggest that peroxisome deficiency dysregulates neuronal axogenesis by causing a cytosolic reductive state in astrocytes. We conclude that astrocytic peroxisomes regulate BDNF expression and thereby support neuronal integrity and function.




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G{alpha}q splice variants mediate phototransduction, rhodopsin synthesis, and retinal integrity in Drosophila [Signal Transduction]

Heterotrimeric G proteins mediate a variety of signaling processes by coupling G protein–coupled receptors to intracellular effector molecules. In Drosophila, the Gαq gene encodes several Gαq splice variants, with the Gαq1 isoform protein playing a major role in fly phototransduction. However, Gαq1 null mutant flies still exhibit a residual light response, indicating that other Gαq splice variants or additional Gq α subunits are involved in phototransduction. Here, we isolated a mutant fly with no detectable light responses, decreased rhodopsin (Rh) levels, and rapid retinal degeneration. Using electrophysiological and genetic studies, biochemical assays, immunoblotting, real-time RT-PCR, and EM analysis, we found that mutations in the Gαq gene disrupt light responses and demonstrate that the Gαq3 isoform protein is responsible for the residual light response in Gαq1 null mutants. Moreover, we report that Gαq3 mediates rhodopsin synthesis. Depletion of all Gαq splice variants led to rapid light-dependent retinal degeneration, due to the formation stable Rh1-arrestin 2 (Arr2) complexes. Our findings clarify essential roles of several different Gαq splice variants in phototransduction and retinal integrity in Drosophila and reveal that Gαq3 functions in rhodopsin synthesis.




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Biophysical characterization of SARAH domain-mediated multimerization of Hippo pathway complexes in Drosophila [Signal Transduction]

Hippo pathway signaling limits cell growth and proliferation and maintains the stem-cell niche. These cellular events result from the coordinated activity of a core kinase cassette that is regulated, in part, by interactions involving Hippo, Salvador, and dRassF. These interactions are mediated by a conserved coiled-coil domain, termed SARAH, in each of these proteins. SARAH domain–mediated homodimerization of Hippo kinase leads to autophosphorylation and activation. Paradoxically, SARAH domain–mediated heterodimerization between Hippo and Salvador enhances Hippo kinase activity in cells, whereas complex formation with dRassF inhibits it. To better understand the mechanism by which each complex distinctly modulates Hippo kinase and pathway activity, here we biophysically characterized the entire suite of SARAH domain–mediated complexes. We purified the three SARAH domains from Drosophila melanogaster and performed an unbiased pulldown assay to identify all possible interactions, revealing that isolated SARAH domains are sufficient to recapitulate the cellular assemblies and that Hippo is a universal binding partner. Additionally, we found that the Salvador SARAH domain homodimerizes and demonstrate that this interaction is conserved in Salvador's mammalian homolog. Using native MS, we show that each of these complexes is dimeric in solution. We also measured the stability of each SARAH domain complex, finding that despite similarities at both the sequence and structural levels, SARAH domain complexes differ in stability. The identity, stoichiometry, and stability of these interactions characterized here comprehensively reveal the nature of SARAH domain–mediated complex formation and provide mechanistic insights into how SARAH domain–mediated interactions influence Hippo pathway activity.




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Demographic expansion of several Amazonian archaeological cultures by computer simulation

(Universitat Pompeu Fabra - Barcelona) Expansions by groups of humans were common during prehistoric times, after the adoption of agriculture. Among other factors, this is due to population growth of farmers which was greater than of that hunter-gatherers. We can find one example of this during the Neolithic period, when farming was introduced to Europe by migrations from the Middle East.




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Four Theories and a Philosophy: Self-Management Education for Individuals Newly Diagnosed With Type 2 Diabetes

T. Chas Skinner
Apr 1, 2003; 16:
Lifestyle and Behavior




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Repression of sphingosine kinase (SK)-interacting protein (SKIP) in acute myeloid leukemia diminishes SK activity and its re-expression restores SK function [Molecular Bases of Disease]

Previous studies have shown that sphingosine kinase interacting protein (SKIP) inhibits sphingosine kinase (SK) function in fibroblasts. SK phosphorylates sphingosine producing the potent signaling molecule sphingosine-1-phosphate (S1P). SKIP gene (SPHKAP) expression is silenced by hypermethylation of its promoter in acute myeloid leukemia (AML). However, why SKIP activity is silenced in primary AML cells is unclear. Here, we investigated the consequences of SKIP down-regulation in AML primary cells and the effects of SKIP re-expression in leukemic cell lines. Using targeted ultra-HPLC-tandem MS (UPLC-MS/MS), we measured sphingolipids (including S1P and ceramides) in AML and control cells. Primary AML cells had significantly lower SK activity and intracellular S1P concentrations than control cells, and SKIP-transfected leukemia cell lines exhibited increased SK activity. These findings show that SKIP re-expression enhances SK activity in leukemia cells. Furthermore, other bioactive sphingolipids such as ceramide were also down-regulated in primary AML cells. Of note, SKIP re-expression in leukemia cells increased ceramide levels 2-fold, inactivated the key signaling protein extracellular signal-regulated kinase, and increased apoptosis following serum deprivation or chemotherapy. These results indicate that SKIP down-regulation in AML reduces SK activity and ceramide levels, an effect that ultimately inhibits apoptosis in leukemia cells. The findings of our study contrast with previous results indicating that SKIP inhibits SK function in fibroblasts and therefore challenge the notion that SKIP always inhibits SK activity.




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A peroxisome deficiency-induced reductive cytosol state up-regulates the brain-derived neurotrophic factor pathway [Metabolism]

The peroxisome is a subcellular organelle that functions in essential metabolic pathways, including biosynthesis of plasmalogens, fatty acid β-oxidation of very-long-chain fatty acids, and degradation of hydrogen peroxide. Peroxisome biogenesis disorders (PBDs) manifest as severe dysfunction in multiple organs, including the central nervous system (CNS), but the pathogenic mechanisms in PBDs are largely unknown. Because CNS integrity is coordinately established and maintained by neural cell interactions, we here investigated whether cell-cell communication is impaired and responsible for the neurological defects associated with PBDs. Results from a noncontact co-culture system consisting of primary hippocampal neurons with glial cells revealed that a peroxisome-deficient astrocytic cell line secretes increased levels of brain-derived neurotrophic factor (BDNF), resulting in axonal branching of the neurons. Of note, the BDNF expression in astrocytes was not affected by defects in plasmalogen biosynthesis and peroxisomal fatty acid β-oxidation in the astrocytes. Instead, we found that cytosolic reductive states caused by a mislocalized catalase in the peroxisome-deficient cells induce the elevation in BDNF secretion. Our results suggest that peroxisome deficiency dysregulates neuronal axogenesis by causing a cytosolic reductive state in astrocytes. We conclude that astrocytic peroxisomes regulate BDNF expression and thereby support neuronal integrity and function.




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Sphingolipids distribution at mitochondria-associated membranes (MAM) upon induction of apoptosis.

Vincent Mignard
Apr 29, 2020; 0:jlr.RA120000628v1-jlr.RA120000628
Research Articles




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Dynamics of sphingolipids and the serine palmitoyltransferase complex in rat oligodendrocytes during myelination

Deanna L. Davis
Apr 1, 2020; 61:505-522
Research Articles




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A simple method for sphingolipid analysis of tissues embedded in optimal cutting temperature compound

Timothy D Rohrbach
Apr 27, 2020; 0:jlr.D120000809v1-jlr.D120000809
Methods




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Characterization of the small molecule ARC39, a direct and specific inhibitor of acid sphingomyelinase in vitro

Eyad Naser
Mar 10, 2020; 0:jlr.RA120000682v1-jlr.RA120000682
Research Articles




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Episode 24 – The Internet of David’s Rules (IoDR) ARM, graphics cards & Twitter’s crackdown

Macworld UK’s Acting Editor David Price takes the reins for this edition, and is joined by Online Editor of Computerworld UK Scott Carey to chat about billions and billions of pounds and the acquisition of ARM by SoftBank. Second up, Staff Writer at PC Advisor and Macworld UK Christopher Minasians plugs in to the haunting world of graphics cards and makes sense of it all for the rest of us. Digital Arts Staff Writer Mimi Launder then explains why Twitter has slapped a troll right in the face in order to stand up to Internet bullying.  


See acast.com/privacy for privacy and opt-out information.




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WITHDRAWN: Structural and mechanistic studies of hydroperoxide conversions catalyzed by a CYP74 clan epoxy alcohol synthase from amphioxus (Branchiostoma floridae) [Research Articles]

This manuscript has been withdrawn by the Author.




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Characterization of the small molecule ARC39, a direct and specific inhibitor of acid sphingomyelinase in vitro [Research Articles]

Inhibition of acid sphingomyelinase (ASM), a lysosomal enzyme that catalyzes the hydrolysis of sphingomyelin into ceramide and phosphorylcholine, may serve as an investigational tool or a therapeutic intervention to control many diseases. Specific ASM inhibitors are currently not sufficiently characterized. Here, we found that 1-aminodecylidene bis-phosphonic acid (ARC39) specifically and efficiently (>90%) inhibits both lysosomal and secretory ASM in vitro. Results from investigating sphingomyelin phosphodiesterase 1 (SMPD1/Smpd1) mRNA and ASM protein levels suggested that ARC39 directly inhibits ASM’s catalytic activity in cultured cells, a mechanism which differs from that of functional inhibitors of ASM (FIASMAs). We further provide evidence that ARC39 dose- and time-dependently inhibits lysosomal ASM in intact cells, and we show that ARC39 also reduces platelet- and ASMpromoted adhesion of tumor cells. The observed toxicity of ARC39 is low at concentrations relevant for ASM inhibition in vitro, and it does not strongly alter the lysosomal compartment or induce phospholipidosis in vitro. When applied intraperitoneally in vivo, even subtoxic high doses administered short-term induced sphingomyelin accumulation only locally in the peritoneal lavage without significant accumulation in plasma, liver, spleen or brain. These findings require further investigation with other possible chemical modifications. In conclusion, our results indicate that ARC39 potently and selectively inhibits ASM in vitro and highlight the need for developing compounds that can reach tissue concentrations sufficient for ASM inhibition in vivo.




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A simple method for sphingolipid analysis of tissues embedded in optimal cutting temperature compound [Methods]

Mass spectrometry (MS) assisted lipidomic tissue analysis is a valuable tool to assess sphingolipid metabolism dysfunction in disease. These analyses can reveal potential pharmacological targets or direct mechanistic studies to better understand the molecular underpinnings and influence of sphingolipid metabolism alterations on disease etiology. But procuring sufficient human tissues for adequately powered studies can be challenging. Therefore, biorepositories, which hold large collections of cryopreserved human tissues, are an ideal retrospective source of specimens. However, this resource has been vastly underutilized by lipid biologists, as the components of optimal cutting temperature compound (OCT) used in cryopreservation are incompatible with MS analyses. Here, we report results indicating that OCT also interferes with protein quantification assays, and that the presence of OCT impacts the quantification of extracted sphingolipids by LC–ESI–MS/MS. We developed and validated a simple and inexpensive method that removes OCT from OCT-embedded tissues. Our results indicate that removal of OCT from cryopreserved tissues does not significantly affect the accuracy of sphingolipid measurements with LC–ESI–MS/MS. We used the validated method to analyze sphingolipid alterations in tumors compared with normal adjacent uninvolved lung tissues from individuals with lung cancer, and to determine the long-term stability of sphingolipids in OCT-cryopreserved normal lung tissues. We show that lung cancer tumors have significantly altered sphingolipid profiles and that sphingolipids are stable for up to 16 years in OCT-cryopreserved normal lung tissues. This validated sphingolipidomic OCT-removal protocol should be a valuable addition to the lipid biologist’s toolbox.




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Sphingolipids distribution at mitochondria-associated membranes (MAM) upon induction of apoptosis. [Research Articles]

The levels and composition of sphingolipids and related metabolites are altered in aging and common disorders such as diabetes and cancers, as well as in neurodegenerative, cardiovascular, and respiratory diseases. Changes in sphingolipids have been implicated as being an essential step in mitochondria-driven cell death. However, little is known about the precise sphingolipid composition and modulation in mitochondria or related organelles. Here, we used LC–MS/MS to analyze the presence of key components of the ceramide metabolic pathway in vivo and in vitro in purified endoplasmic reticulum (ER), mitochondria-associated membranes (MAM), and mitochondria. Specifically, we analyzed the sphingolipids in the three pathways that generate ceramide: sphinganine in the de novo ceramide pathway, sphingomyelin in the breakdown pathway, and sphingosine in the salvage pathway. We observed sphingolipid profiles in mouse liver, mouse brain, and a human glioma cell line (U251). We analyzed the quantitative and qualitative changes of these sphingolipids during staurosporine (STS)-induced apoptosis in U251 cells. Ceramide, especially C16-ceramide, levels increased during early apoptosis possibly through a conversion from mitochondrial sphinganine and sphingomyelin, but sphingosine and lactosyl- and glucosyl-ceramide levels were unaffected. We also found that ceramide generation is enhanced in mitochondria when sphingomyelin levels are decreased in the MAM. This decrease was associated with an increase in acid sphingomyelinase (ASM) activity in MAM. We conclude that meaningful sphingolipid modifications occur in MAM, the mitochondria, and ER during the early phases of apoptosis.




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Tissue-specific analysis of lipid species in Drosophila during overnutrition by UHPLC-MS/MS and MALDI-MSI [Research Articles]

Diets high in calories can be used to model metabolic diseases, including obesity and its associated comorbidities, in animals. Drosophila melanogaster fed high-sugar diets (HSDs) exhibit complications of human obesity including hyperglycemia, hyperlipidemia, insulin resistance, cardiomyopathy, increased susceptibility to infection, and reduced longevity. We hypothesize that lipid storage in the high-sugar-fed fly’s fat body (FB) reaches a maximum capacity, resulting in the accumulation of toxic lipids in other tissues or lipotoxicity. We took two approaches to characterize tissue-specific lipotoxicity. Ultra-HPLC-MS/MS and MALDI-MS imaging enabled spatial and temporal localization of lipid species in the FB, heart, and hemolymph. Substituent chain length was diet dependent, with fewer odd chain esterified FAs on HSDs in all sample types. By contrast, dietary effects on double bond content differed among organs, consistent with a model where some substituent pools are shared and others are spatially restricted. Both di- and triglycerides increased on HSDs in all sample types, similar to observations in obese humans. Interestingly, there were dramatic effects of sugar feeding on lipid ethers, which have not been previously associated with lipotoxicity. Taken together, we have identified candidate endocrine mechanisms and molecular targets that may be involved in metabolic disease and lipotoxicity.




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Dynamics of sphingolipids and the serine palmitoyltransferase complex in rat oligodendrocytes during myelination [Research Articles]

Myelin is a unique lipid-rich membrane structure that accelerates neurotransmission and supports neuronal function. Sphingolipids are critical myelin components. Yet sphingolipid content and synthesis have not been well characterized in oligodendrocytes, the myelin-producing cells of the CNS. Here, using quantitative real-time PCR, LC-MS/MS-based lipid analysis, and biochemical assays, we examined sphingolipid synthesis during the peak period of myelination in the postnatal rat brain. Importantly, we characterized sphingolipid production in isolated oligodendrocytes. We analyzed sphingolipid distribution and levels of critical enzymes and regulators in the sphingolipid biosynthetic pathway, with focus on the serine palmitoyltransferase (SPT) complex, the rate-limiting step in this pathway. During myelination, levels of the major SPT subunits increased and oligodendrocyte maturation was accompanied by extensive alterations in the composition of the SPT complex. These included changes in the relative levels of two alternative catalytic subunits, SPTLC2 and -3, in the relative levels of isoforms of the small subunits, ssSPTa and -b, and in the isoform distribution of the SPT regulators, the ORMDLs. Myelination progression was accompanied by distinct changes in both the nature of the sphingoid backbone and the N-acyl chains incorporated into sphingolipids. We conclude that the distribution of these changes among sphingolipid family members is indicative of a selective channeling of the ceramide backbone toward specific downstream metabolic pathways during myelination. Our findings provide insights into myelin production in oligodendrocytes and suggest how dysregulation of the biosynthesis of this highly specialized membrane could contribute to demyelinating diseases.




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Elevated First-Trimester Neutrophil Count Is Closely Associated with the Development of Maternal Gestational Diabetes Mellitus and Adverse Pregnancy Outcomes

Chronic low-grade inflammation plays a central role in the pathophysiology of gestational diabetes mellitus (GDM). In order to investigate the ability of different inflammatory blood cell parameters in predicting the development of GDM and pregnancy outcomes, 258 women with GDM and 1154 women without were included in this retrospective study. First-trimester neutrophil count outperformed white blood cell (WBC) count, and neutrophil-to-lymphocyte ratio (NLR) in the predictability for GDM. Subjects were grouped based on tertiles of neutrophil count during their first-trimester pregnancy. The results showed that as the neutrophil count increased, there was a step-wise increase in GDM incidence, as well as glucose and glycosylated hemoglobin (HbA1c) level, Homeostasis Model Assessment for Insulin Resistance (HOMA-IR), macrosomia incidence and newborn weight. Neutrophil count was positively associated with pre-pregnancy Body Mass Index (BMI), HOMA-IR and newborn weight. Additionally, neutrophil count was an independent risk factor for the development of GDM, regardless of the history of GDM. Spline regression showed that there was a significant linear association between GDM incidence and continuous neutrophil count when it exceeded 5.0 x 109/L. This work suggested that first-trimester neutrophil count is closely associated with the development of GDM and adverse pregnancy outcomes.




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Two- and three-color STORM analysis reveals higher-order assembly of leukotriene synthetic complexes on the nuclear envelope of murine neutrophils [Computational Biology]

Over the last several years it has become clear that higher order assemblies on membranes, exemplified by signalosomes, are a paradigm for the regulation of many membrane signaling processes. We have recently combined two-color direct stochastic optical reconstruction microscopy (dSTORM) with the (Clus-DoC) algorithm that combines cluster detection and colocalization analysis to observe the organization of 5-lipoxygenase (5-LO) and 5-lipoxygenase–activating protein (FLAP) into higher order assemblies on the nuclear envelope of mast cells; these assemblies were linked to leukotriene (LT) C4 production. In this study we investigated whether higher order assemblies of 5-LO and FLAP included cytosolic phospholipase A2 (cPLA2) and were linked to LTB4 production in murine neutrophils. Using two- and three-color dSTORM supported by fluorescence lifetime imaging microscopy we identified higher order assemblies containing 40 molecules (median) (IQR: 23, 87) of 5-LO, and 53 molecules (62, 156) of FLAP monomer. 98 (18, 154) molecules of cPLA2 were clustered with 5-LO, and 77 (33, 114) molecules of cPLA2 were associated with FLAP. These assemblies were tightly linked to LTB4 formation. The activation-dependent close associations of cPLA2, FLAP, and 5-LO in higher order assemblies on the nuclear envelope support a model in which arachidonic acid is generated by cPLA2 in apposition to FLAP, facilitating its transfer to 5-LO to initiate LT synthesis.




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Inhibition of glycosphingolipid biosynthesis reverts multidrug resistance by differentially modulating ABC transporters in chronic myeloid leukemias [Cell Biology]

Multidrug resistance (MDR) in cancer arises from cross-resistance to structurally- and functionally-divergent chemotherapeutic drugs. In particular, MDR is characterized by increased expression and activity of ATP-binding cassette (ABC) superfamily transporters. Sphingolipids are substrates of ABC proteins in cell signaling, membrane biosynthesis, and inflammation, for example, and their products can favor cancer progression. Glucosylceramide (GlcCer) is a ubiquitous glycosphingolipid (GSL) generated by glucosylceramide synthase, a key regulatory enzyme encoded by the UDP-glucose ceramide glucosyltransferase (UGCG) gene. Stressed cells increase de novo biosynthesis of ceramides, which return to sub-toxic levels after UGCG mediates incorporation into GlcCer. Given that cancer cells seem to mobilize UGCG and have increased GSL content for ceramide clearance, which ultimately contributes to chemotherapy failure, here we investigated how inhibition of GSL biosynthesis affects the MDR phenotype of chronic myeloid leukemias. We found that MDR is associated with higher UGCG expression and with a complex GSL profile. UGCG inhibition with the ceramide analog d-threo-1-(3,4,-ethylenedioxy)phenyl-2-palmitoylamino-3-pyrrolidino-1-propanol (EtDO-P4) greatly reduced GSL and monosialotetrahexosylganglioside levels, and co-treatment with standard chemotherapeutics sensitized cells to mitochondrial membrane potential loss and apoptosis. ABC subfamily B member 1 (ABCB1) expression was reduced, and ABCC-mediated efflux activity was modulated by competition with nonglycosylated ceramides. Consistently, inhibition of ABCC-mediated transport reduced the efflux of exogenous C6-ceramide. Overall, UGCG inhibition impaired the malignant glycophenotype of MDR leukemias, which typically overcomes drug resistance through distinct mechanisms. This work sheds light on the involvement of GSL in chemotherapy failure, and its findings suggest that targeted GSL modulation could help manage MDR leukemias.




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PPARA Polymorphism Influences the Cardiovascular Benefit of Fenofibrate in Type 2 Diabetes: Findings From ACCORD-Lipid

Mario Luca Morieri
Apr 1, 2020; 69:771-783
Genetics/Genomes/Proteomics/Metabolomics




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A Polymorphism in the Glucocorticoid Receptor Gene, Which Decreases Sensitivity to Glucocorticoids In Vivo, Is Associated With Low Insulin and Cholesterol Levels

Elisabeth F.C. van Rossum
Oct 1, 2002; 51:3128-3134
Genetics




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Graphic showing the role of satellite images in tracking environmental damage

1 June 2012 , Volume 68, Number 4

Eyes in the skies keeping watch on a planet under stress. Click on the PDF link to view the graphic


Graphic




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Mark Wignal | A case for political agility, Dr Phillips

Many of us may feel right at this minute that in the same way the 19th-century American poet Edgar Allan Poe painted it in his tortured poem, The Conqueror Worm, we are sitting in a theatre, watching a play of hopes and fears “While the orchestra...




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Peter Phillips | Protecting our people is priority in the COVID-19 fight

The national priority at this time must be the protection of the Jamaican people against the onset of COVID-19. This has to be done by striking the balance between implementing protective public-health measures and providing a supporting economic...




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PPARA Polymorphism Influences the Cardiovascular Benefit of Fenofibrate in Type 2 Diabetes: Findings From ACCORD-Lipid

The cardiovascular benefits of fibrates have been shown to be heterogeneous and to depend on the presence of atherogenic dyslipidemia. We investigated whether genetic variability in the PPARA gene, coding for the pharmacological target of fibrates (PPAR-α), could be used to improve the selection of patients with type 2 diabetes who may derive cardiovascular benefit from addition of this treatment to statins. We identified a common variant at the PPARA locus (rs6008845, C/T) displaying a study-wide significant influence on the effect of fenofibrate on major cardiovascular events (MACE) among 3,065 self-reported white subjects treated with simvastatin and randomized to fenofibrate or placebo in the ACCORD-Lipid trial. T/T homozygotes (36% of participants) experienced a 51% MACE reduction in response to fenofibrate (hazard ratio 0.49; 95% CI 0.34–0.72), whereas no benefit was observed for other genotypes (Pinteraction = 3.7 x 10–4). The rs6008845-by-fenofibrate interaction on MACE was replicated in African Americans from ACCORD (N = 585, P = 0.02) and in external cohorts (ACCORD-BP, ORIGIN, and TRIUMPH, total N = 3059, P = 0.005). Remarkably, rs6008845 T/T homozygotes experienced a cardiovascular benefit from fibrate even in the absence of atherogenic dyslipidemia. Among these individuals, but not among carriers of other genotypes, fenofibrate treatment was associated with lower circulating levels of CCL11—a proinflammatory and atherogenic chemokine also known as eotaxin (P for rs6008845-by-fenofibrate interaction = 0.003). The GTEx data set revealed regulatory functions of rs6008845 on PPARA expression in many tissues. In summary, we have found a common PPARA regulatory variant that influences the cardiovascular effects of fenofibrate and that could be used to identify patients with type 2 diabetes who would derive benefit from fenofibrate treatment, in addition to those with atherogenic dyslipidemia.




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Mitochondrial Proton Leak Regulated by Cyclophilin D Elevates Insulin Secretion in Islets at Nonstimulatory Glucose Levels

Fasting hyperinsulinemia precedes the development of type 2 diabetes. However, it is unclear whether fasting insulin hypersecretion is a primary driver of insulin resistance or a consequence of the progressive increase in fasting glycemia induced by insulin resistance in the prediabetic state. Herein, we have discovered a mechanism that specifically regulates non–glucose-stimulated insulin secretion (NGSIS) in pancreatic islets that is activated by nonesterified free fatty acids, the major fuel used by β-cells during fasting. We show that the mitochondrial permeability transition pore regulator cyclophilin D (CypD) promotes NGSIS, but not glucose-stimulated insulin secretion, by increasing mitochondrial proton leak. Islets from prediabetic obese mice show significantly higher CypD-dependent proton leak and NGSIS compared with lean mice. Proton leak–mediated NGSIS is conserved in human islets and is stimulated by exposure to nonesterified free fatty acids at concentrations observed in obese subjects. Mechanistically, proton leak activates islet NGSIS independently of mitochondrial ATP synthesis but ultimately requires closure of the KATP channel. In summary, we have described a novel nonesterified free fatty acid–stimulated pathway that selectively drives pancreatic islet NGSIS, which may be therapeutically exploited as an alternative way to halt fasting hyperinsulinemia and the progression of type 2 diabetes.




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18F-Fluorocholine PET/CT in Primary Hyperparathyroidism: Superior Diagnostic Performance to Conventional Scintigraphic Imaging for Localization of Hyperfunctioning Parathyroid Glands

Primary hyperparathyroidism (PHPT) is a common endocrine disorder, definitive treatment usually requiring surgical removal of the offending parathyroid glands. To perform focused surgical approaches, it is necessary to localize all hyperfunctioning glands. The aim of the study was to compare the efficiency of established conventional scintigraphic imaging modalities with emerging 18F-fluorocholine PET/CT imaging in preoperative localization of hyperfunctioning parathyroid glands in a larger series of PHPT patients. Methods: In total, 103 patients with PHPT were imaged preoperatively with 18F-fluorocholine PET/CT and conventional scintigraphic imaging methods, consisting of 99mTc-sestamibi SPECT/CT, 99mTc-sestamibi/pertechnetate subtraction imaging, and 99mTc-sestamibi dual-phase imaging. The results of histologic analysis, as well as intact parathyroid hormone and serum calcium values obtained 1 d after surgery and on follow-up, served as the standard of truth for evaluation of imaging results. Results: Diagnostic performance of 18F-fluorocholine PET/CT surpassed conventional scintigraphic methods (separately or combined), with calculated sensitivity of 92% for PET/CT and 39%–56% for conventional imaging (65% for conventional methods combined) in the entire patient group. Subgroup analysis, differentiating single and multiple hyperfunctioning parathyroid glands, showed PET/CT to be most valuable in the group with multiple hyperfunctioning glands, with sensitivity of 88%, whereas conventional imaging was significantly inferior, with sensitivity of 22%–34% (44% combined). Conclusion: 18F-fluorocholine PET/CT is a diagnostic modality superior to conventional imaging methods in patients with PHPT, allowing for accurate preoperative localization.




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Immigrants and WIOA Services: Comparison of Sociodemographic Characteristics of Native- and Foreign-Born Adults in the United States

As federal and state governments ramp up efforts to implement the Workforce Innovation and Opportunity Act, these fact sheets compare key characteristics of the foreign born and the U.S. born that are relevant to understanding needs for adult education and workforce training services. The fact sheets cover the United States, the 20 states and 25 counties with the largest immigrant populations, and New York City.




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Dual Language Learners: A National Demographic and Policy Profile

As the share of U.S. children under age 8 who are Dual Language Learners (DLLs) increases, state policies have an important role to play in ensuring all young learners are able to get their education off to a good start. These fact sheets compare key characteristics of DLLs and their peers nationwide and in 30 states, and identify state policies that support equitable access to high-quality early childhood education and care programs.




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English Learners in Select States: Demographics, Outcomes, and State Accountability Policies

States are in the midst of designing new policies to hold schools accountable for the education of English Learner (EL) students, as mandated by the federal Every Student Succeeds Act (ESSA). This series of fact sheets sketches the characteristics of immigrant and EL students in 25 states, the gaps between their educational outcomes and those of their peers, and the accountability policies each state is developing.




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On the Brink of Demographic Crisis, Governments in East Asia Turn Slowly to Immigration

With many countries in East Asia facing unfavorable demographic shifts in the form of aging populations, low fertility, and shrinking workforces, governments in 2016 continued to explore immigration as a potential policy solution. However, a tradition of cultural homogeneity and wariness among publics about increased immigration is leading policymakers to test the waters with very small steps.




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The Philippines: Beyond Labor Migration, Toward Development and (Possibly) Return

In the Philippines, a pervasive culture of migration has led millions to seek opportunities abroad, particularly since an economic downturn in the 1970s. The government has long embraced exporting labor as official economic policy, but over time, the focus has shifted: first to protecting workers overseas and much more recently to linking migration and development. This article explores the evolution of Filipino migration policy and trends.




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French Philosopher Latour Urges No Return to Pre-Lockdown Normal

Source:

What if rather than hurrying back to a pre-lockdown "business as usual" to revive economies hammered by the coronavirus pandemic, countries built a new normal where the fight against climate change was paramount?






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Colts QB Philip Rivers to coach at Alabama high school once NFL career ends

Indianapolis Colts quarterback Philip Rivers will become the head football coach at St. Michael Catholic High School, the school announced Friday.




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Drug may curb dangerous urges in pedophiles, study says

A testosterone-lowering drug can reduce male pedophiles' risk of sexually abusing children, according to a new Swedish study.




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Phishing email claims to be from ADA president

At least one American Dental Association member has reported receiving a phishing email appearing to come from an address containing ADA President Chad P. Gehani's name and including a link to "view member's details."




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Association warns members on potential coronavirus-related phishing emails

The Association is asking member dentists and their dental teams to increase their vigilance over phishing emails as a result of the coronavirus, known as COVID-19.
Attackers often use emergencies as an opportunity to send fake emails tailored to that situation, the association said.




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Check out this Awesome Special Education Infographic by USC Rossier





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State Sociodemographic Portraits of Immigrant and U.S.-Born Parents of Young Children

These fact sheets provide a sociodemographic sketch of parents with children ages 0 to 8 in the 30 states with the largest number of immigrant families, offering data and analysis of some of the key parental characteristics to help stakeholders identify populations that could be targets for early childhood and parent-focused programs working to improve child and parent outcomes.