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Trimethylbenzenes (Interagency Science Discussion Draft)

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The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Complex chemical composition of colored surface films formed from reactions of propanal in sulfuric acid at upper troposphere/lower stratosphere aerosol acidities

Authors: Van Wyngarden, AL; Perez-Montano, S; Bui, JVH; Li, ESW; Nelson, TE; Ha, KT; Leong, L; Iraci, LT (2015) Atmospheric Chemistry and Physics 15:4225-4239. HERO ID: 2902441

[Less] Particles in the upper troposphere and lower stratosphere (UT/LS) consist mostly of concentrated sulfuric . . . [More] Particles in the upper troposphere and lower stratosphere (UT/LS) consist mostly of concentrated sulfuric acid (40-80 wt %) in water. However, airborne measurements have shown that these particles also contain a significant fraction of organic compounds of unknown chemical composition. Acid-catalyzed reactions of carbonyl species are believed to be responsible for significant transfer of gas phase organic species into tropospheric aerosols and are potentially more important at the high acidities characteristic of UT/LS particles. In this study, experiments combining sulfuric acid (H2SO4) with propanal and with mixtures of propanal with glyoxal and/or methylglyoxal at acidities typical of UT/LS aerosols produced highly colored surface films (and solutions) that may have implications for aerosol properties. In order to identify the chemical processes responsible for the formation of the surface films, attenuated total reflectance-Fourier transform infrared (ATR-FTIR) and H-1 nuclear magnetic resonance (NMR) spectroscopies were used to analyze the chemical composition of the films. Films formed from propanal were a complex mixture of aldol condensation products, acetals and propanal itself. The major aldol condensation products were the dimer (2-methyl-2-pentenal) and 1,3,5-trimethylbenzene that was formed by cyclization of the linear aldol condensation trimer. Additionally, the strong visible absorption of the films indicates that higher-order aldol condensation products must also be present as minor species. The major acetal species were 2,4,6-triethyl-1,3,5-trioxane and longer-chain linear polyacetals which are likely to separate from the aqueous phase. Films formed on mixtures of propanal with glyoxal and/or methylglyoxal also showed evidence of products of cross-reactions. Since cross-reactions would be more likely than self-reactions under atmospheric conditions, similar reactions of aldehydes like propanal with common aerosol organic species like glyoxal and methylglyoxal have the potential to produce significant organic aerosol mass and therefore could potentially impact chemical, optical and/or cloud-forming properties of aerosols, especially if the products partition to the aerosol surface.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Catalytic Upgrading of 5-Hydroxymethylfurfural to Drop-in Biofuels by Solid Base and Bifunctional Metal-Acid Catalysts

Authors: Bohre, A; Saha, B; Abu-Omar, MM (2015) ChemSusChem 8:4022-4029. HERO ID: 3044606

[Less] Design and synthesis of effective heterogeneous catalysts for the conversion of biomass intermediates . . . [More] Design and synthesis of effective heterogeneous catalysts for the conversion of biomass intermediates into long chain hydrocarbon precursors and their subsequent deoxygenation to hydrocarbons is a viable strategy for upgrading lignocellulose into distillate range drop-in biofuels. Herein, we report a two-step process for upgrading 5-hydroxymethylfurfural (HMF) to C9 and C11 fuels with high yield and selectivity. The first step involves aldol condensation of HMF and acetone with a water tolerant solid base catalyst, zirconium carbonate (Zr(CO3 )x ), which gave 92 % C9 -aldol product with high selectivity at nearly 100 % HMF conversion. The as-synthesised Zr(CO3 )x was analysed by several analytical methods for elucidating its structural properties. Recyclability studies of Zr(CO3 )x revealed a negligible loss of its activity after five consecutive cycles over 120 h of operation. Isolated aldol product from the first step was hydrodeoxygenated with a bifunctional Pd/Zeolite-β catalyst in ethanol, which showed quantitative conversion of the aldol product to n-nonane and 1-ethoxynonane with 40 and 56 % selectivity, respectively. 1-Ethoxynonane, a low oxygenate diesel range fuel, which we report for the first time in this paper, is believed to form through etherification of the hydroxymethyl group of the aldol product with ethanol followed by opening of the furan ring and hydrodeoxygenation of the ether intermediate.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Comprehensive Analysis of Structure Activity Relationships of α-Ketoheterocycles as sn-1-Diacylglycerol Lipase α Inhibitors

Authors: Janssen, FJ; Baggelaar, MP; Hummel, JJ; Overkleeft, HS; Cravatt, BF; Boger, DL; van der Stelt, M (2015) HERO ID: 3044598

[Less] Diacylglycerol lipase α (DAGLα) is responsible for the formation of the endocannabinoid 2-arachidonoylglycerol . . . [More] Diacylglycerol lipase α (DAGLα) is responsible for the formation of the endocannabinoid 2-arachidonoylglycerol (2-AG) in the central nervous system. DAGLα inhibitors are required to study the physiological role of 2-AG. Previously, we identified the α-ketoheterocycles as potent and highly selective DAGLα inhibitors. Here, we present the first comprehensive structure-activity relationship study of α-ketoheterocycles as DAGLα inhibitors. Our findings indicate that the active site of DAGLα is remarkably sensitive to the type of heterocyclic scaffold with oxazolo-4N-pyridines as the most active framework. We uncovered a fundamental substituent effect in which electron-withdrawing meta-oxazole substituents increased inhibitor potency. (C6-C9)-acyl chains with a distal phenyl group proved to be the most potent inhibitors. The integrated SAR data was consistent with the proposed binding pose in a DAGLα homology model. Altogether our results may guide the design of future DAGLα inhibitors as leads for molecular therapies to treat neuroinflammation, obesity and related metabolic disorders.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Homeobox C9 suppresses Beclin1-mediated autophagy in glioblastoma by directly inhibiting the transcription of death-associated protein kinase 1

Authors: Xuan, F; Huang, M; Liu, W; Ding, H; Yang, L; Cui, H (2015) HERO ID: 3044599

[Less] BACKGROUND: The transcription factor homeobox C9 (HOXC9) plays a crucial role in developmental . . . [More] BACKGROUND: The transcription factor homeobox C9 (HOXC9) plays a crucial role in developmental regulatory systems, where it determines the specific positional identities of cells along the anteroposterior axis. The expression of HOXC9 has been found to be dysregulated in some cancers such as lung cancer, breast cancer, and neuroblastoma. Here, we report for the first time that HOXC9 is a novel autophagy regulator and reveal its oncogenic role in cell survival and its usefulness as a prognostic marker in glioblastoma patients.

METHODS: Kaplan-Meier analysis was performed to evaluate the possible prognostic value of HOXC9 in glioblastoma. Growth curve assays, subcutaneous, and orthotopic implantations were used to analyze cell viability and tumor formation, respectively. Luciferase and chromatin immunoprecipitation assays were employed to explore the mechanisms involved in the association between HOXC9 and its downstream effector, death-associated protein kinase 1 (DAPK1).

RESULTS: High expression of HOXC9 was found to be an indicator of a poor prognosis in glioblastoma. HOXC9 knockdown resulted in a significant reduction of cell viability, migration, invasion, and tumorigenicity and a marked increase in autophagy. During the autophagy process, HOXC9 inhibited DAPK1 transcription by directly binding to its promoter. The downregulation of HOXC9 releases its transcriptional inhibition of DAPK1, resulting in the activation of the DAPK1-Beclin1 pathway, which induces autophagy in glioblastoma cells.

CONCLUSIONS: Collectively, our data indicate that HOXC9 is an oncogene in glioblastoma. We have revealed its role in the control of autophagy, and we suggest that HOXC9 is a novel and promising therapeutic target.

Journal Article
Journal Article

Phenotypic variability related to C9orf72 mutation in a large Sardinian kindred

Authors: Floris, G; Borghero, G; Di Stefano, F; Melis, R; Puddu, R; Fadda, L; Murru, MR; Corongiu, D; Cuccu, S; Tranquilli, S; Cannas, A; Marrosu, MG; Chiò, A; Marrosu, F (2015) HERO ID: 3044601

[Less] We investigated intrafamilial phenotypic variability in carriers of the C9orf72 mutation, analysing . . . [More] We investigated intrafamilial phenotypic variability in carriers of the C9orf72 mutation, analysing clinical, neuropsychological and imaging characteristics of various members from a large Sardinian kindred with FTD or ALS. We compared these with those of C9 + patients in our ALS and FTD cohorts. Results showed that three patients carried the C9orf72 mutation: two with ALS and one with FTD and Parkinsonism. C9 + patients in our bvFTD Sardinian cohort had a higher frequency of Parkinsonism than non-mutated patients (75% vs. 36.3%, p <0.02). Parkinsonism was present in 2.7% of our ALS cohort and 3.3% of the C9 + patients. The prevalence of Parkinsonism in C9 + patients in the bvFTD and ALS cohorts showed a statistically significant difference (p <0.006). In conclusion, Parkinsonism was frequently associated with FTD but not ALS in a large Sardinian family, a finding reflected in the wider C9orf72 associated Sardinian ALS and FTD populations.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Transmembrane transporter expression regulated by the glucosylceramide pathway in Cryptococcus neoformans

Authors: Singh, A; Rella, A; Schwacke, J; Vacchi-Suzzi, C; Luberto, C; Del Poeta, M (2015) HERO ID: 3044602

[Less] BACKGROUND: The sphingolipid glucosylceramide (GlcCer) and factors involved in the . . . [More] BACKGROUND: The sphingolipid glucosylceramide (GlcCer) and factors involved in the fungal GlcCer pathways were shown earlier to be an integral part of fungal virulence, especially in fungal replication at 37 °C, in neutral/alkaline pH and 5 % CO2 environments (e.g. alveolar spaces). Two mutants, ∆gcs 1 lacking glucosylceramide synthase 1 gene (GCS1) which catalyzes the formation of sphingolipid GlcCer from the C9-methyl ceramide and ∆smt1 lacking sphingolipid C9 methyltransferase gene (SMT1), which adds a methyl group to position nine of the sphingosine backbone of ceramide, of this pathway were attenuated in virulence and have a growth defect at the above-mentioned conditions. These mutants with either no or structurally modified GlcCer located on the cell-membrane have reduced membrane rigidity, which may have altered not only the physical location of membrane proteins but also their expression, as the pathogen's mode of adaptation to changing need. Importantly, pathogens are known to adapt themselves to the changing host environments by altering their patterns of gene expression.

RESULTS: By transcriptional analysis of gene expression, we identified six genes whose expression was changed from their wild-type counterpart grown in the same conditions, i.e. they became either down regulated or up regulated in these two mutants. The microarray data was validated by real-time PCR, which confirmed their fold change in gene expression. All the six genes we identified, viz siderochrome-iron transporter (CNAG_02083), monosaccharide transporter (CNAG_05340), glucose transporter (CNAG_03772), membrane protein (CNAG_03912), membrane transport protein (CNAG_00539), and sugar transporter (CNAG_06963), are membrane-localized and have significantly altered gene expression levels. Therefore, we hypothesize that these genes function either independently or in tandem with a structurally modified cell wall/plasma membrane resulting from the modifications of the GlcCer pathway and thus possibly disrupt transmembrane signaling complex, which in turn contributes to cryptococcal osmotic, pH, ion homeostasis and its pathobiology.

CONCLUSION: Six genes identified from gene expression microarrays by gene set enrichment analysis and validated by RT-PCR, are membrane located and associated with the growth defect at neutral-alkaline pH due to the absence and or presence of a structurally modified GlcCer. They may be involved in the transmembrane signaling network in Cryptococcus neoformans, and therefore the pathobiology of the fungus in these conditions.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Critical Role and Therapeutic Control of the Lectin Pathway of Complement Activation in an Abortion-Prone Mouse Mating

Authors: Petitbarat, M; Durigutto, P; Macor, P; Bulla, R; Palmioli, A; Bernardi, A; De Simoni, MG; Ledee, N; Chaouat, G; Tedesco, F (2015) HERO ID: 3044605

[Less] The abortion-prone mating combination CBA/J × DBA/2 has been recognized as a model of preeclampsia, . . . [More] The abortion-prone mating combination CBA/J × DBA/2 has been recognized as a model of preeclampsia, and complement activation has been implicated in the high rate of pregnancy loss observed in CBA/J mice. We have analyzed the implantation sites collected from DBA/2-mated CBA/J mice for the deposition of the complement recognition molecules using CBA/J mated with BALB/c mice as a control group. MBL-A was observed in the implantation sites of CBA/J × DBA/2 combination in the absence of MBL-C and was undetectable in BALB/c-mated CBA/J mice. Conversely, C1q was present in both mating combinations. Searching for other complement components localized at the implantation sites of CBA/J × DBA/2, we found C4 and C3, but we failed to reveal C1r. These data suggest that complement is activated through the lectin pathway and proceeds to completion of the activation sequence as revealed by C9 deposition. MBL-A was detected as early as 3.5 d of pregnancy, and MBL-A deficiency prevented pregnancy loss in the abortion-prone mating combination. The contribution of the terminal complex to miscarriage was supported by the finding that pregnancy failure was largely inhibited by the administration of neutralizing Ab to C5. Treatment of DBA/2-mated CBA/J mice with Polyman2 that binds to MBL-A with high affinity proved to be highly effective in controlling the activation of the lectin pathway and in preventing fetal loss.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

A multifunctional role of trialkylbenzenes for the preparation of aqueous colloidal mesostructured/mesoporous silica nanoparticles with controlled pore size, particle diameter, and morphology

Authors: Yamada, H; Ujiie, H; Urata, C; Yamamoto, E; Yamauchi, Y; Kuroda, K (2015) HERO ID: 3044609

[Less] Both the pore size and particle diameter of aqueous colloidal mesostructured/mesoporous silica nanoparticles . . . [More] Both the pore size and particle diameter of aqueous colloidal mesostructured/mesoporous silica nanoparticles (CMSS/CMPS) derived from tetrapropoxysilane were effectively and easily controlled by the addition of trialkylbenzenes (TAB). Aqueous highly dispersed CMPS with large pores were successfully obtained through removal of surfactants and TAB by a dialysis process. The pore size (from 4 nm to 8 nm) and particle diameter (from 50 nm to 380 nm) were more effectively enlarged by the addition of 1,3,5-triisopropylbenzene (TIPB) than 1,3,5-trimethylbenzene (TMB), and the enlargement did not cause the variation of the mesostructure and particle morphology. The larger molecular size and higher hydrophobicity of TIPB than TMB induce the incorporation of TIPB into micelles without the structural change. When TMB was used as TAB, the pore size of CMSS was also enlarged while the mesostructure and particle morphology were varied. Interestingly, when tetramethoxysilane and TIPB were used, CMSS with a very small particle diameter (20 nm) with concave surfaces and large mesopores were obtained, which may strongly be related to the initial nucleation of CMSS. A judicious choice of TAB and Si sources is quite important to control the mesostructure, size of mesopores, particle diameter, and morphology.

Journal Article
Journal Article

The distant siblings - a phylogenomic roadmap illuminates the origins of extant diversity in fungal aromatic polyketide biosynthesis

Authors: Koczyk, G; Dawidziuk, A; Popiel, D (2015) HERO ID: 3044610

[Less] In recent years, the influx of newly sequenced fungal genomes has enabled sampling of secondary metabolite . . . [More] In recent years, the influx of newly sequenced fungal genomes has enabled sampling of secondary metabolite biosynthesis on an unprecedented scale. However, explanations of extant diversity which take into account both large-scale phylogeny reconstructions and knowledge gained from multiple genome projects are still lacking.We analysed the evolutionary sources of genetic diversity in aromatic polyketide biosynthesis in over a hundred model fungal genomes. By reconciling the history of over four hundred non-reducing polyketide synthases with corresponding species history, we demonstrate that extant fungal NR-PKSs are clades of distant siblings, originating from a burst of duplications in early Pezizomycotina and thinned by extensive losses.The capability of higher fungi to biosynthesise the simplest precursor molecule (orsellinic acid) is highlighted as an ancestral trait underlying biosynthesis of aromatic compounds. This base activity was modified during early evolution of filamentous fungi, towards divergent reaction schemes associated with biosynthesis of e.g. aflatoxins and fusarubins (C4-C9 cyclisation) or various anthraquinone derivatives (C6-C11 cyclisation). The functional plasticity is further shown to have been supplemented by modularisation of domain architecture into discrete pieces (conserved splice junctions within product template domain), as well as tight linkage of key accessory enzyme families and divergence in employed transcriptional factors.While the majority of discord between species and gene history is explained by ancient duplications, this landscape has been altered by more recent duplications, as well as multiple Horizontal Gene Transfers. The 25 detected transfers include previously undescribed events leading to emergence of e.g. fusarubin biosynthesis in Fusarium genus.Both the underlying data and the results of present analysis (including alternative scenarios revealed by sampling multiple reconciliation optima) are maintained as a freely available web-based resource: http://cropnet.pl/metasites/sekmet/nrpks_2014.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Heterobimetallic Zeolite, InV-ZSM-5, Enables Efficient Conversion of Biomass Derived Ethanol to Renewable Hydrocarbons

Authors: Narula, CK; Li, Z; Casbeer, EM; Geiger, RA; Moses-Debusk, M; Keller, M; Buchanan, MV; Davison, BH (2015) Scientific Reports 5:16039. HERO ID: 3044612

[Less] Direct catalytic conversion of ethanol to hydrocarbon blend-stock can increase biofuels use in current . . . [More] Direct catalytic conversion of ethanol to hydrocarbon blend-stock can increase biofuels use in current vehicles beyond the ethanol blend-wall of 10-15%. Literature reports describe quantitative conversion of ethanol over zeolite catalysts but high C2 hydrocarbon formation renders this approach unsuitable for commercialization. Furthermore, the prior mechanistic studies suggested that ethanol conversion involves endothermic dehydration step. Here, we report the complete conversion of ethanol to hydrocarbons over InV-ZSM-5 without added hydrogen and which produces lower C2 (<13%) as compared to that over H-ZSM-5. Experiments with C2H5OD and in situ DRIFT suggest that most of the products come from the hydrocarbon pool type mechanism and dehydration step is not necessary. Thus, our method of direct conversion of ethanol offers a pathway to produce suitable hydrocarbon blend-stock that may be blended at a refinery to produce fuels such as gasoline, diesel, JP-8, and jet fuel, or produce commodity chemicals such as BTX.