Terretonin N: A New Meroterpenoid from Nocardiopsis sp.

Hamed A, Abdel-Razek AS, Frese M, et al. Terretonin N: A New Meroterpenoid from Nocardiopsis sp. Molecules. 2018;23(2): 299.Terretonin N (1), a new highly oxygenated and unique tetracyclic 6-hydroxymeroterpenoid, was isolated together with seven known compounds from the ethyl acetate extract of a solid-state fermented culture of Nocardiopsis sp. Their structures were elucidated by spectroscopic analysis. The structure and absolute configuration of 1 were unambiguously determined by X-ray crystallography. The isolation and taxonomic characterization of Nocardiopsis sp. is reported. The antimicrobial activity and cytotoxicity of the strain extract and compound 1 were studied using different microorganisms and a cervix carcinoma cell line, respectively

Crystalline anions based on classical N‐heterocyclic carbenes

Herein, the first stable anions K[SIPrBp] (4 a‐K) and K[IPrBp] (4 b‐K) (SIPrBp=BpC{N(Dipp)CH2}2, IPrBp=BpC{N(Dipp)CH}2; Bp=4‐PhC6H4; Dipp=2,6‐iPr2C6H3) derived from classical N‐heterocyclic carbenes (NHCs) (i.e. SIPr and IPr) have been isolated as violet crystalline solids. 4 a‐K and 4 b‐K are prepared by KC8 reduction of the neutral radicals [SIPrBp] (3 a) and [IPrBp] (3 b), respectively. The radicals 3 a and 3 b as well as [Me‐IPrBp] 3 c (Me‐IPrBp=BpC{N(Dipp)CMe}2) are accessible as crystalline solids on treatment of the respective 1,3‐imidazoli(ni)um bromides (SIPrBp)Br (2 a), (IPrBp)Br (2 b), and (Me-IPrBp)Br (2 c) with KC8. The cyclic voltammograms of 2 a-2 c exhibit two one‐electron reversible redox processes in -0.5 to -2.5 V region that correspond to the radicals 3 a-3 c and the anions (4 a-4 c)-. Computational calculations suggest a closed‐shell singlet ground state for (4 a-4 c)- with the singlet‐triplet energy gap of 17-24 kcal mol-1.Deutsche ForschungsgemeinschaftProjekt DEA

Kristalline Anionen auf Basis klassischer N‐heterocyclischer Carbene

Die ersten stabilen Anionen K[SIPrBp] (4 a-K) und K[IPrBp] (4 b-K) (SIPrBp=BpC{N(Dipp)CH2}2, IPrBp=BpC{N(Dipp)CH}2; Bp=4-PhC6H4; Dipp=2,6-iPr2C6H3), die von klassischen N-heterocyclischen Carbenen (NHCs) abgeleitet sind (d. h. SIPr und IPr), wurden als violette kristalline Feststoffe isoliert. 4 a-K und 4 b-K wurden durch die Reduktion der neutralen Radikale [SIPrBp] (3 a) bzw. [IPrBp] (3 b) mit KC8 hergestellt. Die Radikale 3 a und 3 b sowie [Me-IPrBp] (3 c) (Me-IPrBp=BpC{N(Dipp)CMe}2) liegen als kristalline Feststoffe vor, wenn die entsprechenden 1,3-Imidazoli(ni)umbromide (SIPrBp)Br (2 a), (IPrBp)Br (2 b) und (Me-IPrBp)Br (2 c) mit KC8 umgesetzt werden. Die Cyclovoltammogramme von 2 a-2 c zeigen zwei reversible Ein-Elektronen-Redoxprozesse im Bereich von -0.5 bis -2.5 V, die den Radikalen 3 a-3 c und den Anionen (4 a-4 c)- entsprechen. Quantenchemische Berechnungen deuten auf einen geschlossenschaligen Singulett-Grundzustand für (4 a-4 c)- mit einer Singulett-Triplett-Energielücke von 17-24 kcal mol-1 hin.Deutsche ForschungsgemeinschaftProjekt DEA

The diagnostic value of ultrasonography-derived edema of the temporal artery wall in giant cell arteritis: a second meta-analysis

<p>Abstract</p> <p>Background</p> <p>Ultrasonography of temporal arteries is not commonly used in the approach of patients with suspected giant cell arteritis (GCA) in clinical practice. A meta-analysis of primary studies available through April 2004 concluded that ultrasonography could indeed be helpful in diagnosing GCA. We specifically re-examined the diagnostic value of the ultrasonography-derived halo sign, a dark hypoechoic circumferential thickening around the artery lumen, indicating vasculitic wall edema, in GCA.</p> <p>Methods</p> <p>Original, prospective studies in patients with suspected GCA that examined ultrasonography findings of temporal arteries using the ACR 1990 classification criteria for GCA as reference standard, published through 2009, were identified. Only eight studies involving 575 patients, 204 of whom received the final diagnosis of GCA, fulfilled technical quality criteria for ultrasound. Weighted sensitivity and specificity estimates of the halo sign were assessed, their possible heterogeneity was investigated and pooled diagnostic odds ratio was determined.</p> <p>Results</p> <p>Unilateral halo sign achieved an overall sensitivity of 68% (95% CI, 0.61-0.74) and specificity of 91% (95% CI, 0.88-0.94) for GCA. The values of inconsistency coefficient (I²) of both sensitivity and specificity of the halo sign, showed significant heterogeneity concerning the results between studies. Pooled diagnostic odds ratio, expressing how much greater the odds of having GCA are for patients with halo sign than for those without, was 34 (95% CI, 8.21-138.23). Diagnostic odds ratio was further increased to 65 (95% CI, 17.86-236.82) when bilateral halo signs were present (sensitivity/specificity of 43% and 100%, respectively). In both cases, it was found that DOR was constant across studies.</p> <p>Conclusion</p> <p>Temporal artery edema demonstrated as halo sign should be always looked for in ultrasonography when GCA is suspected. Providing that currently accepted technical quality criteria are fulfilled, halo sign's sensitivity and specificity are comparable to those of autoantibodies used as diagnostic tests in rheumatology. Validation of revised GCA classification criteria which will include the halo sign may be warranted.</p

Temporal and structural genetic variation in reindeer (Rangifer tarandus) associated with the pastoral transition in Northwestern Siberia

Funding Information NordForsk. Grant Number: 76915 ERC Advanced Grant. Grant Numbers: 295458, ESRC ES/, M011054/1 JPI HUMANOR ERC Starting GrantPeer reviewedPublisher PD

The anthropology of extraction: critical perspectives on the resource curse

Attempts to address the resource curse remain focussed on revenue management, seeking technical solutions to political problems over examinations of relations of power. In this paper, we provide a review of the contribution anthropological research has made over the past decade to understanding the dynamic interplay of social relations, economic interests and struggles over power at stake in the political economy of extraction. In doing so, we show how the constellation of subaltern and elite agency at work within processes of resource extraction is vital in order to confront the complexities, incompatibilities, and inequities in the exploitation of mineral resources

Unorthodoxy in legislation: The Hungarian experience

This paper deals with legal unorthodoxy. The main idea is to study the so-called unorthodox taxes Hungary has adopted in recent years. The study of unorthodox taxes will be preceded by a more general discussion of how law is made under unorthodoxy, and what are the special features of unorthodox legal policy. Unorthodoxy challenges equality before the law and is critical towards mass democracies. It also raises doubts on the operability of the rule of law, relying on personal skills, or loyalty, rather than on impersonal mechanisms arising from checks and balances as developed by the division of political power. Besides, for lack of legal suppositions, legislation suffers from casuistry and regulatory capture

Connecting Planetary Composition with Formation

The rapid advances in observations of the different populations of exoplanets, the characterization of their host stars and the links to the properties of their planetary systems, the detailed studies of protoplanetary disks, and the experimental study of the interiors and composition of the massive planets in our solar system provide a firm basis for the next big question in planet formation theory. How do the elemental and chemical compositions of planets connect with their formation? The answer to this requires that the various pieces of planet formation theory be linked together in an end-to-end picture that is capable of addressing these large data sets. In this review, we discuss the critical elements of such a picture and how they affect the chemical and elemental make up of forming planets. Important issues here include the initial state of forming and evolving disks, chemical and dust processes within them, the migration of planets and the importance of planet traps, the nature of angular momentum transport processes involving turbulence and/or MHD disk winds, planet formation theory, and advanced treatments of disk astrochemistry. All of these issues affect, and are affected by the chemistry of disks which is driven by X-ray ionization of the host stars. We discuss how these processes lead to a coherent end-to-end model and how this may address the basic question.Comment: Invited review, accepted for publication in the 'Handbook of Exoplanets', eds. H.J. Deeg and J.A. Belmonte, Springer (2018). 46 pages, 10 figure

Fungicide-Driven Evolution and Molecular Basis of Multidrug Resistance in Field Populations of the Grey Mould Fungus Botrytis cinerea

The grey mould fungus Botrytis cinerea causes losses of commercially important fruits, vegetables and ornamentals worldwide. Fungicide treatments are effective for disease control, but bear the risk of resistance development. The major resistance mechanism in fungi is target protein modification resulting in reduced drug binding. Multiple drug resistance (MDR) caused by increased efflux activity is common in human pathogenic microbes, but rarely described for plant pathogens. Annual monitoring for fungicide resistance in field isolates from fungicide-treated vineyards in France and Germany revealed a rapidly increasing appearance of B. cinerea field populations with three distinct MDR phenotypes. All MDR strains showed increased fungicide efflux activity and overexpression of efflux transporter genes. Similar to clinical MDR isolates of Candida yeasts that are due to transcription factor mutations, all MDR1 strains were shown to harbor activating mutations in a transcription factor (Mrr1) that controls the gene encoding ABC transporter AtrB. MDR2 strains had undergone a unique rearrangement in the promoter region of the major facilitator superfamily transporter gene mfsM2, induced by insertion of a retrotransposon-derived sequence. MDR2 strains carrying the same rearranged mfsM2 allele have probably migrated from French to German wine-growing regions. The roles of atrB, mrr1 and mfsM2 were proven by the phenotypes of knock-out and overexpression mutants. As confirmed by sexual crosses, combinations of mrr1 and mfsM2 mutations lead to MDR3 strains with higher broad-spectrum resistance. An MDR3 strain was shown in field experiments to be selected against sensitive strains by fungicide treatments. Our data document for the first time the rising prevalence, spread and molecular basis of MDR populations in a major plant pathogen in agricultural environments. These populations will increase the risk of grey mould rot and hamper the effectiveness of current strategies for fungicide resistance management

Mutagenesis and Functional Studies with Succinate Dehydrogenase Inhibitors in the Wheat Pathogen Mycosphaerella graminicola

A range of novel carboxamide fungicides, inhibitors of the succinate dehydrogenase enzyme (SDH, EC 1.3.5.1) is currently being introduced to the crop protection market. The aim of this study was to explore the impact of structurally distinct carboxamides on target site resistance development and to assess possible impact on fitness