The aminopeptidase inhibitor CHR-2863 is an orally bioavailable inhibitor of murine malaria

Malaria remains a significant risk in many areas of the world, with resistance to the current antimalarial pharmacopeia an everincreasing problem. The M1 alanine aminopeptidase (PfM1AAP) and M17 leucine aminopeptidase (PfM17LAP) are believed to play a role in the terminal stages of digestion of host hemoglobin and thereby generate a pool of free amino acids that are essential for parasite growth and development. Here, we show that an orally bioavailable aminopeptidase inhibitor, CHR-2863, is efficacious against murine malaria

Theoretical investigations of the cyanogen anion

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Theoretical investigations of the cyanogen anion

Large ab initio calculations are performed on neutral cyanogen (C2N2) and its negatively charged ion (C2 N2 -). Four stable isomers are found on the lowest doublet potential energy surface of the anion: trans NCCN-over(X, ∼) 2Bu, trans CNCN-over(X, ∼) 2A′, trans CNNC-over(X, ∼) 2Bu and trans NNCC-over(X, ∼) 2A′. A set of spectroscopic data is derived for them at the RCCSD(T)/aug cc-pVTZ level of theory. The vertical and the adiabatic electron affinities are also deduced. High level ab initio calculations show that no metastable electronically excited states may exist either in the doublet or in the quartet states manifolds of C2 N2 - species. © 2008 Elsevier B.V. All rights reserved.One of the authors (M.N.) thanks the Swedish International Development Agency (SIDA) and the Abdus Salam ICTP (Trieste, Italy), for their financial support during his visit to the ICTP where part of this work was done, under its associateship scheme. MLS wants to thanks the MEC of Spain for the Grant AYA2005-00702 and the CESGA computational center.Peer Reviewe

Hypervirial and Hellmann-Feynman theorems applied to the calculation of energy levels for relativistic particles

The nonrelativistic hypervirial Hellmann-Feynman method developed recently is extended to deal with relativistic particles bound in a spherically symmetric potential. A simple analytical procedure for calculating correction terms of arbitrary high orders is derived. Numerical results obtained through a study of the screened Coulomb potential enable us to illustrate the improvements of our procedure over the previous approaches

New U–Pb zircon ages of Nyong Complex meta‐plutonites: Implications for the Eburnean/Trans‐Amazonian Orogeny in southwestern Cameroon (Central Africa)

New LA–ICP–MS U–Pb zircon ages from the Nyong Complex of southwestern Cameroon—a part of the West Central African Fold Belt—trace Late Mesoarchean (∼2,850 Ma), Middle Palaeoproterozoic (∼2,080 Ma), and Neoproterozoic (∼605 Ma) events: Two meta‐syenites and the protolith of an amphibolite are Late Mesoarchean; two meta‐granodiorites are Middle Palaeoproterozoic; the amphibolite may have recrystallized in the Middle Palaeoproterozoic; all rocks are overprinted by the Neoproterozoic event. Integration with published data shows that our amphibolite sample has one of the oldest amphibolite‐protolith ages (∼2,810 Ma) reported so far. It shares the Middle Palaeoproterozoic metamorphism/recrystallization with other, previously dated amphibolites. An earlier reported metamorphic zircon age (∼2,090 Ma) from eclogite is somewhat older than the regional Middle Palaeoproterozoic metamorphism/recrystallization ages (∼2,040 Ma) reported from amphibolites. Thus, the eclogite–amphibolite ages may date an exhumation process. A published charnockite age, interpreted as an Early Mesoarchean crystallization age, is older than the Late Mesoarchean meta‐syenite and amphibolite‐protolith dates; its Middle Palaeoproterozoic metamorphism/recrystallization age, however, is identical with the meta‐granodiorites and amphibolites. The Neoproterozoic ages demonstrate the regional overprint of the Nyong Complex during this period. Integration of the Nyong Complex ages with published ones from the entire West Central African Fold Belt, and comparison with those from West Africa and South America, support their common origin from the Palaeoproterozoic collision between the Archean Congo and São Francisco shields.(a) South America–Africa fit, showing shields of western Gondwana (modified after Neves et al., 2006). (b) Geological sketch of Cameroon, showing its Archean, Paleo‐, and Neoproterozoic basement and the Cretaceous‐Cenozoic volcano‐sedimentary cover (modified after Castaing et al., 1994; Ngako, Affaton, Nnangue, & Njanko, 2003; Owona, Mvondo Ondoa & Ekodeck, 2013). (c) Geology of the Nyong Complex and related U‐Pb zircon ages. Abbreviations: NEFB – North Equatorial Fold belt, OC – Oubanguide Complex. Published studies: 1 – Toteu et al. (1994), 2 – Lerouge et al. (2006), 3 – Loose & Schenk (2018), 4 – Nkoumbou et al. (2015), and * – present study. (d) Normalized age probability diagrams summarizing the new and published U‐Th‐Pb ages from the West Central African fold belt (including the Nyong Complex), and those from the South American and West African equivalents. Abbreviations: CS – Congo Shield, KS – Kalahari Shield, SFS – São Francisco Shield, TS – Tanzania Shield, WAS – West African Shield. imageGerman Academic Exchange Service http://dx.doi.org/10.13039/50110000165