Discovery and redescription of type material of Nausithoe simplex (Kirkpatrick, 1890), comb. nov (Cnidaria: Scyphozoa: Coronatae: Nausithoidae) from the North Atlantic

With discovery and examination of type specimens in the Natural History Museum, London, UK, we reassign Stephanoscyphistoma simplex (Kirkpatrick, 1890) to the genus Nausithoe Kolliker, 1853, as Nausithoe simplex, comb. nov., and designate a lectotype for the species. Use of morphometric measurements is considered important in coronate systematics, but key features also include the unique whorl of internal cusps and the shape of these cusps. All previous records of N. simplex must be re-evaluated, taking into consideration the morphology of these internal cusps.

Discovery and cross-section measurement of neutron-rich isotopes in the element range from neodymium to platinum with the FRS

Using the high-resolution performance of the fragment separator FRS at GSI we have discovered 60 new neutron-rich isotopes in the atomic number range of 60 <= Z <= 78. The new isotopes were unambiguously identified in reactions with a U-238 beam impinging on a Be target at 1 GeV/nucleon. The production cross-section for the new isotopes have been measured down to the pico-barn level and compared with predictions of different model calculations. For elements above hafnium fragmentation is the dominant reaction mechanism which creates the new isotopes, whereas fission plays a dominant role for the production of the new isotopes up to thulium. (C) 2012 Elsevier B.V. All rights reserved.

Pharmacokinetic properties and in silico ADME modeling in drug discovery

The discovery and development of a new drug are time-consuming, difficult and expensive. This complex process has evolved from classical methods into an integration of modern technologies and innovative strategies addressed to the design of new chemical entities to treat a variety of diseases. The development of new drug candidates is often limited by initial compounds lacking reasonable chemical and biological properties for further lead optimization. Huge libraries of compounds are frequently selected for biological screening using a variety of techniques and standard models to assess potency, affinity and selectivity. In this context, it is very important to study the pharmacokinetic profile of the compounds under investigation. Recent advances have been made in the collection of data and the development of models to assess and predict pharmacokinetic properties (ADME - absorption, distribution, metabolism and excretion) of bioactive compounds in the early stages of drug discovery projects. This paper provides a brief perspective on the evolution of in silico ADME tools, addressing challenges, limitations, and opportunities in medicinal chemistry.

How wild bearded capuchin monkeys select stones and nuts to minimize the number of strikes per nut cracked

Wild bearded capuchin monkeys, Cebus libidinosus, use stone tools to crack palm nuts to obtain the kernel. In five experiments, we gave 10 monkeys from one wild group of bearded capuchins a choice of two nuts differing in resistance and size and/or two manufactured stones of the same shape, volume and composition but different mass. Monkeys consistently selected the nut that was easier to crack and the heavier stone. When choosing between two stones differing in mass by a ratio of 1.3:1, monkeys frequently touched the stones or tapped them with their fingers or with a nut. They showed these behaviours more frequently before making their first selection of a stone than afterward. These results suggest that capuchins discriminate between nuts and between stones, selecting materials that allow them to crack nuts with fewer strikes, and generate exploratory behaviours to discriminate stones of varying mass. In the final experiment, humans effectively discriminated the mass of stones using the same tapping and handling behaviours as capuchins. Capuchins explore objects in ways that allow them to perceive invariant properties (e.g. mass) of objects, enabling selection of objects for specific uses. We predict that species that use tools will generate behaviours that reveal invariant properties of objects such as mass; species that do not use tools are less likely to explore objects in this way. The precision with which individuals can judge invariant properties may differ considerably, and this also should predict prevalence of tool use across species. (C) 2010 The Association for the Study of Animal Behaviour. Published by Elsevier Ltd. All rights reserved.

Two series of new semisynthetic triterpene derivatives: differences in anti-malarial activity, cytotoxicity and mechanism of action

Background The discovery and development of anti-malarial compounds of plant origin and semisynthetic derivatives thereof, such as quinine (QN) and chloroquine (CQ), has highlighted the importance of these compounds in the treatment of malaria. Ursolic acid analogues bearing an acetyl group at C-3 have demonstrated significant anti-malarial activity. With this in mind, two new series of betulinic acid (BA) and ursolic acid (UA) derivatives with ester groups at C-3 were synthesized in an attempt to improve anti-malarial activity, reduce cytotoxicity, and search for new targets. In vitro activity against CQ-sensitive Plasmodium falciparum 3D7 and an evaluation of cytotoxicity in a mammalian cell line (HEK293T) are reported. Furthermore, two possible mechanisms of action of anti-malarial compounds have been evaluated: effects on mitochondrial membrane potential (ΔΨm) and inhibition of β-haematin formation. Results Among the 18 derivatives synthesized, those having shorter side chains were most effective against CQ-sensitive P. falciparum 3D7, and were non-cytotoxic. These derivatives were three to five times more active than BA and UA. A DiOC6(3) ΔΨm assay showed that mitochondria are not involved in their mechanism of action. Inhibition of β-haematin formation by the active derivatives was weaker than with CQ. Compounds of the BA series were generally more active against P. falciparum 3D7 than those of the UA series. Conclusions Three new anti-malarial prototypes were obtained from natural sources through an easy and relatively inexpensive synthesis. They represent an alternative for new lead compounds for anti-malarial chemotherapy.