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Staphylococcus aureus is a major opportunistic and versatile pathogen. Because the bacteria rapidly evolve multi-resistances towards antibiotics, there is an urgent need to find novel targets and alternative strategies to cure bacterial infections. Here, we provide a brief overview on the knowledge acquired on S. aureus ribosomes, which is one of the major antibiotic targets. We will show that subtle differences exist between the translation at the initiation step of Gram-negative and Gram-positive bacteria although their ribosomes display a remarkable degree of resemblance. In addition, we will illustrate using specific examples the diversity of mechanisms controlling translation initiation in S. aureus that contribute to shape the expression of the virulence factors in a temporal and dynamic manner. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of our paper is to illustrate our experience with minimally invasive approaches for the treatment of cervical schwannomas. Moreover, a brief review of the literature was conducted. Methods: All data regarding patients treated for cervical schwannomas were retrospectively revised. Site, size and extension of the lesions and preoperative neurological status were obtained through re-examination of neuroimaging and clinical records. Postoperative clinical examinations and radiological images were available for all patients. The clinical course was documented using the visual analog scale (VAS), Karnofsky score (KPS) and the Klekamp-Samii score system. Results: Sixteen patients harboring cervical schwannomas were treated from 2003 to 2009. Hemilaminectomy was performed in eight cases, subtotal hemilaminectomy in four cases, interlaminar fenestration in two cases, osteoplastic hemilaminotomy and laminoplasty in one case each. Postoperative neuroimaging revealed complete removal of the lesion and no signs of spinal instability. At discharge, neurological improvement was observed in 14 patients and all patients demonstrated reduction of VAS score and improvement of KPS and Klekamp-Samii's score. Conclusions: Minimal access procedures are increasingly gaining popularity but their use is poorly described in the treatment of cervical tumors. Less invasive approaches may effectively be used instead of traditional laminectomy in the treatment of cervical tumors, especially schwannomas, providing less iatrogenic traumatism and preventing postsurgical spinal instability. Modern neuroimaging allows adequate preoperative planning and microsurgical techniques provide adequate execution of the surgical act. The procedure has to be tailored case by case considering the specific lesional features and the individual anatomical situation. [ABSTRACT FROM AUTHOR]

Summary Small non-coding RNA molecules (sRNA) are key regulators participating in complex networks, which adapt metabolism in response to environmental changes. In this issue of Molecular Microbiology, and in a related paper in Proc. Natl. Acad. Sci. USA, ) and ) report on novel sRNAs, which act as decoys to inhibit the activity of the master post-transcriptional regulatory protein Crc. Crc is a key protein involved in carbon catabolite repression that optimizes metabolism improving the adaptation of the bacteria to their diverse habitats. Crc is a novel RNA-binding protein that regulates translation of multiple target mRNAs. Two regulatory sRNAs in Pseudomonas putida mimic the natural mRNA targets of Crc and counteract the action of Crc by sequestrating the protein when catabolite repression is absent. Crc trapping by a sRNA is a mechanism reminiscent to the regulation of the repressor of secondary metabolites (RsmA) in Pseudomonas, and highlights the suitability of RNA-dependent regulation to rapidly adjust cell growth in response to environmental changes. [ABSTRACT FROM AUTHOR]

This paper introduces a newly developed specimen type, which is used to measure the critical energy release rate of tough, structural adhesives loaded in shear. This End-Loaded Shear Joint (ELSJ) specimen is loaded until a shear crack propagates through the adhesive layer. When the crack propagation is stopped, by unloading the specimen, the critical energy release rate in mode II, GIIc, can be obtained by correlating the energy dissipated during the test and the measured crack area on the fracture surface of the specimen. The paper presents the dimensions of the ELSJ specimen, the corresponding test setup and the evaluation method used to obtain GIIc. An overview of the advantages and the limitations of the new specimen type shows the need for its development and improvement when compared to some state of the art experiments. The first results of ELSJ tests are shown and discussed, using the crash-optimized structural adhesive — Henkel Terokal 5077. The experimental results presented, focus on thin adhesive layers and quasi-static test velocities. [ABSTRACT FROM AUTHOR]

The present work investigates the rate-dependent failure behaviour of structural adhesive joints loaded in mode I. Butt joint and tapered double cantilever beam (TDCB) specimens were tested at velocities ranging over more than six orders of magnitude. A rate-dependent extension of the bi-linear cohesive zone model is proposed and implemented into the finite element code LS-DYNA via an user-defined subroutine. The parameters for the implemented cohesive zone model are found directly by evaluation of experimental data. The comparison of simulations with experimental results for different specimen types and test velocities validates the proposed model. The critical energy release rate of adhesively bonded joints is usually measured in (tapered) double cantilever beam tests, and evaluated using the Irwin–Kies equation. In this paper a different evaluation method is proposed, which provides additional information on the energy dissipated during crack initiation. The results of this method agree with the results obtained using the Irwin–Kies equation. The investigations have focussed on thin adhesive layers. Parameter identification and validation have been performed using the crash-optimized adhesive Terokal 5077 from Henkel. [ABSTRACT FROM AUTHOR]

The assembly of the protein synthesis machinery occurs during translation initiation. In bacteria, this process involves the binding of messenger RNA(mRNA) start site and fMet-tRNAfMet to the ribosome, which results in the formation of the first codon-anticodon interaction and sets the reading frame for the decoding of the mRNA. This interaction takes place in the peptidyl site of the 30S ribosomal subunit and is controlled by the initiation factors IF1, IF2 and IF3 to form the 30S initiation complex. The binding of the 50S subunit and the ejection of the IFs mark the irreversible transition to the elongation phase. Visualization of these ligands on the ribosome has been achieved by cryo-electron microscopy and X-ray crystallography studies, which has helped to understand the mechanism of translation initiation at the molecular level. Conformational changes associated with different functional states provide a dynamic view of the initiation process and of its regulation. [ABSTRACT FROM AUTHOR]