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A decade of progress in understanding the structural basis of protein synthesis

The key reaction of protein synthesis, peptidyl transfer, is catalysed in all living organisms by the ribosome - an advanced and highly efficient molecular machine. During the last decade extensive X-ray crystallographic and NMR studies of the three-dimensional structure of ribosomal proteins, ribosomal RNA components and their complexes with ribosomal proteins, and of several translation factors

Effect of nedocromil sodium on non-adrenergic, non-cholinergic neural responses in guinea pig bronchi in vitro

OBJECTIVE: Nedocromil sodium (nedocromil) improves the clinical condition of asthmatic subjects but its mechanism of action is not fully understood. This study aimed to determine whether nedocromil alters the ability of contractile and relaxant non-adrenergic, non-cholinergic neural (NANC) responses to stabilise tone by inhibiting or potentiating these responses in bronchial smooth muscle and, if

GBV-C/HGV infection in hepatitis C virus-infected deferred Swedish blood donors

Sera from 62 hepatitis C virus (HCV)-infected Swedish blood donors were tested by a nested polymerase chain reaction using primers targeting the 5'-noncoding region of the GB virus-C/hepatitis G (GBV-C/HGV) genome and an enzyme-linked immunosorbent assay that detects antibodies to the envelope protein E2 of GBV-C/HGV (anti-E2). Fourteen (22%) and 21 (34%) of the 62 blood donors were found to be GB

Feeding, reproduction and toxin accumulation by the copepods Acartia bifilosa and Eurytemora affinis in the presence of the toxic cyanobacterium Nodularia spumigena

Feeding, reproduction and accumulation of cyanobacterial toxins by the calanoid copepods Acartia bifilosa and Eurytemora affinis were studied during a cruise in the northern Baltic Sea. The experiments were carried out using both mixtures of natural plankton communities, mixtures containing the toxic Nodularia spumigena, and diets containing only the toxic cyanobacterium. Both copepod species had

Environmental factors influencing growth of and exopolysaccharide formation by Pediococcus parvulus 2.6

Natural exopolysaccharides (EPSs) from food-grade lactic acid bacteria have potential for development and exploitation as food additives and functional food ingredients with both health and economic benefits. In this study, we have examined the physiological capacity of EPS production in Pediococcus parvulus 2.6. EPS formation by P. parvulus 2.6 was found to be linked to biomass yields, provided t

Open reduction and internal fixation compared to closed reduction and external fixation in distal radial fractures A randomized study of 50 patients

Background and purpose In unstable distal radial fractures that are impossible to reduce or to maintain in reduced position, the treatment of choice is operation. The type of operation and the choice of implant, however, is a matter of discussion. Our aim was to investigate whether open reduction and internal fixation would produce a better result than traditional external fixation. Methods 50 pat

The apparent plasticizing effect of polyethylene glycol (PEG) on the crystallinity of spray dried lactose/PEG composites

Aqueous solutions of lactose and polyethylene glycol (PEG) were spray dried in a Buchi Model 191 spray dryer with the aim to investigate the effect of PEG on the crystallinity of the composite. A PEG concentration of 10.7% by weight of solids was studied for PEG 200, 600, 1500, 4000 and 8000. For PEG 200 and 4000 additional concentrations from 1.5-19.3% to 1.5-32.4%, respectively, were investigate

Trisomy 19 as the sole chromosomal abnormality in proliferative chronic myelomonocytic leukemia

Distinct morphologic and clinical features associated with specific chromosomal abnormalities have been described in subgroups of myelodysplastic syndromes (MDS), which often are losses or gains and only rarely translocations. Among 103 consecutive MDS patients diagnosed and karyotyped at the Albert-Ludwigs University of Freiburg (ALU) between 1993 and 1999, two chronic myelomonocytic leukemias (C

Marine-derived dinoflagellates in Antarctic saline lakes: annual dynamics and community composition

The saline lakes of the Vestfold Hills in Antarctica offer a remarkable natural laboratory where the adaptation of planktonic protists to a range of evolving physiochemical conditions can be investigated. This study illustrates how an ancestral marine community has undergone radical simplification leaving a small number of well-adapted species. Our objective was to investigate the species composit

Biology

The hottest developments in the fields of cancer research, neuroscience, genomics and proteomics, anti-virals and more, with a pick of the key research papers in these areas.

A geometric approach to Boolean matrix multiplication

For a Boolean matrix D, let r(D) be the minimum number of rectangles sufficient to cover exactly the rectilinear region formed by the 1-entries in D. Next, let m(D) be the minimum of the number of 0-entries and the number of 1-entries in D. Suppose that the rectilinear regions formed by the 1-entries in two n x n Boolean matrices A and B totally with q edges are given. We show that in time (O) ove

Are growth forms consistent predictors of leaf litter quality and decomposability across peatlands along a latitudinal gradient?

Plant growth forms are widely used to predict the effects of environmental changes, such as climate warming and increased nitrogen deposition, on plant communities, and the consequences of species shifts for carbon and nutrient cycling. We investigated whether the relationship between growth forms and patterns in litter quality and decomposition are independent of environmental conditions and whet

Photoelectron spectroscopy study of free potassium clusters: Core-level lines and plasmon satellites

Free neutral potassium clusters of two different mean sizes were produced using a gas aggregation source. The K 3p core level was probed by means of synchrotron radiation based photoelectron spectroscopy. The absolute binding energy and the intensity ratio of the surface and bulk spectral features were used to obtain independent estimates of the cluster size. Plasmon satellites in core level spect

Molecular origin of time-dependent fluorescence shifts in proteins

Time-resolved fluorescence spectroscopy is used increasingly to probe molecular motions at the aqueous interfaces of biological macromolecules and membranes. By recording the time variation of the fluorescence frequency, thermal atomic fluctuations in the vicinity of the chromophore can be probed. From such fluorescence Stokes shift (FSS) experiments, it has been inferred that water motions in the

Influence of ferrocene addition to a laminar premixed propene flame: Laser diagnostics, mass spectrometry and numerical simulations

The detailed influence of ferrocene in a low-pressure, fuel-rich, laminar, premixed propene/oxygen/ argon flat flame was investigated experimentally using molecular beam sampling mass spectrometry (MBMS), laser-induced fluorescence (LIF), and compared to numerical simulations. MBMS was applied to analyze the species profiles of important intermediates in the flames with and without ferrocene dopin

Multiple interactions and the structure of beam remnants

Recent experimental data have established some of the basic features of multiple interactions in hadron-hadron collisions. The emphasis is therefore now shifting, to one of exploring more detailed aspects. Starting from a brief review of the current situation, a next-generation model is developed, wherein a detailed account is given of correlated flavour, colour, longitudinal and transverse moment