Relationships between water,nutrients and productivity in Australian forests: Application to wood production and quality

The application of knowledge of water and nutrient relationships to improve forest management is discussed from an Australian perspective. The objectives of tree planting and forest management have become diverse, and there are outstanding examples of successful application of research results to forestry.Experiments seeking to explain the way water and nutrients influence growth tend to use treatments designed to ensure large differences in growth to increase the opportunities for identifying the mechanisms involved. The application of results from such research to many forestry situations, however, is harder than from research in which there is a closer match between treatments and management practices. The expectations of process-based models as management tools for economic decision-making is yet to be fulfilled. More progress is required in our ability to predict accurately the effects of soil and stand management practices on the production of marketable wood.The extent to which results of research on silvicultural practices are applied in practice is ultimately dependent upon economic return from investment. Water and nutrient relations have a significant influence on production, harvest index and log and wood quality. Recognition and understanding of this influence and the availability of management-oriented growth models incorporating process-based information, will permit better assessment of potential returns from management options.     

Small Molecules Showing Significant Protection of Mice against Botulinum Neurotoxin Serotype A

Botulinum neurotoxin serotype A (BoNTA) causes a life-threatening neuroparalytic disease known as botulism that could afflict large, unprotected populations if the toxin were employed in an act of bioterrorism. Current post-exposure therapy is limited to symptomatic treatment or passive immunization that is effective for treating infant botulism at a cost of US $45,300 per treatment regimen. Antibodies can neutralize the extracellular but not the intracellular BoNTA. Moreover, antibody production, storage, and administration in a mass casualty scenario pose logistical challenges. Alternatively, small-molecule inhibitors of BoNTA endopeptidase (BoNTAe) are sought to antagonize the extracellular or intracellular toxin. While several such molecules reportedly demonstrated efficacy in protecting cells against BoNTA, there is scant information to show that small molecules can significantly protect mammals against BoNTA. Herein we report the development of effective small-molecules BoNTAe inhibitors with promising in vivo pharmacokinetics. One such molecule has an in vivo half-life of 6.5 hours and is devoid of obvious sign of toxicity. Pre-treatment with this molecule at 2 mg/kg protected 100% and 70% of treated mice against BoNTA at 5 times of its median-lethal dose during the periods of 2 and 4 half-lives of the inhibitor, respectively. In contrast, 40% and 0% of untreated mice survived during the respective periods. Similar levels of protection were also observed with two other small molecules. These results demonstrate that small molecules can significantly protect mice against BoNTA and support the pursuit of small-molecule antagonists as a cost-effective alternative or as an adjunct to passive immunity for treating botulism.     

Correlates of Research Effort in Carnivores: Body Size,Range Size and Diet Matter

Given the budgetary restrictions on scientific research and the increasing need to better inform conservation actions, it is important to identify the patterns and causes of biases in research effort. We combine bibliometric information from a literature review of almost 16,500 peer-reviewed publications on a well-known group of 286 species, the Order Carnivora, with global datasets on species'' life history and ecological traits to explore patterns in research effort. Our study explores how species'' characteristics influenced the degree to which they were studied (measured as the number of publications). We identified a wide variation in intensity of research effort at both Family and Species levels, with some of the least studied being those which may need protection in future. Our findings hint at the complex role of human perspectives in setting research agendas. We found that better-studied species tended to be large-bodied and have a large geographic range whilst omnivory had a negative relationship with research effort. IUCN threat status did not exhibit a strong relationship with research effort which suggests that the conservation needs of individual species are not major drivers of research interest. This work is the first to use a combination of bibliometric analysis and biological data to quantify and interpret gaps in research knowledge across an entire Order. Our results could be combined with other resources, such as Biodiversity Action Plans, to prioritise and co-ordinate future research effort, whilst our methods can be applied across many scientific disciplines to describe knowledge gaps.     

A Stereoselective Synthesis of α - and β-2′-Deoxy-2-thiouridine

Abstract

A stereoselective glycosylation procedure is described for the synthesis of protected α- and β-2′-deoxy-2-thiouridine (dS²U) in 68% and 94% yield, respectively. Evidence is presented that suggests the reaction proceeds through a silylated thio-glycoside intermediate. This intermediate undergoes an efficient S² → N¹ rearrangement mediated by SnCl₄. The phosphoramidite and phosphodiester synthons and a dS²U dinucleotide are also synthesized and the X-ray structure of β-dS²U is presented.     

Chromosomal translocations in cancer

Genetic alterations in DNA can lead to cancer when it is present in proto-oncogenes, tumor suppressor genes, DNA repair genes etc. Examples of such alterations include deletions, inversions and chromosomal translocations. Among these rearrangements chromosomal translocations are considered as the primary cause for many cancers including lymphoma, leukemia and some solid tumors. Chromosomal translocations in certain cases can result either in the fusion of genes or in bringing genes close to enhancer or promoter elements, hence leading to their altered expression. Moreover, chromosomal translocations are used as diagnostic markers for cancer and its therapeutics. In the first part of this review, we summarize the well-studied chromosomal translocations in cancer. Although the mechanism of formation of most of these translocations is still unclear, in the second part we discuss the recent advances in this area of research.     

+]-Huperzine A treatment protects against N-methyl-D-aspartate-induced seizure/status epilepticus in rats

The toxicity of organophosphorous (OP) nerve agents is attributed to their irreversible inhibition of acetylcholinesterase (AChE), which leads to excessive accumulation of acetylcholine (ACh) and is followed by the release of excitatory amino acids (EAA). EAAs sustain seizure activity and induce neuropathology due to over-stimulation of N-methyl-d-aspartate (NMDA) receptors. Huperzine A (Hup A), a blood-brain barrier permeable selective reversible inhibitor of AChE, has been shown to reduce EAA-induced cell death by interfering with glutamate receptor-gated ion channels in primary neuronal cultures. Although [-]-Hup A, the natural isomer, inhibits AChE approximately 38-fold more potently than [+]-Hup A, both [-]- and [+]-Hup A block the NMDA channel similarly. Here, we evaluated the protective efficacy of [+]-Hup A for NMDA-induced seizure in a rat model. Rats implanted with radiotelemetry probes to record electroencephalography (EEG), electrocardiography (ECG), body temperature, and physical activity were administered various doses of [+]-Hup A (intramuscularly) and treated with 20mug/kg NMDA (intracerebroventricular) 20-30min later. For post-exposure, rats were treated with [+]-Hup A (3mg/kg, intramuscularly) 1min after NMDA (20mug/kg). Our data showed that pre- and post-exposure, [+]-Hup A (3mg/kg) protects animals against NMDA-induced seizures. Also, NMDA-administered animals showed increased survival following [+]-Hup A treatment. [+]-Hup A has no visible effect on EEG, heart-rate, body temperature, or physical activity, indicating a reduced risk of side effects, toxicity, or associated pathology. Our results suggest that [+]-Hup A protects against seizure and status epilepticus (SE) by blocking NMDA-induced excitotoxicity in vivo. We propose that [+]-Hup A, or a unique combination of [+]- and [-]-Hup A, may prove to be effective for pre- and post-exposure treatment of lethal doses of OP-induced neurotoxicity.     

The usage of marker traits in plants for evaluation of resistance of the winter wheat to pest insects

A new method of selection of the winter wheat varieties has been tested for resistance to the pest insects' complex by the traits of plants that are the markers of plant resistance. It makes it possible to use this method from year to year independently of the pests' density.     

The ribonuclease from an extinct bovid ruminant

The sequence of the ribonuclease from the ancestor of swamp buffalo, river buffalo, and ox, corresponding approximately to Pachyportax latidens, an extinct ruminant known from the fossil record, has been reconstructed using the rule of 'maximum parsimony'. This protein and two sequences that may have been intermediates in the evolution of modern ribonuclease have been constructed in the laboratory by site-directed mutagenesis, and their properties examined.