Can the biology of VEGF and haem oxygenases help solve pre-eclampsia?

Pre-eclampsia, a pregnancy-specific multi-organ syndrome characterized by widespread endothelial damage, is a new risk factor for cardiovascular disease. No therapies exist to prevent or treat this condition, even to achieve a modest improvement in pregnancy length or birth weight. Co-administration of soluble VEGFR-1 [VEGF (vascular endothelial growth factor) receptor-1; more commonly known as sFlt-1 (soluble Fms-like tyrosine kinase-1)] and sEng (soluble endoglin) to pregnant rats elicits severe pre-eclampsia-like symptoms. These two anti-angiogenic factors are increased dramatically prior to the clinical onset of pre-eclampsia and are quite possibly the 'final common pathway' responsible for the accompanying signs of hypertension and proteinuria as they can be reversed by VEGF administration in animal models. HO-1 (haem oxygenase-1), an anti-inflammatory enzyme, and its metabolite, CO (carbon monoxide), exert protective effects in several organs against oxidative stimuli. In a landmark publication, we showed that the HO-1 pathway inhibits sFlt-1 and sEng in cultured cells and human placental tissue explants. Both CO and NO (nitric oxide) promote vascular homoeostasis and vasodilatation, and activation of VEGFR-1 or VEGFR-2 induced eNOS (endothelial nitric oxide synthase) phosphorylation, NO release and HO-1 expression. Our studies established the HO-1/CO pathway as a negative regulator of cytokine-induced sFlt-1 and sEng release and eNOS as a positive regulator of VEGF-mediated vascular morphogenesis. These findings provide compelling evidence for a protective role of HO-1 in pregnancy and identify it as a target for the treatment of pre-eclampsia. Any agent that is known to up-regulate HO-1, such as statins, may have potential as a therapy. Any intervention achieving even a modest prolongation of pregnancy or amelioration of the condition could have a significant beneficial health impact worldwide.

A simple and efficient procedure for Knoevenagel reaction promoted by imidazolium-based ionic liquids

Various room temperature ionic liquids (RTILs), notably, 1-methoxyethyl-3-methylimidazolium trifluoroacetate [MeOEtMIM]+[CF3COO]ˉ , have been used to promote the Knoevenagel condensation to afford substituted olefins. All reactions proceeded effectively in the absence of any other catalysts or co-solvents with good to excellent yields. This method is simple and applicable to reactions involving a wide range of aldehydes and ketones with methylene compounds. The ionic liquid can be recycled without noticeable reduction of its catalytic activity. A plausible reaction mechanism is proposed.

Linear Fresnel mirror solar concentrator with tracking

Solar energy is the most abundant, widely distributed and clean renewable energy resource. Since the insolation intensity is only in the range of 0.5 - 1.0 kW/m2, solar concentrators are required for attaining temperatures appropriate for medium and high temperature applications. The concentrated energy is transferred through an absorber to a thermal fluid such as air, water or other fluids for various uses. This paper describes design and development of a 'Linear Fresnel Mirror Solar Concentrator' (LFMSC) using long thin strips of mirrors to focus sunlight on to a fixed receiver located at a common focal line. Our LFMSC system comprises a reflector (concentrator), receiver (target) and an innovative solar tracking mechanism. Reflectors are mirror strips, mounted on tubes which are fixed to a base frame. The tubes can be rotated to align the strips to focus solar radiation on the receiver (target). The latter comprises a coated tube carrying water and covered by a glass plate. This is mounted at an elevation of few meters above the horizontal, parallel to the plane of the mirrors. The reflector is oriented along north-south axis. The most difficult task is tracking. This is achieved by single axis tracking using a four bar link mechanism. Thus tracking has been made simple and easy to operate. The LFMSC setup is used for generating steam for a variety of applications. © 2013 The Authors. Published by Elsevier Ltd.

Isolation and characterization of the U1 and U2 snRNAs in the silk gland of the 5th instar larval stage silk moth Bombyx mori

In isolation and characterization studies, expression level U1 and U2 snRNA isoforms were obtained from the 5th instar larval stage silk gland (SG). The DNA content of the SG cells is approximately 200,000-fold higher compared to the usual (2N) somatic cells of B. mori due to endoreduplication. In this study, the existence of U1 and U2 snRNA isoforms in the SG of the organism is investigated. Bombyx mori U1 and U2-specific RT-PCR libraries from the silk gland were generated. Five U1 and eight U2 isoforms were isolated and characterized. Nucleotide differences, structural alterations, as well as protein and RNA interaction sites were analyzed in these variants. For the U1 snRNA variants, they were compared to the previously reported BmN isoforms. In all these U-snRNA variants, polymorphic sites do not predominate at the core of known functional sequences, which were interspecifically conserved. Variant sites and inter-species differences are located in moderately conserved regions. Free energy (ΔG) values for the entire U1 and U2 snRNA secondary structures and for the individual stem/loops domains of the isoforms were generated and compared to determine their structural stability. This will be the first time that U1 and U2 variants are shown specific for a development stage (larval) other than embryonic or adult. ^ Using phylogenetic analysis, evolutionary trees were generated for the U1 and U2 snRNAs using animal, plant, protista and fungal species. The resulting trees were boostrapped for robustness and rooted with the self-splicing RNA group II intron sequence from the cyanobacterium Calothrix. Using phylogenetic analyses, possible structural and functional evolutionary interdependence between the U1 and U2 snRNAs was investigated. ^

Kinetic modeling of molecular motors: pause model and parameter determination from single-molecule experiments

Single-molecule manipulation experiments of molecular motors provide essential information about the rate and conformational changes of the steps of the reaction located along the manipulation coordinate. This information is not always sufficient to define a particular kinetic cycle. Recent single-molecule experiments with optical tweezers showed that the DNA unwinding activity of a Phi29 DNA polymerase mutant presents a complex pause behavior, which includes short and long pauses. Here we show that different kinetic models, considering different connections between the active and the pause states, can explain the experimental pause behavior. Both the two independent pause model and the two connected pause model are able to describe the pause behavior of a mutated Phi29 DNA polymerase observed in an optical tweezers single-molecule experiment. For the two independent pause model all parameters are fixed by the observed data, while for the more general two connected pause model there is a range of values of the parameters compatible with the observed data (which can be expressed in terms of two of the rates and their force dependencies). This general model includes models with indirect entry and exit to the long-pause state, and also models with cycling in both directions. Additionally, assuming that detailed balance is verified, which forbids cycling, this reduces the ranges of the values of the parameters (which can then be expressed in terms of one rate and its force dependency). The resulting model interpolates between the independent pause model and the indirect entry and exit to the long-pause state model

G protein-coupled receptors:essential methods

G-Protein Coupled Receptors (GPCRs) are not only the largest protein family in the human genome but are also the single biggest target for therapeutic agents. Research into GPCRs is therefore growing at a fast pace and the range of techniques that can be applied to GPCRs is vast and continues to grow. This book provides an invaluable bench-side guide into the best and most up-to-date techniques for current and future research on GPCRs. With contributions from leading international authorities, this book equips readers with clear and detailed protocols for both well-known and up-and-coming techniques along with hints and tips for success. All the methods have been tried and tested by leading international research labs and are presented in easy-to-follow stages along with a useful overview of each technique. This book is an essential resource for all researchers in molecular biology, biochemistry, pharmacology and for graduate students.© 2010 John Wiley & Sons, Ltd.

(Table 1) Low molecular weight hydrocarbon concentrations and organic carbon contents at DSDP Hole 71-511

C2-C8 hydrocarbons (36 compounds identified) from 56 shipboard sealed, deep-frozen core samples of DSDP Leg 71, Site 511, Falkland Plateau, South Atlantic, were analyzed by a combined hydrogen stripping-thermovaporization method. Concentrations, which represent hydrocarbons dissolved in the pore water and adsorbed to the mineral surfaces of the sediment, vary from 24 ng/g of dry weight sediment in Lithologic Unit 4 to 17,400 ng/g in Lithologic Unit 6 ("black shale" unit). Likewise, the organic carbon normalized C2-C8 hydrocarbon concentrations range from 104 to 3.5 x 105 ng/g Corg. The latter value is more than one order of magnitude lower than expected for petroleum source beds in the main phase of oil generation. The low maturity at 600 meters depth is further supported by light hydrocarbon concentration ratios. The change of the kerogen type from Lithologic Unit 5 (Type III) to 6 (Type II) is evidenced by changes in the C6 and C7 hydrocarbon composition. Redistribution phenomena are observed close to the Tertiary-Cretaceous unconformity and at the contact between the "black shale" unit and the overlying Cretaceous chalks and claystones. Otherwise, the low molecular weight hydrocarbons in Hole 511 are formed in situ and remain at their place of formation. The core samples turned out to be contaminated by large quantities of acetone, which is routinely used as a solvent during sampling procedures onboard Glomar Challenger.

Fishing gear selectivity for Lates niloticus L., Oreochromis niloticus L. and Rastrineobola argentea P. in Lakes Victoria, Kyoga and Nabugabo

Catch effort data on which fisheries management regulations are sometimes based are not available for most lakes in Uganda. However, failure to regulate fishing gears and methods has been a major cause of collapse of fisheries in the country. Fisheries have been damaged by destructive and non-selective fishing gears and methods such as trawling and beach seining, by use of gill nets of mesh size which crop immature fish and by introduction of mechanised fishing. Selectivity of gears used to crop Lates niloticus L.(Nile perch), Oreochromis niloticus L. (Nile tilapia) and Rastrineobola argentea Pellegrin (Mukene) which are currently the most important commercial species in Uganda were examined in order to recommend the most suitable types, sizes and methods that should be used in exploiting these fisheries. Gill nets of less than 127 mm mainly cropped immature Nile tilapia and Nile perch. To protect these fisheries, the minimum mesh size of gill nets should be set at 127 mm. Seine nets of 5 mm caught high proportions in immature Mukene while those of 10 mm caught mainly mature Mukene. When operated inshore, both sizes caught immature Nile perch and Nile tilapia as by-catch. To protect the Mukene fishery and avoid catching immature bye-catch, a minimum mesh size of the Mukene net should be 10 mm operated as Lampara type net offshore, but since most fishermen have been using 5 mm seine nets for over five years the minimum size should not be allowed to drop below 5 mm pending further thorough investigations. Beach seining and trawling are destructive to fisheries and should be prohibited until data that may justify their use is available.

Molecular analysis of RNA1 and RNA2 sequences from a betanodavirus isolated from giant grouper (Epinephelus lanceolatus) in Australia

Betanodavirus infections have a significant impact through direct losses and trade restrictions for aquaculture sectors in Australia. The giant grouper, Epinephelus lanceolatus, is a high-value, fast-growing species with significant aquaculture potential. With subacute to chronic mortalities reported from a commercial aquaculture facility in northern Queensland, the viral nervous necrosis in the affected fish was confirmed using a RT-qPCR followed by virus isolation using the SSN-1 cell line. The RNA1 and RNA2 segments were sequenced and nucleotide sequences were compared with betanodavirus sequences from GenBank. Phylogenetic analysis revealed that both these sequences clustered with sequences representing red spotted grouper nervous necrosis virus genotype and showed high sequence identity to virus sequences affecting other grouper species. This is the first report confirming infection by betanodavirus in E. lanceolatus from Australia with successful isolation of the virus in a cell culture system, and analysis of nearly full length RNA1 and RNA2 sequences.

Soil Health, Soil Biology, Soilborne Diseases and Sustainable Agriculture

Soil Health, Soil Biology, Soilborne Diseases and Sustainable Agriculture provides readily understandable information about the bacteria, fungi, nematodes and other soil organisms that not only harm food crops but also help them take up water and nutrients and protect them from root diseases. Complete with illustrations and practical case studies, it provides growers and their consultants with holistic solutions for building an active and diverse soil biological community capable of improving soil structure, enhancing plant nutrient uptake and suppressing root pests and pathogens.

Large-scale neural dynamics: simple and complex

We review the use of neural field models for modelling the brain at the large scales necessary for interpreting EEG, fMRI, MEG and optical imaging data. Albeit a framework that is limited to coarse-grained or mean-field activity, neural field models provide a framework for unifying data from different imaging modalities. Starting with a description of neural mass models we build to spatially extended cortical models of layered two-dimensional sheets with long range axonal connections mediating synaptic interactions. Reformulations of the fundamental non-local mathematical model in terms of more familiar local differential (brain wave) equations are described. Techniques for the analysis of such models, including how to determine the onset of spatio-temporal pattern forming instabilities, are reviewed. Extensions of the basic formalism to treat refractoriness, adaptive feedback and inhomogeneous connectivity are described along with open challenges for the development of multi-scale models that can integrate macroscopic models at large spatial scales with models at the microscopic scale.

E-cadherin and Choline Kinase: two challenging drug discovery targets

The data presented in this thesis was generated using molecular biology, protein chemistry and X-ray crystallography techniques. However, while the methodologies employed are essentially the same, the research work presented here refers to two different proteins, which are part of different research projects in the laboratory. For this reason, the content of this thesis is divided in two independent parts, each provided with an introduction and a general overview of the research topic and state-ofthe- art, a materials and methods section discussing the techniques used and the protocols followed, and a section where the results are presented and discussed in detail. The first half of the thesis deals with the structural characterization of the complex between human E-cadherin and three different small molecule potential inhibitors identified via a fragment-based drug discovery (FBDD) screening campaign that was conducted using a library of commercially available small fluorinated chemical fragments. For this screening phase, we used 19F-NMR as readout. The NMR experiments were done by our collaborator Dr. Marina Veronesi at the D3 PharmaChemistry division of the Italian Institute of Technology (IIT) in Genova (Italy). Functional cell adhesion assays to validate the inhibitory effects of the fragments thus identified were carried out in collaboration with Prof. Frédéric André at the University of Marseille (France). The second half of the thesis describes the structural characterization of Plasmodium falciparum Choline Kinase (PfChoK), an important pharmaceutical target in the fight against malaria, as well as the biochemical characterization of a library of potential inhibitors of PfChoK. These inhibitors were synthetized in the group of Prof. Luisa Carlota López-Cara at the Department of Pharmaceutical and Organic Chemistry of the University of Granada (Spain) in the framework of an ongoing collaboration between the two groups.