Small Molecules Present in the Cerebrospinal Fluid Metabolome Influence Superoxide Dismutase 1 Aggregation

Superoxide dismutase 1 (SOD1) aggregation is one of the pathological markers of amyotrophic lateral sclerosis (ALS), a fatal neurodegenerative disorder. The underlying molecular grounds of SOD1 pathologic aggregation remains obscure as mutations alone are not exclusively the cause for the formation of protein inclusions. Thus, other components in the cell environment likely play a key role in triggering SOD1 toxic aggregation in ALS. Recently, it was found that ALS patients present a specific altered metabolomic profile in the cerebrospinal fluid (CSF) where SOD1 is also present and potentially interacts with metabolites. Here we have investigated how some of these small molecules affect apoSOD1 structure and aggregation propensity. Our results show that as co-solvents, the tested small molecules do not affect apoSOD1 thermal stability but do influence its tertiary interactions and dynamics, as evidenced by combined biophysical analysis and proteolytic susceptibility. Moreover, these compounds influence apoSOD1 aggregation, decreasing nucleation time and promoting the formation of larger and less soluble aggregates, and in some cases polymeric assemblies apparently composed by spherical species resembling the soluble native protein. We conclude that some components of the ALS metabolome that shape the chemical environment in the CSF may influence apoSOD1 conformers and aggregation.     

Chemical composition and physical properties of black liquors and their effects on liquor recovery operation in Brazilian pulp mills

Black liquor is the major by-product and fuel of pulp mills. In this work, effects of black liquor properties on its recovery unit operation are analyzed. Thus, an experimental methodology for characterizing the principal chemical and physical properties of eucalyptus Kraft and bamboo soda black liquors has been developed, including sample collections from six Brazilian mills. Based on results, eucalyptus and bamboo black liquors present higher contents of non-processing elements (NPEs), higher concentration and different molar mass of lignin than those reported by the pine Kraft black liquor. This leads to distinct rheological properties of these liquors. By comparing results obtained for the both liquors, the bamboo and the eucalyptus, the former has the lowest sulfur level, the highest silicon and lignin concentration and, consequently, the highest apparent viscosity.     

Use of Booster Sheds to Improve Performance of 800 kV Multicone Type Insulators Under Heavy Rain

Studies based on AC high voltage tests have been done at Cepel to investigate the performance of 800 kV bushar insulators under heavy wetting conditions. Insulators were tested which are now used on si...     

Intraoperative arthrography and the Ilizarov technique. Role in the correction of paediatric deformity and leg lengthening

We performed intraoperative arthrography of the knee in 12 children with congenital short femur, Blount's disease or Ollier's disease in whom the Ilizarov technique was used for correction of deformity, leg lengthening or both. In each case, arthrography revealed a joint surface considerably different from that assumed from plain radiographs, and resulted in a change in the placement of our reference wires before application of the frame. This gave significant improvement in the mechanical axis obtained at the time of removal of the frame. The technique is safe, cheap and easy to perform. It is a useful adjunct to the application of the Ilizarov frame when used for complex lengthening and correction of deformity in the leg.     

Efficient autoproteolytic processing of the MHV-A59 3C-like proteinase from the flanking hydrophobic domains requires membranes

The replicase gene of the coronavirus MHV-A59 encodes a serine-like proteinase similar to the 3C proteinases of picornaviruses. This proteinase domain is flanked on both sides by hydrophobic, potentially membrane-spanning, regions. Cell-free expression of a plasmid encoding only the 3C-like proteinase (3CLpro) resulted in the synthesis of a 29-kDa protein that was specifically recognized by an antibody directed against the carboxy-terminal region of the proteinase. A protein of identical mobility was detected in MHV-A59-infected cell lysates. In vitro expression of a plasmid encoding the 3CLpro and portions of the two flanking hydrophobic regions resulted in inefficient processing of the 29-kDa protein. However, the efficiency of this processing event was enhanced by the addition of canine pancreatic microsomes to the translation reaction, or removal of one of the flanking hydrophobic domains. Proteolysis was inhibited in the presence of N-ethylmaleimide (NEM) or by mutagenesis of the catalytic cysteine residue of the proteinase, indicating that the 3CLpro is responsible for its autoproteolytic cleavage from the flanking domains. Microsomal membranes were unable to enhance the trans processing of a precursor containing the inactive proteinase domain and both hydrophobic regions by a recombinant 3CLpro expressed from Escherichia coli. Membrane association assays demonstrated that the 29-kDa 3CLpro was present in the soluble fraction of the reticulocyte lysates, while polypeptides containing the hydrophobic domains associated with the membrane pelletes. With the help of a viral epitope tag, we identified a 22-kDa membrane-associated polypeptide as the proteolytic product containing the amino-terminal hydrophobic domain.     

Towards good ecological status of surface waters in Europe--interpretation and harmonisation of the concept.

The Water Framework Directive (WFD) is a new legislative framework to manage, use, protect, and restore surface water and groundwater resources and coastal waters in the European Union (EU). The aim is to ensure sustainable water management and to reach good water quality by 2015. The assessment of the ecological status and setting of the practical management goals require several steps. The process has started with the characterisation of the river basins including identification of surface water bodies and types, and identification of significant anthropogenic pressures and impacts. The water bodies will be classified in five quality classes (high, good, moderate, poor, bad) based on the Ecological Quality Ratio, which is a ratio between reference conditions and measured status of the biological quality elements. The normative criteria for high, good and moderate ecological status described in the WFD need to be made operational because those will be used to set the practical quality targets for surface water management. National ecological assessment systems and classifications will be harmonised through the WFD intercalibration exercise in order to ensure an equal level of ambition in achieving good surface waters status all over Europe.     

Hepatic hemangioma. Analysis of 103 cases. Clinical considerations and imaging methods

Hemangiomas are the most common benign vascular tumor found in the liver. In this study, 103 cases of hepatic hemangiomas were analysed in a retrospective manner. Image aspects such as those seen in ultrassonography, computed tomography, nuclear magnetic resonance and arteriography are discussed. The incidence was higher amongst the female sex, between individuals from 40 to 60 years old, which presented predominantly without symptoms (66%) and localized mainly in the right hepatic lobe (74%). The meaning of those aspects, when adopted, permits the clinicians to differentiate benign from malignant nodular lesions in the liver.     

The role of lymphocyte subsets in accelerated diabetes in nonobese diabetic-rat insulin promoter-B7-1 (NOD-RIP-B7-1) mice

B7-1 transgene expression on the pancreatic islets in nonobese diabetic (NOD) mice leads to accelerated diabetes, with >50% of animals developing diabetes before 12 wk of age. The expression of B7-1 directly on the pancreatic beta cells, which do not normally express costimulator molecules, converts the cells into effective antigen-presenting cells leading to an intensified autoimmune attack. The pancreatic islet infiltrate in diabetic mice consists of CD8 T cells, CD4 T cells, and B cells, similar to diabetic nontransgenic NOD mice. To elucidate the relative importance of each of the subsets of cells, the NOD-rat insulin promoter (RIP)-B7-1 animals were crossed with NOD.beta2microglobulin -/- mice which lack major histocompatibility complex class I molecules and are deficient in peripheral CD8 T cells, NOD.CD4 -/- mice which lack T cells expressing CD4, and NOD.muMT -/- mice which lack B220-positive B cells. These experiments showed that both CD4 and CD8 T cells were necessary for the accelerated onset of diabetes, but that B cells, which are needed for diabetes to occur in normal NOD mice, are not required. It is possible that B lymphocytes play an important role in the provision of costimulation in NOD mice which is unnecessary in the NOD-RIP-B7-1 transgenic mice.     

Photoinduced birefringence in blends of a polyurethane bearing azobenzene moieties and a poly(amide–imide)

A polyurethane (MDI‐DR19Cl) bearing azobenzene moieties was prepared by condensation of 4,4′‐diphenylmethylenediisocyanate and an azobenzene compound, 2‐chloro‐4‐nitro‐4′‐[bis‐(2‐hydroxyethyl)]amine‐azobenzene (DR19Cl). Blends of MDI‐DR19Cl and a poly(amide‐imide) were prepared and characterized by UV‐visible and Fourier transform infrared spectroscopy and by DSC. The purpose of using the blends was to overcome the lack of stability of cast films of pure MDI‐DR19Cl, which tend to crack on storage under ambient conditions. This was successfully achieved and, depending on blend proportions, flexible self‐standing films could be prepared after thermal treatment. Optical storage experiments performed with the blends and pure MDI‐DR19Cl cast films showed a decrease in the remnant values of photoinduced birefringence in the blends (60 % for the blend with 5 wt% MDI‐DR19Cl) compared to pure MDI‐DR19Cl (75%), but, taking into account the low content of MDI‐DR19Cl used, the results obtained are probably sufficient to show the viability of these blends in optical storage applications. Copyright © 2006 Society of Chemical Industry     

Synthesis and flocculation properties of N‐oxide polymers

N‐oxide polymers possess strong zwitterionic character, high solubility in water, and high chelating properties with various cations. In this work, N‐oxide polymers were synthesized following various routes and their solution properties were determined. Molecular properties of the polymers (molecular weight, square root of the mean‐squared radius, and virial coefficients) were related to their chain expansion in solution by determining the intrinsic viscosity as a function of pH. Viscosity results were correlated with the flocculation ability of the polymers for suspending solids removal. These polymers exhibit dramatic conformation changes as the solution pH is varied, especially at low pH values. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 2693–2700, 2002