Trinucleotide (CAG) repeat expansion in chromosomes of Spanish patients with Huntington's disease

Huntington's disease (HD) is a neurodegenerative and hereditary disease characterized by progressive movement disorders and mental and behavioral abnormalities. The HD gene is an expanding and unstable trinucleotide repeat (CAG repeat sequences). We studied 77 individuals from 38 families with HD in an attempt to obtain information for genetic counselling and differential diagnosis. Our results indicate that individuals with more than 40 repeats will be affected by the disease, whereas those with fewer than 30 will be healthy. There can be some overlap between 30 and 40 repeats, and one should be careful when interpreting these results.     

Meta-performance evaluation of sustainability indicators

There are many different kinds of frameworks for evaluating environmental and sustainability performance at the organizational level (profit or not-for-profit, private or public), sectoral level (e.g. industry, transport, agriculture and tourism), and local, regional or country levels. Despite the diversity of methods and tools to measure sustainable development, indicators are one of the approaches most used. However, these tools do not usually include evaluation of the performance measurement instrument itself. The main objective of this research is to develop a conceptual framework to design and assess the effectiveness of the sustainability indicators themselves. To put the proposed tool into practice, a set of key good-practice factors and meta-performance evaluation indicators is proposed for adoption in a national case study—the national sustainable development indicators system, SIDS Portugal, and the usefulness of this methodology is demonstrated. This approach aims to evaluate how appropriate a set of sustainability indicators is and allow an evaluation of overall performance-monitoring activities and results. Stakeholder involvement is an essential component of the proposed framework. The tool developed could support continuous improvement in the performance of ongoing sustainability indicator initiatives, allowing greater guidance, objectivity and transparency in sustainability assessment processes.     

New Insights into the in situ Microscopic Visualization and Quantification of Inorganic Polyphosphate Stores by 4’,6-Diamidino-2-Phenylindole (DAPI)-Staining

Inorganic polyphosphate (PolyP) is a biological polymer that plays important roles in the cell physiology of both prokaryotic and eukaryotic organisms. Among the available methods for PolyP localization and quantification, a 4’,6-diamidino-2-phenylindole(DAPI)-based assay has been used for visualization of PolyP-rich organelles. Due to differences in DAPI permeability to different compartments and/or PolyP retention after fixation, a general protocol for DAPI-PolyP staining has not yet been established. Here, we tested different protocols for DAPI-PolyP detection in a range of samples with different levels of DAPI permeability, including subcellular fractions, free-living cells and cryosections of fixed tissues. Subcellular fractions of PolyP-rich organelles yielded DAPI-PolyP fluorescence, although those with a complex external layer usually required longer incubation times, previous aldehyde fixation and/or detergent permeabilization. DAPI-PolyP was also detected in cryosections of OCT-embedded tissues analyzed by multiphoton microscopy. In addition, a semi-quantitative fluorimetric analysis of DAPI-stained fractions showed PolyP mobilization in a similar fashion to what has been demonstrated with the use of enzyme-based quantitative protocols. Taken together, our results support the use of DAPI for both PolyP visualization and quantification, although specific steps are suggested as a general guideline for DAPI-PolyP staining in biological samples with different degrees of DAPI and PolyP permeability.Key words: DAPI, polyphosphate, fluorescence, fluorimetry     

Characterization of the sugar-binding specificity of the toxic lectins isolated from Abrus pulchellus seeds

The sugar-binding specificity of the toxic lectins from Abrus pulchellus seeds was investigated by combination of affinity chromatography of glycopeptides and oligosaccharides of well-defined structures on a lectin-Sepharose column and measurement of the kinetic interactions in real time towards immobilized glycoproteins. The lectins showed strong affinity for a series of bi- and triantennary N-acetyllactosamine type glycans. The related asialo-oligosaccharides interact more strongly with the lectins. The best recognized structures were asialo-glycopeptides from fetuin. Accordingly, the kinetic interaction with immobilized asialofetuin was by far the most pronounced. Human and bovine lactotransferrins and human serotransferrin interacted to a lesser extent. The interaction with asialofetuin was inhibited by galactose in a dose dependent manner. Lactose, N-acetyllactosamine and lacto-N-biose exhibited similar degree of inhibition while N-acetylgalactosamine was a poor inhibitor. These results suggested that the carbohydrate-binding site of the Abrus pulchellus lectins was specific for galactose and possess a remarkable affinity for the sequences lactose [-D-Gal-(14)-D-Glc], N-acetyllactosamine [-D-Gal-(14)-D-GlcNAc] and lacto-N-biose [-D-Gal-(13)-D-GlcNAc].     

Anti-Sporothrix Antibody Detection in Domestic Cats as an Indicator of a Possible New Occurrence Area for Sporotrichosis in North Brazil

Mycopathologia - Feline sporotrichosis has emerged as an important public health issue in some countries, especially Brazil. Currently, zoonotic transmission of Sporothrix brasiliensis by domestic...     

ChemMatrix® for complex peptides and combinatorial chemistry

CM resin is a totally PEG‐based resin, made exclusively from primary ether bonds and therefore highly chemically stable. Compared to other PEG resins, it exhibits good loading and is user friendly because of its free‐flowing form upon drying. It shows improved performance over PS resins for the preparation of hydrophobic, highly structured poly‐Arg peptides. In combination with ψPros, it allows the synthesis of small proteins such as the chemokine RANTES. Like other PEG‐based resins, CM resin swells well in biocompatible solvents such as water, thereby allowing on‐bead screening. Furthermore, the high loading of this resin permits the use of a tiny quarter of a bead as a microreactor for HPLC and MALDI‐TOF analysis, thus further extending its applications in the field of combinatorial chemistry. Copyright © 2010 European Peptide Society and John Wiley & Sons, Ltd.