Absent pulmonary valve with intact ventricular septum and patent ductus arteriosus: a specific cardiac phenotype associated with deletion 18q syndrome.
Explore the source record for details and available documents.
Abnormalities, Multiple↗
Biomedical subjects
Ursula Sauer
Publications and source records attributed to Ursula Sauer.
Quick and simple: quality control of microarray data.
MOTIVATION: Microarrays are high-throughput tools for parallel miniaturized detection of biomolecules. In contrast to experiments using ratios of signals in two channels, experiments with only one fluorescent dye cause special problems for data analysis. The present work compares algorithms for quality filtering on spot level as well as array/slide level. RESULTS: Methods for quantitative spot filtering are discussed and new sets of quality scores for data preprocessing are designed. As measures of spot quality also reflect the quality of protocols, they were employed to find the optimal print buffer in an optimization experiment. In order to determine problematic arrays within a set of replicates we tested methods of outlier detection which can suitably replace the visual inspection of slides. CONTACT: Ursula.Sauer@arcs.ac.at.
Algorithms↗
Photoactivatable copolymers of vinylbenzyl thiocyanate as immobilization matrix for biochips.
Biochip surfaces for immobilization of DNA and proteins require reactive polymers with high immobilization capacity and low nonspecific binding. Most reactive surfaces consist of matrixes that provide epoxy, aldehyde, or amino functions for biomolecule binding. The most widely used oligonucleotide modification is a C6-amino link. The high reactivity of isothiocyanate groups (NCS) toward amines was therefore the motivation to employ photogenerated NCS groups as binding sites for NH(2)-terminated oligonucleotides. Photosensitive poly(styrene-co-4-vinylbenzyl thiocyanate) (PST-co-VBT) was synthesized and applied as novel material for DNA and protein immobilization. The immobilization capacity of PST-co-VBT was a function of UV energy density used for photoactivation and was approximately 80% at 450 mJ cm(-)(2) (lambda(ex) = 254 nm). This surface was superior to tested commercial chip surfaces in signal-to-noise-ratio and reproducibility. Print buffer and spacer length were optimized for maximum fluorescence signal with DNA and proteins. UV exposure conditions and oligonucleotide modification were correlated, showing that this photochemical approach can be successfully applied for surface patterning of biochips.
Base Sequence↗
ARChip epoxy and ARChip UV for covalent on-chip immobilization of pmoA gene-specific oligonucleotides.
ARChip Epoxy and ARChip UV are presented as novel chip platforms for oligonucleotide immobilization. ARChip Epoxy is made of reactive epoxy resin available commercially. ARChip UV consists of photoactivatable poly(styrene-co-4-vinylbenzylthiocyanate). Both ARChip surfaces are tested in a model assay based on oligonucleotide probes from a real-life genotyping project and are evaluated in comparison with five commercial chip surfaces based on nitrocellulose, epoxy, and aldehyde polymer, and two different aminosilanes. Optimum print buffer, spotter compatibility, and data normalization are discussed.
Bacteria↗
Genetics of congenital heart defects.
Explore the source record for details and available documents.
Heart Defects, Congenital↗
Protein-losing enteropathy in patients with Fontan circulation: is it triggered by infection?
INTRODUCTION: Protein-losing enteropathy (PLE) is a recognised complication of the Fontan circulation. Its pathogenesis is not fully understood, however, and it is unclear why its onset occurs months or even years after Fontan surgery. PATIENTS: We report a 4.5-year-old girl with Fontan circulation who developed PLE almost 1 year after surgery. At the time of onset the patient had rotavirus enteritis and streptococcal tonsillitis. We have reviewed the records of seven other patients with longstanding PLE. In six of these patients we identified infections at the onset of symptoms. None of our patients had evidence of opportunistic infection. DISCUSSION AND CONCLUSION: The immune system of patients with PLE is compromised, but reports on recurrent opportunistic infections are rare. The present observations suggest that infection and inflammation may be associated with the onset of PLE. The mechanism of how infection may trigger PLE warrants further investigation.
Child↗
Impact of simian immunodeficiency virus (SIV) infection on lymphocyte numbers and T-cell turnover in different organs of rhesus monkeys.
HIV infection leads to reduced numbers and increased turnover of CD4(+) T cells in blood. However, blood represents only 2% of the total lymphocyte pool, and information about other organs is lacking, leading to controversy about the effects of HIV infection on T-cell homeostasis. Therefore, we have determined phenotype and turnover of lymphocyte subsets in various tissues of macaques. Infection with simian immunodeficiency virus (SIV) resulted in increased proliferation rates of T cells in all organs. Despite reduced CD4 counts in blood, absolute numbers of CD4(+) T cells were increased in spleen and lymph nodes and remained stable in nonlymphoid organs such as liver, lung, bone marrow, and brain during the asymptomatic phase, indicative for an altered tissue distribution. In animals killed with first signs of AIDS, total body CD4 counts and proliferation rates had returned to control levels, whereas thymocytes were almost completely absent. Our data show that a drastically increased turnover in the early stages of HIV infection, driven by a generalized immune activation rather than a homeostatic response to CD4(+) T-cell destruction, is followed by exhaustion of the regenerative capacity of the immune system.
Animals↗
The new EU chemicals policy--Discussions on details relevant for animal welfare.
The European Commission is planning to put forward drafts for a new chemicals legislation by June 2002. In fulfillment of an Environmental Council Conclusion, Working Groups have been set up for consultation during the ongoing preparatory stage. There, members of the General Directorates Environment and Enterprise discuss relevant topics with representatives from authorities, industry, environmental and animal protection organisations. There is agreement that animal tests shall be reduced to a minimum. However it is still unclear how this goal can best be achieved. In this context, the designing of testing strategies will play a major role. It is explained, why fixed test catalogues should be replaced by flexible tiered testing strategies and how concrete waiving strategies can contribute to avoiding animal tests. Another important aspect is the EU-wide implementation of a clause on the avoidance of duplicate testing, which is already enforced in Germany and Austria. In these Member States, first parties have to provide data from previously performed animal tests to second parties. Finally, it is discussed that the application of new non-animal tests can be promoted, if the revised EU chemicals policy once again contains the legal framework for an EU-specific acceptance of new test methods.
Animal Testing Alternatives↗
[Comment on the combined position of the state government, the union of the chemical industry and the industrial mining association, chemistry, energy for the White Paper of the European Commission "Strategy for future Chemical Policy"].
Explore the source record for details and available documents.
Chemistry↗