Biomedical subjects

S Wildt

Publications and source records attributed to S Wildt.

13 recordsLinked to original sources

PubMed2003

Bile acid malabsorption in patients with chronic diarrhoea: clinical value of SeHCAT test.

BACKGROUND: Bile acid malabsorption (BAM), a cause of chronic diarrhoea, can be diagnosed by the SeHCAT test. The purpose of this study was to evaluate the usefulness of SeHCAT testing by assessing the extent of BAM and describing the clinical characteristics in a group of patients with chronic diarrhoea. Clinical outcome after treatment with cholestyramine was also evaluated. METHODS: During a 5-year period (1997-2001) the SeHCAT test was performed in 135 patients in whom a primary programme for diagnostic evaluation of chronic diarrhoea had not revealed a cause. File data from 133 patients could be evaluated. RESULTS: In 44% of patients, bile acid absorption was normal with SeHCAT retention > or = 15%. Impaired SeHCAT retention was found in 56%. All patients with ileocaecal resections had retention values < 10%. Patients with microscopic colitis presented with BAM in 39%. Only one patient with idiopathic BAM presented with steatorrhoea as opposed to 11 patients with type 1 and 3 BAM. Patients with idiopathic BAM and/or SeHCAT retention values < 5% had the best response to treatment with cholestyramine. CONCLUSIONS: The SeHCAT test is of value in evaluation of patients with chronic diarrhoea as a second-line investigation with a high diagnostic yield. The only a priori parameter to predict BAM was the existence of ileocaecal resections. The result of the SeHCAT test seems to predict the benefit of treatment with cholestyramine.

Adult↗

PubMed2002

Genome-wide screening for trait conferring genes using DNA microarrays.

We report a DNA microarray-based method for genome-wide monitoring of competitively grown transformants to identify genes whose overexpression confers a specific cellular phenotype. Whereas transcriptional profiling identifies differentially expressed genes that are correlated with particular aspects of the cellular phenotype, this functional genomics approach determines genes that result in a specific physiology. This parallel gene-trait mapping method consists of transforming a strain with a genomic library, enriching the cell population in transformants containing the trait conferring gene(s), and finally using DNA microarrays to simultaneously isolate and identify the enriched gene inserts. Various methods of enrichment can be used; here, genes conferring low-level antibiotic resistance were identified by growth in selective media. We demonstrated the method by transforming Escherichia coli cells with a genomic E. coli library and selecting for transformants exhibiting a growth advantage in the presence of the anti-microbial agent Pine-Sol. Genes conferring Pine-Sol tolerance (19 genes) or sensitivity (27 genes) were identified by hybridizing, on DNA microarrays containing 1,160 E. coli gene probes, extra-chromosomal DNA isolated from transformed cells grown in the presence of various levels of Pine-Sol. Results were further validated by plating and sequencing of individual colonies, and also by assessing the Pine-Sol resistance of cells transformed with enriched plasmid library or individual resistance genes identified by the microarrays. Applications of this method beyond antibiotic resistance include identification of genes resulting in resistance to chemotherapeutic agents, genes yielding resistance to toxic products (recombinant proteins, chemical feedstocks) in industrial fermentations, genes providing enhanced growth in cell culture or high cell density fermentations, genes facilitating growth on unconventional substrates, and others.

Chromosome Mapping↗

PubMed2001

[Kingella kingae osteomyelitis].

A case of Kingella kingae osteomyelitis in a 1-year-old child is described. Kingella kingae osteoarticular infections in children and the difficulties of isolating this slow growing, fastidious bacterium are discussed.

Diagnosis, Differential↗

PubMed1999

cobA, a red fluorescent transcriptional reporter for Escherichia coli, yeast, and mammalian cells.

We demonstrate the use of Propionibacterium freudenreichii uroporphyrinogen III methyltransferase (cobA) as a reporter of gene expression in Escherichia coli, fission yeast, and mammalian cells. Overexpression of cobA in cells resulted in bright red fluorescence that was visualized with standard fluorescence microscopy and fluorescence-activated cell sorting analysis at the single-cell level. As with green fluorescent protein (GFP), no addition of exogenous substrate was required. When expressed in Chinese hamster ovary cells from a bicistronic transcript, cobA and GFP gave rise to fluorescence signals of similar intensity. The bright red fluorescence generated by the cobA reporter promises a better signal-to-noise ratio than blue and green fluorescent reporter systems, as autofluorescence and light scattering of cells, media, and materials are reduced in the red wavelengths.

Animals↗

PubMed1996

Expression of a novel murine homeobox gene in the developing cerebellar external granular layer during its proliferation.

The TGIF homeobox gene encodes a homeoprotein that represses the 9-cis retinoic acid receptor-dependent transcription activation. To investigate the potential role of this gene in vertebrate development, we have isolated cDNA clones of the murine TGIF (mTGIF) gene and analyzed its expression pattern during mouse embryogenesis and postnatal development by Northern analysis, reverse transcriptase-polymerase chain reaction (RT-PCR), and in situ hybridization histochemistry. mTGIF transcripts were detected at day E16 in the emerging external granular layer (EGL), the cells of which arise from the proliferating cerebellar neuroepithelium. Expression of mTGIF transcripts was also detected at day E16 in the proliferating cells in the neuroepithelium of the hippocampal formation. Following gestation, mTGIF expression increases to a maximum between postnatal days 5 and 10 (PN5 and PN10) in the rapidly expanding cerebellar EGL. mTGIF transcripts are no longer detectable when EGL proliferation ceases on approximately day PN15. Throughout embryo development and in the adult mice, TGIF is detected in a restricted number of tissues, mostly in proliferating and differentiating cell lineages, such as tongue and testis. Our results suggest that the TGIF gene regulates target genes involved in the proliferation, migration, and/or differentiation of particular neuronal cell lineages in the developing brain.

Amino Acid Sequence↗

PubMed1984