Browsing by Author "Beck, M."

A novel loss-of-function mutation in the GNS gene causes Sanfilippo syndrome type D: Mucopolysaccharidosis type IIID (MIM 252940) is the least common form of the four subtypes of Sanfilippo syndrome. It is an autosomal recessive lysosomal disorder caused by a deficiency of the N-acetylglucosamine-6-sulphatase (GlcNAc-6S sulphatase, GNS), a hydrolase, which is one of the enzymes involved in heparan sulfate catabolism leading to lysosomal storage. The clinical features of this disorder are progressive neurodegeneration with relatively mild somatic symptoms. Twenty patients have been described in the literature and only seven causative mutations in the GNS gene encoding GlcNAc-6S sulphatase have been reported to date. We present the clinical and molecular results of a newly diagnosed Turkish patient with MPS IIID. We identified the novel homozygous single base pair insertion, c. 1226GinsG, which leads to a frame-shift and a premature truncation of the GNS protein (p.R409Rfs21X). Conclusion: This novel mutation provides further evidence that loss-of-function is the underlying pathophysiological mechanism of this rare phenotype.

We investigated the effect of light availability and soil moisture on growth and biomass partitioning of Norway spruce and European beech seedlings in a three (light availability levels) × two (soil moisture levels) factorial greenhouse experiment. The effects of factor levels on allocation to biomass compartments were analyzed using ANCOVA. As plant allocation patterns are size-dependent, tree size was used as a covariate. In both tree species, growth and biomass allocation to above and belowground plant components were affected by light availability. European beech showed a distinct increase in allocation to leaves, stem and branch biomass at the expense of fine and coarse roots with decreasing light availability. For Norway spruce, only allocation to stem biomass increased and allocation to fine root biomass decreased under low light. To drought a significant increase of the percentage of belowground compartments was found for European beech but not for Norway spruce. Overall, European beech seedlings were more plastic than Norway spruce seedlings. European beech seedlings appear better able to adjust biomass partitioning to resource availability. In contrast Norway spruce responded languidly. Our results indicate that biomass partitioning is not only driven by ontogeny, and thus tree size, but is environmentally determined to a substantial degree. A possible explanation for this divergence from other results on the role of ontogeny in biomass partitioning may be that seedling plasticity in response to limited resources declines with increasing age and/or time of exposure to the limited resources.

At Bayer CropScience combinatorial chemistry has been used to significantly increase and diversify the compound collection for high throughput in vitro and in vivo screening. Quality aspects were seen critical along this process, from the selection of novel chemotypes with a known biological background to the purity of the test compounds. This will be exemplified by a benzotriazole library obtained by a polymer-bound version of the Sanger reagent attached via a traceless triazene linker (T1). After identification of initial fungicidal activity a thorough analysis in all relevant internal chemical and biological databases revealed the structural requirements for 2(nd) validation libraries, increasing the success likelihood to find potential leads worth further optimization. In a second combinatorial approach peptides with an agro-relevant mode of action will be used to derive new active ingredients. Based on cyclopropylideneacetate chemistry, a structurally extremely flexible peptidomimetic system has been developed for systematic modification of biologically important peptide motifs in potentially optimized conformations. The next step will be the identification of analogues based on this structural informations.

The efficacy and safety of creatine monohydrate (Cr) in patients with myotonic dystrophy type 2/proximal myotonic myopathy were studied in a small placebo-controlled double-blind trial. Twenty patients received either Cr or placebo for 3 months. After 3 months, there were no significant differences of muscle strength as assessed by hand-held dynamometry, testing of maximum grip strength, Medical Research Council scoring, and the Neuromuscular Symptom Score between the two groups. Some measures indicated trends toward mild improvement with Cr. Myalgia improved in two patients.

In this article we describe the test of a zone plate monochromator for a laboratory soft x-ray source which is a laser produced plasma on a liquid jet target. The monochromator consists of a zone plate and a pinhole. Due to the special zone plate used (condensor zone plate KZP7) the monochromator is particularly suitable for laboratory sources since it collects a relatively large solid angle in the present setup. Depending upon the diameter of the pinhole a monochromaticity of up to lambda/Delta lambda =600 can be achieved. The usefulness of the linear monochromator was proven on the basis of a filter transmission measurement. The monochromator can be used for several applications. In particular it is suitable for time-resolved x-ray absorption spectroscopy and pump and probe experiments. The use for such investigations is discussed. (C) 2001 American Institute of Physics.