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Der aktuelle Entwurf zur Anderung der Futtermittelverordnung sieht vor, dass Hersteller und Uberwachungsbehorden das Dioxin- und PCB-Monitoring ausweiten. Probenaufkommen und die Nachfrage nach kostengunstigen Dioxin-und PCB-Analysen werden daher ansteigen. Erfordern diese Grenzwertprufungen immer den Einsatz der hochauflosenden Massenspektrometrie?

The use of thin silicon wafers is an enabling technology for 3D integration in the semiconductor industry. However, thin silicon wafers are fragile to handle and reliable solutions are required for ...

Background Glycoprotein (GP) IIb/IIIa antagonists are potent inhibitors of thrombocyte aggregation and thrombus formation. Several large-scale randomized studies for prevention of thrombotic complications have shown their potential to reduce these complications in patients undergoing percutaneous transluminal coronary angioplasty (PTCA). It was the purpose of this observational trial to assess the frequency and efficacy of primary GP IIb/IIIa antagonist therapy as a bailout procedure for the prevention of threatened or abrupt vessel closure in patients after conventional balloon angioplasty. Methods And Results From January 1995 to December 1996, PTCA was performed in 1332 consecutive patients with coronary artery disease. Overall, threatened or abrupt vessel closure was observed in 63 (4.7%) patients of the patient population. In these patients, abciximab was administered (0.25 mg/kg body weight intravenous bolus, followed by a 12-hour infusion at 10 μg/min). Repeat PTCA was performed shortly after the administration of the abciximab bolus to achieve an optimal flow at the time of active GP IIb/IIIa therapy. One day after intervention, early follow-up angiography was performed. Follow-up after 1 year included the clinical status of all patients and, if possible, control angiography. Overall, the preintervention minimum lumen diameter (MLD) measured 0.74 ± 0.27 mm and the diameter stenosis was 75% ± 24%. The postintervention MLD increased to 2.60 ± 0.55 mm, and the diameter stenosis decreased to 24% ± 22%. At 24-hour angiographic follow-up, the MLD decreased to 2.47 ± 0.49 mm and the diameter stenosis increased to 28% ± 24%, correspondingly. The thrombus score decreased from 2.8 ± 1.5 before abciximab treatment to 0.88 ± 0.81 after abciximab treatment, and Thrombolysis In Myocardial Infarction flow grade increased from 2.1 ± 1.1 to 2.9 ± 0.3. In-hospital events occurred in 2 patients. Both patients had to undergo emergency coronary artery bypass grafting (1 of these patients died). During long-term follow-up, there were 10 clinical events (1 death, 3 repeat PTCA, and 6 coronary artery bypass graft operations for restenosis at the target lesion site). The cumulative event rate after 1 year (including acute and follow-up events) for both the total group and for the target vessel was 19%. Conclusions The results of this study demonstrate that GP IIb/IIIa antagonists are able to prevent vessel occlusion after PTCA complicated by subsequent threatened or abrupt vessel closure. In these situations, GP IIb/IIIa antagonists provide effective treatment for the reduction of thrombus at the target lesion site, which constitutes a second key element for threatened or abrupt vessel occlusion. (Am Heart J 1999;137:234-40.)

The piezoresistive effect in graphene has been experimentally demonstrated for both uniaxial and biaxial strains. For uniaxial strain, rectangular membranes were measured while circular membranes provided biaxial strain. Gauge factors have also been extracted and compared to previous literature as well as simulations. QC 20160615

Pressure sensors based on suspended graphene membranes have shown extraordinary sensitivity for uniaxial strains, which originates from graphene's unique electrical and mechanical properties and thinness [1]. This work compares through both theory and experiment the effect of cavity shape and size on the sensitivity of piezoresistive pressure sensors based on suspended graphene membranes. Further, the paper analyzes the effect of both biaxial and uniaxial strain on the membranes. Previous studies examined uniaxial strain through the fabrication of long, rectangular cavities. The present work uses circular cavities of varying sizes in order to obtain data from biaxially strained graphene membranes. QC 20140521

This paper reports a fabrication approach for very high aspect ratio through silicon vias (TSVs). The metal filling of the through via holes is implemented by adapting standard wire bonding technology. TSVs with a diameter of 30 μm and aspect ratios between 10:1 and 20:1 have been fabricated. Basic electrical characterization and optical inspection have been conducted to verify the resistance and integrity of the metal and insulator filling of the TSV. QC 20131007

This paper presents a packaging approach for inertial sensors using wire bonding technology. The die is mounted exclusively by bond wires on the front- and backside to the package. Conventional single-side die attach to substrates, such as gluing, is abandoned. The approach is characterized by its novel and symmetric die attach concept as well as its simplicity of applying a standard wire bonding process. The wire bond attachment facilitates significant reduction of thermally induced mechanical stresses. The attachment concept is characterized in terms of attachment stiffness and potential die resonances using Laser Doppler Vibrometry(LDV). White-light interferometry is used to investigate stress related warping that is induced by the die attachment process. QC 20131030

The protein auxilin is a coat component of brain clathrin-coated vesicles. It interacts directly with the heavy chain of clathrin and supports its assembly into regular cages [Ahle, S. & Ungewickell, E. (1990) J. Cell Biol. 111, 19–29]. The combined open reading frames of three cow brain cDNA clones with a total of 4531 nucleotides predict a molecular mass of 99 504 Da for auxilin. The coding region is followed by a very long untranslated region of at least 1670 nucleotides. By Northern analysis, auxilin transcripts are found only in brain tissue. Auxilin is not related to any of the previously sequenced clathrin-binding proteins, but the region of positions 50–350 is 29% identical (similarity 56%) to the corresponding region of the actin-binding protein tensin from chicken fibroblasts. Recombinant auxilin expressed in and purified from bacteria by affinity chromatography is functional with respect to clathrin binding.

This paper reports on a novel technique for the integration of NiTi shape memory alloy wires and other non-bondable wire materials into silicon-based microelectromechanical system structures using a standard wire-bonding tool. The efficient placement and alignment functions of the wire-bonding tool are used to mechanically attach the wire to deep-etched silicon anchoring and clamping structures. This approach enables a reliable and accurate integration of wire materials that cannot be wire bonded by traditional means. QC 20120528

This paper reports on the first integration of SMA wires into silicon based MEMS structures using a standard wire bonder. This approach allows fast and efficient placement, alignment and mechanical attachment of NiTi-based SMA wires to silicon-based MEMS. The wires are mechanically anchored and clamped into deep-etched silicon structures on a wafer. The placement precision is high with an average deviation of 4 #x03BC;m and the mechanical clamping is strong, allowing successful actuation of the SMA wires. © 2011 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.QC 20111110

Binding of AP180 to clathrin triskelia induces their assembly into 60-70 nm coats. The largest rat brain cDNA clone isolated predicts a molecular weight of 91,430 for AP180. Two cDNA clones have an additional small 57 bp insert. The deduced molecular weight agrees with gel filtration results provided the more chaotropic denaturant 6 M guanidinium thiocyanate is substituted for the weaker guanidinium chloride. The sequence and the proteolytic cleavage pattern suggest a three domain structure. The N-terminal 300 residues (pI 8.7) harbour a clathrin binding site. An acidic middle domain (pI 3.6, 450 residues), interrupted by an uncharged alanine rich segment of 59 residues, appears to be responsible for the anomalous physical properties of AP180. The C-terminal domain (166 residues) has a pI of 10.4. AP180 mRNA is restricted to neuronal sources. AP180 shows no significant homology to known clathrin binding proteins, but is nearly identical to a mouse phosphoprotein (F1-20). This protein, localized to synaptic termini, has so far been of unknown function.

Metachromatic leukodystrophy (MLD) is a lysosomal storage disease caused by a deficiency of the lysosomal enzyme arylsulfatase A (ASA). Enzyme replacement therapy (ERT) is a therapeutic option for MLD and other lysosomal disorders. This therapy depends on N-linked oligosaccharide-mediated delivery of intravenously injected recombinant enzyme to the lysosomes of patient cells. Because of the importance of N-linked oligosaccharide side chains in ERT, we examined the composition of the three N-linked glycans of four different recombinant ASAs in a site-specific manner. Depending on the culture conditions and the cell line expressing the enzyme, we detected a high variability of the high-mannose-type N-glycans which prevail at all glycosylation sites. Our data show that the composition of the glycans is largely determined by substantial trimming in the medium. The susceptibility for trimming is different for the glycans at the three N-glycosylation sites. Interestingly, which of the glycans is most susceptible to trimming also depends on production conditions. CHO cells cultured under bioreactor conditions yielded recombinant ASA with the most preserved N-glycan structures, the highest mannose-6-phosphate content and the highest similarity to non-recombinant enzyme. Notably, roughly one-third of the N-glycans released from the three glycosylation sites were fucosylated. In the last years, numerous recombinant lysosomal enzymes were used for preclinical ERT trials. Our data show that the oligosaccharide structures were very different in these trials making it difficult to draw common conclusions from the various investigations.

A deficiency of arylsulfatase A (ASA) causes the lysosomal storage disease metachromatic leukodystrophy, which is characterized by accumulation of the sphingolipid 3-O-sulfogalactosylceramide (sulfatide). Sphingolipid storage results in progressive demyelination and severe neurologic symptoms. The disease is lethal, and curative therapy is not available. To assess the therapeutic potential of enzyme replacement therapy (ERT), ASA knockout mice were treated by intravenous injection of recombinant human ASA. Plasma levels of ASA declined with a half-time of approximately 40 min, and enzyme was detectable in tissues within minutes after injection. The uptake of injected enzyme was high into liver, moderate into peripheral nervous system (PNS) and kidney and very low into brain. The apparent half-life of endocytosed enzyme was approximately 4 days. A single injection led to a time- and dose-dependent decline of the excess sulfatide in PNS and kidney by up to 70%, but no reduction was seen in brain. Four weekly injections with 20 mg/kg body weight not only reduced storage in peripheral tissues progressively, but also were surprisingly effective in reducing sulfatide storage in brain and spinal cord. The histopathology of kidney and central nervous system was ameliorated. Improved neuromotor coordination capabilities and normalized peripheral compound motor action potential demonstrate the benefits of ERT on the nervous system function. Enzyme replacement may therefore be a promising therapeutic option in this devastating disease.

The identification of phosphorylation sites is essential for a full understanding of the cellular functions of proteins. However, mass spectrometric analysis is often hampered by the low abundance of phosphoproteins, the difficulty of obtaining full sequence coverage by specific proteolysis reactions, and the low ionization efficiency of phosphopeptides compared with their non-phosphorylated analogs. In the present work a beta-elimination/Michael addition was used to replace the phosphate groups of pSer or pThr by a group which gives rise to an enhanced ionization efficiency. In order to find optimum reaction conditions, beta-elimination/Michael addition was examined using phosphorylated model peptides. Whereas complete elimination of phosphate could be achieved by treatment with barium hydroxide in organic solvents such as ethanol or acetonitrile, the yield of the Michael adduct strongly depended on the nucleophile and the peptide sequence. Reaction with 2-phenylethanethiol, p-bromophenethylamine and ethylenediamine clearly resulted in products showing higher matrix-assisted laser desorption/ionization (MALDI) signal intensities compared with those of the corresponding phosphorylated precursors. The method was successfully used to identify phosphorylated sequences of ovalbumin and human Stat1 by in-gel derivatization with 2-phenylethanethiol and subsequent peptide mass fingerprint analysis of the trypsin digests.

Die Europaische Behorde fur Lebensmittelsicherheit hat polycyclische aromatische Kohlenwasserstoffe in der Nahrung neu bewertet und eine Liste von 16 PAK vorgelegt, die zukunftig in Lebensmitteln zu bestimmen sind. Fur die quantitative Analyse bietet sich die GC/MS an.

Eukaryotic 70 kDa heat shock proteins (Hsp70s) are localized in various cellular compartments and exhibit functions such as protein translocation across membranes, protein folding and assembly. Here we demonstrate that the constitutively expressed members of the yeast cytoplasmic Ssa subfamily, Ssa1/2p, are involved in the transport of the vacuolar hydrolase aminopeptidase 1 from the cytoplasm into the vacuole. The Ssap family members displayed overlapping functions in the transport of aminopeptidase 1. In SSAI and SSAII deletion mutants the precursor of aminopeptidase 1 accumulated in a dodecameric complex that is packaged in prevacuolar transport vesicles. Ssa1/2p was prominently localized to the vacuolar membrane, consistent with the role we propose for Ssa proteins in the fusion of transport vesicles with the vacuolar membrane.

The instrument, Lumi-lmager was developed for the detection and accurate quantification of chemiluminescent signals on blots and in microtiter plates. It contains a cooled CCD camera, a specially developed lens system and software. In addition to luminescence, Lumi-lmager can also detect and quantify UV-excited fluorescent signals in gels. Here we describe the components and features of this instrument, as well as some of its applications.

Emp47p is a yeast Golgi transmembrane protein with a retrograde, Golgi to ER transport di-lysine signal in its cytoplasmic tail. Emp47p has previously been shown to recycle between the Golgi complex and the ER and to require its di-lysine signal for Golgi localization. In contrast to other proteins with di-lysine signals, the Golgi-localization of Emp47p has been shown to be preserved in ret1-1 cells expressing a mutant alpha-COP subunit of coatomer. Here we demonstrate by sucrose gradient fractionation and immunofluorescence analysis that recycling of Emp47p was unimpaired in ret1-1. Furthermore we have characterized three new alleles of ret1 and showed that Golgi localization of Emp47p was intact in cells with those mutant alleles. We could correlate the ongoing recycling of Emp47p in ret1-1 with preserved in vitro binding of coatomer from ret1-1 cells to immobilized GST-Emp47p-tail fusion protein. As previously reported, the di-lysine signal of Wbp1p was not recognized by ret1-1 mutant coatomer, suggesting a possible role for alpha-COP in the differential binding to distinct di-lysine signals. In contrast to results with alpha-COP mutants, we found that Emp47p was mislocalised to the vacuole in mutants affecting beta'-, gamma-, delta-, and zeta-COP subunits of coatomer and that the mutant coatomer bound neither to the Emp47p nor to the Wbp1p di-lysine signal in vitro. Therefore, the retrograde transport of Emp47p displayed a differential requirement for individual coatomer subunits and a special role of alpha-COP for a particular transport step in vivo.Emp47p is a yeast Golgi transmembrane protein with a retrograde, Golgi to ER transport di-lysine signal in its cytoplasmic tail. Emp47p has previously been shown to recycle between the Golgi complex and the ER and to require its di-lysine signal for Golgi localization. In contrast to other proteins with di-lysine signals, the Golgi-localization of Emp47p has been shown to be preserved in ret1-1 cells expressing a mutant alpha-COP subunit of coatomer. Here we demonstrate by sucrose gradient fractionation and immunofluorescence analysis that recycling of Emp47p was unimpaired in ret1-1. Furthermore we have characterized three new alleles of ret1 and showed that Golgi localization of Emp47p was intact in cells with those mutant alleles. We could correlate the ongoing recycling of Emp47p in ret1-1 with preserved in vitro binding of coatomer from ret1-1 cells to immobilized GST-Emp47p-tail fusion protein. As previously reported, the di-lysine signal of Wbp1p was not recognized by ret1-1 mutant coatomer, suggesting a possible role for alpha-COP in the differential binding to distinct di-lysine signals. In contrast to results with alpha-COP mutants, we found that Emp47p was mislocalised to the vacuole in mutants affecting beta'-, gamma-, delta-, and zeta-COP subunits of coatomer and that the mutant coatomer bound neither to the Emp47p nor to the Wbp1p di-lysine signal in vitro. Therefore, the retrograde transport of Emp47p displayed a differential requirement for individual coatomer subunits and a special role of alpha-COP for a particular transport step in vivo.

Clathrin coated vesicles, which are present in probably all eukaryotes, are the agents for receptor mediated endocytosis and for the transport of lysosomal enzyme receptors from the trans-Golgi to the endosomal system (Goldstein et al 1985; Pearse and Bretscher, 1981). In neurons they are conjectured to facilitate also the recycling of synaptic vesicle membrane after neurotransmitter release (Heuser 1989). The functions of the coat components include the binding of specific cargo molecules (receptors), the coordinated assembly of the coat, its reorganization and eventually its dissolution. The emphasis in this report lies on structural and functional aspects of clathrin associated proteins present in coated vesicle populations from bovine brain.

Setaria viridis (L.) P. Beauv. and its domesticated form, S. italica (L.) P. Beauv., have been developed over the past few years as model systems for C4 photosynthesis and for the analysis of bioenergy traits. S. viridis is native to Eurasia, but is now a ubiquitous weed. An analysis of the population structure of a set of 232 S. viridis lines, mostly from North America but also comprising some accessions from around the world, using 11 SSR markers, showed that S. viridis populations in the US largely separate by latitude and/or climatic zone. S. viridis populations from the Northern US and Canada (north of 44°N) group with accessions from Western Europe, while populations in the Mid and Southern US predominantly group with accessions from Turkey and Iran. We hypothesize that S. viridis in the US was most likely introduced from Europe, and that introductions were competitive only in regions that had climatic conditions that were similar to those in the regions of origins. This hypothesis is supported by the fact that Canadian S. viridis lines were fast cycling and undersized when grown in the Mid-Western and Southern US compared to their morphology in their native environment. A comparison of the population structure obtained with 11 SSR markers and ~40,000 single nucleotide polymorphisms (SNPs) in a common set of S. viridis germplasm showed that both methods essentially yielded the same groupings, although admixture was identified at a higher frequency in the SNP analysis. Small numbers of SSR markers can thus be used effectively to discern the population structure in this inbreeding species.

GPI-anchored proteins are attached to the membrane via a glycosylphosphatidylinositol-(GPI) anchor whose carbohydrate core is conserved in all eukaryotes. Apart from membrane attachment, the precise role of the GPI-anchor is not known, but it has been proposed to play a role in protein sorting. We have investigated the transport of the yeast GPI-anchored protein Gas1p. We identified two mutant strains involved in very different cellular processes that are blocked selectively in the transport of GPI-anchored proteins before arrival to the Golgi. The end8-1/lcb1-100 mutant is defective in ceramide synthesis. In vitro data suggest a requirement for ceramides after the exit from the ER. We therefore propose that ceramides might function in the fusion of a GPI-containing vesicle with the Golgi, but we cannot exclude a role in the ER. The second mutant that blocks the transport of GPI-anchored proteins to the Golgi is ret1-1, a mutant in the alpha-subunit of coatomer. In both mutants, GPI-anchor attachment is normal and in ret1-1 cells, the GPI-anchors are remodeled with ceramide to the same extent as in wild-type cells.