85 research outputs found

    Research on Layer Manufacturing Techniques at Fraunhofer

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    Within the German Fraunhofer-Gesellschaft, the Fraunhofer Alliance Rapid Prototyping unites the competences of 12 institutes in the field of solid freeform fabrication. Covered competences are virtual and computer-aided product planning methods and techniques, the development and integration of materials and processes for different industrial sectors. This paper presents actual research results on layer manufacturing within the Fraunhofer- Gesellschaft based on examples from Fraunhofer ILT »Laser Melting - Direct manufacturing of metal parts with unique properties«, Fraunhofer IFAM »ecoMold - A novel concept to produce molds for plastic injection molding and pressure die casting« and Fraunhofer IPT »Quick manufacture, repair and modification of steel molds using Controlled Metal Build Up (CMB)«.Mechanical Engineerin

    Metabolic fate, mass spectral fragmentation, detectability, and differentiation in urine of the benzofuran designer drugs 6-APB and 6-MAPB in comparison to their 5-isomers using GC-MS and LC-(HR)-MSn techniques

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    The number of so-called new psychoactive substances (NPS) is still increasing by modification of the chemical structure of known (scheduled) drugs. As analogues of amphetamines, 2-aminopropyl-benzofurans were sold. They were consumed because of their euphoric and empathogenic effects. After the 5-(2-aminopropyl)benzofurans, the 6-(2-aminopropyl)benzofuran isomers appeared. Thus, the question arose whether the metabolic fate, the mass spectral fragmentation, and the detectability in urine are comparable or different and how an intake can be differentiated. In the present study, 6-(2-aminopropyl)benzofuran (6-APB) and its N-methyl derivative 6-MAPB (N-methyl-6-(2-aminopropyl)benzofuran) were investigated to answer these questions. The metabolites of both drugs were identified in rat urine and human liver preparations using GC-MS and/or liquid chromatography-high resolution-mass spectrometry (LC-HR-MSn). Besides the parent drug, the main metabolite of 6-APB was 4-carboxymethyl-3-hydroxy amphetamine and the main metabolites of 6-MAPB were 6-APB (N-demethyl metabolite) and 4-carboxymethyl-3-hydroxy methamphetamine. The cytochrome P450 (CYP) isoenzymes involved in the 6-MAPB N-demethylation were CYP1A2, CYP2D6, and CYP3A4. An intake of a common users’ dose of 6-APB or 6-MAPB could be confirmed in rat urine using the authors’ GC-MS and the LC-MSn standard urine screening approaches with the corresponding parent drugs as major target allowing their differentiation. Furthermore, a differentiation of 6-APB and 6-MAPB in urine from their positional isomers 5-APB and 5-MAPB was successfully performed after solid phase extraction and heptafluorobutyrylation by GC-MS via their retention times

    Expression of TRPC6 channels in human epithelial breast cancer cells

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    <p>Abstract</p> <p>Background</p> <p>TRP channels have been shown to be involved in tumour generation and malignant growth. However, the expression of these channels in breast cancer remains unclear. Here we studied the expression and function of endogenous TRPC6 channels in a breast cancer cell line (MCF-7), a human breast cancer epithelial primary culture (hBCE) and in normal and tumour breast tissues.</p> <p>Methods</p> <p>Molecular (Western blot and RT-PCR), and immunohistochemical techniques were used to investigate TRPC6 expression. To investigate the channel activity in both MCF-7 cells and hBCE we used electrophysiological technique (whole cell patch clamp configuration).</p> <p>Results</p> <p>A non selective cationic current was activated by the oleoyl-2-acetyl-sn-glycerol (OAG) in both hBCE and MCF-7 cells. OAG-inward current was inhibited by 2-APB, SK&F 96365 and La<sup>3+</sup>. TRPC6, but not TRPC7, was expressed both in hBCE and in MCF-7 cells. TRPC3 was only expressed in hBCE. Clinically, TRPC6 mRNA and protein were elevated in breast carcinoma specimens in comparison to normal breast tissue. Furthermore, we found that the overexpression of TRPC6 protein levels were not correlated with tumour grades, estrogen receptor expression or lymph node positive tumours.</p> <p>Conclusion</p> <p>Our results indicate that TRPC6 channels are strongly expressed and functional in breast cancer epithelial cells. Moreover, the overexpression of these channels appears without any correlation with tumour grade, ER expression and lymph node metastasis. Our findings support the idea that TRPC6 may have a role in breast carcinogenesis.</p

    TRPV6 Determines the Effect of Vitamin D3 on Prostate Cancer Cell Growth

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    Despite remarkable advances in the therapy and prevention of prostate cancer it is still the second cause of death from cancer in industrialized countries. Many therapies initially shown to be beneficial for the patients were abandoned due to the high drug resistance and the evolution rate of the tumors. One of the prospective therapeutical agents even used in the first stage clinical trials, 1,25-dihydroxyvitamin D3, was shown to be either unpredictable or inefficient in many cases. We have already shown that TRPV6 calcium channel, which is the direct target of 1,25-dihydroxyvitamin D3 receptor, positively controls prostate cancer proliferation and apoptosis resistance (Lehen'kyi et al., Oncogene, 2007). However, how the known 1,25-dihydroxyvitamin D3 antiproliferative effects may be compatible with the upregulation of pro-oncogenic TRPV6 channel remains a mystery. Here we demonstrate that in low steroid conditions 1,25-dihydroxyvitamin D3 upregulates the expression of TRPV6, enchances the proliferation by increasing the number of cells entering into S-phase. We show that these pro-proliferative effects of 1,25-dihydroxyvitamin D3 are directly mediated via the overexpression of TRPV6 channel which increases calcium uptake into LNCaP cells. The apoptosis resistance of androgen-dependent LNCaP cells conferred by TRPV6 channel is drastically inversed when 1,25-dihydroxyvitamin D3 effects were combined with the successful TRPV6 knockdown. In addition, the use of androgen-deficient DU-145 and androgen-insensitive LNCaP C4-2 cell lines allowed to suggest that the ability of 1,25-dihydroxyvitamin D3 to induce the expression of TRPV6 channel is a crucial determinant of the success or failure of 1,25-dihydroxyvitamin D3-based therapies

    Interdomain Interactions Control Ca2+-Dependent Potentiation in the Cation Channel TRPV4

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    Several Ca2+-permeable channels, including the non-selective cation channel TRPV4, are subject to Ca2+-dependent facilitation. Although it has been clearly demonstrated in functional experiments that calmodulin (CaM) binding to intracellular domains of TRP channels is involved in this process, the molecular mechanism remains elusive. In this study, we provide experimental evidence for a comprehensive molecular model that explains Ca2+-dependent facilitation of TRPV4. In the resting state, an intracellular domain from the channel N terminus forms an autoinhibitory complex with a C-terminal domain that includes a high-affinity CaM binding site. CaM binding, secondary to rises in intracellular Ca2+, displaces the N-terminal domain which may then form a homologous interaction with an identical domain from a second subunit. This represents a novel potentiation mechanism that may also be relevant in other Ca2+-permeable channels

    Signal transduction-related responses to phytohormones and environmental challenges in sugarcane

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    BACKGROUND: Sugarcane is an increasingly economically and environmentally important C4 grass, used for the production of sugar and bioethanol, a low-carbon emission fuel. Sugarcane originated from crosses of Saccharum species and is noted for its unique capacity to accumulate high amounts of sucrose in its stems. Environmental stresses limit enormously sugarcane productivity worldwide. To investigate transcriptome changes in response to environmental inputs that alter yield we used cDNA microarrays to profile expression of 1,545 genes in plants submitted to drought, phosphate starvation, herbivory and N(2)-fixing endophytic bacteria. We also investigated the response to phytohormones (abscisic acid and methyl jasmonate). The arrayed elements correspond mostly to genes involved in signal transduction, hormone biosynthesis, transcription factors, novel genes and genes corresponding to unknown proteins. RESULTS: Adopting an outliers searching method 179 genes with strikingly different expression levels were identified as differentially expressed in at least one of the treatments analysed. Self Organizing Maps were used to cluster the expression profiles of 695 genes that showed a highly correlated expression pattern among replicates. The expression data for 22 genes was evaluated for 36 experimental data points by quantitative RT-PCR indicating a validation rate of 80.5% using three biological experimental replicates. The SUCAST Database was created that provides public access to the data described in this work, linked to tissue expression profiling and the SUCAST gene category and sequence analysis. The SUCAST database also includes a categorization of the sugarcane kinome based on a phylogenetic grouping that included 182 undefined kinases. CONCLUSION: An extensive study on the sugarcane transcriptome was performed. Sugarcane genes responsive to phytohormones and to challenges sugarcane commonly deals with in the field were identified. Additionally, the protein kinases were annotated based on a phylogenetic approach. The experimental design and statistical analysis applied proved robust to unravel genes associated with a diverse array of conditions attributing novel functions to previously unknown or undefined genes. The data consolidated in the SUCAST database resource can guide further studies and be useful for the development of improved sugarcane varieties

    A Development Consensus reconciling the Beijing Model and Washington Consensus: Views and Agenda

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    Reconciling the two dominant development models of the Washington Consensus (WC) and Beijing Model (BM) remains a critical challenge in the literature. The challenge is even more demanding when emerging development paradigms like the Liberal Institutional Pluralism (LIP) and New Structural Economics (NSE) schools have to be integrated. While the latter has recognized both State and market failures but failed to provide a unified theory, the former has left the challenging concern of how institutional diversity matter in the development process. We synthesize perspectives from over 150 recently published papers on development and Sino-African relations in order to present the relevance of both the WC and BM in the long-term and short-run respectively. While the paper provides a unified theory by reconciling the WC and the BM to complement the NSE, it at the same time presents a case for economic rights and political rights as short-run and long-run development priorities respectively. By reconciling the WC with the BM, the study contributes at the same to macroeconomic NSE literature of unifying a development theory and to the LIP literature on institutional preferences with stages of development. Hence, the proposed reconciliation takes into account the structural and institutional realities of nations at difference stages of the process of development

    Reinventing foreign aid for inclusive and sustainable development: a survey

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    This survey essay reviews over 200 papers in arguing that in order to achieve sustainable and inclusive development, foreign aid should not orient developing countries towards industrialisation in the perspective of Kuznets but in the view of Piketty. Abandoning the former’s view that inequality will fall with progress in industrialisation and placing more emphasis on inequality in foreign aid policy will lead to more sustainable development outcomes. Inter alia: mitigate short-term poverty; address concerns of burgeoning population growth; train recipient governments on inclusive development; fight corruption and mismanagement and; avoid the shortfalls of celebrated Kuznets’ conjectures. We discuss how the essay addresses post-2015 development challenges and provide foreign aid policy instruments with which discussed objectives can be achieved. In summary, the essay provides useful policy measures to avoid past pitfalls. ‘Output may be growing, and yet the mass of the people may be becoming poorer’ (Lewis, 1955). ‘Lewis led all developing countries to water, proverbially speaking, some African countries have so far chosen not to drink’ (Amavilah, 2014). Piketty (2014) has led all developing countries to the stream again and a challenging policy syndrome of our time is how foreign aid can help them to drink
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