244 research outputs found
Expression of the protein inhibitor of nitric oxide synthase in the adult rat retina before and after optic nerve lesion
No full textThe molecular messenger nitric oxide (NO) not only serves a number of physiologic functions, but is also involved in the pathophysiology of neurodegeneration. It is produced by the nitric oxide synthase (NOS) isoenzymes. One of the many players regulating NOS activity is the Protein Inhibitor of NOS, PIN. To gain further insight into the mechanisms of NOS regulation and NO-mediated cell death after nerve trauma, we examined PIN expression in a standard model of lesion-induced neurodegeneration, the rat optic nerve transsection model. In both the axotomized retinae and the control retinae PIN expression was predominantly observed in the retinal ganglion cell layer. Optic nerve lesion did neither change the amount of PIN mRNA, as determined by in situ hybridization and real-time RT-PCR, nor did it change the amount of PIN as determined by immunohistochemistry and Western blot analysis. These results suggest that in our model, NOS activity is not regulated by altered PIN levels, which contributes to our understanding of apoptotic mechanisms in injured neurons. (c) 2005 Elsevier B.V. All rights reserved
Brain-derived neurotrophic factor-mediated neuroprotection of adult rat retinal ganglion cells in vivo does not exclusively depend on phosphatidyl-inositol-3 '-kinase/protein kinase B signaling
No full textThe neurotrophin brain-derived neurotrophic factor (BDNF) serves as a survival, mitogenic, and differentiation factor in both the developing and adult CNS and PNS. In an attempt to identify the molecular mechanisms underlying BDNF neuroprotection, we studied activation of two potentially neuroprotective signal transduction pathways by BDNF in a CNS trauma model. Transection of the optic nerve (ON) in the adult rat induces secondary death of retinal ganglion cells (RGCs). Repeated intraocular injections of BDNF prevent the degeneration of RGCs 14 d after ON lesion most likely by inhibition of apoptosis. Here, we report that BDNF activates both protein kinase B (PKB) via a phosphatidyl-inositol-3'-kinase (PI-3-K)-dependent mechanism and the mitogen-activated protein kinases extracellular signal-regulated kinase 1 (ERK1) and ERK2. Furthermore, we provide evidence that BDNF suppresses cleavage and enzymatic activity of the neuronal cell death effector caspase-3. Distinct from our recent study in which inhibition of the PI-3-K/PKB pathway attenuated the survival-promoting action of insulin-like growth factor-I on axotomized RGCs (Kermer et al., 2000), it does not in the case of BDNF. Thus, we assume that BDNF does not depend on a single signal transduction pathway exerting its neuroprotective effects on lesioned CNS neurons
C-H functionalisation of aldehydes using light generated, non-stabilised diazo compounds in flow
No full textThe difficulty in accessing and safely utilising non-stabilised diazo species has in the past limited the application of this class of compounds. Here we explore further the use of oxadiazolines, non-stabilised diazo precursors which are bench stable, in direct, non-catalytic, aldehyde C-H functionalisation reactions under UV photolysis in flow and free from additives. Commercially available aldehydes are coupled to afford unsymmetrical aryl-alkyl and alkyl-alkyl ketones while mild conditions and lack of transition metal catalysts allow for exceptional functional group tolerance. Examples are given on small scale and in a larger scale continuous production.</p
Factors influencing visual landscape quality perceived by the public. Results from a national survey
No full textFunding Information: The authors acknowledge funding from the Federal Office of the Environment (FOEN) through the Swiss Landscape Monitoring Programme (LABES). Dr. Chris Stride provided statistical consultancy through figure it out on earlier versions of our multilevel model and made helpful suggestions on model improvements. Any mistakes are our own. We gratefully acknowledge the constructive feedback from three anonymous reviewers, which helped to improve our manuscript. Publisher Copyright: © 2020 The Author(s) Copyright: Copyright 2021 Elsevier B.V., All rights reserved.Peer reviewe
Activation of annexin A1 signalling in renal fibroblasts exerts antifibrotic effects
No full textAimThe anti-inflammatory protein annexin A1 (AnxA1) and its formyl peptide receptor 2 (FPR2) have protective effects in organ fibrosis. Their role in chronic kidney disease (CKD) has not yet been elucidated. Our aim was to characterize the AnxA1/FPR2 system in models of renal fibrosis. MethodsRats were treated with angiotensin receptor antagonist during the nephrogenic period (ARAnp) to induce late-onset hypertensive nephropathy and fibrosis. Localization and regulation of AnxA1 and FPR2 were studied by quantitative real-time PCR and double labelling immunofluorescence. Biological effects of AnxA1 were studied in cultured renal fibroblasts from AnxA1(-/-) and wild-type mice. ResultsAngiotensin receptor antagonist during the nephrogenic period kidneys displayed matrix foci containing CD73(+) fibroblasts, alpha-smooth muscle actin (a-SMA)(+) myofibroblasts and CD68(+) macrophages. TGF- and AnxA1 mRNAs were similar to threefold higher than in controls. AnxA1 was localized to macrophages and fibroblasts; myofibroblasts were negative. FPR2 was localized to fibroblasts, myofibroblasts, macrophages and endothelial cells. AnxA1 and FPR2 immunoreactive signals were increased in the foci, with fibroblasts and macrophages expressing both proteins. AnxA1(-/-) fibroblasts revealed higher -SMA (sevenfold) and collagen 1A1 (Col1A1; 144-fold) mRNA levels than controls. Treatment of murine WT fibroblasts with TGF- (22.5ngmL24h(-1)) increased mRNA levels of -SMA (9.3-fold) and Col1A1 (fourfold). These increases were greatly attenuated upon overexpression of AnxA1 (1.5- and 1.7-fold, respectively; P<0.05). Human fibroblasts reacted similarly when receiving the FPR2 inhibitor WRW4. ConclusionOur results demonstrate that AnxA1 and FPR2 are abundantly expressed in the renal interstitium and modulate fibroblast phenotype and extracellular matrix synthesis activity
The thermodynamics of the palladium hydrogen system
No full textP-T- ( = composition) isobars have been measured using an equilibrate-quench-analyze technique. The metal samples were single crystals of super-pure palladium. It has been found that, in the composition range investigated, the partial thermodynamic functions of the dissolved H-atoms did not depend on composition. However, a strong temperature dependence was found. The present results are in excellent agreement with previous measurements using polycrystalline Pd at high temperatures, but strong deviations are found at low temperatures
Biotechnological Production of Carotenoids by Aquatic Microorganisms
No full textPopulation growth, higher expectations for a long and healthy life, and climate change are currently major drivers for the development and production of health-promoting, sustainable, and climate-friendly substances. A particular focus is on the food and pharmaceutical sectors, as these directly impact human health. This progress led to an increase in demand for additives improving the properties of food and feed. In this context, carotenoids play an important role. They comprise a group of natural pigments, which are used to color food and feed. The biotechnological production enables a sustainable supply of natural carotenoids, but there is still room for improvements in manufacturing processes. The aim of this work was to support the further development of the biotechnological production of carotenoids by optimizing methods and processes and by searching for new, promising production organisms: 1. The development of a method for the determination of astaxanthin from Haematococcus pluvialis helped to find a good compromise between simple and fast but also accurate measurement procedures. 2. The application of the developed method in the optimization of the downstream process of astaxanthin from H. pluvialis aimed to maximize astaxanthin yield while minimizing process costs and energy consumption. 3. The screening of a Thraustochytriaceae strain collection indicated that some strains are potentially suitable for a sustainable production of carotenoids. The gained comprehensive understanding is essential to improve the necessary production of carotenoids through optimized synthesis and processing, to enable targeted and economical use, and thus to make a lasting contribution to public health and climate protection
Observation of Pyroelectricity in Chiral Smectic-C and -H Liquid Crystals
No full textPyroelectricity has been observed in the smectic-C and smectic-H phases of l-p-decyloxybenzylidene-p′-amino-2-methylbutylcinnamate after the material is poled in a dc field. The observed pyroelectric coefficient is consistent with an estimate of its theoretical value.SCI紙本電子
The Effect Of The Utilization Of Transportable Facilities Upon Pupil Achievement And Teacher Morale.
No full textPhDSchool administrationUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/187013/2/7214918.pd
UV/Vis and SIR chromatograms of an enzymolyzed <i>H</i>. <i>pluvialis</i> extract and corresponding absorption spectra of astaxanthin diastereomers.
No full textUV/Vis and SIR chromatograms of an enzymolyzed H. pluvialis extract and corresponding absorption spectra of astaxanthin diastereomers.</p
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