Publications by authors named "Vestling M"

Current methods to isolate synaptic vesicles (SVs), the organellar quanta of synaptic transmission, require highly specialized materials and up to 24 h. These technical obstacles have thus far limited the study of SVs in models of synaptic function and pathophysiology. Here, we describe techniques for the rapid isolation of SVs by immunoprecipitation with widely available antibodies conjugated to magnetic beads.

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Synthesis of proanthocyanidin-cinnamaldehydes pyrylium products (PCPP) was achieved by the condensation reaction of proanthocyanidins (PAC) with cinnamaldehyde and four cinnamaldehyde derivatives. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) spectra of PCPP show masses that correspond to (epi)catechin oligomers attached to single, double, or triple moieties of cinnamaldehydes. Synthesized PCPP exhibited fluorescence at higher excitation and emission wavelengths than PAC.

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Background: Cranberry proanthocyanidins (c-PAC) are oligomeric structures of flavan-3-ol units, which possess A-type interflavan bonds. c-PAC differs from other botanical sources because other PAC mostly have B-type interflavan bonds. Cranberry products used to alleviate and prevent urinary tract infections may suffer from adulteration, where c-PAC are replaced with less expensive botanical sources of PAC that contain B-type interflavan bonds.

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Proanthocyanidin (PAC) profiles of apples (a-PAC), cranberries (c-PAC), and peanut skins (p-PAC) were determined by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). Deconvolution of overlapping isotopic patterns indicated that in apples, only 5% of the PAC oligomers contain one or more A-type bonds, whereas in cranberries and peanut skins, 96% of the PAC oligomers contain one or more A-type bonds. MALDI-TOF MS data combined with multivariate analysis, such as principal component analysis (PCA) and linear discriminant analysis (LDA), were used to differentiate and discriminate a-PAC, c-PAC, and p-PAC from one another.

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Neuropeptides can have significant effects on neurons and synapses, but among the ∼250 predicted peptides in nematodes, few have been characterized functionally. Here, we report new neuropeptides in the 4 RME nerve ring motorneurons of the nematode Ascaris suum. These GABAergic neurons are involved in three-dimensional head movement.

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A complementary application of three analytical techniques, viz. multidimensional nuclear magnetic resonance spectroscopy (NMR), mass spectrometry (MS), and single-crystal X-ray diffractometry was required to identify and refine two natural products isolated from Millettia versicolor and solvent of crystallization. The two compounds, namely 3-(2H-1,3-benzodioxol-5-yl)-6-methoxy-8,8-dimethyl-4H,8H-pyrano[2,3-h]chromen-4-one, or durmillone, (I), and (2E)-1-(4-{[(2E)-3,7-dimethylocta-2,6-dien-1-yl]oxy}-2-hydroxyphenyl)-3-(4-hydroxyphenyl)prop-2-en-1-one, (II), could not be separated by routine column chromatography and cocrystallized in a 2:1 ratio with 0.

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In this work we characterize the interaction of pomegranate hydrolyzable tannins (HT) with hen egg-white lysozyme (HEL) and determine the effects of non-covalent tannin-protein complexes on macrophage endocytosis, processing and presentation of antigen. We isolated HT from pomegranate and complex to HEL, the resulting non-covalent tannin-protein complex was characterized by gel electrophoresis and MALDI-TOF MS. Finally, cell culture studies and confocal microscopy imaging were conducted on the non-covalent pomegranate HT-HEL protein complexes to evaluate its effect on macrophage antigen uptake, processing and presentation to T-cell hybridomas.

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Neuromodulators have become an increasingly important component of functional circuits, dramatically changing the properties of both neurons and synapses to affect behavior. To explore the role of neuropeptides in Ascaris suum behavior, we devised an improved method for cleanly dissecting single motorneuronal cell bodies from the many other cell processes and hypodermal tissue in the ventral nerve cord. We determined their peptide content using matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry (MS).

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Neuropeptides are known to have dramatic effects on neurons and synapses; however, despite extensive studies of the motorneurons in the parasitic nematode Ascaris suum, their peptide content had not yet been described. We determined the peptide content of single excitatory motorneurons by mass spectrometry and tandem mass spectrometry. There are two subsets of ventral cord excitatory motorneurons, each with neuromuscular output either anterior or posterior to their cell body, mediating forward or backward locomotion, respectively.

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A novel methodology was developed to elucidate proanthocyanidins (PAC) interaction with extra-intestinal pathogenic Escherichia coli (ExPEC). PAC inhibit ExPEC invasion of epithelial cells and, therefore, may prevent transient gut colonization, conferring protection against subsequent extra-intestinal infections, such as urinary tract infections. Until now PAC have not been chemically labeled with fluorophores.

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Antibodies that preferentially and specifically target pathological oligomeric protein and peptide assemblies, as opposed to their monomeric and amyloid counterparts, provide therapeutic and diagnostic opportunities for protein misfolding diseases. Unfortunately, the molecular properties associated with oligomer-specific antibodies are not well understood, and this limits targeted design and development. We present here a generic method that enables the design and optimisation of oligomer-specific antibodies.

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We utilized three independent techniques, immunocytochemistry (ICC), single cell mass spectrometry (MS), and in situ hybridization (ISH), to localize neuropeptides and their transcripts in the nervous system of the nematode Ascaris suum . AF11 (SDIGISEPNFLRFa) is an endogenous peptide with potent paralytic effects on A. suum locomotory behavior.

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Objective: The aim of this study was to increase the understanding of stroke survivors' thoughts and experiences from returning to work after stroke.

Methods: Semi-structured interviews were carried out with twelve persons, based on a thematic interview guide. A qualitative content analysis was performed.

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A method to deconvolute overlapping isotope patterns in positive mode matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) was developed to determine ratios of A- to B-type interflavan bonds in proanthocyanidins that were isolated from cranberry (Vaccinium macrocarpon, Ait.) press cake (c-PAC). Precision and accuracy was validated for binary mixtures of procyanidins A2 and B2.

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Neurodegeneration in protein-misfolding disease is generally assigned to toxic function of small, soluble protein aggregates. Largely, these assignments are based on observations of cultured neural cells where the suspect protein material is titrated directly into the growth medium. In the present study, we use this approach to shed light on the cytotoxic action of the metalloenzyme Cu/Zn superoxide dismutase 1 (SOD1), associated with misfolding and aggregation in amyotrophic lateral sclerosis (ALS).

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The addition of polyoxyethylene sorbitan monooleate (Tween 80) to a culture of mycobacteria greatly influences cell permeability and sensitivity to antibiotics but very little is known regarding the underlying mechanism. Here we show that Corynebacterium matruchotii (surrogate of mycobacteria) converts Tween 80 to a structural series of polyoxyethylenic acids which are then used to form novel series-2A and series-2B glycolipids. Minor series-3 glycolipids were also synthesized.

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Background: A functional link has been established between the severe neurodegenerative disorder Familial amyloidotic polyneuropathy and the enhanced propensity of the plasma protein transthyretin (TTR) to form aggregates in patients with single point mutations in the TTR gene. Previous work has led to the establishment of an experimental model based on transgenic expression of normal or mutant forms of human TTR in Drosophila flies. Remarkably, the severity of the phenotype was greater in flies that expressed a single copy than with two copies of the mutated gene.

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The multifaceted nature of Alzheimer's disease (AD) has led to the development of multi-targeted compounds based on the classical AD drug, tacrine, first known to inhibit the acetylcholine-degrading enzyme acetylcholinesterase (AChE). In the present work, we explore the potentiality of multimers of tacrine in this field. The synthesis using the so-called "click chemistry" and the in vitro study of the conjugates are described.

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Background: Alzheimers disease (AD) has been strongly linked to an anomalous self-assembly of the amyloid-β peptide (Aβ). The correlation between clinical symptoms of AD and Aβ depositions is, however, weak. Instead small and soluble Aβ oligomers are suggested to exert the major pathological effects.

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We have developed a method for dissecting single neurons from the nematode Ascaris suum, in order to determine their peptide content by mass spectrometry (MS). In this paper, we use MALDI-TOF MS and tandem MS to enumerate and sequence the peptides present in the two neurons, ALA and RID, that comprise the dorsal ganglion. We compare the peptide content determined by MS with the results of immunocytochemistry and in situ hybridization of previously isolated peptides AF2, AF8 and 6 peptides encoded by the afp-1 transcript.

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Alzheimer's disease, a neurodegenerative disorder causing synaptic impairment and neuronal cell death, is strongly correlated with aggregation of the amyloid-beta peptide (Abeta). Divalent metal ions such as Cu(2+) and Zn(2+) are known to significantly affect the rate of aggregation and morphology of Abeta assemblies in vitro and are also found at elevated levels within cerebral plaques in vivo. The present investigation characterized the architecture of the aggregated forms of Abeta(1-40) and Abeta(1-42) in the presence or absence of either Cu(2+) or Zn(2+) using quenched hydrogen/deuterium exchange combined with solution NMR spectroscopy.

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Objective: To examine the effect of using a mitt during shortened constraint-induced movement therapy for patients in the subacute phase after stroke.

Subjects: Twenty-four patients with stroke (mean age 57.6 (standard deviation (SD) 8.

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Familial amyloidotic polyneuropathy (FAP) is linked to destabilising point mutations in the human plasma protein transthyretin (TTR). Consistent with similar amyloid disorders, low molecular weight TTR oligomers have been shown to exert the major cytotoxic effect. The amyloid structure of TTR contains non-native inter-molecular disulphide linkages via the cysteine at position 10 (Cys10).

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Serine/threonine phosphorylation of the nonstructural protein 5 (NS5) is conserved feature of flaviviruses, but the kinase(s) responsible and function(s) remain unknown. Mass spectrometry was used to characterize phosphorylated residues of yellow fever virus (YFV) NS5 expressed in mammalian cells. Multiple different phosphopeptides were detected.

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Dynamic regulation of G-protein signaling in the phototransduction cascade ensures the high temporal resolution of vision. In a key step, the activated alpha-subunit of transducin (Galphat-GTP) activates the cGMP phosphodiesterase (PDE) by binding the inhibitory gamma-subunit (PDEgamma). Significant progress in understanding the interaction between Galphat and PDEgamma was achieved by solving the crystal structure of the PDEgamma C-terminal peptide bound to Galphat in the transition state for GTP hydrolysis (Slep, K.

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