MS.

Distribution by Scientific Domains

Kinds of MS.

  • maldi-tof ms.

  • Terms modified by MS.

  • ms. however
  • ms. in addition
  • ms. it
  • ms. there
  • ms. we

  • Selected Abstracts


    Insulin resistance and fuel homeostasis: the role of AMP-activated protein kinase

    ACTA PHYSIOLOGICA, Issue 1 2009
    B. D. Hegarty
    Abstract The worldwide prevalence of type 2 diabetes (T2D) and related disorders of the metabolic syndrome (MS) has reached epidemic proportions. Insulin resistance (IR) is a major perturbation that characterizes these disorders. Extra-adipose accumulation of lipid, particularly within the liver and skeletal muscle, is closely linked with the development of IR. The AMP-activated protein kinase (AMPK) pathway plays an important role in the regulation of both lipid and glucose metabolism. Through its effects to increase fatty acid oxidation and inhibit lipogenesis, AMPK activity in the liver and skeletal muscle could be expected to ameliorate lipid accumulation and associated IR in these tissues. In addition, AMPK promotes glucose uptake into skeletal muscle and suppresses glucose output from the liver via insulin-independent mechanisms. These characteristics make AMPK a highly attractive target for the development of strategies to curb the prevalence and costs of T2D. Recent insights into the regulation of AMPK and mechanisms by which it modulates fuel metabolism in liver and skeletal muscle are discussed here. In addition, we consider the arguments for and against the hypothesis that dysfunctional AMPK contributes to IR. Finally we review studies which assess AMPK as an appropriate target for the prevention and treatment of T2D and MS. [source]


    Validated protocol for FoxP3 reveals increased expression in type 1 diabetes patients,

    CYTOMETRY, Issue 2 2009
    Jean Grant
    Abstract Background FoxP3 has become a key identifier of regulatory T cells. Investigators have used a variety of antibodies and methods for detecting FoxP3 by flow cytometry. To standardize FoxP3 antibody staining for use in clinical trial samples, we tested various antibodies from different vendors, cell preparation protocols and fix/perm reagents, and cell isolation procedures. Using this optimized staining protocol, we evaluated clinical specimens from patients with multiple sclerosis (MS) or type 1 diabetes. Methods FoxP3 antibodies from eBioscience (236A/E7 and PCH101) and BioLegend (206D) were evaluated along with their respective methods and fix/perm reagents for preparation and staining of FoxP3 for flow cytometry. Fresh washed blood and frozen or fresh PBMC were evaluated. Upon optimization of the protocol, clinical samples (frozen PBMC) from patients with MS or type 1 diabetes and healthy control donors were evaluated with the BioLegend antibody. Results Clone 206D from BioLegend yielded optimal staining and the fix/perm reagents from both eBioscience and BioLegend were comparable. Data were also comparable between cells separated by Ficoll (fresh or frozen) and washed blood samples, allowing this protocol to be applicable to different types of samples. We validated this protocol using clinical samples and saw a significant increase in FoxP3 expression in the patients with type 1 diabetes but not in the MS. Conclusions The results from this study will allow the assessment of FoxP3 by flow cytometry on samples from clinical sites that are analyzed in real time on fresh blood or frozen PBMC. © 2008 Clinical Cytometry Society [source]


    Recombinant clotting factor VIII concentrates: Heterogeneity and high-purity evaluation

    ELECTROPHORESIS, Issue 16 2010
    Gian Maria D'Amici
    Abstract Factor VIII is an important glycoprotein involved in hemostasis. Insertion of expression vectors containing either the full-length cDNA sequence of human factor VIII (FLrFVIII) or B-domain deleted (BDDrFVIII) into mammalian cell lines results in the production of recombinant factor VIII (rFVIII) for therapeutic usage. Three commercially available rFVIII concentrates (Advate®, Helixate NexGen® and Refacto®), either FLrFVIII or BDDrFVIII, were investigated by 1- and 2-DE and MS. The objective of this study was to compare the heterogeneity and the high purity of both rFVIII preparations before and after thrombin digestion. In particular, the 2-D gel was optimized to better highlight the presence of contaminants and many unexpected proteins. Recombinant strategies consisting of insertion of expression vectors containing BDDrFVIII and FLrFVIII resulted in homogeneous and heterogeneous protein products, respectively, the latter consisting in a heterogeneous mixture of various B-domain-truncated forms of the molecule. Thrombin digestion of all the three rFVIII gave similar final products, plus one unexpected fragment of A2 domain missing 11 amino acids. Regarding the contaminants, Helixate NexGen® showed the presence of impurities, such as Hsp70,kDa, haptoglobin and proapolipoprotein; Refacto® showed glutathione S -transferase and ,-lactamase, whereas Advate® apparently did not contain any contaminants. The proteomic approach will contribute to improving the quality assurance and manufacturing processes of rFVIII concentrates. In this view, the 2-DE is mandatory for revealing the presence of contaminants. [source]


    CE coupled to MALDI with novel covalently coated capillaries

    ELECTROPHORESIS, Issue 4 2010
    Stefan Bachmann
    Abstract CE offers the advantage of flexibility and method development options. It excels in the area of separation of ions, chiral, polar and biological compounds (especially proteins and peptides). Masking the active sites on the inner surface of a bare fused silica capillary wall is often necessary for CE separations of basic compounds, proteins and peptides. The use of capillary surface coating is one of the approaches to prevent the adsorption phenomena and improve the repeatability of migration times and peak areas of these analytes. In this study, new capillary coatings consisting of (i) derivatized polystyrene nanoparticles and (ii) derivatized fullerenes were investigated for the analysis of peptides and protein digest by CE. The coated capillaries showed excellent run-to-run and batch-to-batch reproducibility (RSD of migration time ,0.5% for run-to-run and ,9.5% for batch-to-batch experiments). Furthermore, the capillaries offer high stability from pH 2.0 to 10.0. The actual potential of the coated capillaries was tested by combining CE with MALDI-MS for analysing complex samples, such as peptides, whereas the overall performance of the CE-MALDI-MS system was investigated by analysing a five-protein digest mixture. Subsequently, the peak list (peptide mass fingerprint) generated from the mass spectra of each fraction was entered into the Swiss-Prot database in order to search for matching tryptic fragments using the MASCOT software. The sequence coverage of analysed proteins was between 36 and 68%. The established technology benefits from the synergism of high separation efficiency and the structure selective identification via MS. [source]


    Improved workup for glycosaminoglycan disaccharide analysis using CE with LIF detection

    ELECTROPHORESIS, Issue 22 2008
    Alicia M. Hitchcock
    Abstract This work describes improved workup and instrumental conditions to enable robust, sensitive glycosaminoglycan (GAG) disaccharide analysis from complex biological samples. In the process of applying CE with LIF to GAG disaccharide analysis in biological samples, we have made improvements to existing methods. These include (i) optimization of reductive amination conditions, (ii) improvement in sensitivity through the use of a cellulose cleanup procedure for the derivatization, and (iii) optimization of separation conditions for robustness and reproducibility. The improved method enables analysis of disaccharide quantities as low as 1,pmol prior to derivatization. Biological GAG samples were exhaustively digested using lyase enzymes, the disaccharide products and standards were derivatized with the fluorophore 2-aminoacridone and subjected to reversed polarity CE-LIF detection. These conditions resolved all known chondroitin sulfate (CS) disaccharides or 11 of 12 standard heparin/heparan sulfate disaccharides, using 50,mM phosphate buffer, pH 3.5, and reversed polarity at 30,kV with 0.3,psi pressure. Relative standard deviation in migration times of CS ranged from 0.1 to 2.0% over 60 days, and the relative standard deviations of peak areas were less than 3.2%, suggesting that the method is reproducible and precise. The CS disaccharide compositions are similar to those obtained by our group using tandem MS. The reversed polarity CE-LIF disaccharide analysis protocol yields baseline resolution and quantification of heparin/heparan sulfate and CS/dermatan sulfate disaccharides from both standard preparations and biologically relevant proteoglycan samples. The improved CE-LIF method enables disaccharide quantification of biologically relevant proteoglycans from small samples of intact tissue. [source]


    Identification of rat urinary glycoproteome captured by three lectins using gel and LC-based proteomics

    ELECTROPHORESIS, Issue 21 2008
    Pyong-Gon Moon
    Abstract Many different types of urine proteome studies have been done, but urine glycoprotein studies are insufficient. Therefore, we studied the glycoproteins from rat urine, which could be used to identify biomarkers in an animal model. First, urinary proteins were prepared by using the dialysis and lyophilizing methods from rat urine. Glycoproteins enriched with lectin affinity purification, concanavalin A, jacalin and wheat germ agglutinin from the urinary proteins were separated by means of reverse-phase fast protein LC (FPLC) or 1-D PAGE. Each FPLC fraction and 1-D PAGE gel band were trypsin-digested and analyzed by means of nanoLC-MS/MS. LC-MS/MS analyses were carried out by using linear ion trap MS. A total of 318 rat urinary glycoproteins were identified from the FPLC fractions and gel bands; approximately 90% of identified proteins were confirmed as glycoproteins in Swiss-Prot. Many glycoproteins, known as biomarkers, including C-reactive protein, uromodulin, amyloid beta A4 protein, alpha-1-inhibitor 3, vitamin D-binding protein, kallikrein 3 and fetuin-A were identified in this study. By studying urinary glycoproteins collected from rat, these results may help to assist in identifying urinary biomarkers regarding various types of disease models. [source]


    Cyclodextrin-based nonaqueous electrokinetic chromatography with UV and mass spectrometric detection: Application to the impurity profiling of amiodarone,

    ELECTROPHORESIS, Issue 17 2008
    Roelof Mol
    Abstract The potential of nonaqueous electrokinetic chromatography (NAEKC) using cyclodextrins (CD) for the analysis of basic drugs and related compounds was evaluated. Both UV absorbance and mass spectrometric (MS) detection were employed. Addition of neutral CD to the NA background electrolyte did not significantly enhance the separation of a test mixture of basic drugs, and no change in selectivity was observed. In contrast, anionic single-isomer-sulfated CD strongly added to the selectivity of the NAEKC system inducing an improved resolution among the test compounds and increasing the migration time window. The applicability of the NAEKC system using anionic CD is demonstrated by the profiling of a sample of the drug amiodarone that had been stored for 1,year at room temperature. Amiodarone is poorly soluble in water. NAEKC-UV analysis indicated the presence of at least seven impurities in the amiodarone sample. In order to identify these compounds, the NAEKC system was coupled directly to electrospray ionization (ESI) ion-trap MS. The total of detected impurities increased to 12 due to the added sensitivity and selectivity of MS detection. Based on the acquired MS/MS data, three sample constituents could be identified as ,known' impurities (British Pharmacopoeia), whereas for three unknown impurities molecular structures could be proposed. Estimated limits of detection for amiodarone using the NAEKC method were 1,,g/mL with UV detection and 15,ng/mL with ESI-MS detection (full-scan). Based on relative responses, the impurity content of the stored drug substance was estimated to be 0.33 and 0.47% using NAEKC-UV and NAEKC-ESI-MS, respectively. [source]


    Electrokinetic supercharging for highly efficient peptide preconcentration in capillary zone electrophoresis

    ELECTROPHORESIS, Issue 7 2008
    Jean-Marc Busnel
    Abstract Electrokinetic supercharging has been integrated in CZE for the development of a highly sensitive methodology for protein tryptic digest analysis. A careful choice of the experimental conditions led to sensitivity enhancement factors between 1000 and 10,000 whilst maintaining a satisfactory resolution. Peptides in the low nanomolar concentration range have been detected despite the use of the poorly sensitive UV absorbance detection mode. The buffer system used in this study is fully suitable for coupling CE to MS. [source]


    Detection of carbonyl-modified proteins in interfibrillar rat mitochondria using N, -aminooxymethylcarbonylhydrazino- D -biotin as an aldehyde/keto-reactive probe in combination with Western blot analysis and tandem mass spectrometry

    ELECTROPHORESIS, Issue 6 2008
    Woon-Gye Chung
    Abstract There is now a large body of supporting data available that links oxidative modifications of proteins to a large number of diseases, degenerative disorders and aging. However, the detailed analysis of oxidative protein modifications remains challenging. Here, we report a new efficient method for identification of oxidatively modified proteins in complex biological samples which is based on the use of an aldehyde-reactive probe, N,-aminooxymethylcarbonylhydrazino- D -biotin (ARP), in combination with Western-type analyses and MS. The biotinylated hydroxylamine derivative forms a chemically stable oxime derivative with the aldehyde/keto group found in carbonyl-modified proteins. The biotin tag is detected by avidin affinity staining. ARP-positive proteins are subsequently subjected to in-gel trypsinization and MS/MS for protein identification. We demonstrate the usefulness of the method for the analysis of protein extracts obtained from interfibrillar heart mitochondria (IFM) from young and old rats. In this study, we identified as putative major protein targets of oxidative modifications the mitochondrial matrix protein, aconitase, the inner mitochondrial membrane protein, ADP/ATP translocase, and constituents of the electron transport chain complexes IV and V. An age-related increase of carbonyl levels was found for aconitase and ATP synthase. [source]


    A fully automated 2-D LC-MS method utilizing online continuous pH and RP gradients for global proteome analysis

    ELECTROPHORESIS, Issue 23 2007
    Hu Zhou
    Abstract The conventional 2-D LC-MS/MS setup for global proteome analysis was based on online and offline salt gradients (step and continuous) using strong-cation-exchange chromatography in conjunction with RP chromatography and MS. The use of the online system with step salt elution had the possibility of resulting in peptide overlapping across fractions. The offline mode had the option to operate with continuous salt gradient to decrease peak overlap, but exhibited decreased robustness, lower reproducibility, and sample loss during the process. Due to the extensive washing requirement between the chromatography steps, online continuous gradient was not an option for salt elution. In this report, a fully automated, online, and continuous gradient (pH continuous online gradient, pCOG) 2-D LC-MS/MS system is introduced that provided excellent separation and identification power. The pH gradient-based elution provided more basic peptides than that of salt-based elution. Fraction overlap was significantly minimized by combining pH and continuous gradient elutions. This latter approach also increased sequence coverage and the concomitant confidence level in protein identification. The salt and pH elution-based 2-D LC-MS/MS approaches were compared by analyzing the mouse liver proteome. [source]


    The role of electrophoresis in disease biomarker discovery

    ELECTROPHORESIS, Issue 12 2007
    Haleem J. Issaq Dr.
    Abstract There has been increased activity in the last few years in the search for disease markers using fractionation of complex biological fluids combined with MS. While electrophoretic and chromatographic separations have played a major role in this endeavor, this manuscript is limited to a review of electrophoretic methods that have been established for disease biomarker discovery. These methods include 2-DE, difference gel electrophoresis (DIGE), and CE. We define what constitutes a biomarker, identify the steps required for establishing a biomarker, and describe the parameters needed in the design of an ideal diagnostic test. The application, advantages, and limitations of CE, DIGE, and 2-DE in meeting the goal of discovering novel biomarkers is discussed in detail, along with a few selected examples that illustrate the search for biomarkers for cancer and neurological diseases. [source]


    Microfluidic technologies for MALDI-MS in proteomics

    ELECTROPHORESIS, Issue 18 2006
    Don L. DeVoe Professor
    Abstract The field of microfluidics continues to offer great promise as an enabling technology for advanced analytical tools. For biomolecular analysis, there is often a critical need to couple on-chip microfluidic sample manipulation with back-end MS. Though interfacing microfluidics to MS has been most often reported through the use of direct ESI-MS, there are compelling reasons for coupling microfluidics to MALDI-MS as an alternative to ESI-MS for both online and offline analysis. The intent of this review is to provide a summary of recent developments in the integration of microfluidic systems with MALDI-MS, with an emphasis on applications in proteomics. Key points are summarized, followed by a review of relevant technologies and a discussion of outlook for the field. [source]


    The metabolic syndrome in overweight epileptic patients treated with valproic acid

    EPILEPSIA, Issue 2 2010
    Alberto Verrotti
    Summary Purpose:, To evaluate the presence of metabolic syndrome (MS) in children and adolescents treated with valproate (VPA). Methods:, One hundred fourteen patients (54 male and 60 female) were studied. These patients were followed from the beginning of therapy for at least 24 months; at the end of follow-up, 46 patients (40.4%) had a considerable increase in body weight, whereas the other patients (59.6%) remained with the same weight. The MS was defined as having at least three of the following: abdominal obesity, dyslipidemia, glucose intolerance, and hypertension. Results:, Forty-six patients developed obesity; 20 (43.5%) of 46 patients developed MS. Abnormal glucose homeostasis was identified in 45% of patients. High total serum cholesterol concentrations were noted in 10 (50%), high serum triglyceride concentrations in 7 (35%), and low high-density lipoprotein (HDL) in 15 (75%) of the 20 subjects with MS. However, there were no significant differences in the features of MS between boys and girls with MS. Conclusions:, Patients who gain weight during VPA therapy can develop MS with a possible risk of cardiovascular disease. [source]


    Seizures in multiple sclerosis

    EPILEPSIA, Issue 6 2008
    Marcus Koch
    Summary Seizures have long been recognized to be part of the disease spectrum of multiple sclerosis (MS). While they occur in only a minority of patients with MS, epileptic seizures can have serious consequences. The treatment of MS can be epileptogenic, and antiepileptic treatment can conversely worsen the symptoms of MS. In this article we present an overview of the current literature on the epidemiology, clinical presentation, pathology, imaging, prognosis and treatment of epileptic seizures in MS. [source]


    A Combined Gas-Phase Electron Diffraction/Mass Spectrometric Study of the Sublimation Processes of TeBr4 and TeI4: The Molecular Structure of Tellurium Dibromide and Tellurium Diiodide

    EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 33 2008
    Sergey A. Shlykov
    Abstract The sublimation processes of TeBr4 at 471(5) K and TeI4 at 373(5) K were studied with a combined gas-phase electron diffraction and mass spectrometric technique (GED/MS). The mass spectra and the analysis of the GED intensities showed that a contribution of 40(3) mol-% TeBr2, 59(3) mol-% Br2, and 1 mol-% TeBr4 was formed in the vapor over TeBr4(s). Solid tellurium tetraiodide decomposes to form I2(g) and Te(s). A very small contribution of 3.3,±,2.1 mol-% of gaseous TeI2 was also determined by both GED and MS. The "metallic" Te accumulated in the solid phase vaporizes at above ca. 670 K as the predominately Te2 molcular species. Refinement of the GED intensities resulted in rg(Te,Br) = 2.480(5) Å and ,gBr,Te,Br = 99.0(6)° for TeBr2 and rg(Te,I) = 2.693(9) Å and ,g(I,Te,I) = 103.1(22)° for TeI2. The small contribution of TeBr4 observed in the mass spectra of the vapor over TeBr4 could not be observed in the GED data. Geometric parameters and vibrational frequencies for the tellurium dihalides TeX2 with X = F, Cl, Br, and I were calculated with B3LYP, MP2, CCSD, and CCSD(T) methods by using aug-cc-pVTZ basis sets and various core potentials for the tellurium atom. Bonding properties in tellurium dihalides are discussed on the basis of natural bond orbital analyses. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008) [source]


    Fatigue and processing speed are related in multiple sclerosis

    EUROPEAN JOURNAL OF NEUROLOGY, Issue 2 2010
    A. K. Andreasen
    Background:, Fatigue is common in multiple sclerosis (MS) and could be related to impaired processing speed caused by MS specific brain alterations. The objective of this study was to examine the relationship between processing speed and fatigue in patients with relapsing remitting MS. Methods:, Patients with EDSS score ,3.5 were grouped as fatigued [Fatigue Severity Scale (FSS) score ,5.0] or non-fatigued (FSS score ,4.0). Patients with FSS scores ,5 were categorized as primary or secondary fatigued according to various indices. A cognitive test battery obtained from Wechsler's Adult Intelligence Scale-III/Wechsler's Memory Scale-III was applied. Results:, Processing speed (Digit Symbol Coding) was lower amongst all MS patients being 9.4(2.9) in primary fatigued, 8.3(2.8) in secondary fatigued and 10.3(2.7) in non-fatigued versus 12.3(3.0) in healthy controls. In the combined group of primary and secondary fatigued MS patients, processing speed was slower than that in non-fatigued MS patients and inversely related to fatigue (r = ,0.35; P < 0.05). No such relationship could be established in non-fatigued MS patients or in healthy controls. Conclusion:, The degree of fatigue in MS is related to processing speed impairment and longitudinal studies should clarify their mutual dependency. [source]


    Elevated cerebrospinal fluid adiponectin and adipsin levels in patients with multiple sclerosis: a Finnish co-twin study

    EUROPEAN JOURNAL OF NEUROLOGY, Issue 2 2010
    A. Hietaharju
    Background and purpose:, The aim of this study was to investigate the levels of three adipocytokines: leptin, adiponectin and adipsin, in serum and cerebrospinal fluid (CSF) of twins discordant for multiple sclerosis (MS). Adipose tissue is an important component connecting immune system and several tissues and organs including CNS. Fat cells produce adipocytokines, which seem to have a role in various autoimmune disorders including MS. Methods:, Plasma samples were collected from twelve twins and CSF samples from four twins discordant for MS. The concentrations of interleukine (IL)-6, adiponectin, adipsin and leptin in plasma and CSF samples were determined by enzyme immuno assay. Results:, A significant difference was seen in the adipocytokine levels in CSF samples. Twins with MS had higher concentrations of adiponectin (P = 0.039) and adipsin (P = 0.039), than their asymptomatic co-twins. Conclusion:, As adiponectin and adipsin levels in CSF did not correlate with their levels in plasma, it seems that there could be a secondary intrathecal synthesis of these adipocytokines in MS. [source]


    MS and clinically isolated syndromes: Shared specificity but diverging clonal patterns of virus-specific IgG antibodies produced in vivo and by CSF B cells in vitro

    EUROPEAN JOURNAL OF NEUROLOGY, Issue 10 2009
    G. Skorstad
    Background:, Intrathecal synthesis of oligoclonal IgG antibodies against measles virus (MeV), varicella zoster virus (VZV) and herpes simplex virus type-1 (HSV-1) is a characteristic feature multiple sclerosis (MS). Methods:, We have used isoelectric focusing-immunoblot to define the clonal patterns of IgG and of IgG antibodies to MeV, VZV and HSV-1 in supernatants of in vitro cultures of peripheral blood lymphocytes (PBL) and cerebrospinal fluid (CSF) cells and in sera and CSF from three patients with MS and three patients with clinically isolated syndromes (CIS) suspective of demyelinating disease. Results:,In vitro synthesis of IgG by PBL was not detected in any patient. In contrast, in vitro synthesis by CSF cells of oligoclonal IgG and oligoclonal IgG antibodies to one or two of the three viruses tested was observed in all six patients. The clonal patterns of the in vitro synthesized IgG and virus specific IgG differed to varying extent from those synthesized intrathecally in vivo. However, in each patient, the in vitro and in vivo intrathecally produced antibodies displayed specificity for the same viruses. The addition of B cell activating factor (BAFF) had no effect on the amounts or clonal patterns of either total IgG or virus-specific IgG produced by CSF cells in vitro. Conclusion:, Virus specific B cells capable of spontaneous IgG synthesis are clonally expanded in the CSF of patients with MS. The B-cell repertoire in CSF samples is only partially representative of the intrathecal B-cell repertoire. [source]


    EFNS guideline on treatment of multiple sclerosis relapses: report of an EFNS task force on treatment of multiple sclerosis relapses

    EUROPEAN JOURNAL OF NEUROLOGY, Issue 12 2005
    F. Sellebjerg
    Relapses, exacerbations or attacks of multiple sclerosis are the dominating feature of relapsing-remitting multiple sclerosis (MS), but are also observed in patients with secondary progressive MS. High-dose methylprednisolone is the routine therapy for relapses at present, but other treatments are also in current use. The objective of the task force was to review the literature on treatment of MS relapses to provide evidence-based treatment recommendations. Review was carried out on the literature with classification of evidence according to the EFNS guidelines for scientific task forces. Short-term, high-dose methylprednisolone treatment should be considered for the treatment of relapses of MS (level A recommendation). The optimal glucocorticoid treatment regimen, in terms of clinical efficacy and adverse events, remains to be established. A more intense, interdisciplinary rehabilitation programme should be considered as this probably further improves recovery after treatment with methylprednisolone (level B recommendation). Plasma exchange is probably efficacious in a subgroup of patients with severe relapses not responding to methylprednisolone therapy, and should be considered in this patient subgroup (level B recommendation). There is a need for further randomized, controlled trials in order to establish the optimal treatment regimen for relapses of MS. [source]


    IL-10 promoter haplotype influence on interferon treatment response in multiple sclerosis

    EUROPEAN JOURNAL OF NEUROLOGY, Issue 3 2005
    S. Wergeland
    The level of interleukin-10 (IL-10) expression is related to polymorphisms -1082 (G/A), -819 (T/C) and -592 (A/C) in the promoter region of the IL-10 gene, which constitute three haplotypes, GCC, ATA, and ACC. The ATA (a non-GCC) haplotype, which is associated with low IL-10 expression, has been shown to improve interferon (IFN) treatment response in hepatitis C. We analysed the distribution of IL-10 promoter haplotype combinations to determine whether they could influence initial IFN treatment response in 63 patients with relapsing-remitting multiple sclerosis (MS). The patients were grouped into non-GCC or GCC haplotypes, and the clinical and magnetic resonance imaging (MRI) disease activity was compared in the two groups. During the first 6 months of treatment, MS patients with non-GCC haplotypes experienced fewer new MRI T1-contrast enhancing lesions [0.77 ± 0.36 (SEM)] than patients with the GCC haplotype (2.45 ± 0.57) (P = 0.05, Mann-Whitney U test). No differences were detected on clinical disease activity. The results suggest an influence of IL-10 promoter polymorphisms on IFN treatment response in MS. [source]


    PET visualization of microglia in multiple sclerosis patients using [11C]PK11195

    EUROPEAN JOURNAL OF NEUROLOGY, Issue 3 2003
    J. C. Debruyne
    Activated microglia are involved in the immune response of multiple sclerosis (MS). The peripheral benzodiazepine receptor (PBR) is expressed on microglia and up-regulated after neuronal injury. [11C]PK11195 is a positron emission tomography (PET) radioligand for the PBR. The objective of the present study was to investigate [11C]PK11195 imaging in MS patients and its additional value over magnetic resonance imaging (MRI) concerning the immuno-pathophysiological process. Seven healthy and 22 MS subjects were included. Semiquantitative [11C]PK11195 uptake values were assessed with normalization on cortical grey matter. Uptake in Gadolinium-lesions was significantly increased compared with normal white matter. Uptake in T2-lesions was generally decreased, suggesting a PBR down-regulation. However, uptake values increased whenever a clinical or MR-relapse was present, suggestive for a dynamic process with a transient PBR up-regulation. During disease progression, an increase of normal-appearing white matter (NAWM) uptake was found, propagating NAWM as the possible real burden of disease. In conclusion, [11C]PK11195 and PET are able to demonstrate inflammatory processes with microglial involvement in MS. [source]


    Increased numbers of mononuclear cells from blood and CSF expressing interferon-gamma mRNA in multiple sclerosis are from both the CD4+ and the CD8+ subsets

    EUROPEAN JOURNAL OF NEUROLOGY, Issue 1 2000
    E. Wallström
    Activated, cytokine-producing lymphocytes may regulate central nervous system (CNS) inflammation in multiple sclerosis (MS). We utilize a novel combination of in situ hybridization (ISH) and immunocytochemical staining of peripheral blood lymphocytes (PBLs) to identify spontaneously interferon-gamma (IFN,) mRNA expressing cells as CD4+ or CD8+. A major proportion of the IFN, mRNA expressing lymphocytes belonged to the CD4+ lineage, which concords with the cellular composition of MS brain lesions, findings in experimental models and the HLA class II haplotype association in MS. There were also significantly more CD8+ IFN, mRNA expressing lymphocytes in the MS patients compared with healthy controls, further suggesting the contribution of activated cells from this lineage in the inflammatory response in MS. Both CD4+ and CD8+ IFN, mRNA expressing cells were enriched in the cerebrospinal fluid (CSF) as compared with the peripheral blood of the MS patients. Combined with emerging genetic data on HLA class I influences, our data argues for a joint role of activated CD8+ and CD4+ cells in the pathogenesis of MS. [source]


    Study of the regulation of the endocannabinoid system in a virus model of multiple sclerosis reveals a therapeutic effect of palmitoylethanolamide

    EUROPEAN JOURNAL OF NEUROSCIENCE, Issue 4 2008
    Frida Lorķa
    Abstract Cannabinoids have recently been approved as a treatment for pain in multiple sclerosis (MS). Increasing evidence from animal studies suggests that this class of compounds could also prove efficient to fight neurodegeneration, demyelination, inflammation and autoimmune processes occurring in this pathology. However, the use of cannabinoids is limited by their psychoactive effects. In this context, potentiation of the endogenous cannabinoid signalling could represent a substitute to the use of exogenously administrated cannabinoid ligands. Here, we studied the expression of different elements of the endocannabinoid system in a chronic model of MS in mice. We first studied the expression of the two cannabinoid receptors, CB1 and CB2, as well as the putative intracellular cannabinoid receptor peroxisome proliferator-activated receptor-,. We observed an upregulation of CB2, correlated to the production of proinflammatory cytokines, at 60 days after the onset of the MS model. At this time, the levels of the endocannabinoid, 2-arachidonoylglycerol, and of the anti-inflammatory anandamide congener, palmithoylethanolamide, were enhanced, without changes in the levels of anandamide. These changes were not due to differences in the expression of the degradation enzymes, fatty acid amide hydrolase and monoacylglycerol lipase, or of biosynthetic enzymes, diacylglycerol lipase-, and N -acylphosphatidylethanolamine phospholipase-D at this time (60 days). Finally, the exogenous administration of palmitoylethanolamide resulted in a reduction of motor disability in the animals subjected to this model of MS, accompanied by an anti-inflammatory effect. This study overall highlights the potential therapeutic effects of endocannabinoids in MS. [source]


    ,- d -Mannopyranosyl-(1,2)-,- d -glucopyranosyl-(1,2)-glycerate in the thermophilic bacterium Petrotoga miotherma , structure, cellular content and function

    FEBS JOURNAL, Issue 12 2007
    Carla D. Jorge
    The intracellular accumulation of low molecular mass organic compounds in response to stressful conditions was investigated in the thermophilic bacterium Petrotoga miotherma, a member of the order Thermotogales. This led to the discovery of a new solute, whose structure was established as ,- d -mannopyranosyl-(1,2)-,- d -glucopyranosyl-(1,2)-glycerate (MGG) by MMR spectroscopy and MS. Under optimum growth conditions (3% NaCl; 55 °C), MGG was the major solute [up to 0.6 µmol·(mg protein),1]; ,-glutamate and proline were also present but in minor amounts [below 0.08 µmol·(mg protein),1]. The level of MGG increased notably with the salinity of the growth medium up to the optimum NaCl concentration. At higher NaCl concentrations, however, the level of MGG decreased, whereas the levels of proline and ,-glutamate increased about five-fold and 10-fold, respectively. MGG plays a role during low-level osmotic adaptation of Petrotoga miotherma, whereas ,-glutamate and, to a lesser extent, proline are used for osmoprotection under salt stress. MGG is not part of the cell strategy for coping with heat or oxidative stress. Nevertheless, MGG was an efficient protector of pig heart malate dehydrogenase against heat inactivation and freeze-drying, although mannosylglycerate was better. This is the first report on the occurrence of MGG in living systems. [source]


    Properties of pyranose dehydrogenase purified from the litter-degrading fungus Agaricus xanthoderma

    FEBS JOURNAL, Issue 3 2007
    Magdalena Kujawa
    We purified an extracellular pyranose dehydrogenase (PDH) from the basidiomycete fungus Agaricus xanthoderma using ammonium sulfate fractionation and ion-exchange and hydrophobic interaction chromatography. The native enzyme is a monomeric glycoprotein (5% carbohydrate) containing a covalently bound FAD as its prosthetic group. The PDH polypeptide consists of 575 amino acids and has a molecular mass of 65 400 Da as determined by MALDI MS. On the basis of the primary structure of the mature protein, PDH is a member of the glucose,methanol,choline oxidoreductase family. We constructed a homology model of PDH using the 3D structure of glucose oxidase from Aspergillus niger as a template. This model suggests a novel type of bi-covalent flavinylation in PDH, 9- S -cysteinyl, 8-,- N3-histidyl FAD. The enzyme exhibits a broad sugar substrate tolerance, oxidizing structurally different aldopyranoses including monosaccharides and oligosaccharides as well as glycosides. Its preferred electron donor substrates are d -glucose, d -galactose, l -arabinose, and d -xylose. As shown by in situ NMR analysis, d -glucose and d -galactose are both oxidized at positions C2 and C3, yielding the corresponding didehydroaldoses (diketoaldoses) as the final reaction products. PDH shows no detectable activity with oxygen, and its reactivity towards electron acceptors is rather limited, reducing various substituted benzoquinones and complexed metal ions. The azino-bis-(3-ethylbenzthiazolin-6-sulfonic acid) cation radical and the ferricenium ion are the best electron acceptors, as judged by the catalytic efficiencies (kcat/Km). The enzyme may play a role in lignocellulose degradation. [source]


    Identification of domains on the extrinsic 23 kDa protein possibly involved in electrostatic interaction with the extrinsic 33 kDa protein in spinach photosystem II

    FEBS JOURNAL, Issue 5 2004
    Akihiko Tohri
    To elucidate the domains on the extrinsic 23 kDa protein involved in electrostatic interaction with the extrinsic 33 kDa protein in spinach photosystem II, we modified amino or carboxyl groups of the 23 kDa protein to uncharged methyl ester groups with N -succinimidyl propionate or glycine methyl ester in the presence of a water-soluble carbodiimide, respectively. The N -succinimidyl propionate-modified 23 kDa protein did not bind to the 33 kDa protein associated with PSII membranes, whereas the glycine methyl ester-modified 23 kDa protein completely bound. This indicates that positive charges on the 23 kDa protein are important for electrostatic interaction with the 33 kDa protein associated with the PSII membranes. Mapping of the N -succinimidyl propionate-modified sites of the 23 kDa protein was performed using Staphylococcus V8 protease digestion of the modified protein followed by determination of the mass of the resultant peptide fragments with MALDI-TOF MS. The results showed that six domains (Lys11,Lys14, Lys27,Lys38, Lys40, Lys90,Lys96, Lys143,Lys152, Lys166,Lys174) were modified with N -succinimidyl propionate. In these domains, Lys11, Lys13, Lys33, Lys38, Lys143, Lys166, Lys170 and Lys174 were wholly conserved in the 23 kDa protein from 12 species of higher plants. These positively charged lysyl residues on the 23 kDa protein may be involved in electrostatic interactions with the negatively charged carboxyl groups on the 33 kDa protein, the latter has been suggested to be important for the 23 kDa binding [Bricker, T.M. & Frankel, L.K. (2003) Biochemistry42, 2056,2061]. [source]


    A combined stress response analysis of Spirulina platensis in terms of global differentially expressed proteins, and mRNA levels and stability of fatty acid biosynthesis genes

    FEMS MICROBIOLOGY LETTERS, Issue 2 2008
    Wattana Jeamton
    Abstract Changes in gene expression play a critical role in enhancing the ability of cyanobacteria to survive under cold conditions. In the present study, Spirulina platensis cultures were grown at the optimal growth temperature, in the light, before being transferred to dark conditions at 22 °C. Two dimensional-differential gel electrophoresis was then performed to separate differentially expressed proteins that were subsequently identified by MS. Among all differentiated proteins identified, a protein involved in fatty acid biosynthesis, (3R)-hydroxymyristoyl-[acyl-carrier-protein]-dehydratase encoded by fabZ, was the most up-regulated protein. However, the fatty-acid desaturation proteins were not significantly differentiated. This raised the question of how the unsaturated fatty acid, especially ,-linolenic acid, content in the cells in the cold,dark shift remained stable compared with that of the cold shift. Thus, a study at the transcriptional level of these desaturase genes, desC, desA and desD, and also of the fabZ gene was conducted. The results indicated that in the dark, where energy is limited, mRNA stability was enhanced by exposure to low temperatures. The data demonstrate that when the cells encounter cold stress with energy limitation, they can maintain their homeoviscous adaptation ability via mRNA stability. [source]


    Detection of a homotetrameric structure and protein,protein interactions of Paracoccidioides brasiliensis formamidase lead to new functional insights

    FEMS YEAST RESEARCH, Issue 1 2010
    Clayton Luiz Borges
    Abstract Paracoccidioides brasiliensis causes paracoccidioidomycosis, a systemic mycosis in Latin America. Formamidases hydrolyze formamide, putatively plays a role in fungal nitrogen metabolism. An abundant 45-kDa protein was identified as the P. brasiliensis formamidase. In this study, recombinant formamidase was overexpressed in bacteria and a polyclonal antibody to this protein was produced. We identified a 180-kDa protein species reactive to the antibody produced in mice against the P. brasiliensis recombinant purified formamidase of 45 kDa. The 180-kDa purified protein yielded a heat-denatured species of 45 kDa. Both protein species of 180 and 45 kDa were identified as formamidase by peptide mass fingerprinting using MS. The identical mass spectra generated by the 180 and the 45-kDa protein species indicated that the fungal formamidase is most likely homotetrameric in its native conformation. Furthermore, the purified formamidase migrated as a protein of 191 kDa in native polyacrylamide gel electrophoresis, thus revealing that the enzyme forms a homotetrameric structure in its native state. This enzyme is present in the fungus cytoplasm and the cell wall. Use of a yeast two-hybrid system revealed cell wall membrane proteins, in addition to cytosolic proteins interacting with formamidase. These data provide new insights into formamidase structure as well as potential roles for formamidase and its interaction partners in nitrogen metabolism. [source]


    Character impact odorants from wild mushroom (Lactarius hatsudake) used in Japanese traditional food

    FLAVOUR AND FRAGRANCE JOURNAL, Issue 4 2010
    Mitsuo Miyazawa
    Abstract The components of the volatile oil from wild mushroom (Lactarius hatsudake), used in Japanese traditional food, were analysed and quantified for the first time by capillary GC and GC,MS. Seventy-six components were separated from the oil and of these 71 components were identified. The main components of the oil were oxidized sesquiterpenes [cis -isolongifolanone (624.9,,g/100,g), , -cedrene epoxide (578.7,,g/100,g), humulene epoxide III (453.9,,g/100,g), clovane (425.4,,g/100,g)], aliphatic acids [linoleic acid (585.9,,g/100,g) and palmitoleic acid (333.3,,g/100,g)]. Odour evaluation of the volatile oil from L. hatsudake was also carried out using GC,MS/olfactometry (GC,MS/O) and aroma extract dilution analysis (AEDA), from which it was found that hexanal, 4-dehydroviridiflorol, myliol and phenylacetaldehyde seem to contribute to the green, spicy and sweet odour of L. hatsudake. Copyright © 2010 John Wiley & Sons, Ltd. [source]


    Histochemical localization of secretion and composition of the essential oil in Melittis melissophyllum L. subsp. melissophyllum from Central Italy

    FLAVOUR AND FRAGRANCE JOURNAL, Issue 2 2010
    Filippo Maggi
    Abstract The distribution and morphology of the secretory structures in Melittis melissophyllum L. subsp. melissophyllum (Lamiaceae) were studied for the first time by light and scanning electron microscopy. The indumentum of the vegetative and reproductive organs includes non-glandular hairs and peltate (type A) and capitate (types B and C) glandular trichomes. Histochemical techniques enabled specific location of the site of essential oil accumulation in the type A peltate hairs. In order to confirm the occurrence of the 1-octen-3-ol chemotype in central Italy, six populations growing in different places were analysed for the essential oil composition by GC,FID and GC,MS. In all populations, 1-octen-3-ol was detected as the major volatile component, representing 56.3,70.6% of the total oils. To date, these percentages are the highest detected in a plant essential oil. Copyright © 2009 John Wiley & Sons, Ltd. [source]