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  • 451.
    Wallménius, Katarina
    et al.
    Department of Medical Sciences, Section of Clinical Microbiology, Uppsala University.
    Barboutis, Christos
    Natural History Museum of Crete, University of Crete, Iraklion, Greece.
    Fransson, Thord
    Swedish Museum of Natural History, Department of.
    Jaenson, Thomas GT
    Medical Entomology Unit, Department of Organismal Biology, Uppsala University.
    Lindgren, Per-Eric
    Division of Medical Microbiology, Department of Clinical and Experimental Medicine, Linköping University.
    Nyström, Fredrik
    Division of Medical Microbiology, Department of Clinical and Experimental Medicine, Linköping University.
    Olsen, Björn
    Department of Medical Sciences, Section of Infectious Diseases, Uppsala University.
    Salanek, Erik
    Department of Medical Sciences, Section of Infectious Diseases, Uppsala University.
    Nilsson, Kenneth
    Department of Medical Sciences, Section of Clinical Microbiology, Uppsala University.
    Spotted fever Rickettsia species in Hyalomma and Ixodes ticks infesting migratory birds in the European Mediterranean area2014In: Parasites & Vectors, ISSN 1756-3305, E-ISSN 1756-3305, Vol. 7Article in journal (Refereed)
  • 452.
    Wallner, Fredrik K
    et al.
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Spjut, Sara
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Boström, Dan
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics. Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics, Energy Technology and Thermal Process Chemistry.
    Elofsson, Mikael
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Synthesis and evaluation of 2-(2-fluoro-4-hydroxymethyl-5-methoxy-phenoxy)acetic acid as a linker in solid-phase synthesis monitored by gel-phase 19F NMR spectroscopy2007In: Organic and biomolecular chemistry, ISSN 1477-0520, E-ISSN 1477-0539, Vol. 5, p. 2464-2471Article in journal (Refereed)
    Abstract [en]

    Gel-phase 19F NMR spectroscopy is a useful monitoring technique for solid-phase organic chemistry due to the high information content it delivers and swift acquisition times, using standard NMR spectrometers. This paper describes the synthesis of the novel linker 2-(2-fluoro-4-hydroxymethyl-5-methoxy-phenoxy)acetic acid in 29% yield over seven steps, using nucleophilic aromatic substitutions on 2,4,5-trifluorobenzonitrile as key steps. Following standard solid-phase synthesis a peptide could be cleaved from the linker using 20% TFA in CH2Cl2 in 30 minutes, in contrast to a previously described monoalkoxy linker that requires 90% TFA in water at elevated temperature. A resin-bound peptide could be successfully glycosylated using only two equivalents of a thioglycoside donor, activated with N-iodosuccinimide and trifluoromethanesulfonic acid, and subsequent cleavage and deprotection gave the target glycopeptide. Direct glycosylation of the linker itself followed by mild acidic cleavage gave a fully protected hemiacetal for further chemical manipulation.

  • 453. Wang, Z.
    et al.
    Fu, Y.
    Kang, Zhengzhong
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Theoretical Chemistry and Biology.
    Liu, X.
    Chen, N.
    Wang, Q.
    Tu, Yaoquan
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Theoretical Chemistry and Biology.
    Wang, L.
    Song, S.
    Ling, D.
    Song, H.
    Kong, X.
    Fan, C.
    Organelle-Specific Triggered Release of Immunostimulatory Oligonucleotides from Intrinsically Coordinated DNA-Metal-Organic Frameworks with Soluble Exoskeleton2017In: Journal of the American Chemical Society, ISSN 0002-7863, E-ISSN 1520-5126, Vol. 139, no 44, p. 15784-15791Article in journal (Refereed)
    Abstract [en]

    DNA has proven of high utility to modulate the surface functionality of metal-organic frameworks (MOFs) for various biomedical applications. Nevertheless, current methods for preparing DNA-MOF nanoparticles rely on either inefficient covalent conjugation or specific modification of oligonucleotides. In this work, we report that unmodified oligonucleotides can be loaded on MOFs with high density (∼2500 strands/particle) via intrinsic, multivalent coordination between DNA backbone phosphate and unsaturated zirconium sites on MOFs. More significantly, surface-bound DNA can be efficiently released in either bulk solution or specific organelles in live cells when free phosphate ions are present. As a proof-of-concept for using this novel type of DNA-MOFs in immunotherapy, we prepared a construct of immunostimulatory DNA-MOFs (isMOFs) by intrinsically coordinating cytosine-phosphate-guanosine (CpG) oligonucleotides on biocompatible zirconium MOF nanoparticles, which was further armed by a protection shell of calcium phosphate (CaP) exoskeleton. We demonstrated that isMOFs exhibited high cellular uptake, organelle specificity, and spatiotemporal control of Toll-like receptors (TLR)-triggered immune responses. When isMOF reached endolysosomes via microtubule-mediated trafficking, the CaP exoskeleton dissolved in the acidic environment and in situ generated free phosphate ions. As a result, CpG was released from isMOFs and stimulated potent immunostimulation in living macrophage cells. Compared with naked CpG-MOF, isMOFs exhibited 83-fold up-regulation in stimulated secretion of cytokines. We thus expect this isMOF design with soluble CaP exoskeleton and an embedded sequential "protect-release" program provides a highly generic approach for intracellular delivery of therapeutic nucleic acids.

  • 454.
    Webb, Matthew J
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Biochemistry and Organic Chemistry.
    Palmgren, Pål
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Surface and Interface Science.
    Pal, Prabir
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Surface and Interface Science.
    Karis, Olof
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Surface and Interface Science.
    Grennberg, Helena
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Biochemistry and Organic Chemistry.
    A simple method to produce almost perfect graphene on highly oriented pyrolytic graphite2011In: Carbon, ISSN 0008-6223, E-ISSN 1873-3891, Vol. 49, no 10, p. 3242-3249Article in journal (Refereed)
  • 455. Wergeland, Gro Janne H.
    et al.
    Fjermestad, Krister W.
    Marin, Carla E.
    Haugland, Bente Storm-Mowatt
    Silverman, Wendy K.
    Öst, Lars-Göran
    Stockholm University, Faculty of Social Sciences, Department of Psychology. Haukeland University Hospital, Norway; University of Bergen, Norway; Karolinska Institutet, Sweden.
    Havik, Odd E.
    Heiervang, Einar R.
    Predictors of dropout from community clinic child CBT for anxiety disorders2015In: Journal of Anxiety Disorders, ISSN 0887-6185, E-ISSN 1873-7897, Vol. 31, p. 1-10Article in journal (Refereed)
    Abstract [en]

    The aim was to investigate predictors of treatment dropout among 182 children (aged 8-15 years) participating in an effectiveness trial of manual-based 10-session individual and group cognitive behavior therapy (CBT) for anxiety disorders in community clinics. The dropout rate was 14.4%, with no significant difference between the two treatment conditions. We examined predictors for overall dropout (n=26), early (<= session 4, n = 15), and late dropout (>= session 5, n = 11). Overall dropout was predicted bylaw child and parent rated treatment credibility, and high parent self-rated internalizing symptoms. Low child rated treatment credibility predicted both early and late dropout. High parent self-rated internalizing symptoms predicted early dropout, whereas low parent rated treatment credibility predicted late dropout. These results highlight the importance of addressing treatment credibility, and to offer support for parents with internalizing symptoms, to help children and families remain in treatment.

  • 456.
    Westerberg, Per-Anton
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Renal Medicine.
    Kindmark, Andreas
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences.
    Tivesten, Åsa
    Wallenberg Laboratory for Cardiovascular Research, University of Göteborg, Göteborg, Sweden.
    Karlsson, Magnus
    Clinical and Molecular Osteoporosis Research Unit, Department of Clinical Sciences and Orthopedic Surgery, Lund University, Skåne University Hospital, Sweden..
    Mellström, Dan
    Center for Bone and Arthritis Research at the Sahlgrenska Academy, Institute of Medicine, the Sahlgrenska Academy at Göteborg University, Göteborg, Sweden..
    Ohlsson, Claes
    Center for Bone and Arthritis Research at the Sahlgrenska Academy, Institute of Medicine, the Sahlgrenska Academy at Göteborg University, Göteborg, Sweden..
    Larsson, Tobias
    Department of Clinical Science, Intervention and Technology, Karolinska Institute, Stockholm,.
    Linde, Torbjörn
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences.
    Ljunggren, Östen
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences.
    Klotho polymorphisms, FGF23 and mortality among elderly men (Swedish MrOs).Manuscript (preprint) (Other academic)
    Abstract [en]

     

    Westerberg, P-A and Kindmark, A contributed equally in preparation of the manuscript.

    Introduction. α-Klotho is the co receptor for Fibroblast growth factor(FGF)23and crucial for phosphate and vitamin D metabolism. Variants in the KLOTHO (KL) gene are associated with longevity and cardiovascular morbidities. Primary aim of this study is to examine if variations in  KL affect mortality risk in a cohort of elderly men. Secondary aims are to examine associations with serum levels of FGF23, phosphate and renal function.

    Methods and results. 27 single nucleotide polymorphisms (SNP) in KLOTHO were genotyped using single base primer extension mass array technique on samples from 2924 men, aged 69 to 81 years, included in Swedish MrOs. After in average 6.1 years of follow up 584 had died, 214 of cardiovascular cause.  After quality analyses and tagging of haplotypes 11 SNPs were analyzed for variation in  mortality risk, serum levels of FGF23, phosphate, calcium and renal function. There were no associations with mortality of all cause. One SNP, (rs398655), in proximity to the promoter, demonstrated an increased Hazard ratio (95% Confidence interval(CI)) of 53% (95% CI, 8-118%) for death due to CVD in heterozygotes compared to homozygotes. Analysis using a dominant model showed an association between SNPs in the 5’ end of the gene and eGFR, phosphate level and logFGF23 (P=0.01).

    Conclusion. KL polymorphisms are associated with variation in FGF23 and phosphate.

  • 457.
    Westerlund, Jessica
    Örebro University, School of Medical Sciences.
    Occupational exposure to trichloramine and trihalomethanes: adverse respiratory and ocular effects among Swedish indoor swimming pool workers2016Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Occupational exposure in swimming pool facilities related to disinfection by-products (DBPs) has been an issue for the last 15 years. Trichloramine (NCl3) and trihalomethanes (THMs) are DBPs formed in swimming pool water following a reaction between organic matter containing nitrogen or organic or inorganic matter, and chlorine. Due to its volatility, trichloramine can easily evaporate into the air and cause nausea and irritation of the eyes and upper airways. Symptoms are likely to be particularly pronounced in those suffering from asthma. Chloroform is the dominant THM in swimming pool atmospheres and is classified by the International Agency for Research on Cancer (IARC) as being possibly carcinogenic to humans. There are no adverse health effects reported among swimming pool employees due to occupational exposure levels of THMs found in the air at swimming pools.

    There is no OEL for trichloramine adapted in Sweden, but some reference values and recommendations based on stationary measurements at the pool side are available. In 2006, the World Health Organisation (WHO) recommended a reference value for trichloramine of 500 μg/m3. The Swedish OEL for chloroform is 10 000 μg/m3.

    This thesis describes research into the occupational exposure to airborne trichloramine and THMs in eight Swedish indoor swimming pool facilities and the investigation into the prevalence of adverse health effects, manifesting primarily as ocular and respiratory symptoms.

    Concentrations of trichloramine and chloroform in Swedish indoor swimming pool facilities were found to be in the same range or lower compared to previous studies in other countries. The trichloramine concentrations varied between <1 and 240 μg/m3 for the personal sampling and between <1 and 640 μg/m3 for the stationary sampling. Personal trichloramine levels in the high-exposure group were more than 60% higher compared to the corresponding stationary measurements. The exposed group had a higher frequency of self-reported ocular and nasal symptoms compared to the controls. A significant difference in the concentration of exhaled FENO over a work shift with an increase in the exposed group, indicated acute airway inflammation due to respiratory irritant agent exposure. Although a dose-response effect could not be established, the results indicate an elevated risk of occupational health problems in indoor swimming pools and calls for an OEL to be established, based on personal sampling.

  • 458.
    Westerlund, Kristina
    et al.
    KTH, School of Biotechnology (BIO), Protein Technology.
    Honarvar, H.
    Tolmachev, V.
    Eriksson Karlström, Amelie
    KTH, School of Biotechnology (BIO), Protein Technology.
    Design, Preparation, and Characterization of PNA-Based Hybridization Probes for Affibody-Molecule-Mediated Pretargeting2015In: Bioconjugate chemistry, ISSN 1043-1802, E-ISSN 1520-4812, Vol. 26, no 8, p. 1724-1736Article in journal (Refereed)
    Abstract [en]

    In radioimmunotherapy, the contrast between tumor and normal tissue can be improved by using a pretargeting strategy with a primary targeting agent, which is conjugated to a recognition tag, and a secondary radiolabeled molecule binding specifically to the recognition tag. The secondary molecule is injected after the targeting agent has accumulated in the tumor and is designed to have a favorable biodistribution profile, with fast clearance from blood and low uptake in normal tissues. In this study, we have designed and evaluated two complementary peptide nucleic acid (PNA)-based probes for specific and high-affinity association in vivo. An anti-HER2 Affibody-PNA chimera, Z<inf>HER2:342</inf>-SR-HP1, was produced by a semisynthetic approach using sortase A catalyzed ligation of a recombinantly produced Affibody molecule to a PNA-based HP1-probe assembled using solid-phase chemistry. A complementary HP2 probe carrying a DOTA chelator and a tyrosine for dual radiolabeling was prepared by solid-phase synthesis. Circular dichroism (CD) spectroscopy and UV thermal melts showed that the probes can hybridize to form a structured duplex with a very high melting temperature (T<inf>m</inf>), both in HP1:HP2 and in Z<inf>HER2:342</inf>-SR-HP1:HP2 (T<inf>m</inf> = 86-88 °C), and the high binding affinity between Z<inf>HER2:342</inf>-SR-HP1 and HP2 was confirmed in a surface plasmon resonance (SPR)-based binding study. Following a moderately fast association (1.7 × 105 M-1 s-1), the dissociation of the probes was extremely slow and <5% dissociation was observed after 17 h. The equilibrium dissociation constant (K<inf>D</inf>) for Z<inf>HER2:342</inf>-SR-HP1:HP2 binding to HER2 was estimated by SPR to be 212 pM, suggesting that the conjugation to PNA does not impair Affibody binding to HER2. The biodistribution profiles of 111In- and 125I-labeled HP2 were measured in NMRI mice, showing very fast blood clearance rates and low accumulation of radioactivity in kidneys and other organs. The measured radioactivity in blood was 0.63 ± 0.15 and 0.41 ± 0.15%ID/g for 125I- and 111In-HP2, respectively, at 1 h p.i., and at 4 h p.i., the kidney accumulation of radioactivity was 0.17 ± 0.04%ID/g for 125I-HP2 and 3.83 ± 0.39%ID/g for 111In-HP2. Taken together, the results suggest that a PNA-based system has suitable biophysical and in vivo properties and is a promising approach for pretargeting of Affibody molecules.

  • 459.
    Wiberg, Anna
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Immunology, Genetics and Pathology.
    Granstam, Anna
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Immunology, Genetics and Pathology.
    Ingvast, Sofie
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Immunology, Genetics and Pathology.
    Harkonen, T.
    Univ Helsinki, Childrens Hosp, Helsinki, Finland.;Univ Helsinki, Cent Hosp, Helsinki, Finland.;Univ Helsinki, Diabet & Obes Res Program, Helsinki, Finland..
    Knip, M.
    Univ Helsinki, Childrens Hosp, Helsinki, Finland.;Univ Helsinki, Cent Hosp, Helsinki, Finland.;Univ Helsinki, Diabet & Obes Res Program, Helsinki, Finland.;Folkkhalsan Res Ctr, Helsinki, Finland.;Tampere Univ Hosp, Dept Pediat, Tampere, Finland..
    Korsgren, Olle
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Immunology, Genetics and Pathology.
    Skog, Oskar
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Immunology, Genetics and Pathology.
    Characterization of human organ donors testing positive for type 1 diabetes-associated autoantibodies2015In: Clinical and Experimental Immunology, ISSN 0009-9104, E-ISSN 1365-2249, Vol. 182, no 3, p. 278-288Article in journal (Refereed)
    Abstract [en]

    In this study we aim to describe the characteristics of non-diabetic organ donors with circulating diabetes-associated autoantibodies collected within the Nordic Network for Islet Transplantation. One thousand and thirty organ donors have been screened in Uppsala for antibodies against glutamic acid decarboxylase (GADA) and islet antigen-2 (IA-2A). The 32 non-diabetic donors that tested positive for GADA (33% of all non-diabetic donors) were studied in more detail, together with 32 matched controls. Mean age among the autoantibody-positive donors was 526 (range 21-74), family history of type 1 diabetes (T1D) was unknown, and no donor was genetically predisposed for T1D regarding the human leucocyte antigen (HLA) locus. Subjects were analysed for islet cell antibodies (ICA), insulin autoantibodies (IAA) and zinc transporter 8 antibodies (ZnT8A), and pancreas morphology and clinical data were examined. Eight non-diabetic donors tested positive for two antibodies and one donor tested positive for four antibodies. No insulitis or other signs of a diabetic process were found in any of the donors. While inflammatory cells were present in all donors, subjects with high GADA titres had significantly higher CD45 cell numbers in exocrine tissue than controls. The extent of fibrosis was more pronounced in autoantibody-positive donors, even in subjects with lower GADA titres. Notably, it is possible that events not related directly to T1D (e.g. subclinical pancreatitis) may induce autoantibodies in some cases.

  • 460.
    Wiberg, Jörgen
    Umeå University, Faculty of Medicine, Department of Medical Biochemistry and Biophysics.
    Mechanisms controlling DNA damage survival and mutation rates in budding yeast2012Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    All living organisms are made of cells, within which genetic information is stored on long strands of deoxyribonucleic acid (DNA). The DNA encodes thousands of different genes and provides the blueprint for all of the structures and activities occurring within the cell. The building blocks of DNA are the four deoxyribonucleotides, dATP, dGTP, dTTP, and dCTP, which are collectively referred to as dNTPs.

    The key enzyme in the production of dNTPs is ribonucleotide reductase (RNR). In the budding yeast Saccharomyces cerevisiae, the concentrations of the individual dNTPs are not equal and it is primarily RNR that maintains this balance. Maintenance of the dNTP pool balance is critical for accurate DNA replication and DNA repair since elevated and/or imbalanced dNTP concentrations increase the mutation rate and can ultimately lead to genomic instability and cancer. In response to DNA damage, the overall dNTP concentration in S. cerevisiae increases. Cell survival rates increase as a result of the elevated concentration of dNTPs, but the cells also suffer from a concomitant increase in mutation rates. When the replication machinery encounters DNA damage that it cannot bypass, the replication fork stalls and recruits specialized translesion synthesis (TLS) polymerases that bypass the damage so that replication can continue. We hypothesized that elevated dNTP levels in response to DNA damage may allow the TLS polymerases to more efficiently bypass DNA damage. To explore this possibility, we deleted all known TLS polymerases in a yeast strain in which we could artificially increase the dNTP concentrations. Surprisingly, even though all TLS polymerases had been deleted, elevated dNTP concentrations led to increased cell survival after DNA damage. These results suggest that replicative DNA polymerases may be involved in the bypass of certain DNA lesions under conditions of elevated dNTPs. We confirmed this hypothesis in vitro by demonstrating that high dNTP concentrations result in an increased efficiency in the bypass of certain DNA lesions by DNA polymerase epsilon, a replicative DNA polymerase not normally associated with TLS activity.

    We asked ourselves if it would be possible to create yeast strains with imbalanced dNTP concentrations in vivo, and, if so, would these imbalances be recognized by the checkpoint control mechanisms in the cell. To address these questions, we focused on the highly conserved loop2 of the allosteric specificity site of yeast Rnr1p. We introduced several mutations into RNR1-loop2 that resulted in changes in the amino acid sequence of the protein.

    Each of the rnr1-loop2 mutation strains obtained had different levels of individual dNTPs relative to the others. Interestingly, all of the imbalanced dNTP concentrations led to increased mutation rates, but these mutagenic imbalances did not activate the S-phase checkpoint unless one or several dNTPs were present at concentrations that were too low to sustain DNA replication. We were able to use these mutant yeast strains to successfully correlate amino acid substitutions within loop2 of Rnr1p to specific ratios of dNTP concentrations in the cells. We also demonstrated that specific imbalances between the individual dNTP levels result in unique mutation spectra. These mutation spectra suggest that the mutagenesis that results from imbalanced dNTP pools is due to a decrease in fidelity of the replicative DNA polymerases at specific DNA sequences where they are more likely to make a mistake. The mutant rnr1-loop2 strains that we have created with defined dNTP pool imbalances will be of great value for in vivo studies of polymerase fidelity, translesion synthesis by specialized DNA polymerases, and lesion recognition by the DNA repair machinery.

  • 461.
    Widenkvist, Erika
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Materials Chemistry.
    Quinlan, Ronald A.
    Dept of Applied Science.
    Holloway, Brian C.
    Luna Innovations Nano Works Division.
    Grennberg, Helena
    Dept of biochemistry and organic chemistry.
    Jansson, Ulf
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Materials Chemistry.
    Synthesis of Nanostructed Tungsten Oxide Thin Films2008In: Crystal Growth & Design, ISSN 1528-7483, E-ISSN 1528-7505, Vol. 8, no 10, p. 3750-3753Article in journal (Refereed)
    Abstract [en]

    A facile and inexpensive method to produce thin films of nanostructured tungsten oxide is described. A nanocrystalline tungstite (WO3·H2O) film is spontaneously formed when a tungsten substrate is immersed in nitric acid at elevated temperatures. The resulting thin film is composed of plate-like tungstite crystals with edges preferentially directed out from the substrate surface. The tungstite can easily be transformed into WO3 by annealing. Patterned WO3·H2O/W structures can be obtained by a combination of lithographic techniques and etching. In this study, the effect of exposure time, acid concentration, and temperature on the microstructure of the films has been investigated. The potential of this inexpensive synthesis method to produce large-area coatings of nanostructured tungsten oxide as well as patterned films makes it interesting for several different applications, such as batteries, gas sensors, and photocatalysts.

  • 462.
    Xin, D. L.
    et al.
    Department of Surgery, University of Pennsylvania, USA.
    Hadrevi, Jenny
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Occupational and Environmental Medicine.
    Elliott, M. E.
    Department of Neurosurgery, Thomas Jefferson University, USA.
    Amin, M
    Department of Anatomy and Cell Biology, Temple University School of Medicine, Philadephia, USA.
    Harris, M. Y.
    Department of Anatomy and Cell Biology, Temple University School of Medicine, Philadelphia, USA.
    Barr-Gillespie, A
    College of Health Professions, Pacific University, USA.
    Barbe, M. F.
    Department of Anatomy and Cell Biology, Temple University School of Medicine, Philadelphia, USA.
    Effectiveness of conservative interventions for sickness and pain behaviors induced by a high repetition high force upper extremity task2017In: BMC neuroscience (Online), ISSN 1471-2202, E-ISSN 1471-2202, Vol. 18, article id 36Article in journal (Refereed)
    Abstract [en]

    Background: Systemic inflammation is known to induce sickness behaviors, including decreased social interaction and pain. We have reported increased serum inflammatory cytokines in a rat model of repetitive strain injury (rats perform an upper extremity reaching task for prolonged periods). Here, we sought to determine if sickness behaviors are induced in this model and the effectiveness of conservative treatments.

    Methods: Experimental rats underwent initial training to learn a high force reaching task (10 min/day, 5 days/week for 6 weeks), with or without ibuprofen treatment (TRHF vs. TRHF + IBU rats). Subsets of trained animals went on to perform a high repetition high force (HRHF) task for 6 or 12 weeks (2 h/day, 3 days/week) without treatment, or received two secondary interventions: ibuprofen (HRHF + IBU) or a move to a lower demand low repetition low force task (HRHF-to-LRLF), beginning in task week 5. Mixed-effects models with repeated measures assays were used to assay duration of social interaction, aggression, forepaw withdrawal thresholds and reach performance abilities. One-way and two-way ANOVAs were used to assay tissue responses. Corrections for multiple comparisons were made.

    Results: TRHF + IBU rats did not develop behavioral declines or systemic increases in IL-1beta and IL-6, observed in untreated TRHF rats. Untreated HRHF rats showed social interaction declines, difficulties performing the operant task and forepaw mechanical allodynia. Untreated HRHF rats also had increased serum levels of several inflammatory cytokines and chemokines, neuroinflammatory responses (e.g., increased TNFalpha) in the brain, median nerve and spinal cord, and Substance P and neurokinin 1 immunoexpression in the spinal cord. HRHF + IBU and HRHF-to-LRLF rats showed improved social interaction and reduced inflammatory serum, nerve and brain changes. However, neither secondary treatment rescued HRHF-task induced forepaw allodynia, or completely attenuated task performance declines or spinal cord responses.

    Conclusions: These results suggest that inflammatory mechanisms induced by prolonged performance of high physical demand tasks mediate the development of social interaction declines and aggression. However, persistent spinal cord sensitization was associated with persistent behavioral indices of discomfort, despite use of conservative secondary interventions indicating the need for prevention or more effective interventions.

  • 463. Xu, Jing
    et al.
    Marsac, Remi
    Costa, Dominique
    Cheng, Wei
    Wu, Feng
    Boily, Jean-Francois
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Hanna, Khalil
    Co-Binding of Pharmaceutical Compounds at Mineral Surfaces: Molecular Investigations of Dimer Formation at Goethite/Water Interfaces2017In: Environmental Science and Technology, ISSN 0013-936X, E-ISSN 1520-5851, Vol. 51, no 15, p. 8343-8349Article in journal (Refereed)
    Abstract [en]

    The emergence of antibiotic and anti-inflammatory agents in aquatic and terrestrial systems is becoming a serious threat to human and animal health worldwide. Because pharmaceutical compounds rarely exist individually in nature, interactions between various compounds can have unforeseen effects on their binding to mineral surfaces. This work demonstrates this important possibility for the case of two typical antibiotic and anti-inflammatory agents (nalidixic acid (NA) and niflumic acid (NFA)) bound at goethite (alpha FeOOH) used as a model mineral surface. Our multidisciplinary study, which makes use of batch sorption experiments, vibration spectroscopy and periodic density functional theory calculations, reveals enhanced binding of the otherwise weakly bound NFA caused by unforeseen intermolecular interactions with mineral-bound NA. This enhancement is ascribed to the formation of a NFA NA dimer whose energetically favored formation (-0.5 eV compared to free molecules) is predominantly driven by van der Waals interactions. A parallel set of efforts also showed that no. cobinding occurred with sulfamethoxazole (SMX) because of the lack of molecular interactions with coexisting contaminants. As such, this article raises the importance of recognizing drug cobinding, and lack of cobinding, for predicting and developing policies on the fate of complex mixtures of antibiotics and anti-inflammatory agents in nature.

  • 464.
    Yang, Lingling
    et al.
    State Key Laboratory Cultivation Base, Shandong Provincial Key Laboratory of Ophthalmology, Shandong Eye Institute, Shandong Academy of Medical Sciences, Qingdao, China.
    Di, Guohu
    State Key Laboratory Cultivation Base, Shandong Provincial Key Laboratory of Ophthalmology, Shandong Eye Institute, Shandong Academy of Medical Sciences, Qingdao, China.
    Qi, Xia
    State Key Laboratory Cultivation Base, Shandong Provincial Key Laboratory of Ophthalmology, Shandong Eye Institute, Shandong Academy of Medical Sciences, Qingdao, China.
    Qu, Mingli
    State Key Laboratory Cultivation Base, Shandong Provincial Key Laboratory of Ophthalmology, Shandong Eye Institute, Shandong Academy of Medical Sciences, Qingdao, China.
    Wang, Yao
    State Key Laboratory Cultivation Base, Shandong Provincial Key Laboratory of Ophthalmology, Shandong Eye Institute, Shandong Academy of Medical Sciences, Qingdao, China.
    Duan, Haoyun
    State Key Laboratory Cultivation Base, Shandong Provincial Key Laboratory of Ophthalmology, Shandong Eye Institute, Shandong Academy of Medical Sciences, Qingdao, China.
    Danielson, Patrik
    Umeå University, Faculty of Medicine, Department of Integrative Medical Biology (IMB), Anatomy.
    Xie, Lixin
    State Key Laboratory Cultivation Base, Shandong Provincial Key Laboratory of Ophthalmology, Shandong Eye Institute, Shandong Academy of Medical Sciences, Qingdao, China.
    Zhou, Qingjun
    State Key Laboratory Cultivation Base, Shandong Provincial Key Laboratory of Ophthalmology, Shandong Eye Institute, Shandong Academy of Medical Sciences, Qingdao, China.
    Substance P promotes diabetic corneal epithelial wound healing through molecular mechanisms mediated via the neurokinin-1 receptor.2014In: Diabetes, ISSN 0012-1797, E-ISSN 1939-327X, Vol. 63, no 12, p. 4262-4274Article in journal (Refereed)
    Abstract [en]

    Substance P (SP) is a neuropeptide, predominantly released from sensory nerve fibers, with a potentially protective role in diabetic corneal epithelial wound healing. However, the molecular mechanism remains unclear. We investigated the protective mechanism of SP against hyperglycemia-induced corneal epithelial wound healing defects, using type 1 diabetic mice and high glucose-treated corneal epithelial cells. Hyperglycemia induced delayed corneal epithelial wound healing, accompanied with attenuated corneal sensation, mitochondrial dysfunction, and impairments of Akt-, EGFR-, and Sirt1-activation, as well as decreased reactive oxygen species (ROS) scavenging capacity. However, SP application promoted the epithelial wound healing, the recovery of corneal sensation, the improvement of mitochondrial function, and the reactivation of Akt, EGFR and Sirt1, as well as increased ROS scavenging capacity, in both diabetic mouse corneal epithelium and high glucose-treated corneal epithelial cells. The promotion of SP on diabetic corneal epithelial healing was completely abolished by a NK-1 receptor antagonist. Moreover, the subconjunctival injection of NK-1 receptor antagonist also caused diabetic corneal pathological changes in normal mice. In conclusion, the results suggest that SP-NK-1 receptor signaling plays a critical role in the maintenance of corneal epithelium homeostasis, and that SP signaling through the NK-1 recssssseptor contributes to the promotion of diabetic corneal epithelial wound healing by rescued activation of Akt, EGFR, and Sirt1, improvement of mitochondrial function, and increased ROS scavenging capacity.

  • 465.
    Yang, Wenzhi
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Biochemistry and Organic Chemistry.
    Widenkvist, Erika
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Materials Chemistry, Inorganic Chemistry.
    Jansson, Ulf
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Materials Chemistry, Inorganic Chemistry.
    Grennberg, Helena
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Biochemistry and Organic Chemistry, Organic Chemistry.
    Stirring-induced aggregation of graphene in suspension2011In: New Journal of Chemistry, ISSN 1144-0546, E-ISSN 1369-9261, Vol. 35, no 4, p. 780-783Article in journal (Refereed)
    Abstract [en]

    Graphene in suspension undergoes stirring-induced aggregation that leads to reversible agglomeration and folding/scrolling, all of which affects the Raman spectra; the findings are of importance in all solution-based protocols for graphene preparation and processing.

  • 466. Yousefzadeh, Matthew J
    et al.
    Wyatt, David W
    Takata, Kei-Ichi
    Mu, Yunxiang
    Hensley, Sean C
    Tomida, Junya
    Bylund, Göran O
    Umeå University, Faculty of Medicine, Department of Medical Biochemistry and Biophysics.
    Doublié, Sylvie
    Johansson, Erik
    Umeå University, Faculty of Medicine, Department of Medical Biochemistry and Biophysics.
    Ramsden, Dale A
    McBride, Kevin M
    Wood, Richard D
    Mechanism of suppression of chromosomal instability by DNA polymerase POLQ2014In: PLOS Genetics, ISSN 1553-7390, E-ISSN 1553-7404, Vol. 10, no 10, p. e1004654-Article in journal (Refereed)
    Abstract [en]

    Although a defect in the DNA polymerase POLQ leads to ionizing radiation sensitivity in mammalian cells, the relevant enzymatic pathway has not been identified. Here we define the specific mechanism by which POLQ restricts harmful DNA instability. Our experiments show that Polq-null murine cells are selectively hypersensitive to DNA strand breaking agents, and that damage resistance requires the DNA polymerase activity of POLQ. Using a DNA break end joining assay in cells, we monitored repair of DNA ends with long 3' single-stranded overhangs. End joining events retaining much of the overhang were dependent on POLQ, and independent of Ku70. To analyze the repair function in more detail, we examined immunoglobulin class switch joining between DNA segments in antibody genes. POLQ participates in end joining of a DNA break during immunoglobulin class-switching, producing insertions of base pairs at the joins with homology to IgH switch-region sequences. Biochemical experiments with purified human POLQ protein revealed the mechanism generating the insertions during DNA end joining, relying on the unique ability of POLQ to extend DNA from minimally paired primers. DNA breaks at the IgH locus can sometimes join with breaks in Myc, creating a chromosome translocation. We found a marked increase in Myc/IgH translocations in Polq-defective mice, showing that POLQ suppresses genomic instability and genome rearrangements originating at DNA double-strand breaks. This work clearly defines a role and mechanism for mammalian POLQ in an alternative end joining pathway that suppresses the formation of chromosomal translocations. Our findings depart from the prevailing view that alternative end joining processes are generically translocation-prone.

  • 467.
    Yu, Ji-Guo
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Bonnerud, Patrik
    Department of Health Sciences, Luleå University of Technology, Luleå.
    Eriksson, Anders
    Department of Health Sciences, Luleå University of Technology, Luleå.
    Stål, Per S.
    Umeå University, Faculty of Medicine, Department of Integrative Medical Biology (IMB), Anatomy.
    Tegner, Yelverton
    Department of Health Sciences, Luleå University of Technology, Luleå.
    Malm, Christer
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Effects of long term supplementation of anabolic androgen steroids on human skeletal muscle2014In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 9, no 9, article id e105330Article in journal (Refereed)
    Abstract [en]

    The effects of long-term (over several years) anabolic androgen steroids (AAS) administration on human skeletal muscle are still unclear. In this study, seventeen strength training athletes were recruited and individually interviewed regarding self-administration of banned substances. Ten subjects admitted having taken AAS or AAS derivatives for the past 5 to 15 years (Doped) and the dosage and type of banned substances were recorded. The remaining seven subjects testified to having never used any banned substances (Clean). For all subjects, maximal muscle strength and body composition were tested, and biopsies from the vastus lateralis muscle were obtained. Using histochemistry and immunohistochemistry (IHC), muscle biopsies were evaluated for morphology including fiber type composition, fiber size, capillary variables and myonuclei. Compared with the Clean athletes, the Doped athletes had significantly higher lean leg mass, capillary per fibre and myonuclei per fiber. In contrast, the Doped athletes had significantly lower absolute value in maximal squat force and relative values in maximal squat force (relative to lean body mass, to lean leg mass and to muscle fiber area). Using multivariate statistics, an orthogonal projection of latent structure discriminant analysis (OPLS-DA) model was established, in which the maximal squat force relative to muscle mass and the maximal squat force relative to fiber area, together with capillary density and nuclei density were the most important variables for separating Doped from the Clean athletes (regression  =  0.93 and prediction  =  0.92, p<0.0001). In Doped athletes, AAS dose-dependent increases were observed in lean body mass, muscle fiber area, capillary density and myonuclei density. In conclusion, long term AAS supplementation led to increases in lean leg mass, muscle fiber size and a parallel improvement in muscle strength, and all were dose-dependent. Administration of AAS may induce sustained morphological changes in human skeletal muscle, leading to physical performance enhancement.

  • 468.
    Zakrisson Mortensson, Elin
    et al.
    Jönköping University, School of Health and Welfare, HHJ, Dep. of Natural Science and Biomedicine.
    Öhlen, Malin
    Jönköping University, School of Health and Welfare, HHJ, Dep. of Natural Science and Biomedicine.
    Samband mellan tandvårdsrädsla och temperament- vilken betydelse har kön och utländsk bakgrund?: En tvärsnittsstudie på ungdomar i nionde klass i Jönköpings kommun2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Summary

     

    Associations between dental fear and temperament - does sex or foreign origin have an impact? A cross-sectional study of youths in the ninth grade in Jönköping.

     

    Background: Dental fear is a common problem in dental care which can contribute to a poor oral health. Previous research shows certain correlations between dental fear and temperaments but varies. Objective: The aim of this study was to investigate the association between dental fear and temperament of youths in ninth grade. Method: The study is a cross-sectional study based on a stratified sample of youths in ninth grade. Two validated questionnaires containing self-reported questions about dental fear and temperament was distributed. Results: A total of 3 % was found to have dental fear. Significant correlation between DFS scores and shyness were observed. Women had significantly higher mean in DFS scores and emotionality, compared to men. Males had significantly higher mean in the temperament activity. No significant associations were found between dental fear and foreign or Swedish background. Youths with a Swedish background had higher mean in sociability. Conclusion: The prevalence of dental fear was 3 % of the young people. The women had a higher score of DFS and emotionality. The men reported higher degree of activity. Young people with foreign background had a lower degree of sociability. A significant association was found between DFS scores and shyness.

  • 469.
    Zamani, Akram
    University of Borås, School of Engineering.
    Superabsorbent Polymers from the Cell Wall of Zygomycetes Fungi2010Doctoral thesis, monograph (Other academic)
    Abstract [en]

    The present thesis presents new renewable, antimicrobial and biodegradable superabsorbent polymers (SAPs), produced from the cell wall of zygomycetes fungi. The cell wall was characterized and chitosan, being one of the most important ingredients, was extracted, purified, and converted to SAP for use in disposable personal care products designed for absorption of different body fluids. The cell wall of zygomycetes fungi was characterized by subsequent hydrolysis with sulfuric and nitrous acids and analyses of the products. The main ingredients of the cell wall were found to be polyphosphates (4-20%) and copolymers of glucosamine and N-acetyl glucosamine, i.e. chitin and chitosan (45-85%). The proportion of each of these components was significantly affected by the fungal strain and also the cultivation conditions. Moreover, dual functions of dilute sulfuric acid in relation to chitosan, i.e. dissolution at high temperatures and precipitation at lowered temperatures, were discovered and thus used as a basis for development of a new method for extraction and purification of the fungal chitosan. Treatment of the cell wall with dilute sulfuric acid at room temperature resulted in considerable dissolution of the cell wall polyphosphates, while chitosan and chitin remained intact in the cell wall residue. Further treatment of this cell wall residue, with fresh acid at 120°C, resulted in dissolution of chitosan and its separation from the remaining chitin/chitosan of the cell wall skeleton which was not soluble in hot acid. Finally, the purified fungal chitosan (0.34 g/g cell wall) was recovered by precipitation at lowered temperatures and pH 8-10. The purity and the yield of fungal chitosan in the new method were significantly higher than that were obtained in the traditional acetic acid extraction method. As a reference to pure chitosan, SAP from shellfish chitosan, was produced by conversion of this biopolymer into water soluble carboxymethyl chitosan (CMCS), gelation of CMCS with glutaraldehyde in aqueous solutions (1-2%), and drying the resultant gel. Effects of carboxymethylation, gelation and drying conditions on the water binding capacity (WBC) of the final products, were investigated. Finally, choosing the best condition, a biological superabsorbent was produced from zygomycetes chitosan. The CMCS-based SAPs were able to absorb up to 200 g water/g SAP. The WBC of the best SAP in urine and saline solutions was 40 and 32 g/g respectively, which is comparable to the WBC of commercially acceptable SAPs under identical conditions (34-57 and 30-37 g/g respectively).

  • 470.
    Zamani, Akram
    et al.
    University of Borås, School of Engineering.
    Jeihanipour, Azam
    University of Borås, School of Engineering.
    Edebo, Lars
    Niklasson, Claes
    Taherzadeh, Mohammad J.
    University of Borås, School of Engineering.
    Determination of glucosamine and N-acetyl glucosamine in fungal cell walls2008In: Journal of Agricultural and Food Chemistry, ISSN 0021-8561, E-ISSN 1520-5118, Vol. 56, no 18, p. 8314-8318Article in journal (Refereed)
    Abstract [en]

    A new method was developed to determine glucosamine (GlcN) and N-acetyl glucosamine (GlcNAc) in materials containing chitin and chitosan, such as fungal cell walls. It is based on two steps of hydrolysis with (i) concentrated sulfuric acid at low temperature and (ii) dilute sulfuric acid at high temperature, followed by one-step degradation with nitrous acid. In this process, chitin and chitosan are converted into anhydromannose and acetic acid. Anhydromannose represents the sum of GlcN and GlcNAc, whereas acetic acid is a marker for GlcNAc only. The method showed recovery of 90.1% of chitin and 85.7-92.4% of chitosan from commercial preparations. Furthermore, alkali insoluble material (AIM) from biomass of three strains of zygomycetes, Rhizopus oryzae, Mucor indicus, and Rhizomucor pusillus, was analyzed by this method. The glucosamine contents of AIM from R. oryzae and M. indicus were almost constant (41.7 +/- 2.2% and 42.0 +/- 1.7%, respectively), while in R. pusillus, it decreased from 40.0 to 30.0% during cultivation from 1 to 6 days. The GlcNAc content of AIM from R. oryzae and R. pusillus increased from 24.9 to 31.0% and from 36.3 to 50.8%, respectively, in 6 days, while it remained almost constant during the cultivation of M. indicus (23.5 +/- 0.8%).

  • 471.
    Zazzi, Åsa
    KTH, School of Chemical Science and Engineering (CHE), Chemistry.
    Chlorite: Geochemical properties, Dissolution kinetcis and Ni(II) sorption2009Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    In Sweden, among other countries, a deep multi-barrier geological repository, KBS-3, is planned for the burial of nuclear waste. One of the barriers is identified as the grantic bedrock itself and in this environment chlorite is present at surfaces in fracture zones.

    This thesis is focused on characterisation of chlorite samples and studies of their dissolution and sorption behaviour, in order to verify chlorites capacity to retard possible radionuclide migration in the case of leaking canisters.

    Chlorite dissolution of has been studied in the pH interval 2-12, and as expected the dissolution is highest at acidic pH and at most alkaline pH, whereas dissolution is lowest at near neutral pH values. Chemical and physical properties of chlorites clearly influence the dissolution rates, and at steady-state dissolution rates in the interval 10-12 ‑ 10-13 mol g-1 s-1 was observed.

    Sorption studies were performed since Ni(II) is one of the important activation products in spent nuclear fuel and sorption data on minerals like chlorite are lacking. Ni(II) sorption onto chlorite was studied using batch technique as a function of; pH, concentration of Ni(II), ionic strength and solid concentrations. As expected, the sorption of Ni(II) onto chlorite was pH dependent, but not ionic strength dependent, with a sorption maximum at pH ~ 8, and with a Kd of ~ 103 cm3/g. This confirms that the Ni(II) sorption onto chlorite is primarily acting through surface complexation. The acid-base properties were determined by titrations and described by a non-electrostatical surface complexation model in FITEQL. Further, the sorption results were fit with a 2-pK NEM model and three surface complexes, Chl_OHNi2+, Chl_OHNi(OH)+ and Chl_OHNi(OH)2, gave the best fit using FITEQL.

  • 472.
    Zelenin, Sergey
    et al.
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology.
    Käller, M.
    Nazarov, A.
    Brismar, H.
    Russom, Aman
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology.
    High density custom microarrays formed by microcompartment amplification on glass surface2014In: 18th International Conference on Miniaturized Systems for Chemistry and Life Sciences, MicroTAS 2014, Chemical and Biological Microsystems Society , 2014, p. 1027-1029Conference paper (Refereed)
    Abstract [en]

    Compartmentalization of a single DNA molecule is necessary for digital amplification. In the present study we have developed a microscale isothermal amplification using exponential rolling circle amplification (RCA). RCA was performed in PDMS microcompartments on a microarray glass, with a volume of less than 1 pL. Resulting amplicons were attached to the glass surface and formed a custom array with the density of spots above 2,5 × 105 per cm2. Our technology can be applied for digital amplification of DNA or RNA from a variety of complex biological samples in a microchip format.

  • 473. Zerbetto, Mirco
    et al.
    Polimeno, Antonino
    Kotsyubynskyy, Dmytro
    Stockholm University, Faculty of Science, Department of Physical, Inorganic and Structural Chemistry.
    Ghalebani, Leila
    Stockholm University, Faculty of Science, Department of Physical, Inorganic and Structural Chemistry.
    Kowalewski, Jozef
    Stockholm University, Faculty of Science, Department of Physical, Inorganic and Structural Chemistry, Department of Physical Chemistry.
    Meirovitch, Eva
    Olsson, Ulrika
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Widmalm, Göran
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    An integrated approach to NMR spin relaxation in flexible biomolecules: Application to β-D-glucopyranosyl-(1→6)-α-D-mannopyranosyl-OMe2009In: Journal of Chemical Physics, ISSN 0021-9606, E-ISSN 1089-7690, Vol. 131, no 23, p. p234501-Article in journal (Refereed)
    Abstract [en]

    The description of the reorientational dynamics of flexible molecules is a challenging task, in particular when the rates of internal and global motions are comparable. The commonly used simple mode-decoupling models are based on the assumption of statistical independence between these motions. This assumption is not valid when the time scale separation between their rates is small, a situation that was found to arise in oligosaccharides in the context of certain internal motions. To make possible the interpretation of NMR spin relaxation data from such molecules, we developed a comprehensive approach generally applicable to flexible rotators with one internal degree of freedom. This approach integrates a stochastic description of coupled global tumbling and internal torsional motion, quantum chemical calculations of the local potential and the local geometry at the site of the restricted torsion, and hydrodynamics-based calculations of the diffusive properties. The method is applied to the disaccharide -D-Glcp-(16)--D-[6-13C]-Manp-OMe dissolved in a DMSO-d6/D2O cryosolvent. The experimental NMR relaxation parameters, associated with the 13CH2 probe residing at the glycosidic linkage, include 13C T1 and T2 and 13C-{1H} nuclear Overhauser enhancement (NOE) as well as longitudinal and transverse dipole-dipole cross-correlated relaxation rates, acquired in the temperature range of 253–293 K. These data are predicted successfully by the new theory with only the H–C–H angle allowed to vary. Previous attempts to fit these data using mode-decoupling models failed.

  • 474.
    Zhou, Ye
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Sensor Science and Molecular Physics . Linköping University, The Institute of Technology.
    Andersson, Olof
    Linköping University, Department of Physics, Chemistry and Biology, Sensor Science and Molecular Physics . Linköping University, The Institute of Technology.
    Lindberg, Peter
    Biacore AB, Rapsgatan 7, S-754 50, Uppsala, Sweden.
    Liedberg, Bo
    Linköping University, Department of Physics, Chemistry and Biology, Sensor Science and Molecular Physics . Linköping University, The Institute of Technology.
    Protein Microarrays on Carboxymethylated Dextran Hydrogels: Immobilization, Characterization and Application2004In: Microchimica Acta, ISSN 0026-3672, E-ISSN 1436-5073, Vol. 147, no 1-2, p. 21-30Article in journal (Refereed)
    Abstract [en]

    Tetraoctadecylammonium bromide (TOAB, (CH3(CH2)17)4N+Br) has been used to print temporary hydrophobic barriers on carboxymethylated dextran (CMD) hydrogels to create a generic platform for protein microarray applications. The primary reason for printing temporary hydrophobic barriers is to prevent cross-contamination and overflow during microdrop dispensing. Equally important is to eliminate the risk for non-specific binding to the barriers during analyte exposure. This has been accomplished by introducing a regeneration step that removes the barriers after ligand immobilization. The overall fabrication process was characterized by microscopic wetting, atomic force microscopy, imaging ellipsometry, fluorescence microscopy, surface plasmon microscopy and biospecific interaction analysis. A series of model proteins including transferrin, Protein A, anti-myoglobin and bovine serum albumin was spotted into the TOAB-defined areas under different experimental conditions, e.g. at increased humidity and reduced substrate temperature or with glycerol as an additive in the protein solution. Much emphasis was devoted to studies aiming at exploring the homogeneity and activity of the immobilized proteins. The printed barriers were removed after protein immobilization using tert-n-butyl alcohol (TBA). TBA was found to be a very efficient agent as compared to previously used salt regeneration solutions, and the regeneration time could be reduced from 30 to 10 minutes. Finally, the potential of using the well established CMD hydrogel chemistry as a platform for protein microarrays was exploited using surface plasmon microscopy.

  • 475.
    Zhu, Jun
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Biochemistry and Organic Chemistry.
    Dahlstrand, Christian
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Biochemistry and Organic Chemistry.
    Smith, Joshua R.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Biochemistry and Organic Chemistry.
    Villaume, Sebastien
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Biochemistry and Organic Chemistry.
    Ottosson, Henrik
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Biochemistry and Organic Chemistry.
    On the Importance of Clar Structures of Polybenzenoid Hydrocarbons as Revealed by the n-Contribution to the Electron Localization Function2010In: Symmetry, ISSN 2073-8994, E-ISSN 2073-8994, Vol. 2, no 3, p. 1653-1682Article in journal (Refereed)
    Abstract [en]

    The degree of p-electron (de)localization and aromaticity of a series of polybenzenoid hydrocarbons (PBHs) has been analyzed through the π-contribution to the electron localization function (ELFπ), calculated at the B3LYP/6-311G(d,p) hybrid density functional theory level. The extent of p-electron delocalization in the various hexagons of a PBH was determined through analysis of the bifurcation values of the ELFp basins (BV(ELFp)), the spans in the bifurcation values in each hexagon (ΔBV(ELFπ)), and the ring-closure bifurcation values of the ELFπ (RCBV(ELFπ)). These computed results were compared to the qualitative description of local aromaticities of the different hexagons in terms of Clar structures with p-sextets. Benzene, [18]annulene, and thirty two PBHs were analyzed at their equilibrium geometries, and benzene and triphenylene were also analyzed at bond length distorted structures. In general, the description of PBHs in terms of Clar valence structures is supported by the ELFp properties, although there are exceptions. For PBHs at their equilibrium geometries there is a clear sigmoidal relationship between the CC bond lengths and the amount of p-electron (de)localization at these bonds, however, this relationship is lost for bond distorted geometries. In the latter cases, we specifically examined benzene in D3h symmetric “1,3,5-cyclohexatriene” structures and triphenylene in eight different structures. From the distorted benzenes and triphenylenes it becomes clear that there is a distinct tendency for the p-electron network to retain delocalization (aromaticity). The ELFp analysis thus reveals an antidistortive rather than a distortive behavior of the p-electrons in these investigated compounds.

  • 476.
    Zhybak, Mykhailo T.
    et al.
    Linköping University, Faculty of Science & Engineering. Linköping University, Department of Physics, Chemistry and Biology. Institute of Molecular Biology and Genetics, NAS of Ukraine, Kyiv, 03680, Ukraine .
    Vagin, Mikhail Yu.
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, Department of Physics, Chemistry and Biology. Linköping University, Faculty of Science & Engineering.
    Beni, Valerio
    ACREO Swedish ICT, -601 74, Norrköping, SE, Sweden .
    Liu, Xianjie
    Linköping University, Department of Physics, Chemistry and Biology, Surface Physics and Chemistry. Linköping University, Faculty of Science & Engineering.
    Dempsey, Eithne
    Centre for Research in Electroanalytical Technologies, Department of Science, Institute of Technology Tallaght, Tallaght, Dublin, Ireland .
    Turner, Anthony P. F.
    Linköping University, Department of Physics, Chemistry and Biology, Biosensors and Bioelectronics. Linköping University, Faculty of Science & Engineering.
    Korpan, Yaroslav I.
    Institute of Molecular Biology and Genetics, NAS of Ukraine, Kyiv, 03680, Ukraine .
    Direct detection of ammonium ion by means of oxygen electrocatalysis at a copper-polyaniline composite on a screen-printed electrode.2016In: Microchimica Acta, ISSN 0026-3672, E-ISSN 1436-5073, Vol. 183, no 6, p. 1981-1987Article in journal (Refereed)
    Abstract [en]

    A novel electrocatalytic material for oxygen reduction, based on polyaniline in combinationwith copper, was developed and utilised for the direct voltammetric quantification of ammonium ions. Consecutive electrode modification by electrodeposited copper, a Nafion membrane and electropolymerised polyaniline resulted in an electrocatalytic composite material which the retained conductivity at neutral pH. Ammonia complex formation with Cu (I) caused the appearance of oxygen electrocatalysis, which was observed as an increase in cathodic current. This Faradaic phenomenon offered the advantage of direct voltammetric detection and was utilised for ammonium electroanalysis. The developed quantification protocol was applied for ammonium assay in human serum and compared with the routine approach for clinical analysis.

  • 477.
    Zuberovic, Aida
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Physical and Analytical Chemistry, Analytical Chemistry. Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Physical and Analytical Chemistry.
    Hanrieder, Jörg
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Physical and Analytical Chemistry, Analytical Chemistry. Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Physical and Analytical Chemistry.
    Hellman, Ulf
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Medicinska och farmaceutiska vetenskapsområdet, centrumbildningar mm , Ludwig Institute for Cancer Research.
    Bergquist, Jonas
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Physical and Analytical Chemistry, Analytical Chemistry. Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Physical and Analytical Chemistry.
    Wetterhall, Magnus
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Physical and Analytical Chemistry, Analytical Chemistry. Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Physical and Analytical Chemistry.
    Proteome profiling of human cerebrospinal fluid: exploring the potential of capillary electrophoresis with surface modified capillaries for analysis of complex biological samples.2008In: European journal of mass spectrometry, ISSN 1469-0667, E-ISSN 1751-6838, Vol. 14, no 4, p. 249-260Article in journal (Refereed)
    Abstract [en]

    A bottom-up proteomic approach, based on capillary electrophoresis (CE) in combination with matrix- assisted laser desorption/ionization tandem time-of-flight mass spectrometry (MALDI-ToF/ToF MS), was used to analyze immunoaffinity depleted human cerebrospinal fluid (CSF) and compare it with a non-depleted sample. After enzymatic digestion and desalting, the tryptic peptides were separated by CE using PolyE-323 modified capillaries and fractionated off-line onto MALDI target plates for further analysis by MALDI-MS and MS/MS. The protein profile of the depleted sample was compared with non depleted CSF. Overall, 85 proteins were identified with 95% significance in both samples. The significance scores for proposed biomarkers, such as amyloid-like protein 1 precursor, could be increased up to 12 times after the depletion. Other proteins, often suggested to be related to neurodegenerative diseases, like amyloid beta A4 protein precursor, superoxide dismutase and apolipoprotein E precursor could only be found in the depleted CSF samples. The effect of a derivatization of tryptic peptides with 2- methoxy-4,5-dihydro-1H-imidazole reagent for protein identification with MS was also employed to increase the number of identified proteins and the sequence coverages. The results presented in this study illustrate the benefit of combining a sample pre-fractionation step and a label's ability to enhance the ionization efficiency with the potential of CE using PolyE-323 modified capillaries in the analysis of complex samples. The straight-forward approach that provides speed and simplicity resulting in high-resolution separations and low sample consumption represents an easily applicable separation technique that can serve as a complement to other currently existing analytical approaches needed in modern proteomic analysis of clinically relevant samples.

  • 478.
    Zweigel, Catarina
    Linköping University, Department of Physics, Chemistry and Biology.
    Validering av metoder för analys av Cu, Fe och Na i processvatten med AAS-grafitugn2009Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Södra Cell Mörrum is one of the five paper pulp plants that are included in Södra Cell, and the paper pulp that is produced here is not only sold to Swedish paper mills. Most of the paper pulp is exported to different countries in Europe. In the manufacturing process the plant needs different kind of process water and there are guideline values for how much copper, iron and sodium this water is allowed to contain. Analyzes of this water is in the current situation done with an atomic absorption spectrometric instrument (AAS-instrument) with a flame.

     

    Measurements done with flame-AAS of samples that have concentrations near the guideline values for copper, iron and sodium, are not reliable. The reason for not being reliable is that the quantitation limits of these metals are higher than the limit values. An alternative method that should give more reliable values is to analyze with an AAS- instrument with a graphite furnace. The purpose of this project was to perform a method validation of the graphite furnace of the AAS-instrument in the analysis of Cu, Fe and Na. The focus of the project was to find the detection limits for each metal, study the variation and to see if it is possible to analyze these water samples with this technique.

     

    The concentrations of the calibration solutions is between 1-10 µg/l for Na, 5-25 µg/l for Cu and 2-20 µg/l for Fe.The detection limits for all metals were slightly below 1 µg/l and during the present circumstances in the laboratory; it would be difficult to get even lower detection limits. There are improvements that can be done to get to the even lower detection limits. The results from this work show that the variation in each sampling cup is very small but if you look at different sampling cups the variation could be large if the cups are not treated in the right way. Further validation analyzes like variation in between days needs to be done.

    It is possible to analyze these low concentrations of copper, iron and sodium in the water samples with the AAS- graphite furnace, but it is difficult because there are many factors that affect the results. Examples of such factors are the environment where the instrument is placed in the laboratory and the human factor. Further analyzes needs to be done to get a better view of how these factors affect the result.

  • 479.
    Åberg, Veronica
    et al.
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Norman, Fredrik
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Chorell, Erik
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Westermark, Andreas
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Olofsson, Anders
    Umeå University, Faculty of Medicine, Umeå Centre for Molecular Pathogenesis (UCMP) (Faculty of Medicine).
    Sauer-Eriksson, Elisabeth
    Umeå University, Faculty of Science and Technology, Umeå Centre for Molecular Pathogenesis (UCMP) (Faculty of Science and Technology).
    Almqvist, Fredrik
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Microwave-assisted decarboxylation of bicyclic 2-pyridone scaffolds and identification of A beta-peptide aggregation inhibitors2005In: Organic and biomolecular chemistry, ISSN 1477-0520, E-ISSN 1477-0539, Vol. 3, no 15, p. 2817-2823Article in journal (Refereed)
    Abstract [en]

    A reagent-free microwave-assisted decarboxylation procedure for carboxylic acid functionalized bicyclic 2-pyridones has been developed. This new method, based on microwave heating at 220 degrees C for 600 seconds in N-methyl pyrrolidone (NMP), proved to be practical and very efficient, resulting in decarboxylated 2-pyridones in near-quantitative yields. The decarboxylated products and the intermediate 2-pyridones in the form of carboxylic acid methyl esters and carboxylic acids were screened for their effect on A beta-peptide aggregation. Two out of the 21 2-pyridones described in this study inhibited amyloid formation of the Alzheimer A beta(1-40) peptide. The effect was seen even at a 4 : 1 ratio of 2-pyridone and monomeric A beta-peptide.

  • 480.
    Åkerstedt, Josefin
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Inorganic Chemistry.
    Tailored Reaction Media for the Synthesis of Subvalent Cluster Compounds2010Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Different synthetic approaches and modifications to reaction media have been applied in order to find new routes to the synthesis of main-group clusters and transition metal compounds. The focus has been on the Group 15 element bismuth and the transition metal palladium. The reactions performed have mainly been Lewis acid-base reactions and the characterization tools used X-ray diffraction and Raman spectroscopy.

    The Bi5[GaCl4]3 salt, previously known form synthesis using other reaction routes, has been isolated from GaCl3-dichloromethane media. The salt containing the subvalent naked bismuth polycation Bi53+ was isolated from the reduction of bismuth(III) chloride. Quantum chemical calculations on the interaction energies of the isolated bismuth cluster show the dichloromethane-cluster interaction energy to be higher than that between benzene and the cluster.

    Ionic liquids have, in addition to dichloromethane, been shown to work as alternative reaction media for room-temperature synthesis of the Bi5[GaCl4]3 salt. Three different classes of ionic liquids have been used; phosphonium-, imidazolium- and pyrrolidinium-based salts. The ionic liquids used have been treated with Lewis acids in order to promote cluster formation.

    In this work three new palladium sandwich compounds have also been isolated, using GaCl3-arene reaction media; [Pd2(Ga2Cl7)(C7H8)2], [Pd2(GaCl4)(C9H12)2]∙C9H12 and [Pd2(Ga2Cl7)(C6H5Cl)2]. Quantum chemical calculations on these palladium sandwiches show the chlorobenzene sandwiching ligands unexpectedly interacting more strongly with the dipalladium unit than the methyl substituted arenes.

  • 481.
    Åkerstedt, Josefin
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Applied Physical Chemistry.
    Gorlov, Mikhail
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Applied Physical Chemistry.
    Kloo, Lars
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Applied Physical Chemistry.
    Room-Temperature Synthesis of the Bi-5[GaCl4](3) Salt From Three Different Classes of Ionic Liquids2013In: Journal of cluster science, ISSN 1040-7278, E-ISSN 1572-8862, Vol. 24, no 1, p. 157-164Article in journal (Refereed)
    Abstract [en]

    Following the development in the synthesis of subvalent cluster compounds, we report on the use of three different classes of room-temperature ionic liquids for the synthesis of the pentabismuth-tris(tetragallate) salt, Bi-5[GaCl4](3), characterized by X-ray diffraction. The Bi-5[GaCl4](3) salt was prepared by reduction of BiCl3 using gallium metal in ionic liquid reaction media containing a strong Lewis acid, GaCl3. The ionic liquids; trihexyltetradecyl phosphonium chloride [Th-Td-P+]Cl-, 1-dodecyl-3-methylimidazolium chloride [Dod-Me-Im(+)]Cl- and N-butyl-N-methylpyrrolidinium chloride [Bu-Me-Pyrr(+)]Cl- from three of the main classes of ionic liquids were used in synthesis. Reactions using ionic liquids composed of the trihexyltetradecyl phosphonium cation [Th-Td-P+] and the anions; tetrafluoroborate [BF4 (-)], bis(trifluoro-methyl sulfonyl) imide [(Tf)(2)N-] and hexafluorophosphate [PF6 (-)] were also investigated.

  • 482.
    Åkerstedt, Josefin
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Inorganic Chemistry (closed 20110630).
    Gorlov, Mikhail
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Kloo, Lars
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Inorganic Chemistry (closed 20110630).
    Synthesis of Bi5[GaCl4]3 from room-temperature ionic liquid reaction mediaManuscript (preprint) (Other academic)
  • 483.
    Åkerstedt, Josefin
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Applied Physical Chemistry.
    Rosdahl, Jan
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Applied Physical Chemistry.
    Persson, Per
    Umeå University.
    Kloo, Lars
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Applied Physical Chemistry.
    Arsenic Clusters in Solution: An Experimental and A Priori Theoretical EXAFS StudyManuscript (preprint) (Other academic)
  • 484.
    Åkerstedt, Josefin
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Applied Physical Chemistry.
    Ruck, M.
    Kloo, Lars
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Applied Physical Chemistry.
    Long, J. R.
    Tungsten Chloride W3Cl10(CH3CN)3 fromRoom-temperature Synthesis in Ionic liquid using an Organic Co-solventManuscript (preprint) (Other academic)
  • 485.
    Örnberg, Andreas
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Corrosion Science.
    Pan, Jinshan
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Corrosion Science.
    Leygraf, Christofer
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Corrosion Science.
    Electrochemical study of tantalum as substrate for pacemaker electrodesIn: Journal of the Electrochemical Society, ISSN 0013-4651, E-ISSN 1945-7111Article in journal (Other academic)
  • 486.
    Östberg, Tomas L
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Jonsson, A P
    Lundström, Ulla
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Bylund, Dan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Effects of whey addition on the biodegradation of n-hexadecane, n-octadecane and phenanthrene in diesel fuel contaminated soilManuscript (preprint) (Other academic)
  • 487.
    Österberg, Ida
    Mälardalen University, School of Education, Culture and Communication.
    Hellre fria än fälla: En studie i utformning och bedömning av ett prov i kemisk jämvikt2008Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    I detta examensarbete undersöktes hur ett kemiprov inom området kemisk jämvikt utformades och bedömdes på en gymnasieskola i Mellansverige. De två lärarna som utformade och bedömde provet intervjuades och fick svara på frågor via e- mail. Både intervjudata och frågorna via e-mail kategoriserades med hjälp av Selgheds (2006) kategorier rörande synsätt på betygsystemet. Resultatet visade att lärarna har olika synsätt på både provets utformning och bedömning trots att dem tillsammans konstruerat både prov och facit. Lärarna täckte med detta prov flera av de kända missuppfattningar som den didaktiska forskningen funnit, även om det inte var på ett systematiskt sätt. Istället visade resultatet att det fanns risk att missförstånd skall uppstå. Denna undersökning kan kompletteras med elev- och undervisningsperspektivet för att undersöka vilka konsekvenser det får om lärarna behandlar den didaktiska forskningen mer systematiskt.

  • 488.
    Östergren-Lundén, Gunnel
    et al.
    Wallenberg Laboratory for Cardiovascular Research, The Sahlgrenska Academy at Göteborg University, Göteborg, Sweden.
    Olivas, Raquel G.
    Departamento de Biologı́a Celular, Universitat de Barcelona, Barcelona, Spain.
    Eftekhari, Pierre
    UPR9021 C.N.R.S., Immunologie et Chimie Thérapeutiques, I.B.M.C., Strasbourg, France.
    Krettek, Alexandra
    Wallenberg Laboratory for Cardiovascular Research, The Sahlgrenska Academy at Göteborg University, Göteborg, Sweden.
    Sanjuan, Xavier
    Departamento de Biologı́a Celular, Universitat de Barcelona, Barcelona, Spain.
    Fager, Gunnar
    Wallenberg Laboratory for Cardiovascular Research, The Sahlgrenska Academy at Göteborg University, Göteborg, Sweden.
    Vilaró, Senén
    Departamento de Biologı́a Celular, Universitat de Barcelona, Barcelona, Spain.
    Lustig, Florentyna
    Wallenberg Laboratory for Cardiovascular Research, The Sahlgrenska Academy at Göteborg University, Göteborg, Sweden.
    Hoebeke, Johan
    UPR9021 C.N.R.S., Immunologie et Chimie Thérapeutiques, I.B.M.C., Strasbourg, France.
    Characterisation and application of antibodies specific for the long platelet-derived growth factor A and B chains2004In: International Journal of Biochemistry and Cell Biology, ISSN 1357-2725, E-ISSN 1878-5875, Vol. 36, no 11, p. 2226-2241Article in journal (Refereed)
    Abstract [en]

    The platelet-derived growth factor (PDGF) family comprises important mitogens for mesenchymal cells. The active dimeric form of PDGF consists of four structurally related A, B, C, and D chains. All PDGF-variants bind to PDGF-receptors. The A and B chains occur with and without basic C-terminal amino acid extensions as long (A(L) and B(L)) and short (A(S) and B(S)) isoforms. PDGF-A and -B form homo- or heterodimers. The biological relevance of short and long isoforms is unknown, although it may relate to different affinities for glycosaminoglycans of the cell glycocalix and intercellular matrix. Commercially available anti-PDGF-A and anti-PDGF-B antibodies cannot discriminate between the short and the long isoforms. Thus, to investigate the function of the long and short isoforms, we raised antibodies specific for the long A and B chain isoforms. The antibodies were affinity-purified and their properties analysed by surface plasmon resonance. Inhibition studies with different PDGF homodimers and dot-blot studies proved their high specificity for the respective isoforms. Both antibodies recognised the target PDGF homodimers complexed to the glycocalix of human arterial smooth muscle cells and human monocyte-derived macrophages. By using these specific antibodies, we were able to confirm at the protein level the synthesis of PDGF-A and -B during differentiation of human monocyte-derived macrophages and to demonstrate the presence of the PDGF-A(L) and PDGF-B(L) isoforms in human arterial tissue.

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