1. |
- Palica, Katarzyna, 1992-, et al.
(author)
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Metallo-β-Lactamase Inhibitor Phosphonamidate Monoesters
- 2022
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In: ACS Omega. - : American Chemical Society (ACS). - 2470-1343. ; 7:5, s. 4550-4562
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Journal article (peer-reviewed)abstract
- Being the second leading cause of death and the leading cause of disability-adjusted life years worldwide, infectious diseases remain─contrary to earlier predictions─a major consideration for the public health of the 21st century. Resistance development of microbes to antimicrobial drugs constitutes a large part of this devastating problem. The most widely spread mechanism of bacterial resistance operates through the degradation of existing β-lactam antibiotics. Inhibition of metallo-β-lactamases is expected to allow the continued use of existing antibiotics, whose applicability is becoming ever more limited. Herein, we describe the synthesis, the metallo-β-lactamase inhibition activity, the cytotoxicity studies, and the NMR spectroscopic determination of the protein binding site of phosphonamidate monoesters. The expression of single- and double-labeled NDM-1 and its backbone NMR assignment are also disclosed, providing helpful information for future development of NDM-1 inhibitors. We show phosphonamidates to have the potential to become a new generation of antibiotic therapeutics to combat metallo-β-lactamase-resistant bacteria.
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2. |
- DAWODY, JAZAER, 1959, et al.
(author)
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E4-Mistra, a research program for the development of an energy efficient low emission exhaust aftertreatment system for heavy duty vehicles
- 2012
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In: World Renewable Energy Forum, WREF 2012, Including World Renewable Energy Congress XII and Colorado Renewable Energy Society (CRES) Annual Conference. - : American Solar Energy Society. - 9781622760923 ; , s. 4530-4536
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Conference paper (peer-reviewed)abstract
- This paper presents a unique system approach applied in a joint academic - industrial research program, E4 Mistra, to reach the goals of energy efficiency and low emissions exhaust aftertreatment system for heavy duty vehicles. The high energy efficiency is achieved by heat recuperation, on-board hydrogen production for use in both an auxiliary power unit and for NOx reduction and by finding new solutions for making the after-treatment system active at low exhaust temperatures. To reach low particulate emissions a mechanical filter using a sintered metal filter is developed. Low NOx emissions are achieved by an efficient NOx reduction catalyst. The system is based on four technological advances: Thermoelectric material s for heat recuperation, catalytic reduction of NOx over innovative catalyst substrates using hydrocarbons from the fuel and H2 from a high efficiency fuel reformer, and particulate filtration over a porous metal filter.
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3. |
- Palica, Katarzyna, 1992-, et al.
(author)
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α-Aminophosphonate inhibitors of metallo-β-lactamases NDM-1 and VIM-2
- 2023
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In: RSC Medicinal Chemistry. - : Royal Society of Chemistry. - 2632-8682. ; 14:11, s. 2277-2300
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Journal article (peer-reviewed)abstract
- The upswing of antibiotic resistance is an escalating threat to human health. Resistance mediated by bacterial metallo-β-lactamases is of particular concern as these enzymes degrade β-lactams, our most frequently prescribed class of antibiotics. Inhibition of metallo-β-lactamases could allow the continued use of existing β-lactam antibiotics, such as penicillins, cephalosporins and carbapenems, whose applicability is becoming ever more limited. The design, synthesis, and NDM-1, VIM-2, and GIM-1 inhibitory activities (IC50 4.1–506 μM) of a series of novel non-cytotoxic α-aminophosphonate-based inhibitor candidates are presented herein. We disclose the solution NMR spectroscopic and computational investigation of their NDM-1 and VIM-2 binding sites and binding modes. Whereas the binding modes of the inhibitors are similar, VIM-2 showed a somewhat higher conformational flexibility, and complexed a larger number of inhibitor candidates in more varying binding modes than NDM-1. Phosphonate-type inhibitors may be potential candidates for development into therapeutics to combat metallo-β-lactamase resistant bacteria.
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4. |
- M. Gavelin, Hanna, 1982-, et al.
(author)
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Mental fatigue, cognitive performance and autonomic response following sustained mental activity in clinical burnout
- 2023
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In: Biological Psychology. - : Elsevier B.V.. - 0301-0511 .- 1873-6246. ; 183
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Journal article (peer-reviewed)abstract
- ObjectiveTo investigate the effects of sustained mental activity on perceptions of mental fatigue, cognitive performance, and autonomic response in patients with clinical burnout as compared to a healthy control group.MethodsPatients with clinical burnout (n = 30) and healthy control participants (n = 30) completed a 3-hour test session, in which they were administered a set of cognitive tests before and after an effortful cognitive task with concurrent sound exposure. Perceptions of mental fatigue and task demands (mental effort and concentration difficulties) were assessed repeatedly over the course of the test session. Heart rate variability was recorded to index autonomic response.ResultsIn comparison with controls, perceived mental fatigue increased earlier in the session for the clinical burnout group and did not recover following a short rest period. Throughout the session, patients rated the tasks as more demanding and showed less improvement on measures of attention and processing speed, inhibition and working memory. While autonomic responses were initially comparable, there was a unique decrease in high-frequency heart rate variability in the clinical burnout group after extended testing and exposure.ConclusionPatients with clinical burnout are affected differently than healthy controls by sustained mental activity, as reflected by ratings of perceived mental fatigue, aspects of cognitive performance and autonomic response. Further investigation into the role of autonomic regulation in relation to cognitive symptoms in clinical burnout is warranted.
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5. |
- Ahlryd, Sara, et al.
(author)
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Stärkta skolbibliotek kräver stora satsningar på att utbilda bibliotekarier
- 2024
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Other publication (pop. science, debate, etc.)abstract
- Debatt: Äntligen kom den: regeringens lagrådsremiss som ska stärka elevers rätt till skolbibliotek. Vi som utbildar blivande bibliotekarier gläds över remissen som i linje med forskning visar skolbibliotekets och skolbibliotekariers betydelse för elevers lärande. Samtidigt konstaterar vi att en lagändring också måste följas av riktade satsningar på landets bibliotekarieutbildningar för att förverkligas, skriver 16 biblioteksforskare.
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6. |
- Andersson, Hanna, 1991-, et al.
(author)
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Anchoring effect in judgments of objective fact and subjective preference
- 2021
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In: Food Quality and Preference. - : Elsevier. - 0950-3293 .- 1873-6343. ; 88
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Journal article (peer-reviewed)abstract
- The way by which various sources of external information interact in their effects on judgment is rarely investigated. Here, we report two experiments that examine how two sources of external information—an anchor (a reference price) and an eco-label—influence judgments of an objective fact (product price) and a subjective preference (willingness-to-pay for the product). Participants’ price judgments were drawn in the direction of the anchor point, whereas the eco-label resulted in higher judgments of objective fact (Experiment 1) but did not influence subjective preference (Experiment 2). Interestingly, the eco-label seemed to strengthen the effect of the high anchor in judgments of objective fact. Further, participants with higher environmental concern answered a higher price on the subjective preference questions when they received a high anchor, as well as a lower price when they received a low anchor in comparison to the low environmental concern group. This study demonstrates that various external information sources can strengthen each other’s effects on consumer belief about products, while the effects are weaker for consumers’ preferences. The implications of the results for decision making are discussed.
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7. |
- Andersson, Hanna, 1979, et al.
(author)
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Assessing the Ability of Spectroscopic Methods to Determine the Difference in the Folding Propensities of Highly Similar beta-Hairpins
- 2017
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In: Acs Omega. - : American Chemical Society (ACS). - 2470-1343. ; 2:2, s. 508-516
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Journal article (peer-reviewed)abstract
- We have evaluated the ability of nuclear magnetic resonance (NMR) and circular dichroism (CD) spectroscopies to describe the difference in the folding propensities of two structurally highly similar cyclic beta-hairpins, comparing the outcome to that of molecular dynamics simulations. NAMFIS-type NMR ensemble analysis and CD spectroscopy were observed to accurately describe the consequence of altering a single interaction site, whereas a single-site C-13 NMR chemical shift melting curve-based technique was not.
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8. |
- Andersson, Hanna, Dr. 1979-, et al.
(author)
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Binding of 2-(Triazolylthio)acetamides to Metallo-beta-lactamase CcrA Determined with NMR
- 2020
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In: ACS Omega. - : American Chemical Society (ACS). - 2470-1343. ; 5:34, s. 21570-21578
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Journal article (peer-reviewed)abstract
- Metallo-beta-lactamase (MBL)-producing bacteria resistant to beta-lactam antibiotics are a serious threat to human health. Despite great efforts and important progress in the discovery of MBL inhibitors (MBLIs), there is none in clinical use. Herein, inhibitor complexes of the MBL CcrA were investigated by NMR spectroscopy to provide perspectives on the further development of 2-(triazolylthio)acetamide-type MBLIs. By using the NMR-based chemical shift perturbation (CSP) and direction of CSP methodologies together with molecular docking, the spatial orientation of three compounds in the CcrA active site was investigated (4-6). Inhibitor 6 showed the best binding affinity (K-d approximate to 2.3 +/- 0.3 mu M), followed by 4 (K-d approximate to 11 +/- 11 mu M) and 5 (K-d = 34 +/- 43 mu M), as determined from the experimental NMR data. Based on the acquired knowledge, analogues of other MBLIs (1-3) were designed and evaluated in silico with the purpose of examining a strategy for promoting their interactions with the catalytic zinc ions.
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9. |
- Andersson, Hanna, 1979-
(author)
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Design and Synthesis of Angiotensin IV Peptidomimetics Targeting the Insulin-Regulated Aminopeptidase (IRAP)
- 2010
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Doctoral thesis (other academic/artistic)abstract
- Peptidomimetics derived from the bioactive hexapeptide angiotensin IV (Ang IV, Val1-Tyr2-Ile3-His4-Pro5-Phe6) have been designed and synthesized. These peptidomimetics are aimed at inhibiting the insulin-regulated amino peptidase (IRAP), also known as the AT4 receptor. This membrane-bound zinc-metallopeptidase is currently under investigation regarding its potential as a target for cognitive enhancers. The work presented herein was based on stepwise replacement of the amino acid residues in Ang IV by natural and unnatural amino acids, non-peptidic building blocks, and also on the introduction of conformational constraints. Initially, we focused on the introduction of secondary structure mimetics and backbone mimetics. The C-terminal tripeptide His-Pro-Phe was successfully replaced by a γ-turn mimetic scaffold, 2-(aminomethyl)phenylacetic acid (AMPA), which was coupled via an amide bond to the carboxyl terminus of Val-Tyr-Ile. Substitution of Val-Tyr-Ile, Val-Tyr, Tyr-Ile and Tyr, respectively, by 4-hydroxydiphenylmethane scaffolds comprising a 1,3,5-substituted benzene ring as a central moiety unfortunately rendered peptidomimetics that were less potent than Ang IV. The subsequent approach involved the introduction of conformational constraints into Val-Tyr-Ile-AMPA by replacing Val and Ile by amino acid residues appropriate for disulfide cyclization or ring-closing metathesis. Chemically diverse structures encompassing an N-terminal 13- or 14-membered macrocyclic tripeptide and a C-terminal non-peptidic moiety were developed. Tyr2 and AMPA were modified to acquire further knowledge about the structure-activity relationships and, in addition, to improve the metabolic stability and reduce the polarity. Several of the compounds displayed a high capacity to inhibit IRAP and exhibited Ki values in the low nanomolar range. Hence, the new compounds were more than ten times more potent than the parent peptide Ang IV. Enhanced selectivity over the closely related aminopeptidase N (AP-N) was achieved, as well as improved stability against proteolysis by metallopeptidases present in the assays. However, additional investigations are required to elucidate the bioactive conformation(s) of the relatively flexible N-terminal macrocycles. The compounds presented in this thesis have provided important information on structure-activity relationships regarding the interaction of Ang IV-related pseudopeptides and peptidomimetics with IRAP. The best compounds in the series constitute important starting points for further discovery of Ang IV peptidomimetics suitable as tools in the investigation of IRAP and other potential targets for Ang IV. The literature presents strong support for the hypothesis that drug-like IRAP inhibitors would serve as a new type of future cognitive enhancers with potential use in the treatment of cognitive disorders, e.g. Alzheimer’s disease.
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10. |
- Andersson, Hanna, Dr. 1979-, et al.
(author)
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Discovery of inhibitors of insulin-regulated aminopeptidase as cognitive enhancers
- 2012
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In: International Journal of Hypertension. - : Hindawi Limited. - 2090-0384 .- 2090-0392. ; 2012, s. 789671-
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Research review (peer-reviewed)abstract
- The hexapeptide angiotensin IV (Ang IV) is a metabolite of angiotensin II (Ang II) and plays a central role in the brain. It was reported more than two decades ago that intracerebroventricular injection of Ang IV improved memory and learning in the rat. Several hypotheses have been put forward to explain the positive effects of Ang IV and related analogues on cognition. It has been proposed that the insulin-regulated aminopeptidase (IRAP) is the main target of Ang IV. This paper discusses progress in the discovery of inhibitors of IRAP as potential enhancers of cognitive functions. Very potent inhibitors of the protease have been synthesised, but pharmacokinetic issues (including problems associated with crossing the blood-brain barrier) remain to be solved. The paper also briefly presents an overview of the status in the discovery of inhibitors of ACE and renin, and of AT1R antagonists and AT2R agonists, in order to enable other discovery processes within the RAS system to be compared. The paper focuses on the relationship between binding affinities/inhibition capacity and the structures of the ligands that interact with the target proteins.
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