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  1. Article ; Online: Predicting and prioritizing genetic diversity outcomes of animal translocations

    Matthew M. Smith / Clare G. Knife / Daniel Eklund / Brian Heeringa / Jonathan N. Pauli

    Conservation Science and Practice, Vol 5, Iss 6, Pp n/a-n/a (2023)

    2023  

    Keywords augmentation ; connectivity ; genetic diversity ; reintroductions ; sharp‐tailed grouse ; simulations ; Ecology ; QH540-549.5 ; General. Including nature conservation ; geographical distribution ; QH1-199.5
    Language English
    Publishing date 2023-06-01T00:00:00Z
    Publisher Wiley
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  2. Article ; Online: Development of Electrophoretic Deposition Prototype for Continuous Production of Carbon Nanotube-Modified Carbon Fiber Fabrics Used in High-Performance Multifunctional Composites

    Guan Gong / Birgitha Nyström / Erik Sandlund / Daniel Eklund / Maxime Noël / Robert Westerlund / Sofia Stenberg / Liva Pupure / Andrejs Pupurs / Roberts Joffe

    Fibers, Vol 6, Iss 4, p

    2018  Volume 71

    Abstract: An electrophoretic deposition (EPD) prototype was developed aiming at the continuous production of carbon nanotube (CNT) deposited carbon fiber fabric. Such multi-scale reinforcement was used to manufacture carbon fiber-reinforced polymer (CFRP) ... ...

    Abstract An electrophoretic deposition (EPD) prototype was developed aiming at the continuous production of carbon nanotube (CNT) deposited carbon fiber fabric. Such multi-scale reinforcement was used to manufacture carbon fiber-reinforced polymer (CFRP) composites. The overall objective was to improve the mechanical performance and functionalities of CFRP composites. In the current study, the design concept and practical limit of the continuous EPD prototype, as well as the flexural strength and interlaminar shear strength, were the focus. Initial mechanical tests showed that the flexural stiffness and strength of composites with the developed reinforcement were significantly reduced with respect to the composites with pristine reinforcement. However, optical microscopy study revealed that geometrical imperfections, such as waviness and misalignment, had been introduced into the reinforcement fibers and/or bundles when being pulled through the EPD bath, collected on a roll, and dried. These defects are likely to partly or completely shadow any enhancement of the mechanical properties due to the CNT deposit. In order to eliminate the effect of the discovered defects, the pristine reinforcement was subjected to the same EPD treatment, but without the addition of CNT in the EPD bath. When compared with such water-treated reinforcement, the CNT-deposited reinforcement clearly showed a positive effect on the flexural properties and interlaminar shear strength of the composites. It was also discovered that CNTs agglomerate with time under the electric field due to the change of ionic density, which is possibly due to the electrolysis of water (for carboxylated CNT aqueous suspension without surfactant) or the deposition of ionic surfactant along with CNT deposition (for non-functionalized CNT aqueous suspension with surfactant). Currently, this sets time limits for the continuous deposition.
    Keywords electrophoretic deposition ; carbon nanotube ; multi-scale carbon reinforcement ; multifunctional composites ; Chemicals: Manufacture ; use ; etc ; TP200-248 ; Textile bleaching ; dyeing ; printing ; TP890-933 ; Biology (General) ; QH301-705.5 ; Physics ; QC1-999
    Subject code 620
    Language English
    Publishing date 2018-09-01T00:00:00Z
    Publisher MDPI AG
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  3. Article ; Online: Human macrophages infected with a high burden of ESAT-6-expressing M. tuberculosis undergo caspase-1- and cathepsin B-independent necrosis.

    Amanda Welin / Daniel Eklund / Olle Stendahl / Maria Lerm

    PLoS ONE, Vol 6, Iss 5, p e

    2011  Volume 20302

    Abstract: Mycobacterium tuberculosis (Mtb) infects lung macrophages, which instead of killing the pathogen can be manipulated by the bacilli, creating an environment suitable for intracellular replication and spread to adjacent cells. The role of host cell death ... ...

    Abstract Mycobacterium tuberculosis (Mtb) infects lung macrophages, which instead of killing the pathogen can be manipulated by the bacilli, creating an environment suitable for intracellular replication and spread to adjacent cells. The role of host cell death during Mtb infection is debated because the bacilli have been shown to be both anti-apoptotic, keeping the host cell alive to avoid the antimicrobial effects of apoptosis, and pro-necrotic, killing the host macrophage to allow infection of neighboring cells. Since mycobacteria activate the NLRP3 inflammasome in macrophages, we investigated whether Mtb could induce one of the recently described inflammasome-linked cell death modes pyroptosis and pyronecrosis. These are mediated through caspase-1 and cathepsin-B, respectively. Human monocyte-derived macrophages were infected with virulent (H37Rv) Mtb at a multiplicity of infection (MOI) of 1 or 10. The higher MOI resulted in strongly enhanced release of IL-1β, while a low MOI gave no IL-1β response. The infected macrophages were collected and cell viability in terms of the integrity of DNA, mitochondria and the plasma membrane was determined. We found that infection with H37Rv at MOI 10, but not MOI 1, over two days led to extensive DNA fragmentation, loss of mitochondrial membrane potential, loss of plasma membrane integrity, and HMGB1 release. Although we observed plasma membrane permeabilization and IL-1β release from infected cells, the cell death induced by Mtb was not dependent on caspase-1 or cathepsin B. It was, however, dependent on mycobacterial expression of ESAT-6. We conclude that as virulent Mtb reaches a threshold number of bacilli inside the human macrophage, ESAT-6-dependent necrosis occurs, activating caspase-1 in the process.
    Keywords Medicine ; R ; Science ; Q
    Subject code 570
    Language English
    Publishing date 2011-01-01T00:00:00Z
    Publisher Public Library of Science (PLoS)
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  4. Article ; Online: Replication rates of Mycobacterium tuberculosis in human macrophages do not correlate with mycobacterial antibiotic susceptibility.

    Johanna Raffetseder / Elsje Pienaar / Robert Blomgran / Daniel Eklund / Veronika Patcha Brodin / Henrik Andersson / Amanda Welin / Maria Lerm

    PLoS ONE, Vol 9, Iss 11, p e

    2014  Volume 112426

    Abstract: The standard treatment of tuberculosis (TB) takes six to nine months to complete and this lengthy therapy contributes to the emergence of drug-resistant TB. TB is caused by Mycobacterium tuberculosis (Mtb) and the ability of this bacterium to switch to a ...

    Abstract The standard treatment of tuberculosis (TB) takes six to nine months to complete and this lengthy therapy contributes to the emergence of drug-resistant TB. TB is caused by Mycobacterium tuberculosis (Mtb) and the ability of this bacterium to switch to a dormant phenotype has been suggested to be responsible for the slow clearance during treatment. A recent study showed that the replication rate of a non-virulent mycobacterium, Mycobacterium smegmatis, did not correlate with antibiotic susceptibility. However, the question whether this observation also holds true for Mtb remains unanswered. Here, in order to mimic physiological conditions of TB infection, we established a protocol based on long-term infection of primary human macrophages, featuring Mtb replicating at different rates inside the cells. During conditions that restricted Mtb replication, the bacterial phenotype was associated with reduced acid-fastness. However, these phenotypically altered bacteria were as sensitive to isoniazid, pyrazinamide and ethambutol as intracellularly replicating Mtb. In support of the recent findings with M. smegmatis, we conclude that replication rates of Mtb do not correlate with antibiotic tolerance.
    Keywords Medicine ; R ; Science ; Q
    Language English
    Publishing date 2014-01-01T00:00:00Z
    Publisher Public Library of Science (PLoS)
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  5. Article ; Online: Apoptotic neutrophils augment the inflammatory response to Mycobacterium tuberculosis infection in human macrophages.

    Henrik Andersson / Blanka Andersson / Daniel Eklund / Eyler Ngoh / Alexander Persson / Kristoffer Svensson / Maria Lerm / Robert Blomgran / Olle Stendahl

    PLoS ONE, Vol 9, Iss 7, p e

    2014  Volume 101514

    Abstract: Macrophages in the lung are the primary cells being infected by Mycobacterium tuberculosis (Mtb) during the initial manifestation of tuberculosis. Since the adaptive immune response to Mtb is delayed, innate immune cells such as macrophages and ... ...

    Abstract Macrophages in the lung are the primary cells being infected by Mycobacterium tuberculosis (Mtb) during the initial manifestation of tuberculosis. Since the adaptive immune response to Mtb is delayed, innate immune cells such as macrophages and neutrophils mount the early immune protection against this intracellular pathogen. Neutrophils are short-lived cells and removal of apoptotic cells by resident macrophages is a key event in the resolution of inflammation and tissue repair. Since anti-inflammatory activity is not compatible with effective immunity to intracellular pathogens, we therefore investigated how uptake of apoptotic neutrophils modulates the function of Mtb-activated human macrophages. We show that Mtb infection exerts a potent proinflammatory activation of human macrophages with enhanced gene activation and release of proinflammatory cytokines and that this response was augmented by apoptotic neutrophils. The enhanced macrophage response is linked to apoptotic neutrophil-driven activation of the NLRP3 inflammasome and subsequent IL-1β signalling. We also demonstrate that apoptotic neutrophils not only modulate the inflammatory response, but also enhance the capacity of infected macrophages to control intracellular growth of virulent Mtb. Taken together, these results suggest a novel role for apoptotic neutrophils in the modulation of the macrophage-dependent inflammatory response contributing to the early control of Mtb infection.
    Keywords Medicine ; R ; Science ; Q
    Subject code 616
    Language English
    Publishing date 2014-01-01T00:00:00Z
    Publisher Public Library of Science (PLoS)
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  6. Article ; Online: Reduced susceptibility of clinical strains of Mycobacterium tuberculosis to reactive nitrogen species promotes survival in activated macrophages.

    Jonna Idh / Blanka Andersson / Maria Lerm / Johanna Raffetseder / Daniel Eklund / Hanna Woksepp / Jim Werngren / Mikael Mansjö / Tommy Sundqvist / Olle Stendahl / Thomas Schön

    PLoS ONE, Vol 12, Iss 7, p e

    2017  Volume 0181221

    Abstract: Drugs such as isoniazid (INH) and pretomanid (PRT), used against Mycobacterium tuberculosis are active partly through generation of reactive nitrogen species (RNS). The aim of this study was to explore variability in intracellular susceptibility to ... ...

    Abstract Drugs such as isoniazid (INH) and pretomanid (PRT), used against Mycobacterium tuberculosis are active partly through generation of reactive nitrogen species (RNS). The aim of this study was to explore variability in intracellular susceptibility to nitric oxide (NO) in clinical strains of M. tuberculosis.Luciferase-expressing clinical M. tuberculosis strains with or without INH resistance were exposed to RNS donors (DETA/NO and SIN-1) in broth cultures and bacterial survival was analysed by luminometry. NO-dependent intracellular killing in a selection of strains was assessed in interferon gamma/lipopolysaccharide-activated murine macrophages using the NO inhibitor L-NMMA.When M. tuberculosis H37Rv was compared to six clinical isolates and CDC1551, three isolates with inhA mediated INH resistance showed significantly reduced NO-susceptibility in broth culture. All strains showed a variable but dose-dependent susceptibility to RNS donors. Two clinical isolates with increased susceptibility to NO exposure in broth compared to H37Rv were significantly inhibited by activated macrophages whereas there was no effect on growth inhibition when activated macrophages were infected by clinical strains with higher survival to NO exposure in broth. Furthermore, the most NO-tolerant clinical isolate showed increased resistance to PRT both in broth culture and the macrophage model compared to H37Rv in the absence of mutational resistance in genes associated to reduced susceptibility against PRT or NO.In a limited number of clinical M. tuberculosis isolates we found a significant difference in susceptibility to NO between clinical isolates, both in broth cultures and in macrophages. Our results indicate that mycobacterial susceptibility to cellular host defence mechanisms such as NO need to be taken into consideration when designing new therapeutic strategies.
    Keywords Medicine ; R ; Science ; Q
    Language English
    Publishing date 2017-01-01T00:00:00Z
    Publisher Public Library of Science (PLoS)
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  7. Article ; Online: Dynamic Response Genes in CD4+ T Cells Reveal a Network of Interactive Proteins that Classifies Disease Activity in Multiple Sclerosis

    Sandra Hellberg / Daniel Eklund / Danuta R. Gawel / Mattias Köpsén / Huan Zhang / Colm E. Nestor / Ingrid Kockum / Tomas Olsson / Thomas Skogh / Alf Kastbom / Christopher Sjöwall / Magnus Vrethem / Irene Håkansson / Mikael Benson / Maria C. Jenmalm / Mika Gustafsson / Jan Ernerudh

    Cell Reports, Vol 16, Iss 11, Pp 2928-

    2016  Volume 2939

    Abstract: Multiple sclerosis (MS) is a chronic inflammatory disease of the CNS and has a varying disease course as well as variable response to treatment. Biomarkers may therefore aid personalized treatment. We tested whether in vitro activation of MS patient- ... ...

    Abstract Multiple sclerosis (MS) is a chronic inflammatory disease of the CNS and has a varying disease course as well as variable response to treatment. Biomarkers may therefore aid personalized treatment. We tested whether in vitro activation of MS patient-derived CD4+ T cells could reveal potential biomarkers. The dynamic gene expression response to activation was dysregulated in patient-derived CD4+ T cells. By integrating our findings with genome-wide association studies, we constructed a highly connected MS gene module, disclosing cell activation and chemotaxis as central components. Changes in several module genes were associated with differences in protein levels, which were measurable in cerebrospinal fluid and were used to classify patients from control individuals. In addition, these measurements could predict disease activity after 2 years and distinguish low and high responders to treatment in two additional, independent cohorts. While further validation is needed in larger cohorts prior to clinical implementation, we have uncovered a set of potentially promising biomarkers.
    Keywords Biology (General) ; QH301-705.5
    Subject code 570
    Language English
    Publishing date 2016-09-01T00:00:00Z
    Publisher Elsevier
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  8. Article: Antimycobacterial activity of selected medicinal plants traditionally used in Sudan to treat infectious diseases

    Abuzeid, Nadir / Asaad Khalid / Daniel Eklund / Elsje Pienaar / Haidar A. AlGadir / Henrik Andersson / Johanna Raffetseder / M. Ahmed Mesaik / Maria Lerm / Marie Larsson / Mikaela Glader / Muddathir S. Alhassan / Omer M. Abdalla / Richin John Koshy / Sadaf Kalsum / Thomas Schön / Waleed S. Koko

    Journal of ethnopharmacology. 2014 Nov. 18, v. 157

    2014  

    Abstract: The emergence of multidrug-resistant strains of Mycobacterium tuberculosis underscores the need for continuous development of new and efficient methods to determine the susceptibility of isolates of Mycobacterium tuberculosis in the search for novel ... ...

    Abstract The emergence of multidrug-resistant strains of Mycobacterium tuberculosis underscores the need for continuous development of new and efficient methods to determine the susceptibility of isolates of Mycobacterium tuberculosis in the search for novel antimycobacterial agents. Natural products constitute an important source of new drugs, and design and implementation of antimycobacterial susceptibility testing methods are necessary to evaluate the different extracts and compounds. In this study we have explored the antimycobacterial properties of 50 ethanolic extracts from different parts of 46 selected medicinal plants traditionally used in Sudan to treat infectious diseases.Plants were harvested and ethanolic extracts were prepared. For selected extracts, fractionation with hydrophilic and hydrophobic solvents was undertaken. A luminometry-based assay was used for determination of mycobacterial growth in broth cultures and inside primary human macrophages in the presence or absence of plant extracts and fractions of extracts. Cytotoxicity was also assessed for active fractions of plant extracts.Of the tested extracts, three exhibited a significant inhibitory effect on an avirulent strain of Mycobacterium tubercluosis (H37Ra) at the initial screening doses (125 and 6.25μg/ml). These were bark and leaf extracts of Khaya senegalensis and the leaf extract of Rosmarinus officinalis L. Further fractions of these plant extracts were prepared with n-hexane, chloroform, ethyl acetate, n-butanol, ethanol and water, and the activity of these extracts was retained in hydrophobic fractions. Cytotoxicity assays revealed that the chloroform fraction of Khaya senegalensis bark was non-toxic to human monocyte-derived macrophages and other cell types at the concentrations used and hence, further analysis, including assessment of IC50 and intracellular activity was done with this fraction.These results encourage further investigations to identify the active compound(s) within the chloroform fraction of Khaya senegalensis bark.
    Keywords active ingredients ; antibacterial properties ; antibiotics ; avirulent strains ; bark ; butanol ; chloroform ; culture media ; cytotoxicity ; ethanol ; ethyl acetate ; fractionation ; hexane ; hydrophilicity ; hydrophobicity ; infectious diseases ; inhibitory concentration 50 ; Khaya senegalensis ; leaf extracts ; macrophages ; medicinal plants ; multiple drug resistance ; Mycobacterium tuberculosis ; new drugs ; Rosmarinus officinalis ; screening ; solvents ; traditional medicine ; Sudan
    Language English
    Dates of publication 2014-1118
    Size p. 134-139.
    Publishing place Elsevier Ireland Ltd
    Document type Article
    ZDB-ID 134511-4
    ISSN 1872-7573 ; 0378-8741
    ISSN (online) 1872-7573
    ISSN 0378-8741
    DOI 10.1016/j.jep.2014.09.020
    Database NAL-Catalogue (AGRICOLA)

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