| 1. |
|
|
| 2. |
- Katsivalis, Ioannis, 1986, et al.
(författare)
-
Strength analysis and failure prediction of thin tow-based discontinuous composites
- 2024
-
Ingår i: Composites Science And Technology. - : Elsevier BV. - 0266-3538 .- 1879-1050. ; 245
-
Tidskriftsartikel (refereegranskat)abstract
- Tow Based Discontinuous Composites (TBDCs) are a new class of composite materials which combine in-plane isotropy, high strength and stiffness and enhanced manufacturability. However, due to their complicated micro-architecture, characterising the performance of these materials and predicting their response is challenging. This work develops a complete experimental and analytical framework which identifies all the key properties in the performance of the TBDCs, characterises them experimentally and builds an analytical predictive tool for both the stiffness response and the strength of the TBDC material. Fractography is also utilised to identify the damage mechanisms and correlate them with the analytical predictions. A parametric study is developed which shows the critical effect that the tape thickness and mode II fracture toughness have on the TBDCs. Finally, the performance of the material is compared to similarly developed TBDCs from the literature and shows the significant strength and stiffness increases recorded through the combination of the thin high-modulus tapes and the increased fibre volume fractions.
|
|
| 3. |
- Lannergård, Jonas, et al.
(författare)
-
Sequence variability is correlated with weak immunogenicity in Streptococcus pyogenes M protein.
- 2015
-
Ingår i: MicrobiologyOpen. - : Wiley. - 2045-8827. ; 4:5, s. 774-789
-
Tidskriftsartikel (refereegranskat)abstract
- The M protein of Streptococcus pyogenes, a major bacterial virulence factor, has an amino-terminal hypervariable region (HVR) that is a target for type-specific protective antibodies. Intriguingly, the HVR elicits a weak antibody response, indicating that it escapes host immunity by two mechanisms, sequence variability and weak immunogenicity. However, the properties influencing the immunogenicity of regions in an M protein remain poorly understood. Here, we studied the antibody response to different regions of the classical M1 and M5 proteins, in which not only the HVR but also the adjacent fibrinogen-binding B repeat region exhibits extensive sequence divergence. Analysis of antisera from S. pyogenes-infected patients, infected mice, and immunized mice showed that both the HVR and the B repeat region elicited weak antibody responses, while the conserved carboxy-terminal part was immunodominant. Thus, we identified a correlation between sequence variability and weak immunogenicity for M protein regions. A potential explanation for the weak immunogenicity was provided by the demonstration that protease digestion selectively eliminated the HVR-B part from whole M protein-expressing bacteria. These data support a coherent model, in which the entire variable HVR-B part evades antibody attack, not only by sequence variability but also by weak immunogenicity resulting from protease attack.
|
|
| 4. |
- Lannergård, Jonas, et al.
(författare)
-
The Hypervariable Region of Streptococcus pyogenes M Protein Escapes Antibody Attack by Antigenic Variation and Weak Immunogenicity.
- 2011
-
Ingår i: Cell Host and Microbe. - : Elsevier BV. - 1934-6069 .- 1931-3128. ; 10:2, s. 147-157
-
Tidskriftsartikel (refereegranskat)abstract
- Sequence variation of antigenic proteins allows pathogens to evade antibody attack. The variable protein commonly includes a hypervariable region (HVR), which represents a key target for antibodies and is therefore predicted to be immunodominant. To understand the mechanism(s) of antibody evasion, we analyzed the clinically important HVR-containing M proteins of the human pathogen Streptococcus pyogenes. Antibodies elicited by M proteins were directed almost exclusively against the C-terminal part and not against the N-terminal HVR. Similar results were obtained for mice and humans with invasive S. pyogenes infection. Nevertheless, only anti-HVR antibodies protected efficiently against infection, as shown by passive immunizations. The HVR fused to an unrelated protein elicited no antibodies, implying that it is inherently weakly immunogenic. These data indicate that the M protein HVR evades antibody attack not only through antigenic variation but also by weak immunogenicity, a paradoxical observation that may apply to other HVR-containing proteins.
|
|
| 5. |
- Ljungvall, Karl, et al.
(författare)
-
Heavy metal concentrations in female wild mink (Neovison vison) in Sweden : Sources of variation and associations with internal organ weights
- 2017
-
Ingår i: Environmental Toxicology and Chemistry. - : Wiley. - 0730-7268 .- 1552-8618. ; 36:8, s. 2030-2035
-
Tidskriftsartikel (refereegranskat)abstract
- The American mink is an invasive species in Sweden, and it is legally hunted all year. Therefore, the mink is well suited as a sentinel species for environmental monitoring. In the present study female mink (n = 91) from 6 different areas in Sweden were analyzed for the concentrations of silver, cadmium, mercury and lead in liver tissue using inductively coupled plasma mass spectrometry. The wet concentrations in liver tissue were 42.6 +/- 52.7 ng/g for silver, 99.5 +/- 100 ng/g for cadmium, 652 +/- 537 ng/g formercury, and 196 +/- 401 ng/g for lead (expressed as mean + standard deviation). There were associations between the sample area and the concentrations of silver, lead, and mercury. The concentrations of lead and cadmium varied with season of capture and lead, cadmium, and mercury were positively associated with increasing age. Relative liver weight was positively associated with concentrations of mercury and negatively associated with lead and cadmium. Relative kidney weight was negatively associated with lead concentrations. In summary, it is of importance to take age and season of capture into account when assessing levels of heavy metals in wild mink. Also, liver and kidneys seem to be potential targets for heavy metal toxicity in wild female mink in Sweden.
|
|
| 6. |
|
|
| 7. |
- Madej, Malgorzata, et al.
(författare)
-
The Effect of Boar Seminal Plasma on the Release of Prostaglandins and Interleukin-6 by Porcine Endometrial and Cervical Cells and Bovine Endometrial Cells
- 2012
-
Ingår i: Reproduction in Domestic Animals. - : Wiley. - 0936-6768 .- 1439-0531. ; 47, s. 113-124
-
Tidskriftsartikel (refereegranskat)abstract
- Artificial insemination (AI) of sows results in a significant elevation of prostaglandin F2a metabolite (PGFM) levels in peripheral plasma, whereas in mated sows such elevation is not seen. The aim of this study was to investigate whether boar seminal plasma (SP) has any effect on the release of PGFM, prostaglandin F2a (PGF2a), prostaglandin E2 (PGE2) or interleukin-6 (IL-6) by in vitro cultured porcine endometrial (epithelial pUE and stromal pUS), cervical (pCE and pCS) and bovine endometrial epithelial cells (bUE). This study shows that boar SP inhibits the release of PGFM, PGF2a and PGE2 by porcine endometrial and cervical cells and bovine endometrial cells after 3 and 24 h incubation. Boar SP stimulated IL-6 release by pUE, pUS and even bUE after 3 h incubation. Tumour necrosis factor a (TNFa) stimulated the release of IL-6 by pUS only after 24 h incubation, but in the presence of boar SP, this stimulation was attenuated. The overall results from these in vitro studies give us possibility to understand the difference in prostaglandin response between mated and inseminated sows. Furthermore, we demonstrated that frozen-stored epithelial and stromal cells from pig endometrium, as well as from the cervix are suitable for studying the effect of SP on the release of prostaglandins. The only prerequisite is to incubate these thawed cells with arachidonic acid as a source for the synthesis of prostaglandins. A similar effect of boar SP on porcine and bUE cells may suggest inter-species reactivity.
|
|
| 8. |
- Movert, Elin, et al.
(författare)
-
Interplay between human STING genotype and bacterial NADase activity regulates inter-individual disease variability
- 2023
-
Ingår i: Nature Communications. - 2041-1723. ; 14:1
-
Tidskriftsartikel (refereegranskat)abstract
- Variability in disease severity caused by a microbial pathogen is impacted by each infection representing a unique combination of host and pathogen genomes. Here, we show that the outcome of invasive Streptococcus pyogenes infection is regulated by an interplay between human STING genotype and bacterial NADase activity. S. pyogenes-derived c-di-AMP diffuses via streptolysin O pores into macrophages where it activates STING and the ensuing type I IFN response. However, the enzymatic activity of the NADase variants expressed by invasive strains suppresses STING-mediated type I IFN production. Analysis of patients with necrotizing S. pyogenes soft tissue infection indicates that a STING genotype associated with reduced c-di-AMP-binding capacity combined with high bacterial NADase activity promotes a ‘perfect storm’ manifested in poor outcome, whereas proficient and uninhibited STING-mediated type I IFN production correlates with protection against host-detrimental inflammation. These results reveal an immune-regulating function for bacterial NADase and provide insight regarding the host-pathogen genotype interplay underlying invasive infection and interindividual disease variability.
|
|
| 9. |
- Norrby, Mattias, et al.
(författare)
-
Effects of genistein on oestrogen and progesterone receptor, proliferative marker Ki-67 and carbonic anhydrase localisation in the uterus and cervix of gilts after insemination
- 2013
-
Ingår i: Animal Reproduction Science. - : Elsevier BV. - 0378-4320 .- 1873-2232. ; 138, s. 90-101
-
Tidskriftsartikel (refereegranskat)abstract
- Soya products are routinely fed to domestic animals as an important source of protein. The aim of this work was to study how the phytooestrogen genistein, supplemented at a feed relevant level, affects the morphology and distribution of reproductive hormone receptors, proliferative activities and carbonic anhydrase (CA) in the uterus and cervix of gilts. Eleven gilts were fed a soya-free diet. Six were given genistein (1 mg/kg bw) twice daily for eight days starting three days before expected oestrus. Five gilts were used as controls. All gilts were inseminated (AI) one day after signs of standing oestrus and euthanized three days after AI. Samples from the uterus and cervix were processed for morphometric evaluation, immunohistochemical localisation of oestrogen receptors alpha and beta (ER alpha and ER beta), progesterone receptor (PR), proliferative marker Ki-67 and histochemical localisation of CA. Nuclear staining for ER beta was detected in surface epithelial, glandular and some stromal cells in the uterus and in the cervix surface epithelial cells. ER alpha and PR were observed in surface epithelium, subepithelial stromal cells and smooth muscle cells of uterus and cervix, and glandular cells of the uterus. Ki-67 positive cells were recorded in uterine and cervical surface epithelium and subepithelial stromal layer. CA was mainly confined to glandular cells of the uterus. Immunohistochemical results were evaluated using semi-quantitative image analysis. Statistic comparison between groups revealed no differences. However, intra-treatment evaluation and correlations indicate that the supplementation of genistein modulates the expression pattern of all receptors and Ki-67, which may induce cellular activities in both the uterus and cervix of early pregnant gilts. (C) 2013 Elsevier B.V. All rights reserved.
|
|
| 10. |
|
|
