| 1. |
- Akrami, Nazar, et al.
(författare)
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Classical and modern prejudice : attitudes toward people with intellectual disabilities.
- 2006
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Ingår i: Research in Developmental Disabilities. - : Elsevier BV. - 0891-4222 .- 1873-3379. ; 27:6, s. 605-617
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Tidskriftsartikel (refereegranskat)abstract
- In two studies, we examine whether attitudes toward people with intellectual disabilities, like sexism and racism, consist of two forms – a classical and a modern, where the classical is overt and blatant and the modern is more subtle and covert. Self-report scales tapping these two forms were developed in Study 1. Based on confirmatory factor analyses, the results in Study 1 supported our hypothesis and revealed that the modern and classical forms are correlated but distinguishable. This outcome was replicated in Study 2. Construct and discriminatory validations of the scales provided further support for the distinction. The theoretical and practical importance of the results is discussed in relation to previous research on attitudes toward people with intellectual disabilities and other social outgroups.
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| 2. |
- Albert, Malin, et al.
(författare)
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Aetiology and outcome in hospitalized cardiac arrest patients.
- 2023
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Ingår i: European Heart Journal Open. - 2752-4191. ; 3:4
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Tidskriftsartikel (refereegranskat)abstract
- AIMS: To study aetiologies of in-hospital cardiac arrests (IHCAs) and their association with 30-day survival.METHODS AND RESULTS: Observational study with data from national registries. Specific aetiologies (n = 22) of IHCA patients between April 2018 and December 2020 were categorized into cardiac vs. non-cardiac and six main aetiology categories: myocardial ischemia, other cardiac causes, pulmonary causes, infection, haemorrhage, and other non-cardiac causes. Main endpoints were proportions in each aetiology, 30-day survival, and favourable neurological outcome (Cerebral Performance Category scale 1-2) at discharge. Among, 4320 included IHCA patients (median age 74 years, 63.1% were men), approximate 50% had cardiac causes with a 30-day survival of 48.4% compared to 18.7% among non-cardiac causes (P < 0.001). The proportion in each category were: myocardial ischemia 29.9%, pulmonary 21.4%, other cardiac causes 19.6%, other non-cardiac causes 11.6%, infection 9%, and haemorrhage 8.5%. The odds ratio (OR) for 30-day survival compared to myocardial ischemia for each category were: other cardiac causes OR 1.48 (CI 1.24-1.76); pulmonary causes OR 0.36 (CI 0.3-0.44); infection OR 0.25 (CI 0.18-0.33); haemorrhage OR 0.22 (CI 0.16-0.3); and other non-cardiac causes OR 0.56 (CI 0.45-0.69). IHCA caused by myocardial ischemia had the best favourable neurological outcome while those caused by infection had the lowest OR 0.06 (CI 0.03-0.13).CONCLUSION: In this nationwide observational study, aetiologies with cardiac and non-cardiac causes of IHCA were evenly distributed. IHCA caused by myocardial ischemia and other cardiac causes had the strongest associations with 30-day survival and neurological outcome.
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| 3. |
- Albert, Malin, et al.
(författare)
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Cardiac arrest after pulmonary aspiration in hospitalised patients : a national observational study.
- 2020
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Ingår i: BMJ Open. - : BMJ. - 2044-6055. ; 10:3
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: To study characteristics and outcomes among patients with in-hospital cardiac arrest (IHCA) due to pulmonary aspiration.DESIGN: A retrospective observational study based on data from the Swedish Registry of Cardiopulmonary Resuscitation (SRCR).SETTING: The SRCR is a nationwide quality registry that covers 96% of all Swedish hospitals. Participating hospitals vary in size from secondary hospitals to university hospitals.PARTICIPANTS: The study included patients registered in the SRCR in the period 2008 to 2017. We compared patients with IHCA caused by pulmonary aspiration (n=127), to those with IHCA caused by respiratory failure of other causes (n=2197).PRIMARY AND SECONDARY OUTCOME MEASURES: Primary outcome was 30-day survival. Secondary outcome was sustained return of spontaneous circulation (ROSC) defined as ROSC at the scene and admitted alive to the intensive care unit.RESULTS: In the aspiration group 80% of IHCA occurred on general wards, as compared with 63.6% in the respiratory failure group (p<0.001). Patients in the aspiration group were less likely to be monitored at the time of the arrest (18.5% vs 38%, p<0.001) and had a significantly lower rate of sustained ROSC (36.5% vs 51.6%, p=0.001). The unadjusted 30-day survival rate compared with the respiratory failure group was 7.9% versus 18.0%, p=0.024. In a propensity score analysis (including variables; year, age, gender, location of arrest, initial heart rhythm, ECG monitoring, witnessed collapse and a previous medical history of; cancer, myocardial infarction or heart failure) the OR for 30-day survival was 0.46 (95% CI 0.19 to 0.94).CONCLUSIONS: In-hospital cardiac arrest preceded by pulmonary aspiration occurred more often on general wards among unmonitored patients. These patients had a lower 30-day survival rate compared with IHCA caused by respiratory failure of other causes.
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| 4. |
- Bergman Ärlebäck, Jonas, 1972-, et al.
(författare)
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IPAs - ihopparningsaktiviteter : aktiviteter med låg tröskel som tränar elevers begrepps-, procedur-/ metod- och resonemangsförmåga
- 2017
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Syftet med denna rapport är att på ett beskrivande sätt delge hur arbetet i projektet om IPAs som genomförts HT2014 – VT2015 gått till och vilka erfarenheter och slutsatser som arbetet resulterat i. Den tänkte läsaren är framför allt kommunernas matematiklärare, men vi tror även att andra lärare och skolpersonal kan finna innehållet intressant och användbart. Det är vår förhoppning att rapporten med tillhörande aktiviteter kan inspirera till reflektion och en mer varierad undervisning. När pronomen som vi och oss används i rapporten åsyftats alla som aktivt ingått i IPAprojektets forskande grupp, vilken har bestått av såväl deltagande lärare som forskare:Marcus Claesson (Kungsgårdsgymnasiet, Norrköping), Malin Hällgren (Birgittaskolans vuxenutbildning, Linköping), Sofia Lindh (Hagagymnasiet, Norrköping), Mia Lundell (Djäkneparksskolan, Norrköping), Mattias Nordling (Anders Ljungstedska gymnasiet, Linköping) och Jonas Bergman Ärlebäck (LiU). Huvudansvaret för författandet av rapporten har Jonas haft som medverkande forskare i projektet. De medforskande lärarna har bidragit med analyser, erfarenheter och exempel från sina klassrum, utvecklat, testat och formulerat aktiviteterna som utgjort navet i projektet, samt läst och kommenterat rapporten under dess framställning.Rapporten följer samma logik och uppbyggnad som de rapporter skrivna inom det övergripande samarbetsprojektet Matematikdidaktik för bättre matematikkunskaper av det arbete och den forskning som bedrivits av Lisa Björklund Boistrup (Björklund Boistrup et al. 2013a; 2013b; 2013c; 2014a; 2014b). Vissa delar av texten använder därför, eller bygger till viss del på, Lisas texter, och när så är fallet tydliggörs detta med fotnoter. Andra delar av texten, så som exempelvis beskrivningen av de teoretiska utgångspunkterna, är i stort identiskt i samtliga delprojektsrapporter för de projekt som Jonas medverkat i som forskare (Ärlebäck et. al. 2017a, 2017b, 2017c, 2017d). Rapporten är dock skriven för att kunna läsas helt fristående från de andra rapporterna författade i projektet och förutsätter med andra ord ingen tidigare kunskap eller kännedom om projektet och de perspektiv som används. De läsare som redan tagit del av arbetet inom samarbetsprojektet Matematikdidaktik för bättre matematikkunskaper på olika sätt kommer här och var att känna igen sig, men vi hoppas att de delar som är unikt specifika för just detta delprojekt ska vara intressant och inspirerande.
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| 5. |
- Claesson, Ing-Marie, et al.
(författare)
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Pregnant womens intention to breastfeed; their estimated extent and duration of the forthcoming breastfeeding in relation to the actual breastfeeding in the first year postpartum-A Swedish cohort study
- 2019
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Ingår i: Midwifery. - : ELSEVIER SCI LTD. - 0266-6138 .- 1532-3099. ; 76, s. 102-109
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Tidskriftsartikel (refereegranskat)abstract
- Objectives: To investigate the prenatal intention to breastfeed and the estimated extent and duration of the forthcoming breastfeeding among nulliparous and multiparous women in different Body Mass Index (BMI) classes. Furthermore, in a sub-group we study the actual breastfeeding in relation to the prenatal intended extent and duration. Design: A prospective cohort study. Methods: A total of 775 pregnant women answered a questionnaire concerning their intention to breastfeed and how they estimated the extent and duration of the forthcoming breastfeeding. In a sub-group of 174 women, data from the actual breastfeeding were obtained. Findings: There was no difference concerning intention to breastfeed among underweight and normal weight women, overweight or obese nulliparous or multiparous women. Fewer multiparous women with BMI amp;lt;25 judged that the forthcoming breastfeeding would be partial, compared to multiparous women with overweight and obesity (p = 0.003). Furthermore, there was a significant difference within the group of nulliparous women concerning the prenatal intended extent and the actual breastfeeding at two weeks and five months postnatally (p = 0.000 and p = 0.041). There were more underweight and normal weight and overweight women who breastfed exclusively two weeks postnatally, compared with obese women. Additional, at five months postnatally there were more obese women who had ceased to breastfeed, than underweight and normal weight women. Conclusions: Among pregnant multiparous women there were more overweight and obese women who judged that the forthcoming breastfeeding would be partial, than pregnant underweight and normal weight women. The prenatal estimated extent of the forthcoming breastfeeding differed from the actually extent of breastfeeding among nulliparous women. Implications for practice: The antenatal breastfeeding information and education should be tailored to prepare every woman/couple, irrespective of maternal body composition for the forthcoming task and furthermore, the continuum of care, from antenatal care to Child Health Service should offer a supportive atmosphere to protect and promote breastfeeding (C) 2019 Elsevier Ltd. All rights reserved.
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| 6. |
- Claesson, Ing-Marie, et al.
(författare)
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The Association Between Covariates, with Emphasis on Maternal Body Mass Index, and Duration of Exclusive and Total Breastfeeding
- 2020
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Ingår i: Breastfeeding Medicine. - : MARY ANN LIEBERT, INC. - 1556-8253 .- 1556-8342. ; 15:10, s. 622-629
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Tidskriftsartikel (refereegranskat)abstract
- Objective:The aim of this study was to evaluate the association between possible covariates, with emphasis on maternal body mass index (BMI), on exclusive breastfeeding and on total breastfeeding during the first postnatal year. Design:A longitudinal study encompassing 723 women who were followed during the first postnatal year Methods:Data concerning pregnancy, delivery, neonatal period, and breastfeeding were extracted from respective medical records. Sociodemographic data on the participants were self-reported. The Cox Proportional Hazard Model was used for investigating the effects of different covariates. Results:Compared with women with BMI <25.0, obese women ran a higher risk of ceasing exclusive breastfeeding prematurely (Hazard ratio [HR] = 1.38,p = 0.009). Multiparous women had a lower risk of ceasing the exclusive breastfeeding prematurely, than primiparous women (HR = 0.78,p = 0.009). Concerning exclusive breastfeeding as well as total breastfeeding, the risk of prematurely ceasing the breastfeeding decreased with increasing age (p = 0.028 andp <= 0.001, respectively). Median duration of exclusive breastfeeding was shorter among obese women compared with women with BMI <30.0 (3.0 months versus 6.0 months). Corresponding figures for total breastfeeding were 4.0 months versus 8.0 months. Concerning parity and exclusive breastfeeding, there was no difference in median duration between primiparous women and multiparous women (4.0 months), whereas multiparous women had a longer median duration of total breastfeeding, than primiparous women (8.0 months versus 7.0 months). Conclusion:The risk of ceasing exclusive breastfeeding prematurely is high among obese women. This result indicates the need for targeted supportive interventions, individualized according to BMI. With increasing age, the risk of ceasing breastfeeding prematurely decreases, and compared with primiparous women, multiparous women run a lower risk of ceasing exclusive breastfeeding prematurely.
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| 7. |
- Claesson, Rolf, et al.
(författare)
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Actinomyces radicidentis and Actinomyces haliotis, coccoid Actinomyces species isolated from the human oral cavity
- 2017
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Ingår i: Anaerobe. - : Elsevier. - 1075-9964 .- 1095-8274. ; 48, s. 19-26
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Tidskriftsartikel (refereegranskat)abstract
- There are few reports on the bacterial species Actinomyces radicidentis in the literature. In this study, putative A. radicidentis isolates were collected from 16 root canal samples from 601 examined patients. The isolates were examined by biochemical tests, 16S rRNA gene sequencing, Arbitrarily-primed (AP-) PCR, antibiotic susceptibility testing, and MALDI-TOF analyses. In parallel, two A. radicidentis reference strains and two putative A. radicidentis isolates from United Kingdom were tested. Sixteen of the 18 isolates were confirmed as A. radicidentis. The remaining two isolates, both of which were isolated from root canals (one from Sweden and the other from the UK), but were identified as Actinomyces haliotis by sequencing ∼ 1300 base pairs of the 16S rRNA-gene. This isolates had a divergent, but between them similar, AP-PCR pattern, and a common distribution of sequence signatures in the 16S rRNA gene, but were not identified by MALDI-TOF. A. haliotis is a close relative to A. radicidentis, hitherto only been described from a sea-snail. The identity of A. haliotis was confirmed by a phylogenetic tree based on 16S rRNA gene sequences with species specific sequences included, and by additional biochemical tests. The examined bacteria exhibited similar antibiotic susceptibility patterns when tested for 10 separate antibiotic classes with E-tests (bioMérieux). The MIC90 for β-lactams (benzylpenicillin and cefuroxime) and vancomycin was 0.5 mg/L, for colistin and ciprofloxacin 8 mg/mL and for the other antibiotic classes ≤ 25 mg/mL The isolation of A. haliotis from infected dental root canals cast doubt on the accepted opinion that all Actinomyces infections have an endogenous source.
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| 8. |
- Gulliksson, Magdalena, et al.
(författare)
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Expression of 15-lipoxygenase type-1 in human mast cells
- 2007
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Ingår i: Biochimica et Biophysica Acta. - : Elsevier BV. - 0006-3002 .- 1878-2434. ; 1771:9, s. 1156-65
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Tidskriftsartikel (refereegranskat)abstract
- Mast cells play a key role in the pathophysiology of asthma. These cells exert their effector functions by releasing a variety of proinflammatory and immunoregulatory compounds. Mast cells infiltrate the bronchial epithelium and smooth muscle to a higher degree in patients with asthma compared to control subjects. 15-Lipoxygenase type-1 (15-LO-1) is a prooxidant enzyme which is expressed in asthmatic lungs leading to formation of pro- and anti-inflammatory mediators. Here we report that interleukin-4 (IL-4) induced the expression of 15-LO-1 in human cord blood derived mast cells (CBMC) as demonstrated by RT-PCR, western blot and immunocytochemistry. The major metabolite of arachidonic acid formed via the 15-LO pathway in IL-4 treated CBMC was identified as 15-ketoeicosatetraenoic acid (15-KETE, also named 15-oxo-ETE) with smaller amounts of 15-hydroxyeicosatetraenoic acid (15-HETE) as identified by HPLC and mass spectrometry (MS/MS). Furthermore, immunohistochemical stainings demonstrated the expression of 15-LO-1 in mast cells in lung and skin in vivo. Osmotic activation of CBMC with mannitol resulted in activation of the 15-LO-1 pathway. In conclusion, the expression of 15-LO-1 and release of 15-LO-1 derived products by mast cells may contribute to the role of these cells in asthma and other inflammatory diseases.
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| 9. |
- Larsson, Niklas, et al.
(författare)
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Plasma and bronchoalveolar lavage fluid oxylipin levels in experimental porcine lung injury
- 2022
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Ingår i: Prostaglandins & other lipid mediators. - : Elsevier. - 1098-8823 .- 2212-196X. ; 160
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Tidskriftsartikel (refereegranskat)abstract
- Inflammatory signaling pathways involving eicosanoids and other regulatory lipid mediators are a subject of intensive study, and a role for these in acute lung injury is not yet well understood. We hypothesized that oxylipin release from lung injury could be detected in bronchoalveolar lavage fluid and in plasma. In a porcine model of surfactant depletion, ventilation with hyperinflation was assessed. Bronchoalveolar lavage and plasma samples were analyzed for 37 different fatty acid metabolites (oxylipins). Over time, hyperinflation altered concentrations of 4 oxylipins in plasma (TXB2, PGE2, 15-HETE and 11-HETE), and 9 oxylipins in bronchoalveolar lavage fluid (PGF2α, PGE2, PGD2, 12,13-DiHOME, 11,12-DiHETrE, 13-HODE, 9-HODE, 15-HETE, 11-HETE). Acute lung injury caused by high tidal volume ventilation in this porcine model was associated with rapid changes in some elements of the oxylipin profile, detectable in lavage fluid, and plasma. These oxylipins may be relevant in the pathogenesis of acute lung injury by hyperinflation.
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| 10. |
- Li, Xiujuan, et al.
(författare)
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Suppressed Vascular Leakage and Myocardial Edema Improve Outcome From Myocardial Infarction
- 2020
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Ingår i: Frontiers in Physiology. - : Frontiers Media SA. - 1664-042X. ; 11
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Tidskriftsartikel (refereegranskat)abstract
- Aim: The acute phase of myocardial infarction (MI) is accompanied by edema contributing to tissue damage and disease outcome. Here, we aimed to identify the mechanism whereby vascular endothelial growth factor (VEGF)-A induces myocardial edema in the acute phase of MI to eventually promote development of therapeutics to specifically suppress VEGFA-regulated vascular permeability while preserving collateral vessel formation.Methods and Results: VEGFA regulates vascular permeability and edema by activation of VEGF receptor-2 (VEGFR2), leading to induction of several signaling pathways including the cytoplasmic tyrosine kinase c-Src. The activated c-Src in turn phosphorylates vascular endothelial (VE)-cadherin, leading to dissociation of endothelial adherens junctions. A particular tyrosine at position 949 in mouse VEGFR2 has been shown to be required for activation of c-Src. Wild-type mice and mice with phenylalanine replacing tyrosine (Y) 949 in VEGFR2 (Vegfr2Y949F/Y949F) were challenged with MI through permanent ligation of the left anterior descending coronary artery. The infarct size was similar in wild-type and mutant mice, but left ventricular wall edema and fibrinogen deposition, indicative of vascular leakage, were reduced in the Vegfr2Y949F/Y949F strain. When challenged with large infarcts, the Vegfr2Y949F/Y949F mice survived significantly better than the wild-type strain. Moreover, neutrophil infiltration and levels of myeloperoxidase were low in the infarcted Vegfr2Y949F/Y949F hearts, correlating with improved survival. In vivo tyrosine phosphorylation of VE-cadherin at Y685, implicated in regulation of vascular permeability, was induced by circulating VEGFA in the wild-type but remained at baseline levels in the Vegfr2Y949F/Y949F hearts.Conclusion: Suppression of VEGFA/VEGFR2-regulated vascular permeability leads to diminished edema without affecting vascular density correlating with improved myocardial parameters and survival after MI.
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| 11. |
- Lind, Jacob, et al.
(författare)
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Jakt på papperslösa gör oss till en polisstat
- 2016
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Ingår i: Svenska Dagbladet. - : Svenska Dagbladet. - 1101-2412. ; :2016-10-04
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Tidskriftsartikel (populärvet., debatt m.m.)abstract
- Regeringen föreslår nio åtgärder för att hitta och utvisa papperslösa. Det kommer att slå hårt och främst gå ut över redan svaga och jagade människor. Vi uppmanar därför regeringen att ta tillbaka åtgärderna, skriver 43 forskare.
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| 12. |
- Morin, Eric, et al.
(författare)
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VEGF receptor-2/neuropilin 1 trans-complex formation between endothelial and tumor cells is an independent predictor of pancreatic cancer survival
- 2018
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Ingår i: Journal of Pathology. - : John Wiley & Sons. - 0022-3417 .- 1096-9896. ; 246:3, s. 311-322
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Tidskriftsartikel (refereegranskat)abstract
- Unstable and dysfunctional tumor vasculature promotes cancer progression and spread. Signal transduction by the pro-angiogenic vascular endothelial growth factor (VEGF) receptor-2 (VEGFR2) is modulated by VEGFA-dependent complex formation with neuropilin 1 (NRP1). NRP1 expressed on tumor cells can form VEGFR2/NRP1 trans-complexes between tumor cells and endothelial cells which arrests VEGFR2 on the endothelial surface, thus interfering with productive VEGFR2 signaling. In mouse fibrosarcoma, VEGFR2/NRP1 trans-complexes correlated with reduced tumor vessel branching and reduced tumor cell proliferation. Pancreatic ductal adenocarcinoma (PDAC) strongly expressed NRP1 on both tumor cells and endothelial cells, in contrast to other common cancer forms. Using proximity ligation assay, VEGFR2/NRP1 trans-complexes were identified in human PDAC tumor tissue, and its presence was associated with reduced tumor vessel branching, reduced tumor cell proliferation, and improved patient survival after adjusting for other known survival predictors. We conclude that VEGFR2/NRP1 trans-complex formation is an independent predictor of PDAC patient survival.
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| 13. |
- Nilsson, Ingrid, et al.
(författare)
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VEGF receptor 2/-3 heterodimers detected in situ by proximity ligation on angiogenic sprouts
- 2010
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Ingår i: EMBO Journal. - : Wiley. - 0261-4189 .- 1460-2075. ; 29:8, s. 1377-1388
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Tidskriftsartikel (refereegranskat)abstract
- The vascular endothelial growth factors VEGFA and VEGFC are crucial regulators of vascular development. They exert their effects by dimerization and activation of the cognate receptors VEGFR2 and VEGFR3. Here, we have used in situ proximity ligation to detect receptor complexes in intact endothelial cells. We show that both VEGFA and VEGFC potently induce formation of VEGFR2/-3 heterodimers. Receptor heterodimers were found in both developing blood vessels and immature lymphatic structures in embryoid bodies. We present evidence that heterodimers frequently localize to tip cell filopodia. Interestingly, in the presence of VEGFC, heterodimers were enriched in the leading tip cells as compared with trailing stalk cells of growing sprouts. Neutralization of VEGFR3 to prevent heterodimer formation in response to VEGFA decreased the extent of angiogenic sprouting. We conclude that VEGFR2/-3 heterodimers on angiogenic sprouts induced by VEGFA or VEGFC may serve to positively regulate angiogenic sprouting.
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| 14. |
- Oscarsson, Jan, et al.
(författare)
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Phylogenetic Analysis of Filifactor alocis Strains Isolated from Several Oral Infections Identified a Novel RTX Toxin, FtxA
- 2020
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Ingår i: Toxins. - : MDPI. - 2072-6651. ; 12:11
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Tidskriftsartikel (refereegranskat)abstract
- Filifactor alocis is a Gram-positive asaccharolytic, obligate anaerobic rod of the phylum Firmicutes, and is considered an emerging pathogen in various oral infections, including periodontitis. We here aimed to perform phylogenetic analysis of a genome-sequenced F. alocis type strain (ATCC 35896; CCUG 47790), as well as nine clinical oral strains that we have independently isolated and sequenced, for identification and deeper characterization of novel genomic elements of virulence in this species. We identified that 60% of the strains carried a gene encoding a hitherto unrecognized member of the large repeats-in-toxins (RTX) family, which we have designated as FtxA. The clinical infection origin of the ftxA-positive isolates largely varied. However, according to MLST, a clear monophylogeny was reveled for all ftxA-positive strains, along with a high co-occurrence of lactate dehydrogenase (ldh)-positivity. Cloning and expression of ftxA in E. coli, and purification of soluble FtxA yielded a protein of the predicted molecular size of approximately 250 kDa. Additional functional and proteomics analyses using both the recombinant protein and the ftxA-positive, and -negative isolates may reveal a possible role and mechanism(s) of FtxA in the virulence properties of F.alocis, and whether the gene might be a candidate diagnostic marker for more virulent strains.
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| 15. |
- Sörensen, Malin Helena, 1979-
(författare)
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Mesostructured particulate silica materials with tunable pore size : Synthesis, characterization and applications
- 2009
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Colloidal assemblies of surfactants and polymers in aqueous solutions have been used by human mankind for hundreds of years and they are of great importance in many of our technological processes, such as fabrication of soap and papermaking. Less than two decades ago the idea of using colloidal assemblies as templates of inorganic materials was borne. A new population of materials, referred to as surfactant templated materials, took form. These materials showed extraordinary properties such as monodisperse pore size distribution, large surface areas and pore volumes. The main focus of this thesis has been on synthesis and functionalisation of spherical mesostructured silica particulate materials. In the first part of the work, mesostructured materials with expanded pores have been produced using a well established aerosol-based method as well as the newly developed emulsion and solvent evaporation (ESE) method. Increase in pore size was realized through using Pluronic block copolymer F127 together with a swelling agent poly(propylene glycol) as template. The influence of the swelling agent on pore size expansion was shown to have a roughly linear relationship. Furthermore, the impact of synthesis parameters on internal and exterior morphology has been investigated. Accessibility of the internal pore space, as well as the external surface roughness were shown to be highly dependent on synthesis temperature. Additionally, a very interesting well ordered 3D closed packed (P63/mmc) material was produced using the ionic surfactant C16TAB as template in the ESE method. In the second part of the thesis work, mesoporous spheres with large pore size, having either hydrophilic or hydrophobic surface properties, were used as carriers of an enzyme, lipase. The enzymatic activity of lipase was increased onto the hydrophobic surface, compared to lipase immobilized into the hydrophilic support as well as for lipase free in solution. This effect was probably due to a combination of enhanced hydrophobic interactions preventing denaturation of the enzyme and interfacial activation of the enzyme. This study generated an inorganic carrier material that is a promising candidate for biocatalysis applications. Additionally, mesoporous spheres were used as carriers of a model drug, Ibuprofen, to study the effect of polyelectrolyte multilayers on release properties. However, these layers were shown impermeable independent on pH and the substance was only released from uncoated particles.
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