SwePub
Sök i SwePub databas

  Utökad sökning

Träfflista för sökning "WFRF:(Nygren Erik) "

Sökning: WFRF:(Nygren Erik)

  • Resultat 1-50 av 74
Sortera/gruppera träfflistan
   
NumreringReferensOmslagsbildHitta
1.
  •  
2.
  •  
3.
  • Ekström, Mikael, et al. (författare)
  • Antiferromagnetism in Zn-doped La2CuO4 as observed by muon spin resonance spectroscopy
  • 2001
  • Ingår i: Physical Review B - Condensed Matter and Materials Physics. - 0163-1829. ; 64:18, s. 1845221-1845226
  • Tidskriftsartikel (refereegranskat)abstract
    • The local fields seen by positive muons implanted in Zn-doped La2CuO4 show a distribution with a main peak attributed to muon sites far from the Zn ions and a satellite structure corresponding to muons residing closer to the Zn. The temperature dependence indicates a strong loss of magnetic order for Cu moments near the Zn atoms. The data can be understood in terms of a model where a Zn ion not only introduces a vacancy in the magnetic Cu lattice but also creates a RKKY-type disturbance. The electron spin polarization around the Zn ions induces a change of the magnetic moments on surrounding Cu ions. The AF lattice is found to be strongly perturbed within a radius of 10 Angstrom around each Zn ion. Possible consequences for the superconductivity of the corresponding Sr-doped materials are discussed.
  •  
4.
  • Nygren, Andreas, 1967, et al. (författare)
  • Autoregulation of human jejunal mucosal perfusion during cardiopulmonary bypass.
  • 2006
  • Ingår i: Anesthesia and analgesia. - 1526-7598. ; 102:6, s. 1617-22
  • Tidskriftsartikel (refereegranskat)abstract
    • Animal studies have suggested that autoregulation of intestinal blood flow is severely impaired during cardiopulmonary bypass (CPB). We investigated the jejunal mucosal capacity to autoregulate perfusion during nonpulsatile CPB (34 degrees C) in 10 patients undergoing elective cardiac surgery. Changes in mean arterial blood pressure (MAP) were induced by altering the CPB flow rate randomly for periods of 3 min from 2.4 L/min/m2 to either 1.8 or 3.0 L/min/m2. Jejunal mucosal perfusion (JMP) was continuously recorded by laser Doppler flowmetry. A typical pattern of flow motion (vasomotion) was recorded in all patients during CPB. Variations in CPB flow rates caused no significant changes in mean JMP, jejunal mucosal hematocrit, or red blood cell velocity within a range of MAP from 50 +/- 15 to 74 +/- 16 mm Hg. The vasomotion frequency and amplitude was positively correlated with CPB flow rate. IV injections of prostacyclin (10 microg, Flolan) blunted vasomotion and increased JMP from 192 +/- 53 to 277 +/- 70 (P < 0.05) perfusion units despite a reduction in MAP from 59 +/- 12 to 45 +/- 10 mm Hg (P < 0.05). Prostacyclin-induced vasodilation resulted in loss of mucosal autoregulation (pressure-dependent perfusion). We conclude that autoregulation of intestinal mucosal perfusion is maintained during CPB in humans.
  •  
5.
  • Nygren, Karina, et al. (författare)
  • Adolescent self-reported health in relation to school factors : a multilevel analysis
  • 2014
  • Ingår i: Journal of School Nursing. - : Sage Publications. - 1059-8405 .- 1546-8364. ; 30:2, s. 114-122
  • Tidskriftsartikel (refereegranskat)abstract
    • The aim of the study was to examine school-related determinants of self-reported health among adolescents. Questionnaire survey data comprising 4,972 students, Grades 7 through 9, from 20 schools in northern Sweden were used. Also, complimentary data about each school were collected from the Swedish National Agency for Education. Using multilevel logistic regression analyses, results showed that most variation in self-reported health was explained by individual-level differences. Truancy, bullying, and poor relations with teachers significantly increased the odds ratio of reporting poor general health, for boys and for girls. Most variables at the school level, for example, school size and student-teacher ratio, did not render significant associations with students' self-reported health. In conclusion, this study indicates that health promotion at school, including school health services, may benefit from focusing primarily on individual-level determinants of health, that is, students' relations to peers and teachers, without ignoring that bullying and weak student-teacher relationships also may induce school-level interventions.
  •  
6.
  • Nygren, Karina, 1974-, et al. (författare)
  • Parents matter : but relations to parents do not explain gender differences in self-reported health in adolescents
  • 2012
  • Ingår i: Scandinavian Journal of Caring Sciences. - : Wiley. - 0283-9318 .- 1471-6712. ; 26:4, s. 643-653
  • Tidskriftsartikel (refereegranskat)abstract
    • The aim of the study was to explore whether parent-adolescent relations are associated to self-reported health of adolescents. Logistic regression analyses were performed on a cross-sectional data set consisting of 5060 adolescents, grades 7-9, from six municipalities in the northern part of Sweden. The study was approved by the Regional Ethical Review Board in Umeå, Sweden. Results showed that, in both boys and girls, experiencing low parental demands as well as perceiving the relationship quality and the communication with parents as poor were significantly associated with having poor general health, somatic complaints and feelings of stress. In general, girls scored lower on self-reported health than boys, but our findings indicate that these gender differences could not be explained by relations to parents. In conclusion, relations to parents play an important role for self-reported health of adolescents. Although no causal-effect statements can be determined in this study, it is implied that there is a need for health professionals, such as school nurses, school welfare officers, etc., to pay special attention to parent-adolescent relations in their work with adolescents.
  •  
7.
  • Thorén, Anders, 1955, et al. (författare)
  • Cardiopulmonary bypass in humans--jejunal mucosal perfusion increases in parallel with well-maintained microvascular hematocrit.
  • 2005
  • Ingår i: Acta anaesthesiologica Scandinavica. - : Wiley. - 0001-5172 .- 1399-6576. ; 49:4, s. 502-9
  • Tidskriftsartikel (refereegranskat)abstract
    • BACKGROUND: An imbalance between splanchnic oxygen supply and demand occurs during cardiopulmonary bypass (CPB) in man, which might disrupt the intestinal mucosal barrier function. The aim of the present study was to evaluate the effects of mild hypothermic CPB on intestinal mucosal perfusion in man undergoing cardiac surgery. Additionally we aimed to identify variables, which independently could predict changes of intestinal mucosal microcirculatory variables during CPB. METHODS: Jejunal mucosal perfusion (JMP), jejunal mucosal hematocrit (JMHt), red blood cell (RBC) velocity and arteriolar vasomotion using endoluminal jejunal laser Doppler flow metry were studied in eight cardiac surgical patients before and during CPB at a temperature of 34 degrees C. RESULTS: Cardiopulmonary bypass and the accompanied hemodilution (25-30%) induced a 44% increase in JMP (P < 0.05) and a 42% increase in RBC velocity (P < 0.01), with no change in JMHt. The oscillation amplitude of JMP, at a fundamental frequency of 2.8 cycles min(-1), increased with 175% (P < 0.05) during CPB. Splanchnic oxygen extraction increased by 64% during CPB (P < 0.05). Stepwise multiple regression analysis identified systemic hematocrit, arterial O2 and CO2 tension and splanchnic oxygen extraction as independent predictors of RBC velocity during CPB (R2=0.63, P < 0.001). The oscillation amplitude of JMP was predicted by RBC velocity and splanchnic oxygen extraction (R2= 0.68, P <0.0001). CONCLUSIONS: The increase in RBC velocity and enhanced arteriolar vasomotion, as well as maintained jejunal mucosal hematocrit, are microcirculatory, compensatory mechanisms for the splanchic oxygen supply/demand mismatch seen during cardiopulmonary bypass in humans.
  •  
8.
  •  
9.
  • Alsved, Malin, et al. (författare)
  • Droplet, aerosol and SARS-CoV-2 emissions during singing and talking
  • 2021
  • Konferensbidrag (refereegranskat)abstract
    • IntroductionAs the pandemic continues to spread, more knowledge is needed about the viral transmission routes. Several super spreading events during the Covid-19 pandemic have been linked to singing in choirs and talking loud. However, in the beginning of the pandemic there was only one study about emitted aerosols and droplets from singing, published in 1968, and only a handful on emissions from talking. Therefore, we conducted a study to measure the aerosol and droplet emissions from talking and singing. We also evaluated the emissions from singing when wearing a face mask.We have further developed our setup so that we collect the aerosol particles from Covid-19 infected patients that are talking and singing, and analyze our samples for SARS-CoV-2, the virus causing Covid-19.MethodTwelve healthy singers (7 professionals, 5 amateurs) were included in the first study part on quantifying the amount of emitted aerosols and droplets. The singers were singing or talking a short consonant rich text repeatedly at a constant pitch with their face in the opening of a funnel. The aerosol particle size and concentration was measured from the other end of the funnel using an aerodynamic particle sizer (APS, 3321, TSI Inc). In addition, the amount of un-evaporated droplets were captured with a high-speed camera and quantified using image analysis.During February and March 2021 we will collect aerosol particles from patients with confirmed Covid-19 that are singing and talking into a funnel. We will use a growth tube condensation collector, a BioSpot (Aerosol Devices), operating at 8 L min-1, and a NIOSH BC-251 cyclone sampler operating at 3.5 L min-1 (TISCH Environmental). The BioSpot collects the whole range of exhaled aerosol particles with high (95%) efficiency into liquid, and the NIOSH cyclone sampler collects particles into three size fractions: <1 µm (filter), 1-4 µm (liquid), >4 µm (liquid). The APS is again used to measure size and concentration of the emitted aerosol particles, so that emissions from infected test subjects can be compared with those of the healthy test subjects. Air samples will be analyzed for detection of SARS-CoV-2 genes, and if possible, SARS-CoV-2 infectivity in cell cultures.ResultsAerosol particle emissions from healthy test subjects were significantly higher during normal singing (median 690, range [320–2870] particles/s) than during normal talking (270 [120–1380] particles/s) (Wilcoxon’s signed rank test, p=0.002). Loud singing produced even more aerosol particles (980 [390–2870] particles/s) than normal singing (p=0.002). The amount of non-evaporated droplets detected by the high-speed camera setup showed similar results: more droplets during loud singing or talking. For both aerosol particle concentrations and droplet numbers, the levels were reduced by on average 70-80% when wearing a surgical face mask.ConclusionsSinging and talking give rise to high aerosol and droplet emissions from the respiratory tract. This is likely an important transmission route for Covid-19. In our upcoming part of the study we hope to determine how much SARS-CoV-2 that is emitted during these social activities.
  •  
10.
  • Bellner, Lars, 1973, et al. (författare)
  • A proinflammatory peptide from herpes simplex virus type 2 glycoprotein G affects neutrophil, monocyte, and NK cell functions
  • 2005
  • Ingår i: J Immunol. - : American Association of Immunologists. ; 174:4, s. 2235-2241
  • Tidskriftsartikel (refereegranskat)abstract
    • We have identified a synthetic peptide derived from the secreted portion of HSV type 2 glycoprotein G, denoted gG-2p20, which has proinflammatory properties in vitro. The gG-2p20 peptide, corresponding to aa 190-205 of glycoprotein G-2, was a chemoattractant for both monocytes and neutrophils in a dose-dependent fashion, and also induced the release of reactive oxygen from these cells. The receptor mediating the responses was identified as the formyl peptide receptor. The gG-2p20-induced activation of phagocytes had a profound impact on NK cell functions. The reactive oxygen species produced by gG-2p20-activated phagocytes both inhibited NK cell cytotoxicity and accelerated the apoptotic cell death in NK cell-enriched lymphocyte populations. Hence, we have for the first time been able to identify a potential function of the secreted portion of HSV-2 glycoprotein G. We propose that the proinflammatory gG-2p20 peptide identified could contribute to a reduced function and viability of NK cells during HSV-2 infection due to its ability to recruit and activate phagocytic cells.
  •  
11.
  • Berglund, Åke, et al. (författare)
  • An explorative randomised phase II study of sequential chemotherapy in advanced upper gastrointestinal cancer
  • 2010
  • Ingår i: Medical Oncology. - : Springer Science and Business Media LLC. - 1357-0560 .- 1559-131X. ; 27:1, s. 65-72
  • Tidskriftsartikel (refereegranskat)abstract
    • The feasibility, safety, and efficacy of planned sequential administration of docetaxel and irinotecan with 5-fluorouracil (5-FU)/leucovorin in advanced upper gastrointestinal adenocarcinoma (UGIA) are unknown. Seventy-three patients with gastric (GC; n = 22), pancreatic (PC; n = 28) or biliary cancer (BC; n = 23) were randomised to start with 45 mg/m2 docetaxel or 180 mg/m2 irinotecan combined with 5-FU/leucovorin every 2nd week. After every 2nd course, the patients were crossed over to the other combination. Treatment was given for a maximum of 12 courses. Quality-of-life (QoL) was evaluated during the first two months using the EORTC QLQ-C30. Eighteen patients (25%; GC 32%, PC 21%, BC 22%) demonstrated partial response (PR) and 21 (29%) had prolonged stable disease. Mean QoL scores were low at baseline. Twenty-three (32%) patients had improved QoL using a summary measure and 13 were stable. Median time to progression was 4.4 months and overall survival 8.2 months. The treatments were reasonably well tolerated. Grade 3–4 toxicities were slightly more common for the docetaxel combination. There were two treatment-related deaths. Planned sequential treatment with docetaxel or irinotecan with 5-FU/leucovorin is feasible, reasonably tolerable and appears active in advanced UGIA.
  •  
12.
  •  
13.
  • Bergstrand, Anna, et al. (författare)
  • Samverkansmeritering - förutsättningar, behov och möjligheter : Rapport: MERSAM-Meritvärde av samverkansskicklighet
  • 2021
  • Rapport (populärvet., debatt m.m.)abstract
    • Samverkansuppgiften har gradvis fått en tydligare roll sedan mitten av 1990-talet och är idag en nödvändig och central uppgift för högskolor och universitet i Sverige, inte minst för att hantera vår tids samhällsutmaningar. Det finns få tecken på att denna utveckling kommer att vända och det är därför viktigt att vi inom sektorn för en dialog kring hur vi tar oss an och värderar det arbete som sker inom ramen för samverkansuppgiften. Det är troligt att vi i sektorn även en tid framöver kommer att diskutera hur samverkansuppgiften bör tolkas och samverkansmeriter värderas, men det hindrar oss inte att på allvar försöka stödja och strukturera det arbete som redan sker dagligen vid landets lärosäten.Projektets bidrag är att belysa ett antal observationer kring utmaningar inom sektorn, för våra lärosäten och individer men också visa på möjligheter för våra lärosäten genom att ta upp några tänkbara verktyg, arbetssätt och rekommendationer för utveckling av samverkansmeritering.Huvudbudskapen i denna rapport är att sektorn behöver skapa en tydligare och mer preciserad begreppsbildning relaterat till ”samverkan” och samverkansmeriter. Lärosätena behöver utveckla ett mer integrerat och strukturerat sätt att arbeta med samverkansmeriter genom hela rekrytering- och befordringsprocessen, då förståelse av samverkansmeriter och praxis fortfarande är underutvecklat. Lärosätena behöver vidare utveckla stöd för forskare och lärare i att kunna sammanställa och dokumentera samverkansmeriter, separat eller integrerat med övriga meriter. En verkningsfull, flerspråkig begreppsapparat och förståelse men även efterfrågan på samverkansmeriter behöver utvecklas gemensamt av sektorns alla aktörer och vid varje lärosäte.Rapporten riktar sig i första hand till två målgrupper:1.Personer och funktioner vid lärosäten som har ansvar för eller leder utvecklingsarbete kopplat till meritering och kompetensförsörjning på olika nivåer (dekaner, utvecklingsledare, HR specialister, ordförande i rekryteringskommittéer eller motsvarande samt olika former av samverkansstöd). För dessa innehåller rapporten resonemang, rekommendationer och konkreta verktyg som kan användas som utgångspunkt för dialog och utveckling av samverkansmeritering vid lärosäten.2.Ledningsfunktioner vid lärosäten, myndigheter samt sektorsintressenter. För dessa kan rapporten ge ökad kunskap om tillståndet för samverkansmeritering vid svenska lärosäten och insikter om möjligheter för utveckling.Projektet har tagit fram ett utbildningsmaterial för att stödja fortsatt utvecklingsarbete på olika nivåer vid lärosäten samt en vägledning för att dokumentera och beskriva samverkansmeriter. Vägledningen kan användas för inspiration till lärare och forskare som vill sammanställa sina samverkansmeriter. De verktyg som presenteras i vägledningen kan också användas vid kompetensplanering, bedömningssituationer och medarbetarsamtal.Förhoppningen är att MerSam-projektet och denna rapport, dialog inom och mellan lärosäten samt mellan lärosäten och sektorsintressenter, bidrar till fortsatt utveckling av samverkansmeritering samt till att skapa en gemensam uppfattning om vad det betyder att meritera sig inom ramen för samverkansuppgiften.
  •  
14.
  • Bergstrand, Anna, 1974-, et al. (författare)
  • Varför är det så snårigt? : Begrepp relaterade till samverkansmeritering
  • 2021
  • Rapport (populärvet., debatt m.m.)abstract
    • Detta dokument är framtaget som en intern rapport inom MerSam – Meritvärde av samverkansskicklighet, varsprojekttid löpt under 2017 – 2020. MerSam är ett av Vinnovas 17 finansierade K3-projekt. Rapporten utgör ensammanställning av insamlad information från dokument, dialoger, workshoppar, intervjuer och enkäter.Rapporten visar på användning av begrepp och tolkning av begrepp. Syftet är att beskriva en nulägesbild ochutifrån den samla och lyfta fram vilka begrepp som förslagsvis kan användas i projektets slutleveranser. Slutsatser och rekommendationer har tagits fram med delaktighet av hela MerSam projektet och hardiskuterats på projektmöten, projektworkshopar den 17-18 juni 2020 samt den 15 oktober 2020. 
  •  
15.
  • Björn, Erik, et al. (författare)
  • Determination of platinum in human subcellular microsamples by inductively coupled plasma mass spectrometry
  • 2007
  • Ingår i: Analytical Biochemistry. - : Elsevier BV. - 0003-2697. ; 363, s. 135-42
  • Tidskriftsartikel (refereegranskat)abstract
    • A fast and robust method for the determination of platinum in human subcellular microsamples by inductively coupled plasma mass spectrometry was developed, characterized, and validated. Samples of isolated DNA and exosome fractions from human ovarian (2008) and melanoma (T289) cancer cell lines were used. To keep the sample consumption to approximately 10 μl and obtain a high robustness of the system, a flow injection sample introduction system with a 4.6-μl sample loop was used in combination with a conventional pneumatic nebulizer and a spray chamber. The system was optimized with respect to signal/noise ratio using a multivariate experimental design. The system proved to be well suited for routine analysis of large sample series, and several hundreds of samples could be analyzed without maintenance or downtime. The detection limit of the method was 0.12 pg (26 pg/g) platinum. To avoid systematic errors from nonspectral interferences, it was necessary to use reagent matched calibration standards or isotope dilution analysis. An uncertainty budget was constructed to estimate the total expanded uncertainty of the method, giving a quantification limit of 2.3 pg (0.5 ng/g) platinum in DNA samples. The uncertainty was sufficiently low to study quantitative differences in the formation of Pt–DNA adducts after treatment with cisplatin using different exposure times and concentrations.
  •  
16.
  • Borde, Annika, 1979, et al. (författare)
  • Preparation and evaluation of a freeze-dried oral killed cholera vaccine formulation
  • 2011
  • Ingår i: European journal of pharmaceutics and biopharmaceutics. - : Elsevier BV. - 0939-6411 .- 1873-3441. ; 79:3, s. 508-518
  • Tidskriftsartikel (refereegranskat)abstract
    • Different oral liquid cholera vaccines have proved to be safe and effective, but their formulations present problems for use in low-income countries, since large package volumes have to be transported and cold chain maintenance is required. A solid state formulation would here be more advantageous, and consequently, the possibility to develop a dry cholera vaccine formulation by freeze-drying was investigated. The ability of sucrose, trehalose and mannitol to provide process stabilization during freeze-drying was tested on a formalin-killed whole-cell Vibrio cholerae model vaccine. A matrix of sucrose or trehalose prevented bacterial aggregation, preserved cell morphology and maintained practically completely the protective lipopolysaccharide (LPS) antigen on the cell surface and its reactivity with specific antibody in vitro. After reconstitution, this formulation also retained the capacity to elicit a strong serum and gut mucosal anti-LPS antibody response in orally immunized mice, as compared to the corresponding liquid vaccine formulation. The full preservation of the in vivo immunogenicity was also maintained when the internationally widely licensed oral cholera vaccine Dukoral (TM), which comprises a cocktail of inactivated V. cholerae together with cholera toxin B-subunit (CTB), was freeze-dried using sucrose for stabilization. Thus, we present a process generating a dry oral inactivated whole-cell cholera vaccine formulation with attractive features for public health use in cholera-afflicted settings.
  •  
17.
  • Brackmann, Christian, et al. (författare)
  • Laser-induced fluorescence of formaldehyde in combustion using third harmonic Nd : YAG laser excitation
  • 2003
  • Ingår i: Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy. - 1386-1425. ; 59:14, s. 3347-3356
  • Tidskriftsartikel (refereegranskat)abstract
    • Formaldehyde (CH2O) is an important intermediate species in combustion processes and it can through laser-induced fluorescence measurements be used for instantaneous flame front detection. The present study has focussed on the use of the third harmonic of a Nd:YAG laser at 355 nm as excitation wavelength for formaldehyde, and different dimethyl ether (C2H6O) flames were used as sources of formaldehyde in the experiments. The investigations included studies of the overlap between the laser profile and the absorption lines of formaldehyde, saturation effects and the potential occurrence of laser-induced photochemistry. The technique was applied for detection of formaldehyde in an internal combustion engine operated both as a spark ignition engine and as a homogenous charge compression ignition engine. (C) 2003 Elsevier B.V. All rights reserved.
  •  
18.
  • Bragadottir, Gudrun, et al. (författare)
  • Low-dose vasopressin increases glomerular filtration rate, but impairs renal oxygenation in post-cardiac surgery patients.
  • 2009
  • Ingår i: Acta Anaesthesiol Scand. - : Wiley. - 1399-6576. ; 53:8, s. 1052-9
  • Tidskriftsartikel (refereegranskat)abstract
    • BACKGROUND: The beneficial effects of vasopressin on diuresis and creatinine clearance have been demonstrated when used as an additional/alternative therapy in catecholamine-dependent vasodilatory shock. A detailed analysis of the effects of vasopressin on renal perfusion, glomerular filtration, excretory function and oxygenation in man is, however, lacking. The objective of this pharmacodynamic study was to evaluate the effects of low to moderate doses of vasopressin on renal blood flow (RBF), glomerular filtration rate (GFR), renal oxygen consumption (RVO2) and renal oxygen extraction (RO2Ex) in post-cardiac surgery patients. METHODS: Twelve patients were studied during sedation and mechanical ventilation after cardiac surgery. Vasopressin was sequentially infused at 1.2, 2.4 and 4.8 U/h. At each infusion rate, systemic haemodynamics were evaluated by a pulmonary artery catheter, and RBF and GFR were measured by the renal vein thermodilution technique and by renal extraction of 51chromium-ethylenediaminetetraacetic acid, respectively. RVO2 and RO2Ex were calculated by arterial and renal vein blood samples. RESULTS: The mean arterial pressure was not affected by vasopressin while cardiac output and heart rate decreased. RBF decreased and GFR, filtration fraction, sodium reabsorption, RVO2, RO2Ex and renal vascular resistance increased dose-dependently with vasopressin. Vasopressin exerted direct antidiuretic and antinatriuretic effects. CONCLUSIONS: Short-term infusion of low to moderate, non-hypertensive doses of vasopressin induced a post-glomerular renal vasoconstriction with a decrease in RBF and an increase in GFR in post-cardiac surgery patients. This was accompanied by an increase in RVO2, as a consequence of the increases in the filtered tubular load of sodium. Finally, vasopressin impaired the renal oxygen demand/supply relationship.
  •  
19.
  • Chambi, Diego, et al. (författare)
  • Production of Exopolysaccharides by Cultivation of Halotolerant Bacillus atrophaeus BU4 in Glucose- and Xylose-Based Synthetic Media and in Hydrolysates of Quinoa Stalks
  • 2022
  • Ingår i: Fermentation. - : MDPI AG. - 2311-5637. ; 8:2
  • Tidskriftsartikel (refereegranskat)abstract
    • A halotolerant, exopolysaccharide-producing bacterium isolated from the Salar de Uyuni salt flat in Bolivia was identified as Bacillus atrophaeus using next-generation sequencing. Comparisons indicate that the genome most likely (p-value: 0.0024) belongs to a subspecies previously not represented in the database. The growth of the bacterial strain and its ability to produce exopolysaccharides (EPS) in synthetic media with glucose or xylose as carbon sources, and in hydrolysates of quinoa stalks, was investigated. The strain grew well in all synthetic media, but the growth in glucose was better than that in xylose. Sugar consumption was better when initial concentrations were low. The growth was good in enzymatically produced cellulosic hydrolysates but was inhibited in hemicellulosic hydrolysates produced using hydrothermal pretreatment. The EPS yields were up to 0.064 g/g on initial glucose and 0.047 g/g on initial xylose, and was higher in media with relatively low sugar concentrations. The EPS was isolated and purified by a sequential procedure including centrifugation, cold ethanol precipitation, trichloroacetic acid treatment, dialysis, and freeze-drying. Glucose and mannose were the main sugars identified in hydrolyzed EPS. The EPS was characterized by size-exclusion chromatography, Fourier-transform infrared (FTIR) spectroscopy, heteronuclear single-quantum coherence nuclear magnetic resonance (HSQC NMR) spectroscopy, scanning electron microscopy, X-ray diffraction, and thermogravimetric analysis. No major differences were elucidated between EPS resulting from cultivations in glucose- or-xylose-based synthetic media, while some divergences with regard to molecular-weight averages and FTIR and HSQC NMR spectra were detected for EPS from hydrolysate-based media.
  •  
20.
  • Damén, Tor, et al. (författare)
  • Atrial natriuretic peptide does not degrade the endothelial glycocalyx: A secondary analysis of a randomized porcine model
  • 2021
  • Ingår i: Acta Anaesthesiologica Scandinavica. - : Wiley. - 0001-5172 .- 1399-6576. ; 65:9, s. 1305-1312
  • Tidskriftsartikel (refereegranskat)abstract
    • Background: The atrial natriuretic peptide (ANP) released from the heart regulates intravascular volume and is suspected to increase capillary permeability. Contradictory results regarding ANP and glycocalyx degradation have been reported. The aim of this study was to investigate if an infusion of ANP causes degradation of the endothelial glycocalyx. Methods: Twenty pigs, pretreated with 250mg methylprednisolone, were randomized to receive an infusion of either ANP (50ng/kg/min) (n=10) or 0.9% NaCl (n=10) during 60min. Endothelial glycocalyx components (heparan sulphate proteoglycan and hyaluronic acid), Hct, calculated plasma volume and colloid osmotic pressure were measured from baseline to 60min. Results: There was no difference between the control and intervention groups for heparan sulphate proteoglycan and hyaluronic acid corrected for the change in plasma volume (P=.333 and 0.197). Hct increased with 1.8±2.2% in the intervention group (P=.029) with no change −0.5±2.3% in the control group (P=.504). The plasma volume decreased in the intervention group with −8.4±10% (P=.034) with no change in the control group 3.1±12% (P=.427). Median changes in colloid osmotic pressures in the control and intervention group were −0.39 [95% CI, −1.88-0.13] and 0.9 [95% CI, 0.00-1.58], respectively (P=.012). Conclusions: In this randomized porcine study, an ANP infusion did not cause endothelial glycocalyx degradation but decreased the plasma volume most probably due to precapillary vasodilation and increased filtration. © 2021 The Acta Anaesthesiologica Scandinavica Foundation. Published by John Wiley & Sons Ltd
  •  
21.
  • Damén, Tor, et al. (författare)
  • Effects of different mean arterial pressure targets on plasma volume, ANP and glycocalyx-A randomized trial.
  • 2021
  • Ingår i: Acta anaesthesiologica Scandinavica. - : Wiley. - 1399-6576 .- 0001-5172. ; 65:2, s. 220-227
  • Tidskriftsartikel (refereegranskat)abstract
    • Arterial haematocrit (Hct) has been shown to decrease after anaesthesia induction, most probably because of an increased plasma volume (PV). The primary objective was to quantify change in PV if mean arterial pressure (MAP) was kept at baseline level or allowed to decrease to 60mm Hg. Our secondary objective was to evaluate underlying mechanisms of this response.Twenty-four coronary artery bypass patients were randomized to a higher (90mm Hg, intervention group) or lower (60mm Hg, control group) MAP by titration of norepinephrine. During the experimental procedure, no fluids were administered. Baseline PV was measured by 125 I-albumin and the change in PV was calculated from the change in Hct. Changes in MAP, plasma 125 I-albumin, colloid osmotic pressure, albumin, Mid Regional-pro Atrial Natriuretic Peptide (MR-proANP) and endothelial glycocalyx components were measured from baseline to 50minutes after anaesthesia induction.The MAP during the trial was 93±9mm Hg in the intervention group and 62±5mm Hg in the control group. PV increased with up to 420±180mL in the control group and 45±130mL in the intervention group (P<.001). Albumin and colloid osmotic pressure decreased significantly more in the control group. MR-proANP increased in the control group but no shedding of the glycocalyx layer was detected in either of the groups.Allowing mean arterial pressure to fall to 60mm Hg during anaesthesia induction, increases the plasma volume due to reabsorption of interstitial water, with no ANP-induced degradation of the endothelial glycocalyx.
  •  
22.
  • Folkenant, Matilda, et al. (författare)
  • Structure and properties of Cr–C/Ag films deposited by magnetron sputtering
  • 2015
  • Ingår i: Surface & Coatings Technology. - : Elsevier. - 0257-8972 .- 1879-3347. ; 281, s. 184-192
  • Tidskriftsartikel (refereegranskat)abstract
    • Cr–C/Ag thin films with 0–14 at.% Ag have been deposited by magnetron sputtering from elemental targets. The samples were analyzed by X-ray diffraction, transmission electron microscopy, X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM) to study their structure and chemical bonding. A complex nanocomposite structure consisting of three phases; nanocrystalline Ag, amorphous CrCx and amorphous carbon is reported. The carbon content in the amorphous carbide phase was determined to be 32–33 at.% C, independent of Ag content. Furthermore, SEM and XPS results showed higher amounts of Ag on the surface compared to the bulk. The hardness and Young's modulus were reduced from 12 to 8 GPa and from 270 to 170 GPa, respectively, with increasing Ag content. The contact resistance was found to decrease with Ag addition, with the most Ag rich sample approaching the values of an Ag reference sample. Initial tribological tests gave friction coefficients in the range of 0.3 to 0.5, with no clear trends. Annealing tests show that the material is stable after annealing at 500 °C for 1 h, but not after annealing at 800 °C for 1 h. In combination, these results suggest that sputtered Cr–C/Ag films could be potentially applicable for electric contact applications.
  •  
23.
  • Frost, Britt-Marie, et al. (författare)
  • Translocation t(12;21) is related to in vitro cellular drug sensitivity to doxorubicin and etoposide in childhood acute lymphoblastic leukemia
  • 2004
  • Ingår i: Blood. - Washington : American society of hematology. - 0006-4971 .- 1528-0020. ; 104:8, s. 2452-2457
  • Tidskriftsartikel (refereegranskat)abstract
    • The t(12;21) (p13;q22) translocation resulting in ETV6/RUNX1 (previously named TEL/AML1) gene fusion is present in about 25% of children with precursor B-lineage acute lymphoblastic leukemia (B-ALL). We successfully tested 275 precursor BALL samples from children aged 1 to 17 years to determine the relation between t(12;21) and in vitro cellular drug resistance, measured by the fluorometric microculture cytotoxicity assay (FMCA). Samples from 83 patients (30%) were positive for t(12;21). The ETV6/RUNX1(+) samples were significantly more sensitive than ETV6/RUNX1(-) samples to doxorubicin, etoposide, amsacrine, and dexamethasone, whereas the opposite was true for cytarabine. After matching for unevenly distributed patient characteristics, that is, excluding patients with high hyperdiploidy (> 51 chromosomes), t(g;22), t(1;19), or 11q23 rearrangement, the ETV6/RUNX1(+) samples remained significantly more sensitive to doxorubicin (P = .001) and etoposide (P = .001). For the other drugs tested (amsacrine, cytarabine, dexamethasone, prednisolone, vincristine, 6-thioguanine, and 4-hydroper-oxy-cyclophosphamide), no significant difference in cellular drug sensitivity was found. In conclusion, we found that the presence of the t(12;21) translocation in childhood precursor B-ALL is associated with a high tumor cell sensitivity to doxorubicin and etoposide. High throughput techniques should now be used to elucidate the cellular mechanisms by which ETV6/RUNX1 gene fusion is linked to increased sensitivity to these drugs.
  •  
24.
  • Gefen, Amit, et al. (författare)
  • Fluid handling by foam wound dressings : From engineering theory to advanced laboratory performance evaluations
  • 2024
  • Ingår i: International Wound Journal. - : John Wiley & Sons. - 1742-4801 .- 1742-481X. ; 21:2
  • Forskningsöversikt (refereegranskat)abstract
    • This article describes the contemporary bioengineering theory and practice of evaluating the fluid handling performance of foam-based dressings, with focus on the important and clinically relevant engineering structure-function relationships and on advanced laboratory testing methods for pre-clinical quantitative assessments of this common type of wound dressings. The effects of key wound dressing material-related and treatment-related physical factors on the absorbency and overall fluid handling of foam-based dressings are thoroughly and quantitively analysed. Discussions include exudate viscosity and temperature, action of mechanical forces and the dressing microstructure and associated interactions. Based on this comprehensive review, we propose a newly developed testing method, experimental metrics and clinical benchmarks that are clinically relevant and can set the standard for robust fluid handling performance evaluations. The purpose of this evaluative framework is to translate the physical characteristics and performance determinants of a foam dressing into achievable best clinical outcomes. These guiding principles are key to distinguishing desirable properties of a dressing that contribute to optimal performance in clinical settings.
  •  
25.
  • George-Chandy, Annie, 1969, et al. (författare)
  • Th17 development and autoimmune arthritis in the absence of reactive oxygen species
  • 2008
  • Ingår i: European Journal of Immunology. - : Wiley. - 0014-2980 .- 1521-4141. ; 38:4, s. 1118-1126
  • Tidskriftsartikel (refereegranskat)abstract
    • Dendritic cells (DC) express a functional NADPH oxidase and produce reactive oxygen species (ROS) upon interaction with microbes and T cells. Exposure to ROS leads to DC activation and maturation, as evidenced by phenotypic and functional changes. We have evaluated how endogenous ROS production affects the cytokine secretion pattern and T cell-activating capacity of bone marrow-derived murine DC. DC treated with ROS scavengers, as well as DC from mice that lack a functional NADPH oxidase (and thereby inherently deficient in ROS production) produced significantly increased levels of IL-1β, IL-6, TNF-α and TGF-β in response to microbial activation. DC deficient in ROS production induced high levels of IFN-γ and IL-17 in responding T cells after Ag-specific or superantigen-induced activation. Finally, we show that ROS deficiency affected the induction of a T cell-dependent inflammatory condition, collagen-induced arthritis (CIA). C57BL/6 mice that lack a functional NADPH oxidase developed a severe and erosive CD4-dependent CIA, whereas the majority of the congenic wild-type animals remained healthy. These data suggest that ROS act as immunomodulators in DC-driven T cell activation and perhaps also in T cell-dependent immunopathology. 
  •  
26.
  •  
27.
  • Gonzales, Lucia, et al. (författare)
  • Alkaline pH Is a Signal for Optimal Production and Secretion of the Heat Labile Toxin, LT in Enterotoxigenic Escherichia Coli (ETEC)
  • 2013
  • Ingår i: PLOS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 8:9
  • Tidskriftsartikel (refereegranskat)abstract
    • Enterotoxigenic Escherichia coli (ETEC) cause secretory diarrhea in children and travelers to endemic areas. ETEC spreads through the fecal-oral route. After ingestion, ETEC passes through the stomach and duodenum before it colonizes the lower part of the small intestine, exposing bacteria to a wide range of pH and environmental conditions. This study aimed to determine the impact of external pH and activity of the Cyclic AMP receptor protein (CRP) on the regulation of production and secretion of heat labile (LT) enterotoxin. ETEC strain E2863wt and its isogenic mutant E2863ΔCRP were grown in LBK media buffered to pH 5, 7 and 9. GM1 ELISA, cDNA and cAMP analyses were carried out on bacterial pellet and supernatant samples derived from 3 and 5 hours growth and from overnight cultures. We confirm that CRP is a repressor of LT transcription and production as has been shown before but we show for the first time that CRP is a positive regulator of LT secretion both in vitro and in vivo. LT secretion increased at neutral to alkaline pH compared to acidic pH 5 where secretion was completely inhibited. At pH 9 secretion of LT was optimal resulting in 600 percent increase of secreted LT compared to unbuffered LBK media. This effect was not due to membrane leakage since the bacteria were viable at pH 9. The results indicate that the transition to the alkaline duodenum and/or exposure to high pH close to the epithelium as well as activation of the global transcription factor CRP are signals that induce secretion of the LT toxin in ETEC.
  •  
28.
  • Grimm, Sebastian, et al. (författare)
  • Selection and characterisation of affibody molecules inhibiting the interaction between Ras and Raf in vitro
  • 2010
  • Ingår i: NEW BIOTECHNOL. - : Elsevier BV. - 1871-6784. ; 27:6, s. 766-773
  • Tidskriftsartikel (refereegranskat)abstract
    • Development of molecules with the ability to selectively inhibit particular protein-protein interactions is important in providing tools for understanding cell biology In this work, we describe efforts to select small Ras- and Raf-specific three-helix bundle affibody binding proteins capable of inhibiting the interaction between H-Ras and Raf-1, from a combinatorial library displayed on bacteriophage Target-specific variants with typically high nanomolar or low micromolar affinities (K-D) could be selected successfully against both proteins, as shown by dot blot, ELISA and real-time biospecific interaction analyses Affibody molecule variants selected against H-Ras were shown to bind epitopes overlapping each other at a site that differed from that at which H-Ras interacts with Raf-1 In contrast, an affibody molecule isolated during selection against Raf-1 was shown to effectively inhibit the interaction between H-Ras and Raf-1 in a dose-dependent manner Possible intracellular applications of the selected affibody molecules are discussed
  •  
29.
  •  
30.
  • Haeger-Eugensson, Marie, et al. (författare)
  • Air Quality Modeling in Dense Urban Areas at Ground Level—CFD, OSM or Gauss?
  • 2021
  • Ingår i: Springer Proceedings in Complexity. - Berlin, Heidelberg : Springer Berlin Heidelberg. - 2213-8684 .- 2213-8692. ; , s. 265-270
  • Konferensbidrag (refereegranskat)abstract
    • There is an ongoing intensive urban densification in many cities. The need for advanced modeling methods that realistically simulate dispersion at ground level in complex urban areas have increased. As more modeling is done outside usual model communities, guidelines supporting the selection of suitable models is needed. Dispersion of air pollutants in street canyons is affected by width, height, length and building structure. Studies show that concentration of NO2 in street canyons can become 5-times higher, compared to open conditions. Since Gaussian models cannot simulate dispersion at ground level in dense urban settlements models that include 3D information (buildings) is therefore required, such as CFD or OSM models to obtain realistic results. The purpose of the project is to investigate the effect from building on air quality and giving recommendations to authorities and consultants helping with model choices. This is based on calculations with three different model types, CFD, OSM and Gaussian for four urban environments, from dense to open suburban areas using the same input. Validation was done with continuous measurements of NO2 at each site. The CFD modeling gave best results at all sites, the OSM modeling quality varied between the sites, with slight to about 50% underestimation. The Gaussian modeling generally underestimated the concentration with 50%. The aspect ratio H/W ≥ 0.7 favors development of vortices and lateral dispersion of pollutants in street canyons. It was shown that with at least this aspect ratio locally emitted NO2 frequently becomes at least 2–3 times higher compared an open road case. A methodology has been developed visualized in a flow chart, for help choosing an appropriate model for each environment. Most important factors are; street canyon structure; local concentration level; proximity to high emissions/risk of leakage into calculation area.
  •  
31.
  • Hemström, Petrus, et al. (författare)
  • Alternative organic solvents for HILIC separation of cisplatin species with on-line ICP-MS detection
  • 2008
  • Ingår i: Journal of Separation Science. - : John Wiley & Sons. - 1615-9306 .- 1615-9314. ; 31:4, s. 599-603
  • Tidskriftsartikel (refereegranskat)abstract
    • Several low volatile organic solvents were evaluated as organic modifiers in eluents for HILIC separations of cisplatin species to optimize the on-line coupling of HILIC to inductively coupled plasma MS (ICP-MS). The aim was to identify a solvent giving low solvent vapor loading of the ICP, to maximize analyte sensitivity and minimize carbon depositions on instrumental parts, while retaining chromatographic performance. The best overall performance of the HILIC-ICP-MS system for the analysis of cisplatin was achieved using 1,4-dioxane as eluent, yielding high retention and an HILIC type retention mechanism, at the expense of a 50% drop in column efficiency due to the higher viscosity of 1,4-dioxane compared to the more commonly used HILIC solvent ACN. Using 1,4-dioxane as solvent in HILIC provides the best compromise between carbon deposition and separation efficiency among a series of high-boiling water-miscible solvents tested.
  •  
32.
  • Holmgren, Jan, 1944, et al. (författare)
  • Development and preclinical evaluation of safety and immunogenicity of an oral ETEC vaccine containing inactivated E. coli bacteria overexpressing colonization factors CFA/I, CS3, CS5 and CS6 combined with a hybrid LT/CT B subunit antigen, administered alone and together with dmLT adjuvant
  • 2013
  • Ingår i: Vaccine. - : Elsevier BV. - 0264-410X .- 1873-2518. ; 31:20, s. 2457-2464
  • Tidskriftsartikel (refereegranskat)abstract
    • A first-generation oral inactivated whole-cell enterotoxigenic Escherichia coli (ETEC) vaccine, comprising formalin-killed ETEC bacteria expressing different colonization factor (CF) antigens combined with cholera toxin B subunit (CTB), when tested in phase III studies did not significantly reduce overall (generally mild) ETEC diarrhea in travelers or children although it reduced more severe ETEC diarrhea in travelers by almost 80%. We have now developed a novel more immunogenic ETEC vaccine based on recombinant non-toxigenic E. coli strains engineered to express increased amounts of CF antigens, including CS6 as well as an ETEC-based B subunit protein (LCTB. A), and the optional combination with a nontoxic double-mutant heat-labile toxin (LT) molecule (dmLT) as an adjuvant.Two test vaccines were prepared under GMP: (1) A prototype E. coli CFA/I-only formalin-killed whole-cell. +. LCTB. A vaccine, and (2) A "complete" inactivated multivalent ETEC-CF (CFA/I, CS3, CS5 and CS6 antigens) whole-cell. +. LCTB. A vaccine. These vaccines, when given intragastrically alone or together with dmLT in mice, were well tolerated and induced strong intestinal-mucosal IgA antibody responses as well as serum IgG and IgA responses to each of the vaccine CF antigens as well as to LT B subunit (LTB). Both mucosal and serum responses were further enhanced (adjuvanted) when the vaccines were co-administered with dmLT. We conclude that the new multivalent oral ETEC vaccine, both alone and especially in combination with the dmLT adjuvant, shows great promise for further testing in humans. 
  •  
33.
  • Holmgren, Jan, 1944, et al. (författare)
  • Mucosal adjuvants and anti-infection and anti-immunopathology vaccines based on cholera toxin, cholera toxin B subunit and CpG DNA
  • 2005
  • Ingår i: Immunology Letters. - : Elsevier. - 0165-2478 .- 1879-0542. ; 97:2, s. 181-8
  • Tidskriftsartikel (refereegranskat)abstract
    • Mucosal immunisation may be used both to protect the mucosal surfaces against infections and as a means for immunological treatment of peripheral immunopathological disorders through the induction of systemic antigen-specific tolerance ('oral tolerance'). The development of mucosal vaccines, whether for prevention of infectious diseases or for oral tolerance immunotherapy, requires efficient antigen delivery and adjuvant systems that can help to present the appropriate vaccine or immunotherapy antigens to the mucosal immune system. The most potent (but also toxic) mucosal adjuvants are cholera toxin (CT) and the closely related Escherichia coli heat-labile enterotoxin (LT), and much effort and significant progress have been made recently to generate toxicologically acceptable derivatives of these toxins with retained adjuvant activity. Among these are the non-toxic, recombinantly produced cholera toxin B-subunit (CTB). CTB is a specific protective antigen component of a widely registered oral cholera vaccine as well as a promising vector for either giving rise to mucosal anti-infective immunity or for inducing peripheral anti-inflammatory tolerance to chemically or genetically linked foreign antigens administered mucosally. CT and CTB have also recently been used as combined vectors and adjuvants for markedly promoting ex vivo dendritic cell (DC) vaccination with different antigens and also steering the immune response to the in vivo-reinfused DCs towards either broad Th1 + Th2 + CTL immunity (CT) or Th2 or tolerance (CTB). Another type of mucosal adjuvants is represented by bacterial DNA or synthetic oligodeoxynucleotides containing CpG-motifs, which especially when linked to CTB have been found to effectively stimulate both innate and adaptive mucosal immune responses. The properties and clinical potential of these different classes of adjuvants are being discussed. © 2004 Elsevier B.V. All rights reserved.
  •  
34.
  • Hult, Johan, et al. (författare)
  • Quantitative three-dimensional imaging of soot volume fraction in turbulent non-premixed flames
  • 2002
  • Ingår i: Experiments in Fluids. - : Springer Science and Business Media LLC. - 1432-1114 .- 0723-4864. ; 33:2, s. 265-269
  • Tidskriftsartikel (refereegranskat)abstract
    • A three-dimensional (3-D) imaging system for studies of reactive and non-reactive flows is described. It can be used to reveal the topology of turbulent structures and to extract 3-D quantities, such as concentration gradients. Measurements are performed using a high repetition rate laser and detector system in combination with a scanning mirror. In this study, the system is used for laser-induced incandescence measurements to obtain quantitative 3-D soot volume fraction distributions in both laminar and turbulent non-premixed flames. From the acquired data, iso-concentration surfaces are visualised and concentration gradients calculated.
  •  
35.
  •  
36.
  • Karlsson, S. L., et al. (författare)
  • Development of stable vibrio cholerae O1 Hikojima type vaccine strains co-expressing the Inaba and Ogawa lipopolysaccharide antigens
  • 2014
  • Ingår i: PLOS ONE. - : Public Library of Science. - 1932-6203. ; 9:11
  • Tidskriftsartikel (refereegranskat)abstract
    • We describe here the development of stable classical and El Tor V. cholerae O1 strains of the Hikojima serotype that co-express the Inaba and Ogawa antigens of O1 lipopolysaccharide (LPS). Mutation of the wbeTgene reduced LPS perosamine methylation and thereby gave only partial transformation into Ogawa LPS on the cell surface. The strains express approximately equal amounts of Inaba-and Ogawa-LPS antigens which are preserved after formalin-inactivation of the bacteria. Oral immunizations of both inbred and outbred mice with formalin-inactivated whole-cell vaccine preparations of these strains elicited strong intestinal IgA anti-LPS as well as serum vibriocidal antibody responses against both Inaba and Ogawa that were fully comparable to the responses induced by the licensed Dukoral vaccine. Passive protection studies in infant mice showed that immune sera raised against either of the novel Hikojima vaccine strains protected baby mice against infection with virulent strains of both serotypes. This study illustrates the power of using genetic manipulation to improve the properties of bacteria strains for use in killed whole-cell vaccines.
  •  
37.
  • Kehoe, Laura, et al. (författare)
  • Make EU trade with Brazil sustainable
  • 2019
  • Ingår i: Science. - : American Association for the Advancement of Science (AAAS). - 0036-8075 .- 1095-9203. ; 364:6438, s. 341-
  • Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)
  •  
38.
  • Kolsrud, Oscar, et al. (författare)
  • Effects of atrial natriuretic peptide on renal function during cardiopulmonary bypass: a randomized pig model.
  • 2020
  • Ingår i: European journal of cardio-thoracic surgery : official journal of the European Association for Cardio-thoracic Surgery. - : Oxford University Press (OUP). - 1873-734X. ; 57:4, s. 652-659
  • Tidskriftsartikel (refereegranskat)abstract
    • Acute kidney injury is a well-known complication after cardiac surgery and cardiopulmonary bypass (CPB). In this experimental animal study, we evaluated the effects of atrial natriuretic peptide (ANP) on renal function, perfusion, oxygenation and tubular injury during CPB.Twenty pigs were blindly randomized to continuous infusion of either ANP (50ng/kg/min) or placebo before, during and after CPB. Renal blood flow as well as cortical and medullary perfusion was measured. Blood was repeatedly sampled from the renal vein. Glomerular filtration rate was measured by infusion clearance of 51Cr-EDTA.Glomerular filtration rate was higher (P<0.001), whereas renal blood flow or renal oxygen delivery was not affected by ANP during CPB. Renal oxygen consumption did not differ between groups during CPB, whereas renal oxygen extraction was higher in the ANP group (P=0.03). Urine flow and sodium excretion were higher in the ANP group during CPB. Blood flow in the renal medulla, but not in the cortex, dropped during CPB, an effect that was not seen in the animals that received ANP.ANP improved renal function during CPB. Despite impaired renal oxygenation, ANP did not cause tubular injury, suggesting a renoprotective effect of ANP during CPB. Also, CPB induced a selectively reduced blood flow in the renal medulla, an effect that was counteracted by ANP.
  •  
39.
  • Lebens, Michael, 1956, et al. (författare)
  • Construction and preclinical evaluation of mmCT, a novel mutant cholera toxin adjuvant that can be efficiently produced in genetically manipulated Vibrio cholerae
  • 2016
  • Ingår i: Vaccine. - : Elsevier Ltd. - 0264-410X .- 1873-2518. ; 34:18, s. 2121-2128
  • Tidskriftsartikel (refereegranskat)abstract
    • There is an urgent need for new adjuvants that are effective with mucosally administered vaccines. Cholera toxin (CT) is the most powerful known mucosal adjuvant but is much too toxic for human use. In an effort to develop a useful mucosal adjuvant we have generated a novel non-toxic mutant CT molecule that retains much of the adjuvant activity of native CT. This was achieved by making the enzymatically active A subunit (CTA) recalcitrant to the site-specific proteolytic cleavage ("nicking") required for toxicity, which was found to require mutations not only in the two residues rendering the molecule resistant to trypsin but also in neighboring sites protecting against cleavage by Vibrio cholerae proteases. This multiple-mutated CT (mmCT) adjuvant protein could be efficiently produced in and purified from the extracellular medium of CT-deleted V. cholerae. The mmCT completely lacked detectable enterotoxicity in an infant mouse model and had >1000-fold reduced cAMP inducing activity compared to native CT in a sensitive mammalian target cell system. It nonetheless proved to have potent adjuvant activity on mucosal and systemic antibody as well as cellular immune responses to mucosally co-administered antigens including oral cholera and intranasal influenza vaccines. We conclude that mmCT is an attractive novel non-toxic mucosal adjuvant for enhancing immune responses to co-administered mucosal vaccines
  •  
40.
  • Lebens, Michael, 1956, et al. (författare)
  • Construction of novel vaccine strains of Vibrio cholerae co-expressing the Inaba and Ogawa serotype antigens
  • 2011
  • Ingår i: Vaccine. - : Elsevier BV. - 0264-410X .- 1873-2518. ; 29:43, s. 7505-7513
  • Tidskriftsartikel (refereegranskat)abstract
    • The approach of inducing protective immunity against cholera by oral vaccination with killed whole Vibrio cholerae cells is effective, but the complexity of current cholera vaccines makes them difficult and relatively expensive to manufacture, especially if recombinant cholera toxin B subunit is included in the formulation. In an effort to simplify the composition of a new generation of oral cholera vaccines we have generated a novel non-toxigenic candidate vaccine strain of V. cholerae O1 that stably expresses both the Ogawa and Inaba serotype antigens on its surface. This was done by introducing a functional wbeT gene without a functional promoter into the chromosome of an O1 Inaba strain. The resulting low levels of expression of the wbeT gene product allowed for the desired partial serotype switching. This strain (MS1342) can potentially replace the three virulent strains used in currently manufactured cholera vaccines. Oral immunization of mice with formalin-killed MS1342 bacteria gave rise to Ogawa-specific, Inaba-specific and cross-reactive serum antibodies that were detectable both by lipopolysaccharide (LPS)-specific ELISAs and as vibriocidal antibodies that are considered to predict protective efficacy. These responses as well as intestinal mucosal IgA anti-LPS antibody responses were fully comparable with those obtained by immunization with the internationally licensed oral cholera vaccine Dukoral ®. We propose that such a strain may form the basis of a single strain killed whole cell cholera vaccine protecting against cholera caused by either the Inaba or Ogawa serotype of V. cholerae O1. 
  •  
41.
  • Lin, Pei-yan, et al. (författare)
  • Catalytic purification of car exhausts over cobalt- and copper-based metal oxides promoted with platinum and rhodium
  • 1995
  • Ingår i: Applied Catalysis B: Environmental. - : Elsevier BV. - 0926-3373 .- 1873-3883. ; 6:3, s. 237-319
  • Tidskriftsartikel (refereegranskat)abstract
    • 25 Alumina-and silica-supported oxide-based catalysts were prepared, with the overall metal composition La(0.45)Sr(0.15)Ce(0.35)Zr(0.05)M(1.0) (M=Co or Cu) and promoted with 0-0.5 mg Pt-Rh per gram catalyst. The catalysts were evaluated with respect to light-off temperatures and redox characteristics, using NO/CO/C3H6/O2/N2 gas mixtures to simulate car exhaust. The activities for complete oxidation of propene and carbon monoxide increased with increasing content of metal oxides and noble metals. The catalysts were characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) combined with energy-dispersive spectroscopy (EDS) analysis, temperature-programmed reduction (TPR), and specific surface area measurements (BET). SEM/TEM/XRD revealed that the alumina-supported catalysts contained well dispersed oxides of the added elements, whereas the silica-supported catalysts contained significantly larger particles of the copper or cobalt oxides, The TPR peak for reduction of cobalt oxide shifted toward lower temperatures with increasing content of Pt-Rh, indicating hydrogen spill-over from the noble metals to the cobalt oxide. The catalytic activity of the Co-based oxides supported on alumina and promoted with 0.49 mg Pt-Rh per gram catalysts was comparable to the activity of a commercial three-way catalyst (TWC), containing more than 4 times as much Pt-Rh.
  •  
42.
  •  
43.
  • Mattsson, Susanne, et al. (författare)
  • Internet-based stepped care with interactive support and cognitive behavioral therapy for reduction of anxiety and depressive symptoms in cancer : a clinical trial protocol
  • 2013
  • Ingår i: BMC Cancer. - : Springer Science and Business Media LLC. - 1471-2407. ; 13, s. 414-
  • Tidskriftsartikel (refereegranskat)abstract
    • Background: Approximately 20-30% of patients with cancer experience a clinically relevant level of emotional distress in response to disease and treatment. This in itself is alarming but it is even more problematic because it is often difficult for physicians and nurses to identify cancer patients who experience clinically relevant levels of anxiety and depression symptoms. This can result in persistent distress and can cause human suffering as well as costs for individuals and to the community. Methods: Applying a multi-disciplinary and design-oriented approach aimed at attaining new evidence-based knowledge in basic and applied psychosocial oncology, this protocol will evaluate an intervention to be implemented in clinical practice to reduce cancer patient anxiety and depression. A prospective randomized design will be used. The overarching goal of the intervention is to promote psychosocial health among patients suffering from cancer by means of self-help programmes delivered via an Internet platform. Another goal is to reduce costs for individuals and society, caused by emotional distress in response to cancer. Following screening to detect levels of patient distress, patients will be randomized to standard care or a stepped care intervention. For patients randomized to the intervention, step 1 will consist of self-help material, a chat forum where participants will be able to communicate with each other, and a Frequently Asked Questions (FAQ) section where they can ask questions and get answers from an expert. Patients in the intervention group who still report symptoms of anxiety or depression after access to step 1 will be offered step 2, which will consist of cognitive behavioral therapy (CBT) administered by a personal therapist. The primary end point of the study is patients' levels of anxiety and depression, evaluated longitudinally during and after the intervention. Discussion: There is a lack of controlled studies of the psychological and behavioral processes involved in this type of intervention for anxiety and depressive disorders. Since anxiety and depressive symptoms are relatively common in patients with cancer and the availability of adequate support efforts is limited, there is a need to develop evidence-based stepped care for patients with cancer, to be delivered via the Internet.
  •  
44.
  •  
45.
  • Nygren, Andreas, 1967, et al. (författare)
  • Norepinephrine and intestinal mucosal perfusion in vasodilatory shock after cardiac surgery
  • 2007
  • Ingår i: Shock. - : Ovid Technologies (Wolters Kluwer Health). - 1073-2322. ; 28:5, s. 536-543
  • Tidskriftsartikel (refereegranskat)abstract
    • Patients with norepinephrine-dependent vasodilatory shock after cardiac surgery (n = 10) were compared with uncomplicated postcardiac surgery patients (n = 10) with respect to jejunal mucosal perfusion, gastric-arterial PCO2 gradient, and splanchnic oxygen demand/supply relationship. Furthermore, the effects of norepinephrine-induced variations in MAP on these variables were evaluated in vasodilatory shock. Norepinephrine infusion rate was randomly and sequentially titrated to target MAPs of 60, 75, and 90 mmHg (0.25 +/- 0.24, 0.37 +/- 0.21, and 0.55 +/- 0.39 mug/kg per minute, respectively). Data on jejunal mucosal perfusion, jejunal mucosal hematocrit, and red blood cell (RBC) velocity (laser Doppler flowmetry) as well as gastric-arterial PCO2 gradient (gastric tonometry) and splanchnic oxygen and lactate extraction (hepatic vein catheter) were obtained. Splanchnic oxygen extraction was 71 +/- 16% in the vasodilatory shock group and 41 +/- 9% in the control group (P < 0.001), whereas splanchnic lactate extraction did not differ between the two groups. Jejunal mucosal perfusion (61%; P < 0.001), RBC velocity (35%; P < 0.01), and arterial-gastric mucosal PCO2 gradient (150%; P < 0.001) were higher in the vasodilatory shock group compared with those of the control group. Jejunal mucosal perfusion, jejunal mucosal hematocrit, RBC velocity, arterial-gastric mucosal PCO2 gradient, splanchnic oxygen extraction, and splanchnic lactate extraction were not affected by increasing infusion rates of norepinephrine. In patients with norepinephrine-dependent vasodilatory shock after cardiac surgery, intestinal mucosal perfusion was higher, whereas splanchnic and gastric oxygen demand/supply relationships were impaired compared with postoperative controls, suggesting that intestinal mucosal perfusion is prioritized in vasodilatory shock. Increasing MAP from 60 to 90 mmHg with norepinephrine in clinical vasodilatory shock does not affect intestinal mucosal perfusion and gastric or global splanchnic oxygen demand/supply relationships.
  •  
46.
  • Nygren, Andreas, 1967, et al. (författare)
  • Norepinephrine causes a pressure-dependent plasma volume decrease in clinical vasodilatory shock.
  • 2010
  • Ingår i: Acta anaesthesiologica Scandinavica. - : Wiley. - 1399-6576 .- 0001-5172. ; 54:7, s. 814-20
  • Tidskriftsartikel (refereegranskat)abstract
    • BACKGROUND: Recent experimental studies have shown that a norepinephrine-induced increase in blood pressure induces a loss of plasma volume, particularly under increased microvascular permeability. We studied the effects of norepinephrine-induced variations in the mean arterial pressure (MAP) on plasma volume changes and systemic haemodynamics in patients with vasodilatory shock. METHODS: Twenty-one mechanically ventilated patients who required norepinephrine to maintain MAP > or =70 mmHg because of septic/postcardiotomy vasodilatory shock were included. The norepinephrine dose was randomly titrated to target MAPs of 60, 75 and 90 mmHg. At each target MAP, data on systemic haemodynamics, haematocrit, arterial and mixed venous oxygen content and urine flow urine were measured. Changes in the plasma volume were calculated as 100 x (Hct(pre)/Hct(post)-1)/ (1-Hct(pre)), where Hct(pre) and Hct(post) are haematocrits before and after intervention. RESULTS: Norepinephrine doses to obtain target MAPs of 60, 75 and 90 mmHg were 0.20+/-0.18, 0.29+/-0.18 and 0.42+/-0.31 microg/kg/min, respectively. From 60 to 90 mmHg, increases in the cardiac index (15%), systemic oxygen delivery index (25%), central venous pressure (CVP) (20%) and pulmonary artery occlusion pressure (33%) were seen, while the intrapulmonary shunt fraction was unaffected by norepinehrine. Plasma volume decreased by 6.5% and 9.4% (P<0.0001) when blood pressure was increased from 60 to 75 and 90 mmHg, respectively. MAP (P<0.02) independently predicted the decrease in plasma volume with norepinephrine but not CVP (P=0.19), cardiac index (P=0.73), norepinephrine dose (P=0.58) or urine flow (P=0.64). CONCLUSIONS: Norepinephrine causes a pressure-dependent decrease in the plasma volume in patients with vasodilatory shock most likely caused by transcapillary fluid extravasation.
  •  
47.
  • Nygren, Andreas, 1967, et al. (författare)
  • Vasopressin decreases intestinal mucosal perfusion: a clinical study on cardiac surgery patients in vasodilatory shock.
  • 2009
  • Ingår i: Acta anaesthesiologica Scandinavica. - : Wiley. - 1399-6576 .- 0001-5172. ; 53:5, s. 581-8
  • Tidskriftsartikel (refereegranskat)abstract
    • BACKGROUND: Low to moderate doses of vasopressin have been used in the treatment of cathecholamine-dependent vasodilatory shock in sepsis or after cardiac surgery. We evaluated the effects of vasopressin on jejunal mucosal perfusion, gastric-arterial pCO2 gradient and the global splanchnic oxygen demand/supply relationship in patients with vasodilatory shock after cardiac surgery. METHODS: Eight mechanically ventilated patients, dependent on norepinephrine to maintain mean arterial pressure (MAP) > or = 60 mmHg because of septic/post-cardiotomy vasodilatory shock and multiple organ failure after cardiac surgery, were included. Vasopressin was sequentially infused at 1.2, 2.4 and 4.8 U/h for 30-min periods. Norepinephrine was simultaneously decreased to maintain MAP at 75 mmHg. At each infusion rate of vasopressin, data on systemic hemodynamics, jejunal mucosal perfusion, jejunal mucosal hematocrit and red blood cell velocity (laser Doppler flowmetry) as well as gastric-arterial pCO2 gradient (gastric tonometry) and splanchnic oxygen and lactate extraction (hepatic vein catheter) were obtained. RESULTS: The cardiac index, stroke volume index and systemic oxygen delivery decreased and systemic vascular resistance and systemic oxygen extraction increased significantly, while the heart rate or global oxygen consumption did not change with increasing vasopressin dose. Jejunal mucosal perfusion decreased and the arterial-gastric-mucosal pCO2 gradient increased, while splanchnic oxygen or lactate extraction or mixed venous-hepatic venous oxygen saturation gradient were not affected by increasing infusion rates of vasopressin. CONCLUSIONS: Infusion of low to moderate doses of vasopressin in patients with norepinephrine-dependent vasodilatory shock after cardiac surgery induces an intestinal and gastric mucosal vasoconstriction.
  •  
48.
  • Nygren, Andreas, 1967, et al. (författare)
  • Vasopressors and intestinal mucosal perfusion after cardiac surgery: Norepinephrine vs. phenylephrine.
  • 2006
  • Ingår i: Critical care medicine. - 0090-3493. ; 34:3, s. 722-9
  • Tidskriftsartikel (refereegranskat)abstract
    • OBJECTIVES: To evaluate the potential differential effects of norepinephrine, an alpha1-, beta1-, and beta2-receptor agonist, to the alpha1-agonist phenylephrine on jejunal mucosal perfusion, gastric-arterial PCO2 gradient, and the global splanchnic oxygen demand-supply relationship after cardiac surgery. DESIGN: A randomized, prospective, interventional crossover study. SETTING: A university cardiothoracic intensive care unit. PATIENTS: Ten patients were studied during propofol sedation and mechanical ventilation after uncomplicated coronary artery bypass surgery. INTERVENTIONS: Each patient received randomly and sequentially norepinephrine (0.052+/-0.009 microg/kg/min) and phenylephrine (0.50+/-0.22 microg/kg/min) to increase mean arterial blood pressure by 30%. MEASUREMENTS AND MAIN RESULTS: Data on jejunal mucosal perfusion, jejunal mucosal hematocrit, and red blood cell velocity (laser Doppler flowmetry) as well as gastric-arterial Pco2 gradient (tonometry) and splanchnic oxygen extraction were obtained before (control) and during a 30-min drug infusion period after the target mean arterial blood pressure was reached. The procedure was sequentially repeated for the second vasopressor. Both drugs induced a 40-46% increase in systemic vascular resistance with no change in cardiac index. Neither jejunal mucosal perfusion, jejunal mucosal hematocrit, red blood cell velocity, nor gastric-arterial Pco2 gradient was affected by any of the vasopressors. Splanchnic oxygen extraction increased from 38.2% to 43.1% (p<.001) with norepinephrine and from 39.3% to 47.5% (p<.001) with phenylephrine. This increase was significantly more pronounced with phenylephrine compared with norepinephrine (p<.05). Mixed venous-hepatic vein oxygen saturation gradient increased with both drugs (p<.01), and the increase was more pronounced with phenylephrine (p<.05). Splanchnic lactate extraction was not significantly affected by any of the vasopressors. CONCLUSIONS: Phenylephrine induced a more pronounced global alpha1-mediated splanchnic vasoconstriction compared with norepinephrine. Neither of the vasoconstrictors impaired perfusion of the gastrointestinal mucosa in postcardiac surgery patients. The lack of norepinephrine-induced, alpha1-mediated impairment of gastrointestinal perfusion is not explained by a beta2-mediated counteractive vasodilation but instead by possible mucosal autoregulatory escape.
  •  
49.
  • Nygren, Christer, et al. (författare)
  • ICT enabled business model innovation to support servitization in global industrial companies
  • 2013
  • Konferensbidrag (refereegranskat)abstract
    • Servitization in industrial companies to escape the “commodity trap” can be enhanced by business model innovation (BMI) in order to systemically focus on the firm ?s value proposition, its organization of (co-) production as well as capturing of value in revenue mechanisms (Amit & Zott, 2012; Chesborough, 2010). ICT oriented developments like cloud, big data, internet of thing, smart installed base here offer potentials to take advantage and develop the information base of products, processes, utilization and customer behavior and needs into new and more complex offerings (LaValle et al., 2011). The purpose of the paper is to analyze the enablers and barriers for innovation in ICT enabled business models to ease and accelerate the journey towards service business development in global industrial companies. The research is done through a literature review on research and BMI cases, and a process oriented case study of emerging developments in a global industrial company. The research result is identification and synthesis of enabling factors and barriers in servitization through ICT supported BMI. Enabling factors are related to information and information processing potentials and organizational capabilities to increase service content of offerings, while barriers are e.g. internal integration and competence as well as customer trust, information confidentiality as well as willingness to engage in more close, service oriented and co- creative business relationships. The result will be input to ongoing action research collaboration with industrial companies in terms of research agenda as well as practical insights for BMI efforts.
  •  
50.
  • Nygren, Erik, 1976 (författare)
  • A mouse model for direct evaluation of cholera vaccines
  • 2009
  • Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
    • Cholera continues to be an important cause of morbidity and mortality in large parts of the developing world and is a significant negative factor for economic development. Vibrio cholerae bacteria of the O1 or O139 serogroup can cause disease due to their ability to colonize the intestine and produce an enterotoxin, cholera toxin (CT). An effective oral vaccine against V. cholerae O1 is available, whereas vaccine against O139 is lacking. Development and pre-clinical evaluation of cholera vaccines have been hampered by the fact that man is the only natural host for V. cholerae. Although various animal models have been described, there exists no convenient and inexpensive model that allows evaluation of vaccine-induced protection against a challenge infection. The main objective of this thesis was to develop a model that allows direct evaluation of the immunogenicity and protective efficacy of cholera vaccine candidates in conventional adult mice. Paper I demonstrates that strong serum and mucosal antibody responses to V. cholerae O1 or O139 lipopolysaccharide (LPS) can be induced in adult mice vaccinated intranasally or orally with either live or formalin-killed bacteria. Standardized intestinal IgA antibody responses estimated using extracts prepared from faecal pellets or from intestinal mucosa were found to correlate significantly, hence validating the use of the more convenient fecal pellets extracts for measuring gut mucosal antibody responses in vaccinated hosts. Paper II describes an adult mouse model for studying intestinal colonization by V. cholerae and associated immune responses. It was shown that oral pre-treatment of mice with streptomycin (Sm) allows intestinal colonization by Sm-resistant V. cholerae O1 or O139 bacteria, and that mice immunized with viable or inactivated V. cholerae as described in Paper I were comparatively refractory to colonization following infection/challenge with the immunizing strain, with protection resulting in accelerated clearance of the challenge organisms correlating inversely with the intestinal IgA anti-LPS response. In paper III this model was further used to evaluate immune responses and protection by orally administered live and killed O1 and O139 whole cell vaccines and the impact of co-administration of CT on the immunogenicity and protective effect. CT proved to be an effective adjuvant, markedly potentiating antibody responses and also increasing the protective effect against both serogroup homologous and heterologous challenge. The results presented in this thesis suggest that the new adult mouse model may be used to broaden our understanding of immune protection against V. cholerae infection, and thus be a useful tool in the pre-clinical evaluation of oral cholera vaccines.
  •  
Skapa referenser, mejla, bekava och länka
  • Resultat 1-50 av 74
Författare/redaktör
Nygren, Ingemar (7)
Nygren, Erik (5)
Nygren, Tord, 1936- (4)
Bornlid, Jan Erik, 1 ... (4)
Nygren, Erik, 1897- (4)
Blomqvist, Lars Erik ... (2)
visa fler...
Gomer, Eva, 1931- (2)
Sundberg, Lars Erik, ... (2)
Hedin, Nathan, 1880- ... (2)
Ejdestam, Julius, 19 ... (2)
Johansson, Sven-Erik ... (1)
Alfons, Harriet, 192 ... (1)
Nygren, Ingela (1)
Krumlinde, Lars, 194 ... (1)
Beckman, Erik, 1935- ... (1)
Sandin, Erik, 1933-1 ... (1)
Danielsson, Bror, 19 ... (1)
Martín, Carlos (1)
Updike, John (1)
Nordenskiöld, Adolf ... (1)
Broué, Pierre (1)
Brandinger, Rune, 19 ... (1)
Körberg, Ingvar, 192 ... (1)
Blomgren, Lars-Erik, ... (1)
Beukel, Erik (1)
Tawaststjerna, Erik, ... (1)
Jonsson, Bengt (1)
Hollnagel, Erik (1)
Westerholm, Peter, 1 ... (1)
Olofsson, Birgitta. (1)
Moberg, Erik, 1937- (1)
Nygren, Pär, 1948- (1)
Söderblom, Staffan (1)
Nygren, Lennart (1)
Nygren, Christer (1)
Nilsson, Jan, 1948- (1)
Rosin, Björn-Erik, 1 ... (1)
Nygren, Thomas (1)
Nygren, Sven, 1950- (1)
Renås, Rune, 1923- (1)
Eriksson, Lars-Erik (1)
Ring, Börge (1)
Borg, Karl-Erik, 191 ... (1)
Danielsson, Bror, 19 ... (1)
Mossberg, Lennart, 1 ... (1)
Änggård, Erik, 1934- (1)
Nygren, Peter (1)
Olsson, Erik (1)
Sandberg, Erik (1)
Nygren, Hans (1)
visa färre...
Språk
Engelska (65)
Svenska (8)
Odefinierat språk (1)
Forskningsämne (UKÄ/SCB)
Medicin och hälsovetenskap (24)
Naturvetenskap (17)
Teknik (11)
Samhällsvetenskap (8)
Lantbruksvetenskap (1)
Humaniora (1)

År

Kungliga biblioteket hanterar dina personuppgifter i enlighet med EU:s dataskyddsförordning (2018), GDPR. Läs mer om hur det funkar här.
Så här hanterar KB dina uppgifter vid användning av denna tjänst.

 
pil uppåt Stäng

Kopiera och spara länken för att återkomma till aktuell vy