| 51. |
- Evander, Mikael, et al.
(författare)
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Acoustic Trapping: System Design, Optimization and Applications
- 2006
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Ingår i: Proceedings of the sixth Micro Structure Workshop. ; 1, s. 33-33
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Konferensbidrag (refereegranskat)abstract
- Manipulation, separation and trapping of particles and cells are very important tools in today's bioanalytical and medical field. The acoustic no-contact trapping method presented at earlier MSW 2004 provides a flexible platform for performing cell and particle assays in a perfusion-based microsystem. To further develop the system microfabricated glass channels are now used, resulting in shorter fabrication times and a very inert channel material. The fluidic design has been revised to minimise the risks of leaking and hydrodynamic focusing has been incorporated to ensure a high trapping efficiency. A change of piezoelectric materials has resulted in less thermal losses in the material, higher reproducibility and shorter manufacturing time. The trapping force was estimated by calculating the fluid force exerted on a single particle levitated in the standing wave as a reference. The temperature increase due to the losses in the transducer was measured using a fluorescent dye, indicating a maximum temperature increase of 10 degrees Celsius. Live cells have been trapped and shown to be viable while still suspended in the standing wave, thus making it possible to do on-line studies on, for example, drug response of cell populations.
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| 52. |
- Evander, Mikael, et al.
(författare)
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Noninvasive acoustic cell trapping in a microfluidic perfusion system for online bioassays
- 2007
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Ingår i: Analytical Chemistry. - : American Chemical Society (ACS). - 0003-2700 .- 1520-6882. ; 79:7, s. 2984-2991
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Tidskriftsartikel (refereegranskat)abstract
- Techniques for manipulating, separating, and trapping particles and cells are highly desired in today's bioanalytical and biomedical field. The microfluidic chip-based acoustic noncontact trapping method earlier developed within the group now provides a flexible platform for performing cell- and particle-based assays in continuous flow microsystems. An acoustic standing wave is generated in etched glass channels (600x61 microm2) by miniature ultrasonic transducers (550x550x200 microm3). Particles or cells passing the transducer will be retained and levitated in the center of the channel without any contact with the channel walls. The maximum trapping force was calculated to be 430+/-135 pN by measuring the drag force exerted on a single particle levitated in the standing wave. The temperature increase in the channel was characterized by fluorescence measurements using rhodamine B, and levels of moderate temperature increase were noted. Neural stem cells were acoustically trapped and shown to be viable after 15 min. Further evidence of the mild cell handling conditions was demonstrated as yeast cells were successfully cultured for 6 h in the acoustic trap while being perfused by the cell medium at a flowrate of 1 microL/min. The acoustic microchip method facilitates trapping of single cells as well as larger cell clusters. The noncontact mode of cell handling is especially important when studies on nonadherent cells are performed, e.g., stem cells, yeast cells, or blood cells, as mechanical stress and surface interaction are minimized. The demonstrated acoustic trapping of cells and particles enables cell- or particle-based bioassays to be performed in a continuous flow format.
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| 53. |
- Evander, Mikael, et al.
(författare)
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Versatile microchip utilising ultrasonic standing waves
- 2005
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Ingår i: IFMBE Proceedings 2005. ; , s. 123-124
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Konferensbidrag (refereegranskat)abstract
- This paper presents the concept and initial work on a microfluidic platform for bead-based analysis of biological sample. The core technology in this project is ultrasonic manipulation and trapping of particle in array configurations by means of acoustic forces. The platform is ultimately aimed for parallel multistep bioassays performed on biochemically activated microbeads (or particles) using submicrolitre sample volumes. A first prototype with three individually controlled particle trapping sites has been developed and evaluated. Standing ultrasonic waves were generated across a microfluidic channel by integrated PZT ultrasonic microtransducers. Particles in a fluid passing a transducer were drawn to pressure minima in the acoustic field, thereby being trapped and confined laterally over the transducer. It is anticipated that acoustic trapping using integrated transducers can be exploited in miniaturised total chemical analysis systems (µTAS), where e.g. microbeads with immobilised antibodies can be trapped in arrays and subjected to minute amounts of sample followed by a reaction, detected using fluorescence. Preliminary results indicate that the platform is capable of handling live cells as well as microbeads. A first model bioassay with detection of fluorescein marked avidin binding to trapped biotin beads has been evaluated.
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| 54. |
- Fahnestock, Jesse, 1974-, et al.
(författare)
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RISEnergy: Roadmaps for energy innovation in Sweden through 2030
- 2016
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- RISE Research Institutes of Sweden is a group of research and technology organisations. RISE is a leading innovation partner working global cooperation with academia, enterprise and society to create value, growth and competitiveness through research excellence and innovation.In the area of Energy, RISE has developed innovation Roadmaps covering:Energy Efficient TransportElectric Power SystemEnergy Efficient and Smart BuildingsSustainable Thermal ProcessesEfficient Energy Use in IndustryDecarbonisation of Basic IndustriesThese Roadmaps describe development pathways for technologies, non-technical elements (market design, user behaviours, policies, etc.) and key actors that deliver on a plausible, desirable vision for each respective innovation area in 2030. These Roadmaps are intended to support RISE’s strategic planning and development, but should be relevant reading for anyone interested in energy innovation in Sweden.
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| 55. |
- Fanidi, Anouar, et al.
(författare)
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A prospective study of one-carbon metabolism biomarkers and cancer of the head and neck and esophagus
- 2015
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Ingår i: International Journal of Cancer. - : Wiley-Blackwell. - 0020-7136 .- 1097-0215. ; 136:4, s. 915-927
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Tidskriftsartikel (refereegranskat)abstract
- Experimental and epidemiological data suggest that factors of one-carbon metabolism are important in the pathogenesis of several cancers, but prospective data on head and neck cancer (HNC) and esophagus cancer are limited. The European Prospective Investigation into Cancer and Nutrition (EPIC) study recruited 385,747 participants from 10 countries who donated a blood sample. The current study included 516 cancer cases of the head and neck and esophagus and 516 individually matched controls. Plasma levels of vitamins B2, B6, B9 (folate), B12, and methionine and homocysteine were measured in pre-diagnostic plasma samples and analyzed in relation to HNC and esophagus cancer risk, as well as post-diagnosis all-cause mortality. After controlling for risk factors, study participants with higher levels of homocysteine had elevated risk of HNC, the odds ratio (OR) in conditional analysis when comparing the top and bottom quartiles of homocysteine [ORQ4vs. Q1] being 2.13 (95% confidence interval [95% CI] 1.13-4.00, p for trend 0.009). A slight decrease in HNC risk was also seen among subjects with higher levels of folate (ORQ4vs. Q1 0.63, 95% CI 0.35-1.16, p for trend 0.02). Subgroup analyses by anatomical sub-site indicated particularly strong associations with circulating homocysteine for oral cavity and gum cancer (p for trend 8 x 10(-4)), as well as for oropharynx cancer (p for trend 0.008). Plasma concentrations of the other investigated biomarkers did not display any clear association with risk or survival. In conclusion, study participants with elevated circulating levels of homocysteine had increased risk of developing squamous cell carcinoma of the head and neck. What's new? One-carbon metabolism (OCM) involves the transfer of a carbon unit from methyl donor nutrients to molecules involved in the synthesis and methylation of DNA. As a result, dietary imbalances or deficiencies in nutrients crucial for OCM may affect DNA replication, repair, and regulation, potentially facilitating cancer development. This analysis of circulating levels of OCM nutrients in head and neck cancer and esophageal cancer patients and matched controls reveals an association between elevated levels of the amino acid homocysteine and increased risk of squamous cell carcinoma of the head and neck. Risk was decreased slightly by elevated folate levels.
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| 56. |
- Fanidi, Anouar, et al.
(författare)
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Circulating Folate, Vitamin B6, and Methionine in Relation to Lung Cancer Risk in the Lung Cancer Cohort Consortium (LC3)
- 2018
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Ingår i: Journal of the National Cancer Institute. - : Oxford University Press. - 0027-8874 .- 1460-2105. ; 110:1
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Tidskriftsartikel (refereegranskat)abstract
- Background: Circulating concentrations of B vitamins and factors related to one-carbon metabolism have been found to be strongly inversely associated with lung cancer risk in the European Prospective Investigation into Cancer and Nutrition (EPIC) study. The extent to which these associations are present in other study populations is unknown.Methods: Within 20 prospective cohorts from the National Cancer Institute Cohort Consortium, a nested case-control study was designed including 5364 incident lung cancer case patients and 5364 control subjects who were individually matched to case patients by age, sex, cohort, and smoking status. Centralized biochemical analyses were performed to measure circulating concentrations of vitamin B6, folate, and methionine, as well as cotinine as an indicator of recent tobacco exposure. The association between these biomarkers and lung cancer risk was evaluated using conditional logistic regression models.Results: Participants with higher circulating concentrations of vitamin B6 and folate had a modestly decreased risk of lung cancer risk overall, the odds ratios when comparing the top and bottom fourths (OR 4vs1 ) being 0.88 (95% confidence interval [CI] = 0.78 to 1.00) and 0.86 (95% CI = 0.74 to 0.99), respectively. We found stronger associations among men (vitamin B6: OR 4vs1 = 0.74, 95% CI = 0.62 to 0.89; folate: OR 4vs1 = 0.75, 95% CI = 0.61 to 0.93) and ever smokers (vitamin B6: OR 4vs1 = 0.78, 95% CI = 0.67 to 0.91; folate: OR 4vs1 = 0.87, 95% CI = 0.73 to 1.03). We further noted that the association of folate was restricted to Europe/Australia and Asia, whereas no clear association was observed for the United States. Circulating concentrations of methionine were not associated with lung cancer risk overall or in important subgroups.Conclusions: Although confounding by tobacco exposure or reverse causation cannot be ruled out, these study results are compatible with a small decrease in lung cancer risk in ever smokers who avoid low concentrations of circulating folate and vitamin B6.
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| 57. |
- Fanidi, Anouar, et al.
(författare)
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Is high vitamin B12 status a cause of lung cancer?
- 2019
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Ingår i: International Journal of Cancer. - : John Wiley & Sons. - 0020-7136 .- 1097-0215. ; 145:6, s. 1499-1503
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Tidskriftsartikel (refereegranskat)abstract
- Vitamin B supplementation can have side effects for human health, including cancer risk. We aimed to elucidate the role of vitamin B12 in lung cancer etiology via direct measurements of pre‐diagnostic circulating vitamin B12 concentrations in a nested case–control study, complemented with a Mendelian randomization (MR) approach in an independent case–control sample. We used pre‐diagnostic biomarker data from 5183 case–control pairs nested within 20 prospective cohorts, and genetic data from 29,266 cases and 56,450 controls. Exposures included directly measured circulating vitamin B12 in pre‐diagnostic blood samples from the nested case–control study, and 8 single nucleotide polymorphisms associated with vitamin B12 concentrations in the MR study. Our main outcome of interest was increased risk for lung cancer, overall and by histological subtype, per increase in circulating vitamin B12 concentrations. We found circulating vitamin B12 to be positively associated with overall lung cancer risk in a dose response fashion (odds ratio for a doubling in B12 [ORlog2B12] = 1.15, 95% confidence interval (95%CI) = 1.06–1.25). The MR analysis based on 8 genetic variants also indicated that genetically determined higher vitamin B12 concentrations were positively associated with overall lung cancer risk (OR per 150 pmol/L standard deviation increase in B12 [ORSD] = 1.08, 95%CI = 1.00–1.16). Considering the consistency of these two independent and complementary analyses, these findings support the hypothesis that high vitamin B12 status increases the risk of lung cancer.
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| 58. |
- Fasanelli, Francesca, et al.
(författare)
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Hypomethylation of smoking-related genes is associated with future lung cancer in four prospective cohorts
- 2015
-
Ingår i: Nature Communications. - : Nature Publishing Group. - 2041-1723. ; 6
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Tidskriftsartikel (refereegranskat)abstract
- DNA hypomethylation in certain genes is associated with tobacco exposure but it is unknown whether these methylation changes translate into increased lung cancer risk. In an epigenome-wide study of DNA from pre-diagnostic blood samples from 132 case–control pairs in the NOWAC cohort, we observe that the most significant associations with lung cancer risk are for cg05575921 in AHRR (OR for 1 s.d.=0.37, 95% CI: 0.31–0.54, P-value=3.3 × 10−11) and cg03636183 in F2RL3 (OR for 1 s.d.=0.40, 95% CI: 0.31–0.56, P-value=3.9 × 10−10), previously shown to be strongly hypomethylated in smokers. These associations remain significant after adjustment for smoking and are confirmed in additional 664 case–control pairs tightly matched for smoking from the MCCS, NSHDS and EPIC HD cohorts. The replication and mediation analyses suggest that residual confounding is unlikely to explain the observed associations and that hypomethylation of these CpG sites may mediate the effect of tobacco on lung cancer risk.
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| 59. |
- Feng, Xiaoshuang, et al.
(författare)
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Evaluation of pre-diagnostic blood protein measurements for predicting survival after lung cancer diagnosis
- 2023
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Ingår i: EBioMedicine. - : Elsevier. - 2352-3964. ; 92
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Tidskriftsartikel (refereegranskat)abstract
- Background: To evaluate whether circulating proteins are associated with survival after lung cancer diagnosis, and whether they can improve prediction of prognosis.Methods: We measured up to 1159 proteins in blood samples from 708 participants in 6 cohorts. Samples were collected within 3 years prior to lung cancer diagnosis. We used Cox proportional hazards models to identify proteins associated with overall mortality after lung cancer diagnosis. To evaluate model performance, we used a round-robin approach in which models were fit in 5 cohorts and evaluated in the 6th cohort. Specifically, we fit a model including 5 proteins and clinical parameters and compared its performance with clinical parameters only.Findings: There were 86 proteins nominally associated with mortality (p < 0.05), but only CDCP1 remained statistically significant after accounting for multiple testing (hazard ratio per standard deviation: 1.19, 95% CI: 1.10–1.30, unadjusted p = 0.00004). The external C-index for the protein-based model was 0.63 (95% CI: 0.61–0.66), compared with 0.62 (95% CI: 0.59–0.64) for the model with clinical parameters only. Inclusion of proteins did not provide a statistically significant improvement in discrimination (C-index difference: 0.015, 95% CI: −0.003 to 0.035).Interpretation: Blood proteins measured within 3 years prior to lung cancer diagnosis were not strongly associated with lung cancer survival, nor did they importantly improve prediction of prognosis beyond clinical information.
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| 60. |
- Feng, Xiaoshuang, et al.
(författare)
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Lung cancer risk discrimination of prediagnostic proteomics measurements compared with existing prediction tools
- 2023
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Ingår i: Journal of the National Cancer Institute. - : Oxford University Press. - 0027-8874 .- 1460-2105. ; 115:9, s. 1050-1059
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: We sought to develop a proteomics-based risk model for lung cancer and evaluate its risk-discriminatory performance in comparison with a smoking-based risk model (PLCOm2012) and a commercially available autoantibody biomarker test.METHODS: We designed a case-control study nested in 6 prospective cohorts, including 624 lung cancer participants who donated blood samples at most 3 years prior to lung cancer diagnosis and 624 smoking-matched cancer free participants who were assayed for 302 proteins. We used 470 case-control pairs from 4 cohorts to select proteins and train a protein-based risk model. We subsequently used 154 case-control pairs from 2 cohorts to compare the risk-discriminatory performance of the protein-based model with that of the Early Cancer Detection Test (EarlyCDT)-Lung and the PLCOm2012 model using receiver operating characteristics analysis and by estimating models' sensitivity. All tests were 2-sided.RESULTS: The area under the curve for the protein-based risk model in the validation sample was 0.75 (95% confidence interval [CI] = 0.70 to 0.81) compared with 0.64 (95% CI = 0.57 to 0.70) for the PLCOm2012 model (Pdifference = .001). The EarlyCDT-Lung had a sensitivity of 14% (95% CI = 8.2% to 19%) and a specificity of 86% (95% CI = 81% to 92%) for incident lung cancer. At the same specificity of 86%, the sensitivity for the protein-based risk model was estimated at 49% (95% CI = 41% to 57%) and 30% (95% CI = 23% to 37%) for the PLCOm2012 model.CONCLUSION: Circulating proteins showed promise in predicting incident lung cancer and outperformed a standard risk prediction model and the commercialized EarlyCDT-Lung.
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