SwePub
Sök i SwePub databas

  Utökad sökning

Träfflista för sökning "LAR1:uu ;pers:(Larsson Rolf)"

Sökning: LAR1:uu > Larsson Rolf

  • Resultat 1-10 av 363
Sortera/gruppera träfflistan
   
NumreringReferensOmslagsbildHitta
1.
  •  
2.
  • Abadir, Karim M., et al. (författare)
  • Biases of correlograms and of AR representations of stationary series
  • 2012
  • Ingår i: Journal of Time Series Econometrics. - : Walter de Gruyter GmbH. - 1941-1928 .- 1941-1928. ; 4:1
  • Tidskriftsartikel (refereegranskat)abstract
    • We derive the relation between the biases of correlograms and of estimates of auto-regressive AR(k) representations of stationary series, and we illustrate it with a simple AR example. The new relation allows for k to vary with the sample size, which is a representation that can be used for most stationary processes. As a result, the biases of the estimators of such processes can now be quantified explicitly and in a unified way.
  •  
3.
  • Aftab, Obaid, 1984-, et al. (författare)
  • Detection of cell aggregation and altered cell viability by automated label-free video microscopy : A promising alternative to endpoint viability assays in high throughput screening
  • 2015
  • Ingår i: Journal of Biomolecular Screening. - : Elsevier BV. - 1087-0571 .- 1552-454X. ; 20:3, s. 372-381
  • Tidskriftsartikel (refereegranskat)abstract
    • Automated phase-contrast video microscopy now makes it feasible to monitor a high-throughput (HT) screening experiment in a 384-well microtiter plate format by collecting one time-lapse video per well. Being a very cost-effective and label-free monitoring method, its potential as an alternative to cell viability assays was evaluated. Three simple morphology feature extraction and comparison algorithms were developed and implemented for analysis of differentially time-evolving morphologies (DTEMs) monitored in phase-contrast microscopy videos. The most promising layout, pixel histogram hierarchy comparison (PHHC), was able to detect several compounds that did not induce any significant change in cell viability, but made the cell population appear as spheroidal cell aggregates. According to recent reports, all these compounds seem to be involved in inhibition of platelet-derived growth factor receptor (PDGFR) signaling. Thus, automated quantification of DTEM (AQDTEM) holds strong promise as an alternative or complement to viability assays in HT in vitro screening of chemical compounds.
  •  
4.
  • Aftab, Obaid, 1984-, et al. (författare)
  • Label-free detection and dynamic monitoring of drug-induced intracellular vesicle formation enabled using a 2-dimensional matched filter
  • 2014
  • Ingår i: Autophagy. - : Informa UK Limited. - 1554-8627 .- 1554-8635. ; 10:1, s. 57-69
  • Tidskriftsartikel (refereegranskat)abstract
    • Analysis of vesicle formation and degradation is a central issue in autophagy research and microscopy imaging is revolutionizing the study of such dynamic events inside living cells. A limiting factor is the need for labeling techniques that are labor intensive, expensive, and not always completely reliable. To enable label-free analyses we introduced a generic computational algorithm, the label-free vesicle detector (LFVD), which relies on a matched filter designed to identify circular vesicles within cells using only phase-contrast microscopy images. First, the usefulness of the LFVD is illustrated by presenting successful detections of autophagy modulating drugs found by analyzing the human colorectal carcinoma cell line HCT116 exposed to each substance among 1266 pharmacologically active compounds. Some top hits were characterized with respect to their activity as autophagy modulators using independent in vitro labeling of acidic organelles, detection of LC3-II protein, and analysis of the autophagic flux. Selected detection results for 2 additional cell lines (DLD1 and RKO) demonstrate the generality of the method. In a second experiment, label-free monitoring of dose-dependent vesicle formation kinetics is demonstrated by recorded detection of vesicles over time at different drug concentrations. In conclusion, label-free detection and dynamic monitoring of vesicle formation during autophagy is enabled using the LFVD approach introduced.
  •  
5.
  • Aftab, Obaid, 1984-, et al. (författare)
  • Label free high throughput screening for apoptosis inducing chemicals using time-lapse microscopy signal processing
  • 2014
  • Ingår i: Apoptosis (London). - : Springer Science and Business Media LLC. - 1360-8185 .- 1573-675X. ; 19:9, s. 1411-1418
  • Tidskriftsartikel (refereegranskat)abstract
    • Label free time-lapse microscopy has opened a new avenue to the study of time evolving events in living cells. When combined with automated image analysis it provides a powerful tool that enables automated large-scale spatiotemporal quantification at the cell population level. Very few attempts, however, have been reported regarding the design of image analysis algorithms dedicated to the detection of apoptotic cells in such time-lapse microscopy images. In particular, none of the reported attempts is based on sufficiently fast signal processing algorithms to enable large-scale detection of apoptosis within hours/days without access to high-end computers. Here we show that it is indeed possible to successfully detect chemically induced apoptosis by applying a two-dimensional linear matched filter tailored to the detection of objects with the typical features of an apoptotic cell in phase-contrast images. First a set of recorded computational detections of apoptosis was validated by comparison with apoptosis specific caspase activity readouts obtained via a fluorescence based assay. Then a large screen encompassing 2,866 drug like compounds was performed using the human colorectal carcinoma cell line HCT116. In addition to many well known inducers (positive controls) the screening resulted in the detection of two compounds here reported for the first time to induce apoptosis.
  •  
6.
  • Aftab, Obaid, 1984-, et al. (författare)
  • Label free quantification of time evolving morphologies using time-lapse video microscopy enables identity control of cell lines and discovery of chemically induced differential activity in iso-genic cell line pairs
  • 2015
  • Ingår i: Chemometrics and Intelligent Laboratory Systems. - 0169-7439 .- 1873-3239. ; 141, s. 24-32
  • Tidskriftsartikel (refereegranskat)abstract
    • Label free time-lapse video microscopy based monitoring of time evolving cell population morphology has potential to offer a simple and cost effective method for identity control of cell lines. Such morphology monitoring also has potential to offer discovery of chemically induced differential changes between pairs of cell lines of interest, for example where one in a pair of cell lines is normal/sensitive and the other malignant/resistant. A new simple algorithm, pixel histogram hierarchy comparison (PHHC), for comparison of time evolving morphologies (TEM) in phase contrast time-lapse microscopy movies was applied to a set of 10 different cell lines and three different iso-genic colon cancer cell line pairs, each pair being genetically identical except for a single mutation. PHHC quantifies differences in morphology by comparing pixel histogram intensities at six different resolutions. Unsupervised clustering and machine learning based classification methods were found to accurately identify cell lines, including their respective iso-genic variants, through time-evolving morphology. Using this experimental setting, drugs with differential activity in iso-genic cell line pairs were likewise identified. Thus, this is a cost effective and expedient alternative to conventional molecular profiling techniques and might be useful as part of the quality control in research incorporating cell line models, e.g. in any cell/tumor biology or toxicology project involving drug/agent differential activity in pairs of cell line models.
  •  
7.
  • Ahlin, Gustav, et al. (författare)
  • Structural requirements for drug inhibition of the liver specific human organic cation transport protein 1
  • 2008
  • Ingår i: Journal of Medicinal Chemistry. - : American Chemical Society (ACS). - 0022-2623 .- 1520-4804. ; 51:19, s. 5932-5942
  • Tidskriftsartikel (refereegranskat)abstract
    • The liver-specific organic cation transport protein (OCT1; SLC22A1) transports several cationic drugs including the antidiabetic drug metformin and the anticancer agents oxaliplatin and imatinib. In this study, we explored the chemical space of registered oral drugs with the aim of studying the inhibition pattern of OCT1 and of developing predictive computational models of OCT1 inhibition. In total, 191 structurally diverse compounds were examined in HEK293-OCT1 cells. The assay identified 47 novel inhibitors and confirmed 15 previously known inhibitors. The enrichment of OCT1 inhibitors was seen in several drug classes including antidepressants. High lipophilicity and a positive net charge were found to be the key physicochemical properties for OCT1 inhibition, whereas a high molecular dipole moment and many hydrogen bonds were negatively correlated to OCT1 inhibition. The data were used to generate OPLS-DA models for OCT1 inhibitors; the final model correctly predicted 82% of the inhibitors and 88% of the noninhibitors of the test set.
  •  
8.
  • Alvarsson, Jonathan, et al. (författare)
  • Brunn : an open source laboratory information system for microplates with a graphical plate layout design process
  • 2011
  • Ingår i: BMC Bioinformatics. - : Springer Science and Business Media LLC. - 1471-2105. ; 12:1
  • Tidskriftsartikel (refereegranskat)abstract
    • Background:Compound profiling and drug screening generates large amounts of data and is generally based on microplate assays. Current information systems used for handling this are mainly commercial, closed source, expensive, and heavyweight and there is a need for a flexible lightweight open system for handling plate design, and validation and preparation of data.Results:A Bioclipse plugin consisting of a client part and a relational database was constructed. A multiple-step plate layout point-and-click interface was implemented inside Bioclipse. The system contains a data validation step, where outliers can be removed, and finally a plate report with all relevant calculated data, including dose-response curves.Conclusions:Brunn is capable of handling the data from microplate assays. It can create dose-response curves and calculate IC50 values. Using a system of this sort facilitates work in the laboratory. Being able to reuse already constructed plates and plate layouts by starting out from an earlier step in the plate layout design process saves time and cuts down on error sources.
  •  
9.
  • Amiri, Saeid, 1976- (författare)
  • On the Application of the Bootstrap : Coefficient of Variation, Contingency Table, Information Theory and Ranked Set Sampling
  • 2011
  • Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
    • This thesis deals with the bootstrap method. Three decades after the seminal paper by Bradly Efron, still the horizons of this method need more exploration. The research presented herein has stepped into different fields of statistics where the bootstrap method can be utilized as a fundamental statistical tool in almost any application. The thesis considers various statistical problems, which is explained briefly below. Bootstrap method: A comparison of the parametric and the nonparametric bootstrap of variance is presented. The bootstrap of ranked set sampling is dealt with, as well as the wealth of theories and applications on the RSS bootstrap that exist nowadays. Moreover, the performance of RSS in resampling is explored. Furthermore, the application of the bootstrap method in the inference of contingency table test is studied. Coefficient of variation: This part shows the capacity of the bootstrap for inferring the coefficient of variation, a task which the asymptotic method does not perform very well. Information theory: There are few works on the study of information theory, especially on the inference of entropy. The papers included in this thesis try to achieve the inference of entropy using the bootstrap method. 
  •  
10.
  • Andersson, Claes, et al. (författare)
  • Assessment in vitro of interactions between anti-cancer drugs and noncancer drugs commonly used by cancer patients
  • 2023
  • Ingår i: Anti-Cancer Drugs. - : Lippincott Williams & Wilkins. - 0959-4973 .- 1473-5741. ; 34:1, s. 92-102
  • Tidskriftsartikel (refereegranskat)abstract
    • Cancer patients often suffer from cancer symptoms, treatment complications and concomitant diseases and are, therefore, often treated with several drugs in addition to anticancer drugs. Whether such drugs, here denoted as 'concomitant drugs', have anticancer effects or interact at the tumor cell level with the anticancer drugs is not very well known. The cytotoxic effects of nine concomitant drugs and their interactions with five anti-cancer drugs commonly used for the treatment of colorectal cancer were screened over broad ranges of drug concentrations in vitro in the human colon cancer cell line HCT116wt. Seven additional tyrosine kinase inhibitors were included to further evaluate key findings as were primary cultures of tumor cells from patients with colorectal cancer. Cytotoxic effects were evaluated using the fluorometric microculture cytotoxicity assay (FMCA) and interaction analysis was based on Bliss independent interaction analysis. Simvastatin and loperamide, included here as an opioid agonists, were found to have cytotoxic effects on their own at reasonably low concentrations whereas betamethasone, enalapril, ibuprofen, metformin, metoclopramide, metoprolol and paracetamol were inactive also at very high concentrations. Drug interactions ranged from antagonistic to synergistic over the concentrations tested with a more homogenous pattern of synergy between simvastatin and protein kinase inhibitors in HCT116wt cells. Commonly used concomitant drugs are mostly neither expected to have anticancer effects nor to interact significantly with anticancer drugs frequently used for the treatment of colorectal cancer.
  •  
Skapa referenser, mejla, bekava och länka
  • Resultat 1-10 av 363
Typ av publikation
tidskriftsartikel (292)
annan publikation (31)
doktorsavhandling (31)
licentiatavhandling (3)
rapport (2)
forskningsöversikt (2)
visa fler...
bok (1)
bokkapitel (1)
visa färre...
Typ av innehåll
refereegranskat (279)
övrigt vetenskapligt/konstnärligt (84)
Författare/redaktör
Nygren, Peter (130)
Fryknäs, Mårten (77)
Gullbo, Joachim (62)
Lindhagen, Elin (32)
Rickardson, Linda (29)
visa fler...
Jarvius, Malin (26)
Linder, Stig (22)
Andersson, Claes (21)
Wickström, Malin (21)
Lövborg, Henrik (21)
Höglund, Martin (19)
Nilsson, Bo (18)
Jonsson, Elin (18)
Gustafsson, Mats G. (16)
Dhar, Sumeer (16)
Åleskog, Anna (16)
Gustafsson, Mats (15)
Bohlin, Lars (15)
Senkowski, Wojciech (15)
Elgue, Graciela (13)
Larsson, Rolf, 1962- (13)
Isaksson, Anders (12)
Larsson, Rolf, Profe ... (12)
Karlsson, Mats O. (11)
Blom, Kristin (11)
Sanchez, Javier (11)
Korsgren, Olle (9)
Lewensohn, Rolf (9)
D'Arcy, Padraig (9)
Ekelund, Sara (9)
Larsson, Anders (8)
Zhang, Xiaonan (8)
Hassan, Saadia (8)
Berglund, Malin (8)
Lönnerholm, Gudmar (8)
Strese, Sara (8)
Karlsson, MO (7)
Forestier, Erik (7)
Nilsson Ekdahl, Kris ... (7)
Hammerling, Ulf (7)
Nilsson, Kenneth (7)
Öberg, Fredrik (7)
Selvin, Tove (7)
Eriksson, Anna (7)
Mahteme, Haile (7)
Hong, Jaan (7)
Brnjic, Slavica (7)
Claeson, Per (7)
Frost, Britt-Marie (7)
visa färre...
Lärosäte
Uppsala universitet (363)
Karolinska Institutet (49)
Umeå universitet (7)
Lunds universitet (4)
Sveriges Lantbruksuniversitet (4)
Göteborgs universitet (3)
visa fler...
Chalmers tekniska högskola (3)
Kungliga Tekniska Högskolan (2)
Stockholms universitet (2)
Linköpings universitet (2)
Linnéuniversitetet (2)
Gymnastik- och idrottshögskolan (1)
visa färre...
Språk
Engelska (331)
Odefinierat språk (31)
Svenska (1)
Forskningsämne (UKÄ/SCB)
Medicin och hälsovetenskap (124)
Naturvetenskap (46)
Samhällsvetenskap (7)
Teknik (4)
Lantbruksvetenskap (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