14421. |
- Nordlund Ekblom, Maria M, et al.
(författare)
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Concurrent EMG feedback acutely improves strength and muscle activation
- 2012
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Ingår i: European Journal of Applied Physiology. - : Springer Science and Business Media LLC. - 1439-6319 .- 1439-6327. ; 112:5, s. 1899-1905
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Tidskriftsartikel (refereegranskat)abstract
- The purpose of this study was to investigate the acute effects of electromyographic (EMG) feedback on muscle activation and strength during maximal voluntary concentric and eccentric muscle actions. 15 females performed two sets of three lengthening and three shortening maximal voluntary isokinetic knee extensions at 20A degrees A s(-1) over 60A degrees range of motion. After the first set, subjects were randomized to either a control group (n = 8) or a feedback group (n = 7). In the second set, the control group performed tasks identical to those in the first set, whereas the feedback group additionally received concurrent visual feedback of the EMGrms from Vastus Medialis (VM). Knee extensor strength and EMG activation of VM, Vastus lateralis (VL) and hamstrings (HAM) were measured during the MVCs. Analyses were performed separately in a 1 s preactivation phase, a 1 s initial movement phase and a 1 s late movement phase. EMG feedback was associated with significantly higher knee extensor strength in all phases (20.5% p < 0.05, 18.2% p < 0.001 and 19% p < 0.001, respectively) for the eccentric MVCs and in the preactivation phase (16.3%, p < 0.001) and initial movement phases (7.2%, p < 0.05) for concentric MVCs. EMG feedback from VM further improved activation in VM and HAM but not VL. These findings suggested that concurrent visual EMG feedback from VM could acutely enhance muscle strength and activation. Before recommending implementation of EMG feedback in resistance training paradigms, the feedback parameters needs to be optimized and its long-term effects needs to be scrutinized.
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14422. |
- Nordlund, Jessica, et al.
(författare)
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DNA methylation-based subtype prediction for pediatric acute lymphoblastic leukemia
- 2015
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Ingår i: Clinical Epigenetics. - : Springer Science and Business Media LLC. - 1868-7083 .- 1868-7075. ; 7
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Tidskriftsartikel (refereegranskat)abstract
- Background: We present a method that utilizes DNA methylation profiling for prediction of the cytogenetic subtypes of acute lymphoblastic leukemia (ALL) cells from pediatric ALL patients. The primary aim of our study was to improve risk stratification of ALL patients into treatment groups using DNA methylation as a complement to current diagnostic methods. A secondary aim was to gain insight into the functional role of DNA methylation in ALL. Results: We used the methylation status of similar to 450,000 CpG sites in 546 well-characterized patients with T-ALL or seven recurrent B-cell precursor ALL subtypes to design and validate sensitive and accurate DNA methylation classifiers. After repeated cross-validation, a final classifier was derived that consisted of only 246 CpG sites. The mean sensitivity and specificity of the classifier across the known subtypes was 0.90 and 0.99, respectively. We then used DNA methylation classification to screen for subtype membership of 210 patients with undefined karyotype (normal or no result) or non-recurrent cytogenetic aberrations('other' subtype). Nearly half (n = 106) of the patients lacking cytogenetic subgrouping displayed highly similar methylation profiles as the patients in the known recurrent groups. We verified the subtype of 20% of the newly classified patients by examination of diagnostic karyotypes, array-based copy number analysis, and detection of fusion genes by quantitative polymerase chain reaction (PCR) and RNA-sequencing (RNA-seq). Using RNA-seq data from ALL patients where cytogenetic subtype and DNA methylation classification did not agree, we discovered several novel fusion genes involving ETV6, RUNX1, and PAX5. Conclusions: Our findings indicate that DNA methylation profiling contributes to the clarification of the heterogeneity in cytogenetically undefined ALL patient groups and could be implemented as a complementary method for diagnosis of ALL. The results of our study provide clues to the origin and development of leukemic transformation. The methylation status of the CpG sites constituting the classifiers also highlight relevant biological characteristics in otherwise unclassified ALL patients.
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14423. |
- Nordlund, Jessica, et al.
(författare)
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Genome-wide signatures of differential DNA methylation in pediatric acute lymphoblastic leukemia
- 2013
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Ingår i: Genome Biology. - : Springer Science and Business Media LLC. - 1465-6906 .- 1474-760X. ; 14:9, s. r105-
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND:Although aberrant DNA methylation has been observed previously in acute lymphoblastic leukemia (ALL), the patterns of differential methylation have not been comprehensively determined in all subtypes of ALL on a genome-wide scale. The relationship between DNA methylation, cytogenetic background, drug resistance and relapse in ALL is poorly understood.RESULTS:We surveyed the DNA methylation levels of 435,941 CpG sites in samples from 764 children at diagnosis of ALL and from 27 children at relapse. This survey uncovered four characteristic methylation signatures. First, compared with control blood cells, the methylomes of ALL cells shared 9,406 predominantly hypermethylated CpG sites, independent of cytogenetic background. Second, each cytogenetic subtype of ALL displayed a unique set of hyper- and hypomethylated CpG sites. The CpG sites that constituted these two signatures differed in their functional genomic enrichment to regions with marks of active or repressed chromatin. Third, we identified subtype-specific differential methylation in promoter and enhancer regions that were strongly correlated with gene expression. Fourth, a set of 6,612 CpG sites was predominantly hypermethylated in ALL cells at relapse, compared with matched samples at diagnosis. Analysis of relapse-free survival identified CpG sites with subtype-specific differential methylation that divided the patients into different risk groups, depending on their methylation status.CONCLUSIONS:Our results suggest an important biological role for DNA methylation in the differences between ALL subtypes and in their clinical outcome after treatment.
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14424. |
- Nordlund, Åke, et al.
(författare)
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Improved ability of biological and previous caries multimarkers to predict caries disease as revealed by multivariate PLS modelling
- 2009
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Ingår i: BMC Oral Health. - : Springer Science and Business Media LLC. - 1472-6831. ; 9, s. 28-
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Dental caries is a chronic disease with plaque bacteria, diet and saliva modifying disease activity. Here we have used the PLS method to evaluate a multiplicity of such biological variables (n = 88) for ability to predict caries in a cross-sectional (baseline caries) and prospective (2-year caries development) setting. METHODS: Multivariate PLS modelling was used to associate the many biological variables with caries recorded in thirty 14-year-old children by measuring the numbers of incipient and manifest caries lesions at all surfaces. RESULTS: A wide but shallow gliding scale of one fifth caries promoting or protecting, and four fifths non-influential, variables occurred. The influential markers behaved in the order of plaque bacteria > diet > saliva, with previously known plaque bacteria/diet markers and a set of new protective diet markers. A differential variable patterning appeared for new versus progressing lesions. The influential biological multimarkers (n = 18) predicted baseline caries better (ROC area 0.96) than five markers (0.92) and a single lactobacilli marker (0.7) with sensitivity/specificity of 1.87, 1.78 and 1.13 at 1/3 of the subjects diagnosed sick, respectively. Moreover, biological multimarkers (n = 18) explained 2-year caries increment slightly better than reported before but predicted it poorly (ROC area 0.76). By contrast, multimarkers based on previous caries predicted alone (ROC area 0.88), or together with biological multimarkers (0.94), increment well with a sensitivity/specificity of 1.74 at 1/3 of the subjects diagnosed sick. CONCLUSION: Multimarkers behave better than single-to-five markers but future multimarker strategies will require systematic searches for improved saliva and plaque bacteria markers.
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14425. |
- Nordqvist, Ola, et al.
(författare)
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Assessing and achieving readiness to initiate HIV medication
- 2006
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Ingår i: Patient Education and Counseling. - : Elsevier BV. - 0738-3991 .- 1873-5134. ; 62:1, s. 21-30
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Tidskriftsartikel (refereegranskat)abstract
- ObjectiveTo summarise published HIV-specific research on readiness theories, factors influencing readiness, instruments to measure readiness and interventions to increase readiness for treatment.MethodsMedline and PsychInfo were searched until August 2004.ResultsTwo HIV-specific readiness theories were identified. Fear of side effects, emotions emerging from the diagnosis and lack of trust in the physician were some barriers to overcome in order to reach readiness. Of the three measurement instruments found, the index of readiness showed the most promise. Multi-step intervention programs to increase readiness for HIV treatment had been investigated.ConclusionReadiness instruments may be useful tools in clinical practice but the predictive validity of the instruments needs to be further established in the HIV-infected population.Practice implicationsReadiness instruments and practice placebo trials may serve as complements to routine care, since health care providers currently have no better than chance probability in identifying those patients who are ready to adhere.
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14426. |
- Nordstrom, H., et al.
(författare)
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DNA microarray technique for detection and identification of seven Flaviviruses pathogenic for man
- 2005
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Ingår i: Journal of Medical Virology. - New York : Wiley. - 0146-6615 .- 1096-9071. ; 77:4, s. 528-540
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Tidskriftsartikel (refereegranskat)abstract
- A flavivirus microarray was developed for detection and identification of yellow fever (YF), West Nile, Japanese encephalitis (JE), and the dengue 1-4 viruses, which are causing severe human disease all over the world. The microarray was based on 500-nucleotide probe fragments from five different parts of the seven viral genomes. A low-stringent amplification method targeting the corresponding regions of the viral genomic RNA was developed and combined with hybridization to the microarray for detection and identification. For distinction of the generated virus-specific fluorescence-patterns a fitting analysis procedure was adapted. The method was verified as functional for all seven flaviviruses and the strategy for the amplification, combined with the long probes, provided a high tolerance for smaller genetic variability, most suitable for these rapidly changing RNA viruses. A potentially high detection and identification capacity was proven on diverged strains of West Nile and dengue viruses. The lower limit for detection was equivalent, or better, when compared to routinely used RT-PCR methods. The performance of the method was verified on human patient samples containing dengue viruses, or normal human serum spiked with YF or JE viruses. The results demonstrated the ability of the flavivirus microarray to screen simultaneously a sample for several viruses in parallel, in combination with a good lower limit of detection.
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14427. |
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14428. |
- Nordström, Dan, et al.
(författare)
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Beneficial Effect of Interleukin 1 Inhibition with Anakinra in Adult-onset Still's Disease. An Open, Randomized, Multicenter Study
- 2012
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Ingår i: Journal of Rheumatology. - : The Journal of Rheumatology. - 0315-162X .- 1499-2752. ; 39:10, s. 2008-2011
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Tidskriftsartikel (refereegranskat)abstract
- Objective. To study the efficacy of anakinra versus disease-modifying antirheumatic drugs (DMARD) in refractory adult-onset Still's disease (AOSD). Methods. In a 24-week study, 22 patients with AOSD taking prednisolone >= 10 mg/day received anakinra (n = 12) or DMARD (n = 10). The primary endpoint was achievement of remission. Results. At 8 and 24 weeks, 7/12 and 6/12 receiving anakinra and 5/10 and 2/10 receiving DMARD achieved remission. Anakinra induced greater improvement in physical health measured by Medical Outcomes Study Short-Form 36 (SF-36; p < 0.011). During an open-label extension (OLE) of 28 weeks, 7/14 patients taking anakinra and 2/3 taking DMARD were in remission. Conclusion. Anakinra induced more beneficial responses than DMARD in patients with AOSD and was favored in the OLE phase. (ClinicalTrials.gov Protocol Registration NCT01033656).
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14429. |
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14430. |
- Nordström, Henrik, et al.
(författare)
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Microarray technology for identification and distinction of hantaviruses.
- 2004
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Ingår i: Journal of Medical Virology. - : Wiley. - 0146-6615 .- 1096-9071. ; 72:4, s. 646-655
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Tidskriftsartikel (refereegranskat)abstract
- DNA microarrays combine high-precision technology with advanced molecular biology to achieve high-throughput screening of DNA fragments. In this study, we investigated the potential of the cDNA microarray technique to identify and discriminate PCR derived amplicons from genetically highly similar viruses. The wide range of sequence variation among hantaviruses makes them suitable as a model for this purpose. The hantaviruses, carried by rodents, cause several hundred thousand cases of severe human disease every year in many parts of the world. A hantavirus-specific microarray, including DNA fragments from 12 viral isolates of six different hantaviruses, was designed. The S and M genome segments were represented by 500-nucleotide overlapping and 250-nucleotide non-overlapping fragments. A considerable ability to distinguish between different hantaviruses was demonstrated using a novel analysis method. Even different isolates of a single virus, were identified correctly despite 90% sequence similarity. The distinction ability was accompanied by a tolerance for smaller sequence differences, which makes the microarray suitable for testing samples containing unknown viruses. Viral genetic material found in samples from the lungs of bank voles caught in the wild was identified precisely, which demonstrated further the potential for this technology.
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