| 2581. |
- Tachibana, T., et al.
(författare)
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Nanoplasma Formation by High Intensity Hard X-rays
- 2015
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Ingår i: Scientific Reports. - : Springer Science and Business Media LLC. - 2045-2322. ; 5
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Tidskriftsartikel (refereegranskat)abstract
- Using electron spectroscopy, we have investigated nanoplasma formation from noble gas clusters exposed to high-intensity hard-x-ray pulses at similar to 5 keV. Our experiment was carried out at the SPring-8 Angstrom Compact free electron LAser (SACLA) facility in Japan. Dedicated theoretical simulations were performed with the molecular dynamics tool XMDYN. We found that in this unprecedented wavelength regime nanoplasma formation is a highly indirect process. In the argon clusters investigated, nanoplasma is mainly formed through secondary electron cascading initiated by slow Auger electrons. Energy is distributed within the sample entirely through Auger processes and secondary electron cascading following photoabsorption, as in the hard x-ray regime there is no direct energy transfer from the field to the plasma. This plasma formation mechanism is specific to the hard-x-ray regime and may, thus, also be important for XFEL-based molecular imaging studies. In xenon clusters, photo-and Auger electrons contribute more significantly to the nanoplasma formation. Good agreement between experiment and simulations validates our modelling approach. This has wide-ranging implications for our ability to quantitatively predict the behavior of complex molecular systems irradiated by high-intensity hard x-rays.
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| 2582. |
- Tataranno, M. L., et al.
(författare)
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Morphine affects brain activity and volumes in preterms: An observational multi-center study
- 2020
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Ingår i: Early Human Development. - : Elsevier BV. - 0378-3782 .- 1872-6232. ; 144
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Tidskriftsartikel (refereegranskat)abstract
- Objective: We hypothesized that morphine has a depressing effect on early brain activity, assessed using quantitative aEEG/EEG parameter and depressed activity will be associated with brain volumes at term in extremely preterm infants. Study design: 174 preterm infants were enrolled in 3 European tertiary NICUs (mean GA:26 +/- 1wks) and monitored during the first 72 h after birth with continuous 2 channel aEEG. Six epochs of aEEG recordings were selected and minimum amplitude of aEEG (min aEEG), percentage of time amplitude< 5 mu V (% of time < 5 mu V), spontaneous activity transients (SATrate) and interSAT interval (ISI) were calculated. For infants receiving morphine, the cumulative morphine dosage was calculated. In a subgroup of 58 infants, good quality MRI at term equivalent age (TEA) and the cumulative morphine dose until TEA were available. The effects of morphine administration and cumulative dose on aEEG/EEG measures and on brain volumes were investigated. Results: Morphine administration had a significant effect on all quantitative aEEG/EEG measures, causing depression of early brain activity [longer ISI (beta 2.900), reduced SAT rate (beta -1.386), decreased min aEEG (beta -0.782), and increased % of time < 5 mu V (beta 14.802)] in all epochs. A significant effect of GA and postnatal age on aEEG/EEG measures was observed. Cumulative morphine dose until TEA had a significant negative effect on total brain volume (TBV) (beta -8.066) and cerebellar volume (beta -1.080). Conclusions: Administration of sedative drugs should be considered when interpreting aEEG/EEG together with the negative dose dependent morphine impact on brain development.
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| 2583. |
- Tell, David, et al.
(författare)
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Clinical course of pharyngotonsillitis with group A streptococcus treated with different penicillin V strategies, divided in groups of Centor Score 3 and 4: a prospective study in primary care
- 2022
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Ingår i: BMC Infectious Diseases. - : Springer Science and Business Media LLC. - 1471-2334. ; 22:1
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Tidskriftsartikel (refereegranskat)abstract
- Background Sore throat is a common reason for prescribing antibiotics in primary care, and 10 days of treatment is recommended for patients with pharyngotonsillitis with group A streptococcus (GAS). Our group recently showed that penicillin V (PcV) four times daily for 5 days was non-inferior in clinical outcome to PcV three times daily for 10 days. This study compares duration, intensity of symptoms, and side effects in patients with a Centor Score (CS) of 3 or 4 respectively, after treatment with PcV for 5 or 10 days and evaluates whether all patients with pharyngotonsillitis with a CS of 3 or 4 should be treated for 5 days or if severity of symptoms or CS suggest a longer treatment period. Method Data on symptoms and recovery from patient diaries from 433 patients included in a RCT comparing PcV 800 mg x 4 for 5 days or PcV 1 g x 3 for 10 days was used. Patients six years and older with CS-3 or CS-4 and positive rapid antigen detection test for GAS-infection were grouped based on CS and randomized treatment. Comparisons for categorical variables were made with Pearson's chi-squared test or Fisher's exact test. Continuous variables were compared with the Mann-Whitney U test. Results Patients with CS-3 as well as patients with CS-4 who received PcV 800 mg x 4 for 5 days self-reported that they recovered earlier compared to patients with CS-3 or CS-4 who received treatment with PcV 1 g x 3 for 10 days. In addition, the throat pain as single symptom was relieved 1 day earlier in patients with CS-4 and 5 days of treatment compared to patients with CS-4 and 10 days of treatment. No differences in side effects between the groups were found. Conclusion Intense treatment with PcV four times a day for 5 days seems clinically beneficial and strengthens the suggestion that the 4-dose regimen with 800 mg PcV for 5 days may be the future treatment strategy for GAS positive pharyngotonsillitis irrespectively of CS-3 or CS-4. Trail registration ClinicalTrials.gov ID: NCT02712307 (3 April 2016).
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| 2584. |
- Thomée, Sara, 1965, et al.
(författare)
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Cognition and mental wellbeing after electrical accidents: a survey and a clinical study among Swedish male electricians
- 2020
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Ingår i: International Archives of Occupational and Environmental Health. - : Springer Science and Business Media LLC. - 0340-0131 .- 1432-1246. ; 93:6, s. 683-96
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Tidskriftsartikel (refereegranskat)abstract
- © 2020, The Author(s). Purpose: The purpose was to examine long-term consequences of exposure to electrical current passing through the body. We investigated (1) whether electricians after having experienced an electrical accident report more cognitive problems and lower mental wellbeing and (2) have objectively verifiable reduced cognitive function; and (3) which circumstances at the time of the accident affect long-term subjective cognitive function and mental wellbeing? Methods: A survey of male electricians who had experienced electrical accidents (n = 510) and a clinical study in a subsample (n = 23) who reported residual health problems was carried out. Both groups were examined regarding subjective cognitive function (Euroquest-9) and mental wellbeing (Symptom Checklist-90 subscales). The clinical study included neuropsychological tests of memory, attention, spatial function, and premorbid intellectual capacity. A matched control group was retrieved from reference data. Results: The survey participants reported more cognitive problems and lower mental wellbeing than referents. Of the examined circumstances, having experienced mortal fear at the time of the accident and health complaints, especially mental symptoms, for > 1week after the accident were the most significant risk factors for later subjective cognitive problems and lower mental wellbeing. The only statistically significant difference in neuropsychological tests was better performance in part of the memory tests by the clinical study group compared to the control group. Conclusions: The participants reported more cognitive problems and lower mental wellbeing than referents, but no long-term objective cognitive dysfunction was detected. Emotional response at the time of the accident and health complaints in the aftermath of the accident may constitute important indications for medical and psychological follow-ups.
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| 2585. |
- Thorven, Maria, et al.
(författare)
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A homozygous nonsense mutation (428G ->A) in the human secretor (FUT2) gene provides resistance to symptomatic norovirus (GGII) infections
- 2005
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Ingår i: Journal of Virology. - 0022-538X .- 1098-5514. ; 79:24, s. 15351-5
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Tidskriftsartikel (refereegranskat)abstract
- Noroviruses (formerly Norwalk-like viruses) are a major cause of acute gastroenteritis worldwide and are associated with a significant number of nosocomial and food-borne outbreaks. In this study we show that the human secretor FUT2 gene, which codes for an alpha(1,2)-fucosyltransferase synthesizing the H-type 1 antigen in saliva and mucosa, is associated with susceptibility to norovirus infections. Allelic polymorphism characterization at nucleotide 428 for symptomatic (n = 53) and asymptomatic (n = 62) individuals associated with nosocomial and sporadic norovirus outbreaks revealed that homozygous nonsense mutation (428G-->A) in FUT2 segregated with complete resistance for the disease. Of all symptomatic individuals, 49% were homozygous (SeSe) and 51% heterozygous (Sese428) secretors, and none were secretor negative (se428se428), in contrast to 20% nonsecretors (se428se428) among Swedish blood donors (n = 104) (P < 0.0002) and 29% for asymptomatic individuals associated with nosocomial outbreaks (P < 0.00001). Furthermore, saliva from secretor-positive and symptomatic patients but not from secretor-negative and asymptomatic individuals bound the norovirus strain responsible for that particular outbreak. This is the first report showing that the FUT2 nonsecretor (se428se428) genotype is associated with resistance to nosocomial and sporadic outbreaks with norovirus.
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| 2586. |
- Tingberg, Anders, et al.
(författare)
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Evaluation of image quality of lumbar spine images: a comparison between FFE and VGA.
- 2005
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Ingår i: Radiation protection dosimetry. - : Oxford University Press (OUP). - 0144-8420 .- 1742-3406. ; 114:1-3, s. 53-61
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Tidskriftsartikel (refereegranskat)abstract
- PURPOSE: The aim of the present study is to compare two different methods for evaluation of the quality of clinical X-ray images. METHODS: Based on fifteen lumbar spine radiographs, two new sets of images were created. A hybrid image set was created by adding two distributions of artificial lesions to each original image. The image quality parameters spatial resolution and noise were manipulated and a total of 210 hybrid images were created. A set of 105 disease-free images was created by applying the same combinations of spatial resolution and noise to the original images. The hybrid images were evaluated with the free-response forced error experiment (FFE) and the normal images with visual grading analysis (VGA) by nine experienced radiologists. RESULTS: In the VGA study, images with low noise were preferred over images with higher noise levels. The alteration of the MTF had a limited influence on the VGA score. For the FFE study, the visibility of the lesions was independent of the sharpness and the noise level. No correlation was found between the two image quality measures. CONCLUSIONS: FFE is a precise method for evaluation of image quality, but the results are only valid for the type of lesion used in the study, whereas VGA is a more general method for clinical image quality assessment. The results of the FFE study indicate that there might be a potential to lower the dose levels in lumbar spine radiography without losing important diagnostic information.
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| 2587. |
- Tingberg, Anders, et al.
(författare)
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Influence of the characteristic curve on the clinical image quality of lumbar spine and chest radiographs.
- 2004
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Ingår i: The British journal of radiology. - : British Institute of Radiology. - 0007-1285 .- 1748-880X. ; 77:915, s. 204-15
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Tidskriftsartikel (refereegranskat)abstract
- The "European Guidelines on Quality Criteria for Diagnostic Radiographic Images" do not address the choice of the film characteristic (H&D) curve, which is an important parameter for the description of a radiographic screen-film system. The image contrast of clinical lumbar spine and chest radiographs was altered by digital image processing techniques, simulating images with different H&D curves, both steeper and flatter than the original. The manipulated images were printed on film for evaluation. Seven experienced radiologists evaluated the clinical image quality by analysing the fulfilment of the European Image Criteria (ICS) and by visual grading analysis (VGA) of in total 224 lumbar spine and 360 chest images. A parallel study of the effect of the H&D curve has also been made using a theoretical model. The contrast (DeltaOD) of relevant anatomical details was calculated, using a Monte Carlo simulation-model of the complete imaging system including a 3D voxel phantom of a patient. Correlations between the calculated contrast and the radiologists' assessment by VGA were sought. The results of the radiologists' assessment show that the quality in selected regions of lumbar spine and chest images can be significantly improved by the use of films with a steeper H&D curve compared with the standard latitude film. Significant (p<0.05) correlations were found between the VGA results and the calculations of the contrast of transverse processes and trabecular details in the lumbar spine vertebrae, and with the contrast of blood vessels in the retrocardiac area of the chest.
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| 2588. |
- Tivesten, Åsa, 1969, et al.
(författare)
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Dehydroepiandrosterone and its Sulfate Predict the 5-Year Risk of Coronary Heart Disease Events in Elderly Men
- 2014
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Ingår i: Journal of the American College of Cardiology. - : Elsevier BV. - 0735-1097 .- 1558-3597. ; 64:17, s. 1801-1810
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND The adrenal sex hormone dehydroepiandrosterone (DHEA), which is present in serum mainly as the sulfate DHEA-S, is the most abundant steroid hormone in human blood. Its levels decline dramatically with age. Despite the great amount of literature on vascular and metabolic actions of DHEA/-S, evidence for an association between DHEA/-S levels and cardiovascular events is contradictory. OBJECTIVES This study tested the hypothesis that serum DHEA and DHEA-S are predictors of major coronary heart disease (CHD) and/or cerebrovascular disease (CBD) events in a large cohort of elderly men. METHODS We used gas and liquid chromatography-mass spectrometry to analyze baseline levels of DHEA and DHEA-S in the prospective population-based Osteoporotic Fractures in Men study in Sweden (2,416 men, ages 69 to 81 years). Complete cardiovascular clinical outcomes were available from national Swedish registers. RESULTS During the 5-year follow-up, 302 participants experienced a CHD event, and 225 had a CBD event. Both DHEA and DHEA-S levels were inversely associated with the age-adjusted risk of a CHD event; the hazard ratios and 95% confidence intervals per SD increase were 0.82 (0.73 to 0.93) and 0.86 (0.77 to 0.97), respectively. In contrast, DHEA/-S showed no statistically significant association with the risk of CBD events. The association between DHEA and CHD risk remained significant after adjustment for traditional cardiovascular risk factors, serum total testosterone and estradiol, C-reactive protein, and renal function, and remained unchanged after exclusion of the first 2.6 years of follow-up to reduce reverse causality. CONCLUSIONS Low serum levels of DHEA and its sulfate predict an increased risk of CHD, but not CBD, events in elderly men. (C) 2014 by the American College of Cardiology Foundation.
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| 2589. |
- Tivesten, Åsa, 1969, et al.
(författare)
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Low serum testosterone and estradiol predict mortality in elderly men.
- 2009
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Ingår i: The Journal of clinical endocrinology and metabolism. - : The Endocrine Society. - 1945-7197 .- 0021-972X. ; 94:7, s. 2482-8
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Tidskriftsartikel (refereegranskat)abstract
- CONTEXT: Age-related reduction of serum testosterone may contribute to the signs and symptoms of aging, but previous studies report conflicting evidence about testosterone levels and male mortality. No large prospective cohort study has determined a possible association between serum estradiol and mortality in men. OBJECTIVE: The main objective was to examine the association between serum testosterone and estradiol and all-cause mortality in elderly men. DESIGN, SETTING, AND PARTICIPANTS: We used specific gas chromatography-mass spectrometry to analyze serum sex steroids at baseline in older men who participated in the prospective population-based MrOS Sweden cohort (n = 3014; mean age, 75 yr; range, 69-80 yr). MAIN OUTCOME MEASURE: All-cause mortality by serum testosterone and estradiol levels. RESULTS: During a mean follow-up period of 4.5 yr, 383 deaths occurred. In multivariate hazards regression models, low levels (within quartile 1 vs. quartiles 2-4) of both testosterone [hazard ratio (HR), 1.65; 95% confidence interval (CI), 1.29-2.12] and estradiol (HR, 1.54; 95% CI, 1.22-1.95) associated with mortality. A model including both hormones showed that both low testosterone (HR, 1.46; 95% CI, 1.11-1.92) and estradiol (HR, 1.33; 95% CI, 1.02-1.73) predicted mortality. Risk of death nearly doubled (HR, 1.96; 95% CI, 1.46-2.62) in subjects with low levels of both testosterone and estradiol compared with subjects within quartiles 2-4 of both hormones. CONCLUSIONS: Elderly men with low serum testosterone and estradiol have increased risk of mortality, and subjects with low values of both testosterone and estradiol have the highest risk of mortality.
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| 2590. |
- Tobieson, Lovisa, et al.
(författare)
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Extracellular fluid, cerebrospinal fluid and plasma biomarkers of axonal and neuronal injury following intracerebral hemorrhage
- 2021
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Ingår i: Scientific Reports. - : Springer Science and Business Media LLC. - 2045-2322. ; 11:1
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Tidskriftsartikel (refereegranskat)abstract
- Spontaneous intracerebral hemorrhage (ICH) is the most devastating form of stroke. To refine treatments, improved understanding of the secondary injury processes is needed. We compared energy metabolic, amyloid and neuroaxonal injury biomarkers in extracellular fluid (ECF) from the perihemorrhagic zone (PHZ) and non-injured (NCX) brain tissue, cerebrospinal fluid (CSF) and plasma. Patients (n = 11; age 61 +/- 10 years) undergoing ICH surgery received two microdialysis (MD) catheters, one in PHZ, and one in NCX. ECF was analysed at three time intervals within the first 60 h post- surgery, as were CSF and plasma samples. Amyloid-beta (A beta) 40 and 42, microtubule associated protein tau (tau), and neurofilament-light (NF-L) were analysed using Single molecule array (Simoa) technology. Median biomarker concentrations were lowest in plasma, higher in ECF and highest in CSF. Biomarker levels varied over time, with different dynamics in the three fluid compartments. In the PHZ, ECF levels of A beta 40 were lower, and tau higher when compared to the NCX. Altered levels of A beta peptides, NF-L and tau may reflect brain tissue injury following ICH surgery. However, the dynamics of biomarker levels in the different fluid compartments should be considered in the study of pathophysiology or biomarkers in ICH patients.
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