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- Brodd, Katarina Strand, et al.
(författare)
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Development of Smooth Pursuit Eye Movements in very preterm born infants : 3. Association to perinatal risk factors
- 2012
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Ingår i: Acta Paediatrica. - : Wiley. - 0803-5253 .- 1651-2227. ; 101:2, s. 164-171
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Tidskriftsartikel (refereegranskat)abstract
- Aim: To investigate the association between perinatal risk factors and neonatal complications and early oculo-motor development in very preterm infants. Methods: Perinatal risk factors were identified, and the potential association with early oculo-motor development was evaluated by measuring smooth pursuit eye movements (SP) at 2 and 4 months' corrected age (CA) in a population of very preterm infants born in Uppsala County 2004-2007 (n = 113). Results: Among the 15 tested factors, eight showed significant association in univariate analysis with lower levels of SP at 4 months' CA, namely administration of prenatal corticosteroids, gestational age, birthweight, bronchopulmonary dysplasia, retinopathy of prematurity, periventricular leukomalacia, intraventricular haemorrhage >grade 2, and persistent ductus arteriosus. At 2 months' CA, only retinopathy of prematurity >stage 2 was associated with lower levels of SP. When all factors significant in the univariate tests were included in multiple regressions aimed to assess each factor's independent relation to SP, periventricular leukomalacia was the only significant independent factor. When adding 2-5 of the significant factors using multiple regression analysis, the levels of SP became lower. Conclusion: Perinatal risk factors were associated with lower levels of SP. This could be interpreted as delayed or disturbed development of normal oculomotor ability.
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- Brodd, Katarina Strand, et al.
(författare)
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Development of smooth pursuit eye movements in very preterm infants : 1. General aspects
- 2011
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Ingår i: Acta Paediatrica. - : Wiley. - 0803-5253 .- 1651-2227. ; 100:7, s. 983-991
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Tidskriftsartikel (refereegranskat)abstract
- Aim: To investigate early oculo-motor development in a population-based cohort of very preterm infants.Methods: Early oculo-motor development was prospectively studied by measuring smooth pursuit eye movements at 2 and 4 months corrected age in a population of very preterm infants born in Uppsala County 2004–2007. Eighty-one preterm infants were studied, and 32 healthy term infants constituted the control group.Results: The study group consisted of infants with a mean gestational age of28 + 5 weeks. At 2 and 4 months corrected age, infants born very preterm showed lower gain (p < 0.001) and proportion of smooth pursuit eyemovements (p < 0.001) compared to the control group. The boys showed higher gain of smooth pursuit eye movements at both 2 and 4 months corrected age, compared to girls.Conclusions: Oculo-motor development measured by smooth pursuit eye movements is delayed in very preterm infants at 2 and 4 months corrected age. This might be a risk factor or early indicator of later perceptual and behavioural impairment.
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- Enbom, Malin, et al.
(författare)
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Detection of Epstein-Barr virus, but not human herpesvirus 8, DNA in cervical secretions from Swedish women by real-time polymerase chain reaction
- 2001
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Ingår i: Sexually Transmitted Diseases. - : Ovid Technologies (Wolters Kluwer Health). - 0148-5717 .- 1537-4521. ; 28:5, s. 300-306
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Epstein-Barr virus (EBV) and human herpesvirus 8 (HHV-8) are two related herpesviruses that may be sexually transmitted. GOAL: To examine the presence of HHV-8 and EBV DNA in the female genital tract. STUDY DESIGN: Real-time polymerase chain reaction systems for quantification of DNA from HHV-8, EBV, and herpes simplex virus type 2 were developed and used for examination of cervical secretions from 112 Swedish women. HHV-8, EBV, and herpes simplex virus type 2 serology was also performed on samples from all subjects. RESULTS: EBV DNA was found in 10 cervical secretion samples, sometimes in high amounts. No cervical secretion or leukocyte sample contained detectable HHV-8 DNA. Antibodies to HHV-8-latent and -lytic antigens were found in 2.7 % and 24% of serum samples, respectively. CONCLUSION: This study supports a possible sexual route of transmission for EBV but not for HHV-8. The new real-time polymerase chain reaction systems could be valuable in future studies of relations between virus load and disease
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- Fredriksson Kaul, Ylva
(författare)
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From Eye to Mind : Early Visuomotor Performance and Developmental Trajectories in Children Born Preterm
- 2022
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Children born very preterm, at less than 32 weeks of gestation, have an increased risk of developing problems with attention, cognition, perception and motor function. Despite this, the developmental trajectories leading from preterm birth to later impairments are not fully understood.This thesis focused on investigating the development of the visuomotor system in infants born very preterm, in relation to neurodevelopment at 2.5-3 years (including cognitive, language and motor functions) and 6.5 years (including cognitive functions and attention). Two early visuomotor functions were investigated: at 4 months of corrected age we looked at their visual tracking of moving objects and at 8 months of corrected age we examined how they reached for moving objects. Visual tracking performance is the ability to follow, sustain attention on and predict the future positions of a moving object. When infants reach for moving objects, these requirements are enhanced by movements of the arm and hand.This was a prospective, population-based cohort study of children born very preterm in 2004-2007, who were longitudinally assessed from the neonatal period until 6.5 years of age. The results showed that the two most important early visual tracking parameters were gaze gain, which is effectively combining eye and head movements to follow the trajectory of the object, and timing of gaze to the motion of the object. Gaze gain correlated with neurodevelopment at 2.5-3 years and with cognition and attention at 6.5 years. Early reaching was also related to outcomes at 2.5-3 years, but the pattern differed for children born before and after 28 weeks of gestation. Parameters of prediction and movement planning were the most important factors for the children of the lowest gestational age, but strategies and success had greater associations with later function in those who were less premature.The results confirmed that children born very preterm in the first decade of the 2000’s still faced increased risks of developmental delays. Early visual tracking performance, and reaching for moving objects, were shown to be important visuomotor functions in the developmental process of children born very preterm. The studies in this thesis illustrate how early basic functions were related to different neurodevelopmental areas at a later stage and offer important new insights into developmental trajectories of children at risk of developmental impairments. These findings suggest that attention and predictive elements of adjusting one´s movements to motion, may be key mechanisms and possible targets in future intervention studies.
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- Fredriksson Kaul, Ylva, et al.
(författare)
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Visual tracking at 4 months in preterm infants predicts 6.5-year cognition and attention
- 2022
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Ingår i: Pediatric Research. - : Springer Nature. - 0031-3998 .- 1530-0447. ; 92:4, s. 1082-1089
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Visual tracking of moving objects requires sustained attention and prediction of the object’s trajectory. We tested the hypothesis that measures of eye-head tracking of moving objects are associated to long-term neurodevelopment in very preterm infants.METHODS: Visual tracking performance was assessed at 4 month’s corrected age in 57 infants with gestational age <32 weeks. An object moved in front of the infant with sinusoidal or triangular (i.e. abrupt) turns of the direction. Gaze gain, smooth pursuit gain, and timing of gaze to object motion were analyzed. At 6.5 years the Wechsler Intelligence Scale for Children (WISC-IV), the Brown Attention Deficit Disorder (Brown ADD), and visual examination were performed. RESULTS: Gaze gain and smooth pursuit gain at 4 months were strongly related to all WISC-IV parameters at 6.5 years. Gaze gain for the triangular and sinusoidal motion patterns related similarly to the cognitive scores. For the sinusoidal motion pattern, timing related to most Brown ADD parameters. There were no statistically significant differences in associations dependent on motion pattern. Visual function did not influence the results. CONCLUSION: The ability to attend to and smoothly track a moving object in infancy is an early marker of cognition and attention at 6.5 years.
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- Granberg, Maria, et al.
(författare)
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Microlitter in arctic marine benthic food chains and potential effects on sediment dwelling fauna
- 2020
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Ingår i: TemaNord report. - : Nordic Council of Ministers. ; :528
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Tidskriftsartikel (refereegranskat)abstract
- Marine litter pollution affects oceans globally and has today also made its way to the pristine arctic environment adding to the microlitter from local pollution sources. Marine litter pollution is recognized as a serious threat to the marine environment at all levels, from the UN to regional (EU, OSPAR, HELCOM) and national authorities. The risk posed by microlitter to marine biota is related to their documented ubiquity and long residence time in marine ecosystems. Risks are also mediated by intrinsic toxicity of added chemicals and potential adsorbance of other pollutants. When released into the marine environment, a major part of microlitter likely accumulate in beach sand and marine sediments either immediately or after acquiring a biofilm. It is therefore expected that benthic food chains will be key to understanding fate and effects (i.e. concentrations, potential trophic transfer and biological impact) of microlitter in the marine environment. The overall aim of the project was to determine abundance of microlitter pollution in marine sediments and benthic food chains in the Arctic, and to evaluate the abundance in relation to potential local sources and background levels. The aim was also to investigate potential effects of microplastic pollution on benthic organisms through laboratory studies using an arctic amphipod as a model organism. The field investigations in Svalbard, Norway and Greenland focused on determining microlitter particle concentrations and characteristics in marine sediments and biota collected close to and far from potential local pollution sources and pathways, i.e. outlets of untreated wastewater and effluents from a dumping site in Sisimiut, West Greenland and outlets of treated (Ny-Ålesund) and untreated (Longyearbyen) wastewater in Svalbard. Overall, higher concentrations and a higher diversity of microlitter types and polymers were found in sediments and organisms (blue mussels and cod) closer to human settlements (wastewater outlets and dumping sites) and in places where lost and/or dumped fishing gear accumulate. Thus, we can confidently conclude that local pollution sources for anthropogenic microlitter do exist in the Arctic. The experimental studies investigated whether environmentally relevant and future predicted concentrations of microplastics could impact feeding rate, microplastic ingestion, respiration and locomotion activity in an arctic sediment dwelling amphipod. The experimental results confirm previous microplastics studies on marine invertebrates showing effect only at very high concentrations not yet relevant in the arctic environment. The shape of the plastic particles was found to affect the particle fate. While microplastic fragments were ingested, short microplastic fibres attached to the carapace of the amphipods and likely obstructed normal ventilation behaviour. Furthermore, biofilm cover was found to affect the behaviour and effects of the particles. Microlitter naturally become covered by biofilms in the environment and our results stress the importance of effect experiments being carried out using naturally fouled plastics for ecological relevance. This report provides both environmental- and impact data related to microlitter pollution in the arctic marine environment. Although the levels of microplastics required to cause effects in experimental organisms in this study were much higher than what was detected in the field, there may be other species that are more sensitive than the one tested in nature. The currently relatively low microlitter concentrations detected in the field should be considered as a “window of opportunity” to act to at least reduce local pollution. Consequently, introduction of sustainable waste management and wastewater treatment should be an important focus of local management initiatives.
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- Grönqvist, Helena, et al.
(författare)
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Development of smooth pursuit eye movements in very prematurely born infants : 2. The low-risk subgroup.
- 2011
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Ingår i: Acta Paediatrica. - : Wiley. - 0803-5253 .- 1651-2227. ; 100:7, s. e5-e11
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Tidskriftsartikel (refereegranskat)abstract
- Aim: To investigate the impact of premature birth on visual tracking in a group of 37 infants, born before the 32nd gestational weeks (mean 29 + 6 weeks) and diagnosed as being without major neonatal complications. This paper is a part of the LOVIS study (Strand Brodd, Ewald, Grönqvist, Holmström, Strömberg, Von Hofsten, et al. Acta Pediatrica, 2011). Methods: At 2 and 4 months corrected age, eye and head movements were measured when the infant tracked a moving object. The eye movements were analysed in terms of smooth pursuit and saccades (Vision Res, 37, 1997, 1799; Exp Brain Res, 146, 2002, 257). Accuracy of gaze, proportion of smooth pursuit, head movements and saccades were calculated. Results: Between 2 and 4 months of age, all infants improved their ability to smoothly pursue a moving object. However, at both occasions, the preterm infants had less proportion smooth pursuit than the full-term infants. The groups did not differ with respect to gaze and head movements, but the saccade frequency was higher for the very preterms in some of the conditions. Conclusion: The development of smooth pursuit in the low-risk preterm infant group was strongly delayed compared to typically developed infants. Thus, the 2 months or more extra visual experience did not have a distinguishable positive effect on visuo-motor development as expressed in smooth pursuit.
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- Hassellöv, Martin, et al.
(författare)
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Progress towards monitoring of microlitter in Scandinavian marine environments
- 2018
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Ingår i: TemaNord, 2018, 551, 2018. - Copenhagen : Nordic Council of Ministers.
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Tidskriftsartikel (refereegranskat)abstract
- Four different case studies were carried out to determine dominating microlitter types from urban environments to the regional Scandinavian seas (eastern North Sea). The sampling was both from sediment near sources (urban runoff and road dust sediment), and further out from coastal sediments. The sea surface layer and subsurface samples was taken in two different gradients, in the Oslo and Roskilde fjords, where also blue mussels were sampled. Best available technologies for sampling each compartment was used and evaluated, and while the water samples was analysed as collected, the sediment and biota samples needed some pretreatment of chemical digestion and/or heavy density liquid floatation or elutriation.In order to develop visual identification as objective as possible, a visual and physical observation scheme was proposed. The visual identification scheme should be complemented with spectroscopic identification to different degrees depending on the size fractions.Spectroscopic identification is still often a quite time-consuming process, meaning that for monitoring purposes it is not currently advisable to aim to identify all particles during monitoring studies. Until fully or partly automated spectroscopic methods are available they are still important tools for verification of representative types of particles in samples above 100 μm.The amount of particles that should be identified to provide adequate compositional information would be dependent on the aim of the study as well as the type and composition of the samples. However, in order to do monitoring and include sample composition in the results a minimum of 100 of the fewest particles should be counted in a sample to achieve 10% standard deviation in terms of counting statistical uncertainty.The field is however rapidly evolving, and automated procedures are already being published. For research purposes and more detailed monitoring and screening studies spectroscopic methods can aside from providing particle identification also give clues on additives and level of degradation.The most common types of microlitter found varied between studies but common trends could be identified between the road tunnel sediment and the urban creek sediment that these contained black particles resembling tire rubber from both visual and tactile tests, and also asphalt, charcoal, oil/tar particles and road marker particles. In the coastal water samples the surface layer was dominated by polystyrene foam particles and polyethylene fragments and films.In the subsurface water samples fibres, films and fragments of plastic was most common. In both the Gothenburg urban creek sediment and Oslo fjord surface water samples particles that could be related to artificial sports turf (polyethylene green grass and clear cut, tire granulate) was observed. The microlitter in mussels was dominated by fibres. The approach of using gradient studies, and include both near source sampling as well as recipient gradient sampling, was concluded to be very suitable to determine sources and fate.
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