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  • 1.
    Adamus-Gorka, Magdalena
    et al.
    Stockholm University, Faculty of Science, Medical Radiation Physics (together with KI).
    Mavroidis, Panayiotis
    Stockholm University, Faculty of Science, Medical Radiation Physics (together with KI).
    Brahme, Anders
    Stockholm University, Faculty of Science, Medical Radiation Physics (together with KI).
    Lind, Bengt K
    Stockholm University, Faculty of Science, Medical Radiation Physics (together with KI).
    An “Effective functional subunit size” model for the dose response of rat spinal cord paralysis2007In: 13th International Congress of Radiation Research, San Fransisco, USA, July 8-12, 2007, 2007Conference paper (Other (popular science, discussion, etc.))
    Abstract [en]

    Background: Radiobiological models for normal tissue complication probability (NTCP) are more and more commonly used in order to estimate the clinical outcome of radiation therapy. A normal tissue complication probability model to be considered a good and reliable one should fulfill the following two requirements: (a) it should predict the sigmoid shape of the dose-response curve as well as possible and (b) it should duly handle the volume effect. In the work from 2005 (IJROBP 61(3):892-900, 2005) P. van Luijk et al. suggest that none of the existing NTCP models is able to describe the volume effects present in the rat spinal cord during irradiation with small proton beams and they indicate the need for developing such new models.

    Methods: We have used the experimental data from H. Bijl et al. (IJROBP 52(1):205-211, 2002) to try explaining the change in the fifty percent effective dose (ED50) for different field sizes. We initiated this study to evaluate whether the induction of white matter necrosis in rat spinal cord after irradiation with small proton beams could be explained independent of used NTCP model. We therefore introduced a new concept of effective FSU dose, where a convolution of the original dose distribution with a function describing the effective size of a single FSU results in the average doses in a functional subunit. Such procedure allows determining the ED50 in an FSU of a certain size, within the irradiation field. We have also looked at non uniform dose distributions to see whether using a similar method we can explain the so called “bath and shower experiments” (IJROBP 57(1): 274-281, 2003).

    Results: Using the least square method to compare the effective doses for different sizes of functional subunits with the experimental data we observe the best fit for about 8 mm length. It seems that this length could be understood as an effective size of functional subunits in rat spinal cord, explaining what is otherwise interpreted as a volume effect. For the non uniform dose distributions an effective FSU length of 5 mm gives the optimal fit with the Probit dose-response model.

    Conclusions: The concept of an effective FSU length seems to explain at least part of the effects seen when small portions of the rat spinal cord are irradiated. The most likely FSU length for the shower and bath experiments is 5 mm according to these calculations.

  • 2.
    Addo, Rebecka N.
    et al.
    Stockholm University, Faculty of Social Sciences, Department of Psychology, Perception and psychophysics. Uppsala University, Sweden.
    Wiens, Stefan
    Stockholm University, Faculty of Social Sciences, Department of Psychology, Perception and psychophysics.
    Nord, Marie
    Stockholm University, Faculty of Social Sciences, Department of Psychology, Perception and psychophysics.
    Larsson, Maria
    Stockholm University, Faculty of Social Sciences, Department of Psychology, Perception and psychophysics.
    Olfactory Functions in Adults With Autism Spectrum Disorders2017In: Perception, ISSN 0301-0066, E-ISSN 1468-4233, Vol. 46, no 3-4, p. 530-537Article in journal (Refereed)
    Abstract [en]

    Autism spectrum disorders (ASD) are often characterized by atypical sensory behavior (hyperor hyporeactivity) although evidence is scarce regarding olfactory abilities in ASD; 16 adults with high-functioning ASD (mean age: 38.2, SD: 9.7) and 14 healthy control subjects (mean age: 42.0 years, SD: 12.5) were assessed in odor threshold, free and cued odor identification, and perceived pleasantness, intensity, and edibility of everyday odors. Although results showed no differences between groups, the Bayes Factors (close to 1) suggested that the evidence for no group differences on the threshold and identification tests was inconclusive. In contrast, there was some evidence for no group differences on perceived edibility (BF01 = 2.69) and perceived intensity (BF01 = 2.80). These results do not provide conclusive evidence for or against differences between ASD and healthy controls on olfactory abilities. However, they suggest that there are no apparent group differences in subjective ratings of odors.

  • 3.
    Adlerz, Linda
    et al.
    Stockholm University, Faculty of Science, Department of Neurochemistry and Neurotoxicology.
    Beckman, Marie
    Stockholm University, Faculty of Science, Department of Neurochemistry and Neurotoxicology.
    Holback, Sofia
    Stockholm University, Faculty of Science, Department of Neurochemistry and Neurotoxicology.
    Tehranian, Roya
    Stockholm University, Faculty of Science, Department of Neurochemistry and Neurotoxicology.
    Cortés Toro, Veronica
    Stockholm University, Faculty of Science, Department of Neurochemistry and Neurotoxicology.
    Iverfeldt, Kerstin
    Stockholm University, Faculty of Science, Department of Neurochemistry and Neurotoxicology.
    Accumulation of the amyloid precursor-like protein APLP2 and reduction of APLP1 in retinoic acid-differentiated human neuroblastoma cells upon curcumin-induced neurite retraction2003In: Brain Research. Molecular Brain Research, ISSN 0169-328X, E-ISSN 1872-6941, Vol. 119, no 1, p. 62-72Article in journal (Refereed)
    Abstract [en]

    Amyloid precursor protein (APP) belongs to a conserved gene family, also including the amyloid precursor-like proteins, APLP1 and APLP2. The function of these three proteins is not yet fully understood. One of the proposed roles of APP is to promote neurite outgrowth. The aim of this study was to investigate the regulation of the expression levels of APP family members during neurite outgrowth. We observed that retinoic acid (RA)-induced neuronal differentiation of human SH-SY5Y cells resulted in increased expression of APP, APLP1 and APLP2. We also examined the effect of the NFκB, AP-1 and c-Jun N-terminal kinase inhibitor curcumin (diferuloylmethane) on the RA-induced expression levels of these proteins. We found that treatment with curcumin counteracted the RA-induced mRNA expression of all APP family members. In addition, we observed that curcumin treatment resulted in neurite retraction without any effect on cell viability. Surprisingly, curcumin had differential effects on the APLP protein levels in RA-differentiated cells. RA-induced APLP1 protein expression was blocked by curcumin, while the APLP2 protein levels were further increased. APP protein levels were not affected by curcumin treatment. We propose that the sustained levels of APP and the elevated levels of APLP2, in spite of the reduced mRNA expression, are due to altered proteolytic processing of these proteins. Furthermore, our results suggest that APLP1 does not undergo the same type of regulated processing as APP and APLP2.

  • 4.
    Adlerz, Linda
    et al.
    Stockholm University, Faculty of Science, Department of Neurochemistry and Neurotoxicology.
    Soomets, Ursel
    Stockholm University, Faculty of Science, Department of Neurochemistry and Neurotoxicology. University of Tartu, Estonia.
    Holmlund, Linda
    Stockholm University, Faculty of Science, Department of Neurochemistry and Neurotoxicology.
    Virland, Saade
    Langel, Ülo
    Stockholm University, Faculty of Science, Department of Neurochemistry and Neurotoxicology.
    Iverfeldt, Kerstin
    Stockholm University, Faculty of Science, Department of Neurochemistry and Neurotoxicology.
    Down-regulation of amyloid precursor protein by peptide nucleic acid oligomer in cultured rat primary neurons and astrocytes2003In: Neuroscience Letters, ISSN 0304-3940, E-ISSN 1872-7972, Vol. 336, no 1, p. 55-59Article in journal (Refereed)
    Abstract [en]

    The amyloid precursor protein (APP) and its proteolytic cleavage products, the amyloid P peptides, have been implicated as a cause of Alzheimer's disease. Peptide nucleic acids (PNA), the DNA mimics, have been shown to block the expression of specific proteins at both transcriptional and translational levels. Generally, the cellular uptake of PNA is low. However, recent studies have indicated that the effect of unmodified antisense PNA uptake is more pronounced in nervous tissue. In this study we have shown that biotinylated PNA directed to the initiator codon region of the APP mRNA (-4 - +11) was taken up into the cytoplasm of primary rat cerebellar granule cells and cortical astrocytes, using fluorescence and confocal microscopy studies. Uptake of PNA was faster in neurons than in astrocytes. Western blotting analysis showed that APP was strongly down-regulated in both neurons and astrocytes. Thus, unmodified PNA can be used for studies on the function of APP in neurons and astrocytes.

  • 5.
    Agahi, Neda
    et al.
    Stockholm University, Faculty of Social Sciences, Aging Research Center (ARC), (together with KI).
    Fors, Stefan
    Stockholm University, Faculty of Social Sciences, Aging Research Center (ARC), (together with KI).
    Fritzell, Johan
    Stockholm University, Faculty of Social Sciences, Aging Research Center (ARC), (together with KI).
    Shaw, Benjamin A.
    Smoking and Physical Inactivity as Predictors of Mobility Impairment During Late Life: Exploring Differential Vulnerability Across Education Level in Sweden2018In: The journals of gerontology. Series B, Psychological sciences and social sciences, ISSN 1079-5014, E-ISSN 1758-5368, Vol. 73, no 4, p. 675-683Article in journal (Refereed)
    Abstract [en]

    Objectives: To test whether older adults from high and low educational groups are differentially vulnerable to the impact of smoking and physical inactivity on the progression of mobility impairment during old age.

    Methods: A nationally representative sample of older Swedish adults (n = 1,311), aged 57-76 years at baseline (1991), were followed for up to 23 years (2014). Multilevel regression was used to estimate individual trajectories of mobility impairment over the study period and to test for differences in the progression of mobility impairment on the basis of smoking status, physical activity status, and level of education.

    Results: Compared to nonsmokers, heavy smokers had higher levels and steeper increases in mobility impairment with advancing age. However, there were only small and statistically nonsignificant differences in the impact of heavy smoking on mobility impairment in high versus low education groups. A similar pattern of results was found for physical inactivity.

    Discussion: Differential vulnerability to unhealthy behaviors may vary across populations, age, time-periods, and health outcomes. In this study of older adults in Sweden, low and high education groups did not differ significantly in their associations between heavy smoking or physical inactivity, and the progression of mobility impairment.

  • 6.
    Agahi, Neda
    et al.
    Stockholm University, Faculty of Social Sciences, Aging Research Center (ARC), (together with KI).
    Kelfve, Susanne
    Stockholm University, Faculty of Social Sciences, Department of Sociology. Stockholm University, Faculty of Social Sciences, Aging Research Center (ARC), (together with KI).
    Lennartsson, Carin
    Stockholm University, Faculty of Social Sciences, Aging Research Center (ARC), (together with KI).
    Kåreholt, Ingemar
    Stockholm University, Faculty of Social Sciences, Aging Research Center (ARC), (together with KI). Jönköping University, Sweden.
    Alcohol consumption in very old age and its association with survival: A matter of health and physical function2016In: Drug And Alcohol Dependence, ISSN 0376-8716, E-ISSN 1879-0046, Vol. 159, p. 240-245Article in journal (Refereed)
    Abstract [en]

    Background: Alcohol consumption in very old age is increasing; yet, little is known about the personal and health-related characteristics associated with different levels of alcohol consumption and the association between alcohol consumption and survival among the oldest old. Methods: Nationally representative data from the Swedish Panel Study of Living Conditions of the Oldest Old (SWEOLD, ages 76-101; n=863) collected in 2010/2011 were used. Mortality was analyzed unti12014. Alcohol consumption was measured with questions about frequency and amount. Drinks per month were calculated and categorized as abstainer, light-to-moderate drinker (0.5-30 drinks/month) and heavy drinker (>30 drinks/month). Multinomial logistic regressions and Laplace regressions were performed. Results: Compared to light-to-moderate drinkers, abstainers had lower levels of education and more functional health problems, while heavy drinkers were more often men, had higher levels of education, and no serious health or functional problems. In models adjusted only for age and sex, abstainers died earlier than drinkers. Among light-to-moderate drinkers, each additional drink/month was associated with longer survival, while among heavy drinkers, each additional drink/month was associated with shorter survival. However, after adjusting for personal and health-related factors, estimates were lower and no longer statistically significant. Conclusions: The association between alcohol consumption and survival in very old age seems to have an inverse J-shape; abstention and heavy use is associated with shorter survival compared to light-to moderate drinking. To a large extent, differences in survival are due to differences in baseline health and physical function.

  • 7. Agdal, Maren Lillehaug
    et al.
    Raadal, Magne
    Öst, Lars-Göran
    Stockholm University, Faculty of Social Sciences, Department of Psychology.
    Skaret, Erik
    Quality-of-life before and after cognitive behavioral therapy (CBT) in patients with intra-oral injection phobia2012In: Acta Odontologica Scandinavica, ISSN 0001-6357, E-ISSN 1502-3850, Vol. 70, no 6, p. 463-470Article in journal (Refereed)
    Abstract [en]

    Objective. To evaluate quality-of-life (QoL), before and after cognitive behavioral therapy (CBT) in patients diagnosed with intra-oral injection phobia according to DSM-IV and to compare with the general population. This study also aimed to evaluate if QoL was associated with self-reported injection anxiety, dental anxiety, time since last dental treatment and oral health. Materials and methods. Subjects were 55 patients (mean age 35.5 +/- 12.2, 78.2% women) who participated in a treatment study in which 89% managed an intra-oral injection at 1 year follow-up. The patients completed a set of questionnaires including Quality of Life Inventory (QOLI), Injection Phobia Scale-Anxiety, Dental Anxiety Scale and a single-item question assessing self-perceived oral health. Objective measures of oral health and treatment needs were based on clinical examination. QOLI-scores from a non-clinical sample were used for comparison. Results. Before treatment the general and health specific QoL were lower among intra-oral injection phobics than in the non-clinical sample. At 1 year follow-up the QoL in general had improved significantly and was similar to that of the non-clinical sample. Poor self-reported oral health and long-term avoidance of dental treatment were associated with lower general and health-specific QoL. Self-reported injection anxiety and dental anxiety were not associated with QoL. Conclusions. Patients with intra-oral injection phobia report lower QoL compared with a general population. Phobia treatment seems to increase QoL to normative levels. Self-perceived poor oral health is associated with reduced QoL in these patients.

  • 8. Agréus, Lars
    et al.
    Hellström, Per M.
    Talley, Nicholas J.
    Wallner, Bengt
    Forsberg, Anna
    Vieth, Michael
    Veits, Lothar
    Björkegren, Karin
    Engstrand, Lars
    Andreasson, Anna
    Stockholm University, Faculty of Social Sciences, Stress Research Institute. Karolinska Institutet, Sweden.
    Towards a healthy stomach? Helicobacter pylori prevalence has dramatically decreased over 23 years in adults in a Swedish community2016In: United European Gastroenterology journal, ISSN 2050-6406, E-ISSN 2050-6414, Vol. 4, no 5, p. 686-696Article in journal (Refereed)
    Abstract [en]

    Background In Western countries the prevalence of Helicobacter pylori (H. pylori) infection may be declining but there is a lack of recent longitudinal population studies. We evaluated the changing epidemiology over a 23-year period in Sweden. Materials and methods In 1989, the validated Abdominal Symptom Questionnaire (ASQ) was mailed to a random sample of inhabitants (ages 22-80 years) in a Swedish community, and 1097 (87%) responded. H. pylori serology was analysed in a representative subsample (n=145). Twenty-three years later, the ASQ was mailed again using similar selection criteria, and 388 out of 1036 responders had an upper endoscopy with assessment of H. pylori and corpus atrophy status. Results The prevalence of positive H. pylori serology decreased from 37.9% (1989) to 15.8% (2012), corresponding to a decrease in odds of 75% per decade (odds ratio (OR): 0.25; 95% confidence interval (CI): 0.11-0.59, p=0.001) independent of age, gender, body mass index (BMI) and level of education, with a pattern consistent with a birth cohort effect. The prevalence increased with increasing age (p=0.001). The prevalence of H. pylori on histology in 2012 was 11.4% (95% CI 8.6-15.0). The prevalence of corpus atrophy on serology and/or histology in 2012 was 3.2% (95% CI 1.8-5.5); all cases were 57 years old. Conclusion The stomach is healthier in 2012 compared with 1989. H. pylori prevalence in adults has decreased over the last two decades to a level where clinical management might be affected.

  • 9. Ahlberg, Mia
    et al.
    Ekéus, Cecilia
    Hjern, Anders
    Stockholm University, Faculty of Social Sciences, Centre for Health Equity Studies (CHESS).
    Birth by vacuum extraction delivery and school performance at 16 years of age2013In: American Journal of Obstetrics and Gynecology, ISSN 0002-9378, E-ISSN 1097-6868, Vol. 210, no 4, p. 361.e1-361.8Article in journal (Refereed)
    Abstract [en]

    Objective 

    The aim of the present study was to investigate cognitive competence, as indicated by school performance, at 16 years of age, in children delivered by vacuum extraction.

    Study design 

    This was a register study of a national cohort of 126,032 16 year olds born as singletons, with a vertex presentation, at a gestational age of 34 weeks or older, with Swedish-born parents, delivered between 1990 and 1993 without major congenital malformations. Linear regression was used to analyze mode of delivery in relation to mean scores from national tests in mathematics (40.2; scale, 10-75; SD, 14.9) and mean average grades (223.8; scale, 10-320; SD, 52.3), with adjustment for perinatal and sociodemographic confounders.

    Results

    Children delivered by vacuum extraction (-0.51; 95% confidence interval [CI], -0.76 to 0.26) as well as by nonplanned cesarean section (-0.51; 95% CI, -0.82 to -0.20) had slightly lower mean mathematics test scores than children born vaginally without instruments, after adjustment for major confounders. Mean average grades in children delivered by vacuum extraction were -1.05 (95% CI, -1.87 to -0.23) and -1.20 (95% CI,-2.24 to -0.16) in children delivered by nonplanned cesarean section compared with children born vaginally.

    Conclusion

    Children delivered by vacuum extraction had slightly lower grades at age 16 years compared with those born by noninstrumental vaginal delivery but very similar to those delivered by nonplanned cesarean. This suggests that vacuum extraction and nonplanned cesarean are equivalent alternatives for terminating deliveries with respect to cognitive outcomes.

  • 10.
    Ahrén, Jennie C.
    et al.
    Stockholm University, Faculty of Social Sciences, Centre for Health Equity Studies (CHESS).
    Chiesa, F.
    Stockholm University, Faculty of Social Sciences, Centre for Health Equity Studies (CHESS).
    Koupil, Ilona
    Stockholm University, Faculty of Social Sciences, Centre for Health Equity Studies (CHESS).
    Magnusson, C.
    Goodman, A.
    We are family - parents, siblings and eating disorders: Introducing the Stockholm Youth Cohort2012In: European psychiatry, ISSN 0924-9338, E-ISSN 1778-3585, Vol. 27, no 1, p. P-251-Article in journal (Refereed)
    Abstract [en]

    Introduction: Eating disorders (ED) are among the leading causes of disease burden, especially in women.

    Objectives: The overall aim is to explore role of parental social characteristics and family composition in the development of ED in adolescent males and females.

    Aims: We investigated associations of parental socioeconomic position, family type, number of siblings and half-siblings and history of psychiatric disease in parents with the incidence of eating disorders at age 12–23 years.

    Methods: The Stockholm Youth Cohort (N = 589,114) is a database created by record-linkage for all children and adolescents, 0–17 years, resident in Stockholm County during the period 2001–2007, their parents and siblings. Hazard rations were calculated using Cox regression. Cases of ED were identified in outpatient care.

    Results: A total of 3251 cases of ED (2971 females and 280 males) were recorded among 249,884 study subjects. There was an increased risk of ED in both male and female offspring of parents who had a history of alcohol and drug abuse or psychiatric ill-health. Higher parental education was a risk factors in females. Increasing number of full siblings had a protective effect (fully adjusted HR 0.91, 95% CI 0.87–0.96, per sibling) while increasing number of half-siblings appeared to increase risk of eating disorders in females.

    Conclusions: Risk factors for ED seem to differ between females and males. While parental psychiatric health is related to risk of ED in both sexes, family socioeconomic position and relationships within family appear to be of more importance for influencing risk of ED in females.

  • 11.
    Ahrén, Jennie C.
    et al.
    Stockholm University, Faculty of Social Sciences, Centre for Health Equity Studies (CHESS).
    Chiesa, Flaminia
    Stockholm University, Faculty of Social Sciences, Centre for Health Equity Studies (CHESS).
    Koupil, Ilona
    Stockholm University, Faculty of Social Sciences, Centre for Health Equity Studies (CHESS).
    Magnusson, Cecilia
    Karolinska Institutet.
    Dalman, Christina
    Karolinska Institutet.
    Goodman, Anna
    Stockholm University, Faculty of Social Sciences, Centre for Health Equity Studies (CHESS). London School of Hygiene and Tropical Medicine.
    We are family - parents, siblings, and eating disorders in a prospective total-population study of 250,000 Swedish males and females2013In: International Journal of Eating Disorders, ISSN 0276-3478, E-ISSN 1098-108X, Vol. 46, no 7, p. 693-700Article in journal (Refereed)
    Abstract [en]

    Objective: We examined how parental characteristics and other aspects of family background were associated with the development of eating disorders (ED) in males and females.

    Method: We used register data and record linkage to create the prospective, total-population study the Stockholm Youth Cohort. This cohort comprises all children and adolescents who were ever residents in Stockholm County between 2001 and 2007, plus their parents and siblings. Individuals born between 1984 and 1995 (N = 249, 884) were followed up for ED from age 12 to end of 2007. We used Cox regression modeling to investigate how ED incidence was associated with family socioeconomic position, parental age, and family composition.

    Results: In total, 3,251 cases of ED (2,971 females; 280 males) were recorded. Higher parental education independently predicted a higher rate of ED in females [e.g., adjusted hazard ratio (HR) 1.69 (95% CI: 1.42, 2.02) for degree-level vs. elementary-level maternal education], but not in males [HR 0.73 (95% CI: 0.42, 1.28), p < 0.001 for gender interaction]. In females, an increasing number of full-siblings was associated with lower rate of ED [e.g., fully adjusted HR 0.92 (95% CI: 0.88, 0.97) per sibling], whereas an increasing number of half-siblings was associated with a higher rate [HR 1.05 (95% CI: 1.01, 1.09) per sibling].

    Discussion: The effect of parental education on ED rate varies between males and females, whereas the effect of number of siblings varies according to whether they are full or half-siblings. A deeper understanding of these associations and their underlying mechanisms may provide etiological insights and inform the design of preventive interventions

  • 12.
    Ahrén-Moonga, Jennie
    et al.
    Stockholm University, Faculty of Social Sciences, Centre for Health Equity Studies (CHESS).
    Lekander, Mats
    Stockholm University, Faculty of Social Sciences, Stress Research Institute.
    von Blixten, Nils
    Rönnelid, Johan
    Holmgren, Sven
    af Klinteberg, Britt
    Stockholm University, Faculty of Social Sciences, Centre for Health Equity Studies (CHESS). Stockholm University, Faculty of Social Sciences, Department of Psychology.
    Levels of tumour necrosis factor-alpha and interleukin-6 in severely ill patients with eating disorders2011In: Neuropsychobiology, ISSN 0302-282X, E-ISSN 1423-0224, Vol. 63, no 1, p. 8-14Article in journal (Refereed)
    Abstract [en]

    Background: The underlying pathophysiology of eating disorders (ED) is dependent on complex interactions between psychological, biological and social factors. The purpose of the present study was to examine a possible increase in cytokines indicating inflammation, as measured by tumour necrosis factor-α (TNF-α) and interleukin-6 (IL-6) in ED patients, and to explore possible relationships between cytokines and self-reported personality traits. Methods: Female patients with severe ED (n = 26) were recruited consecutively from an inpatient clinic and were compared to age-matched healthy females (n = 12). Commercial ELISA tests developed for the measurement of serum levels of TNF-α and IL-6 were employed. Personality traits were measured using Karolinska Scales of Personality. Results: The patient group displayed increased levels of the cytokine TNF-α and a tendency towards increased IL-6 levels. Spearman's rank correlation coefficient was used to examine possible relationships between levels of cytokines and personality traits. The results showed that IL-6 levels were positively related to both somatic and psychic anxiety and to aggression scales, such as irritability and suspicion. Increased levels of TNF-α, in turn, were significantly correlated with high scores on the depression-related anxiety scale Inhibition of Aggression. However, increased levels of cytokines in the ED group did not seem to be mainly associated with symptoms of depression. Conclusion: We cannot rule out the possibility that comorbid conditions in the group contribute to the higher cytokine values. Further studies need to explore the possible influence of cytokines on the severity of ED and whether this might be mediated or moderated by specific personality traits.

  • 13. Ainsbury, E A
    et al.
    Bakhanova, E
    Barquinero, J F
    Brai, M
    Chumak, V
    Correcher, V
    Darroudi, F
    Fattibene, P
    Gruel, G
    Guclu, I
    Horn, S
    Jaworska, A
    Kulka, U
    Lindholm, C
    Lloyd, D
    Longo, A
    Marrale, M
    Monteiro Gil, O
    Oestreicher, U
    Pajic, J
    Rakic, B
    Romm, H
    Trompier, F
    Veronese, I
    Voisin, P
    Vral, A
    Whitehouse, C A
    Wieser, A
    Woda, C
    Wojcik, Andrzej
    Stockholm University, Faculty of Science, Department of Genetics, Microbiology and Toxicology.
    Rothkamm, K
    REVIEW OF RETROSPECTIVE DOSIMETRY TECHNIQUES FOR EXTERNAL IONISING RADIATION EXPOSURES.2011In: Radiation Protection Dosimetry, ISSN 0144-8420, E-ISSN 1742-3406, Vol. 147, no 4, p. 573-592Article in journal (Refereed)
    Abstract [en]

    The current focus on networking and mutual assistance in the management of radiation accidents or incidents has demonstrated the importance of a joined-up approach in physical and biological dosimetry. To this end, the European Radiation Dosimetry Working Group 10 on 'Retrospective Dosimetry' has been set up by individuals from a wide range of disciplines across Europe. Here, established and emerging dosimetry methods are reviewed, which can be used immediately and retrospectively following external ionising radiation exposure. Endpoints and assays include dicentrics, translocations, premature chromosome condensation, micronuclei, somatic mutations, gene expression, electron paramagnetic resonance, thermoluminescence, optically stimulated luminescence, neutron activation, haematology, protein biomarkers and analytical dose reconstruction. Individual characteristics of these techniques, their limitations and potential for further development are reviewed, and their usefulness in specific exposure scenarios is discussed. Whilst no single technique fulfils the criteria of an ideal dosemeter, an integrated approach using multiple techniques tailored to the exposure scenario can cover most requirements.

  • 14. Ainsbury, Elizabeth A.
    et al.
    Higueras, Manuel
    Puig, Pedro
    Einbeck, Jochen
    Samaga, Daniel
    Francesc Barquinero, Joan
    Barrios, Lleonard
    Brzozowska, Beata
    Stockholm University, Faculty of Science, Department of Molecular Biosciences, The Wenner-Gren Institute. University of Warsaw, Poland.
    Fattibene, Paola
    Gregoire, Eric
    Jaworska, Alicja
    Lloyd, David
    Oestreicher, Ursula
    Romm, Horst
    Rothkamm, Kai
    Roy, Laurence
    Sommer, Sylwester
    Terzoudi, Georgia
    Thierens, Hubert
    Trompier, Francois
    Vral, Anne
    Woda, Clemens
    Uncertainty of fast biological radiation dose assessment for emergency response scenarios2017In: International Journal of Radiation Biology, ISSN 0955-3002, E-ISSN 1362-3095, Vol. 93, no 1, p. 127-135Article in journal (Refereed)
    Abstract [en]

    Purpose: Reliable dose estimation is an important factor in appropriate dosimetric triage categorization of exposed individuals to support radiation emergency response. Materials and methods: Following work done under the EU FP7 MULTIBIODOSE and RENEB projects, formal methods for defining uncertainties on biological dose estimates are compared using simulated and real data from recent exercises. Results: The results demonstrate that a Bayesian method of uncertainty assessment is the most appropriate, even in the absence of detailed prior information. The relative accuracy and relevance of techniques for calculating uncertainty and combining assay results to produce single dose and uncertainty estimates is further discussed. Conclusions: Finally, it is demonstrated that whatever uncertainty estimation method is employed, ignoring the uncertainty on fast dose assessments can have an important impact on rapid biodosimetric categorization.

  • 15. Ainsbury, Elizabeth
    et al.
    Badie, Christophe
    Barnard, Stephen
    Manning, Grainne
    Moquet, Jayne
    Abend, Michael
    Antunes, Ana Catarina
    Barrios, Lleonard
    Bassinet, Celine
    Beinke, Christina
    Bortolin, Emanuela
    Bossin, Lily
    Bricknell, Clare
    Brzoska, Kamil
    Buraczewska, Iwona
    Huertas Castano, Carlos
    Cemusova, Zina
    Christiansson, Maria
    Mateos Cordero, Santiago
    Coster, Guillaume
    Della Monac, Sara
    Desangles, Francois
    Discher, Michael
    Dominguez, Inmaculada
    Doucha-Senf, Sven
    Eakins, Jon
    Fattibene, Paola
    Filippi, Silvia
    Frenzel, Monika
    Georgieva, Dimka
    Gregoire, Eric
    Guogyte, Kamile
    Hadjidekova, Valeria
    Hadjiiska, Ljubomira
    Hristova, Rositsa
    Karakosta, Maria
    Kis, Eniko
    Kriehuber, Ralf
    Lee, Jungil
    Lloyd, David
    Lumniczky, Katalin
    Lyng, Fiona
    Macaeva, Ellina
    Majewski, Matthaeus
    Vanda Martins, S.
    McKeever, Stephen W. S.
    Meade, Aidan
    Medipally, Dinesh
    Meschini, Roberta
    M'kacher, Radhia
    Gil, Octavia Monteiro
    Montero, Alegria
    Moreno, Mercedes
    Noditi, Mihaela
    Oestreicher, Ursula
    Oskamp, Dominik
    Palitti, Fabrizio
    Palma, Valentina
    Pantelias, Gabriel
    Pateux, Jerome
    Patrono, Clarice
    Pepe, Gaetano
    Port, Matthias
    Jesus Prieto, Maria
    Quattrini, Maria Cristina
    Quintens, Roel
    Ricoul, Michelle
    Roy, Laurence
    Sabatier, Laure
    Sebastia, Natividad
    Sholom, Sergey
    Sommer, Sylwester
    Staynova, Albena
    Strunz, Sonja
    Terzoudi, Georgia
    Testa, Antonella
    Trompier, Francois
    Valente, Marco
    Van Hoey, Olivier
    Veronese, Ivan
    Wojcik, Andrzej
    Stockholm University, Faculty of Science, Department of Molecular Biosciences, The Wenner-Gren Institute.
    Woda, Clemens
    Integration of new biological and physical retrospective dosimetry methods into EU emergency response plans - joint RENEB and EURADOS inter-laboratory comparisons2017In: International Journal of Radiation Biology, ISSN 0955-3002, E-ISSN 1362-3095, Vol. 93, no 1, p. 99-109Article in journal (Refereed)
    Abstract [en]

    Purpose: RENEB, 'Realising the European Network of Biodosimetry and Physical Retrospective Dosimetry,' is a network for research and emergency response mutual assistance in biodosimetry within the EU. Within this extremely active network, a number of new dosimetry methods have recently been proposed or developed. There is a requirement to test and/or validate these candidate techniques and inter-comparison exercises are a well-established method for such validation. Materials and methods: The authors present details of inter-comparisons of four such new methods: dicentric chromosome analysis including telomere and centromere staining; the gene expression assay carried out in whole blood; Raman spectroscopy on blood lymphocytes, and detection of radiation induced thermoluminescent signals in glass screens taken from mobile phones. Results: In general the results show good agreement between the laboratories and methods within the expected levels of uncertainty, and thus demonstrate that there is a lot of potential for each of the candidate techniques. Conclusions: Further work is required before the new methods can be included within the suite of reliable dosimetry methods for use by RENEB partners and others in routine and emergency response scenarios.

  • 16. Alakurtti, Kati
    et al.
    Johansson, Jarkko J.
    Joutsa, Juho
    Laine, Matti
    Bäckman, Lars
    Stockholm University, Faculty of Social Sciences, Aging Research Center (ARC), (together with KI).
    Nyberg, Lars
    Rinne, Juha O.
    Long-term test-retest reliability of striatal and extrastriatal dopamine D-2/3 receptor binding: study with [C-11]raclopride and high-resolution PET2015In: Journal of Cerebral Blood Flow and Metabolism, ISSN 0271-678X, E-ISSN 1559-7016, Vol. 35, no 7, p. 1199-1205Article in journal (Refereed)
    Abstract [en]

    We measured the long-term test-retest reliability of [C-11]raclopride binding in striatal subregions, the thalamus and the cortex using the bolus-plus-infusion method and a high-resolution positron emission scanner. Seven healthy male volunteers underwent two positron emission tomography (PET) [C-11]raclopride assessments, with a 5-week retest interval. D-2/3 receptor availability was quantified as binding potential using the simplified reference tissue model. Absolute variability (VAR) and intraclass correlation coefficient (ICC) values indicated very good reproducibility for the striatum and were 4.5%/0.82, 3.9%/0.83, and 3.9%/0.82, for the caudate nucleus, putamen, and ventral striatum, respectively. Thalamic reliability was also very good, with VAR of 3.7% and ICC of 0.92. Test-retest data for cortical areas showed good to moderate reproducibility (6.1% to 13.1%). Our results are in line with previous test-retest studies of [C-11]raclopride binding in the striatum. A novel finding is the relatively low variability of [C-11]raclopride binding, providing suggestive evidence that extrastriatal D-2/3 binding can be studied in vivo with [C-11]raclopride PET to be verified in future studies.

  • 17.
    Alevronta, Eleftheria
    et al.
    Stockholm University, Faculty of Science, Medical Radiation Physics (together with KI).
    Ahlberg, Alexander
    Mavroidis, Panayiotis
    Stockholm University, Faculty of Science, Medical Radiation Physics (together with KI).
    al-Abany, Massoud
    Friesland, Signe
    Tilikidis, Aris
    Laurell, Goran
    Lind, Bengt K.
    Stockholm University, Faculty of Science, Medical Radiation Physics (together with KI).
    Dose-response relations for stricture in the proximal oesophagus from head and neck radiotherapy2010In: Radiotherapy and Oncology, ISSN 0167-8140, E-ISSN 1879-0887, Vol. 97, no 1, p. 54-59Article in journal (Refereed)
    Abstract [en]

    Background and purpose: Determination of the dose-response relations for oesophageal stricture after radiotherapy of the head and neck. Material and methods: In this study 33 patients who developed oesophageal stricture and 39 patients as controls are included. The patients received radiation therapy for head and neck cancer at Karolinska University Hospital, Stockholm, Sweden. For each patient the 3D dose distribution delivered to the upper 5 cm of the oesophagus was analysed. The analysis was conducted for two periods, 1992-2000 and 2001-2005, due to the different irradiation techniques used. The fitting has been done using the relative seriality model. Results: For the treatment period 1992-2005, the mean doses were 49.8 and 33.4 Gy, respectively, for the cases and the controls. For the period 1992-2000, the mean doses for the cases and the controls were 49.9 and 45.9 Gy and for the period 2001-2005 were 49.8 and 21.4 Gy. For the period 2001-2005 the best estimates of the dose-response parameters are D-50 = 61.5 Gy (52.9-84.9 Gy), gamma = 1.4 (0.8-2.6) and s = 0.1 (0.01-0.3). Conclusions: Radiation-induced strictures were found to have a dose response relation and volume dependence (low relative seriality) for the treatment period 2001-2005. However, no dose response relation was found for the complete material.

  • 18.
    Allodi Westling, Mara
    Stockholm University, Faculty of Social Sciences, Department of Special Education.
    The experiences of mental health and well-being of Swedish children and youth with a focus on educational situations: Some results and reflections from a review of qualitative studies2010In: Trender i barns och ungdomars psykiska hälsa: Program & abstracts 12-14 april 2010, Stockholm: Kungliga vetenskapsakademien , 2010, p. 17-18Conference paper (Other academic)
    Abstract [en]

    The practice of including in reviews people’s experiences and perceptions, which are collected with non-experimental and qualitative studies, has been developed recently in the field of mental health studies. These approaches and methodologies have inspired the review of research on Swedish children and adolescents experiences of mental health and well being, with a focus on their educational situation, that was conducted as a part of a systematic review of research on School Learning and Mental health, performed by appointment of the Royal Academy of Sciences. The aim of the review was to gather testimonies that can give indications of the experiences of mental health and well being in this specific context. The results from the studies that were relevant for the aims of the review are structured in four themes: general views, protective factors, risk factors, individual factors. They are presented in a narrative synthesis, giving a particular weight to the direct and indirect report of children’s and adolescents’ own views. The adolescents defined mental health as emotional experiences, seen both as internal feelings and as relational feelings. Family, friends and educational environments as social and physical environments were perceived as determinants of mental health. A great number of feelings were related to school, both related to satisfaction and pain, in particular when the school attendance is presented as an obligation. Harassment and rejection at school, performance stress, worries about grades and future prospects could be threats against self-worth and self-esteem, while teachers that do not care could generate negative experiences. Various kind of stress could be described and various strategies to resist stressful situations: for instance emotional support, safety and involvement. The educational environments can be an arena for social, cognitive and emotional experiences, relationships and accomplishments that are enriching the individuals and increase their well being. General structural characteristics of the educational environments may also affect well being in different directions: performance, evaluation and feedback, freedom of choice and responsibility for the future may be perceived as a burden. The following reflections can be made: the experiences of children and adolescents change when they grow older, go through developmental processes and encounter different educational situations; the studies reporting views of younger children on the matters of this review were less well represented; the negative experiences may be expressed in rather cautious and non dramatic terms by younger children; there are unique contribution of the review of qualitative studies, but also several interesting correspondences with the results of the review of quantitative studies.

  • 19.
    Amoudruz, Petra
    et al.
    Stockholm University, Faculty of Science, The Wenner-Gren Institute .
    Holmlund, Ulrika
    Stockholm University, Faculty of Science, The Wenner-Gren Institute .
    Schollin, Jens
    Sverremark-Ekström, Eva
    Stockholm University, Faculty of Science, The Wenner-Gren Institute .
    Montgomery, Scott M
    Stockholm University, Faculty of Social Sciences, Department of Psychology.
    Maternal country of birth and previous pregnancies are associated with breast milk characteristics2009In: Pediatric Allergy and Immunology, ISSN 0905-6157, E-ISSN 1399-3038, Vol. 20, no 1, p. 19-29Article in journal (Refereed)
    Abstract [en]

    Populations in high infectious exposure countries are at low risk of some immune-mediated diseases such as Crohn’s disease and allergy. This low risk is maintained upon immigration to an industrialized country, but the offspring of such immigrants have a higher immune-mediated disease risk than the indigenous population. We hypothesize that early life exposures in a developing country shape the maternal immune system, which could have implications for the offspring born in a developed country with a low infectious load. The aim of this study was to investigate if exposures in childhood (indicated by country of origin) and subsequent exposures influence immunologic characteristics relevant to stimulation of offspring. Breast milk components among 64 mothers resident in Sweden, 32 of whom immigrated from a developing country, were examined using the ELISA and Cytometric Bead Array methods. Immigrants from a developing country had statistically significantly higher levels of breast milk interleukin-6 (IL-6), IL-8 and transforming growth factor-β1. A larger number of previous pregnancies were associated with down-regulation of several substances, statistically significant for soluble CD14 and IL-8. The results suggest that maternal country of birth may influence adult immune characteristics, potentially relevant to disease risk in offspring. Such a mechanism may explain the higher immune-mediated disease risk among children of migrants from a developing to developed country. Older siblings may influence disease risk through the action of previous pregnancies on maternal immune characteristics.

  • 20. Anchang-Kimbi, Judith K.
    et al.
    Achidi, Eric A.
    Apinjoh, Tobias O.
    Mugri, Regina N.
    Chi, Hanesh Fru
    Tata, Rolland B.
    Nkegoum, Blaise
    Mendimi, Joseph-Marie N.
    Sverremark-Ekström, Eva
    Stockholm University, Faculty of Science, Department of Molecular Biosciences, The Wenner-Gren Institute.
    Troye Blomberg, Marita
    Stockholm University, Faculty of Science, Department of Molecular Biosciences, The Wenner-Gren Institute.
    Antenatal care visit attendance, intermittent preventive treatment during pregnancy (IPTp) and malaria parasitaemia at delivery2014In: Malaria Journal, ISSN 1475-2875, E-ISSN 1475-2875, Vol. 13, p. 162-Article in journal (Refereed)
    Abstract [en]

    Background: The determinants and barriers for delivery and uptake of IPTp vary with different regions in sub-Saharan Africa. This study evaluated the determinants of ANC clinic attendance and IPTp-SP uptake among parturient women from Mount Cameroon Area and hypothesized that time of first ANC clinic attendance could influence uptake of IPTp-SP/dosage and consequently malaria parasite infection status at delivery. Methods: Two cross sectional surveys were carried out at the Government Medical Centre in the Mutengene Health Area, Mt Cameroon Area from March to October 2007 and June 2008 to April 2009. Consented parturient women were consecutively enrolled in both surveys. In 2007, socio-demographic data, ANC clinic attendance, gestational age, fever history and reported use/dosage of IPTp-SP were documented using a structured questionnaire. In the second survey only IPT-SP usage/dosage was recorded. Malaria parasitaemia at delivery was determined by blood smear microscopy and placental histology. Results and discussion: In 2007, among the 287 women interviewed, 2.2%, 59.7%, and 38.1% enrolled in the first, second and third trimester respectively. About 90% of women received at least one dose SP but only 53% received the two doses in 2007 and by 2009 IPTp-two doses coverage increased to 64%. Early clinic attendance was associated (P = 0.016) with fever history while being unmarried (OR = 2.2; 95% CI: 1.3-3.8) was significantly associated with fewer clinic visits (<4visits). Women who received one SP dose (OR = 3.7; 95% CI: 2.0-6.8) were more likely not to have attended >= 4visits. A higher proportion (P < 0.001) of women with first visit during the third trimester received only one dose, meanwhile, those who had an early first ANC attendance were more likely (OR = 0.4; 95% CI = 0.2 - 0.7) to receive two or more doses. Microscopic parasitaemia at delivery was frequent (P = 0.007) among women who enrolled in the third trimester and had received only one SP dose than in those with two doses. Conclusion: In the study area, late first ANC clinic enrolment and fewer clinic visits may prevent the uptake of two SP doses and education on early and regular ANC clinic visits can increase IPTp coverage.

  • 21. Andel, Ross
    et al.
    Silverstein, Merril
    Kåreholt, Ingemar
    Stockholm University, Faculty of Social Sciences, Aging Research Center (ARC), (together with KI). Jönköping University, Sweden.
    The Role of Midlife Occupational Complexity and Leisure Activity in Late-Life Cognition2015In: The journals of gerontology. Series B, Psychological sciences and social sciences, ISSN 1079-5014, E-ISSN 1758-5368, Vol. 70, no 2, p. 314-321Article in journal (Refereed)
    Abstract [en]

    OBJECTIVE: To examine whether occupational complexity of working with data or people, and cognitive or social leisure activity at midlife predicted cognition in advanced old age.

    METHODS: We used 810 eligible participants from Longitudinal Study of Living Conditions of the Oldest Old, a Swedish nationally representative study of individuals aged 77+ with cognitive assessments (an abridged version of the Mini-Mental State Exam) administered in 1992 and 2002 and linked to information about their midlife occupation and leisure activities collected in 1968 and 1981. A bootstrapping technique was applied to examine the direct and interactive associations of occupational complexity and leisure activity with late-life cognition.

    RESULTS: Controlling for demographic and health-related factors from childhood, midlife, and late life, we found that greater work complexity, both with people and with data, and greater participation in cognitive or social leisure activities independently related to better late-life cognitive scores. The complexity-cognition link was moderated by leisure activity such that the cognitive benefit related to the complexity of work-especially complexity of working with people-was rendered insignificant when participation in leisure activities-especially social activities-was above average.

    DISCUSSION: Results are discussed in terms of using work complexity to compensate for lack of leisure activity as well as in terms of promoting leisure engagement to compensate for long-term cognitive disadvantage imposed by working in less challenging occupations.

  • 22.
    Anderbro, Therese
    et al.
    Stockholm University, Faculty of Social Sciences, Department of Psychology. Karolinska Institutet, Sweden.
    Gonder-Frederick, Linda
    Bolinder, Jan
    Lins, Per-Eric
    Wredling, Regina
    Moberg, Erik
    Lisspers, Jan
    Johansson, Unn-Britt
    Fear of hypoglycemia: relationship to hypoglycemic risk and psychological factors2015In: Acta Diabetologica, ISSN 0940-5429, E-ISSN 1432-5233, Vol. 52, no 3, p. 581-589Article in journal (Refereed)
    Abstract [en]

    The major aims of this study were to examine (1) the association between fear of hypoglycemia (FOH) in adults with type 1 diabetes with demographic, psychological (anxiety and depression), and disease-specific clinical factors (hypoglycemia history and unawareness, A(1c)), including severe hypoglycemia (SH), and (2) differences in patient subgroups categorized by level of FOH and risk of SH. Questionnaires were mailed to 764 patients with type 1 diabetes including the Swedish translation of the Hypoglycemia Fear Survey (HFS) and other psychological measures including the Perceived Stress Scale, Hospital Anxiety and Depression Scale, Anxiety Sensitivity Index, Social Phobia Scale, and Fear of Complications Scale. A questionnaire to assess hypoglycemia history was also included and A(1c) measures were obtained from medical records. Statistical analyses included univariate approaches, multiple stepwise linear regressions, Chi-square t tests, and ANOVAs. Regressions showed that several clinical factors (SH history, frequency of nocturnal hypoglycemia, self-monitoring) were significantly associated with FOH but R (2) increased from 16.25 to 39.2 % when anxiety measures were added to the model. When patients were categorized by level of FOH (low, high) and SH risk (low, high), subgroups showed significant differences in non-diabetes-related anxiety, hypoglycemia history, self-monitoring, and glycemic control. There is a strong link between FOH and non-diabetes-related anxiety, as well as hypoglycemia history. Comparison of patient subgroups categorized according to level of FOH and SH risk demonstrated the complexity of FOH and identified important differences in psychological and clinical variables, which have implications for clinical interventions.

  • 23. Andersson, Gerhard
    et al.
    Bergström, Jan
    Stockholm University, Faculty of Social Sciences, Department of Psychology.
    Carlbring, Per
    Stockholm University, Faculty of Social Sciences, Department of Psychology.
    Lindefors, Nils
    The use of the Internet in the treatment of anxiety disorders2005In: Current Opinion in Psychiatry, ISSN 0951-7367, E-ISSN 1473-6578, Vol. 18, no 1, p. 73-73Article in journal (Refereed)
  • 24. Andersson, Gerhard
    et al.
    Bergström, Jan
    Stockholm University, Faculty of Social Sciences, Department of Psychology.
    Holländare, Fredrik
    Carlbring, Per
    Kaldo, Viktor
    Ekselius, Lisa
    Internet-based self-help for depression: randomised controlled trial2005In: British Journal of Psychiatry, ISSN 0007-1250, E-ISSN 1472-1465, Vol. 187, no 5, p. 456-461Article in journal (Refereed)
  • 25. Andersson, Gerhard
    et al.
    Paxling, Bjorn
    Roch-Norlund, Pie
    Stockholm University, Faculty of Social Sciences, Department of Psychology.
    Östman, Gunnar
    Stockholm University, Faculty of Social Sciences, Department of Psychology.
    Norgren, Anna
    Stockholm University, Faculty of Social Sciences, Department of Psychology.
    Almlöv, Jonas
    Georen, Lisa
    Breitholtz, Elisabeth
    Stockholm University, Faculty of Social Sciences, Department of Psychology.
    Dahlin, Mats
    Cuijpers, Pim
    Carlbring, Per
    Silverberg, Farrell
    Internet-Based Psychodynamic versus Cognitive Behavioral Guided Self-Help for Generalized Anxiety Disorder: A Randomized Controlled Trial2012In: Psychotherapy and Psychosomatics, ISSN 0033-3190, E-ISSN 1423-0348, Vol. 81, no 6, p. 344-355Article in journal (Refereed)
    Abstract [en]

    Background: Guided Internet-based cognitive behavior therapy (ICBT) has been tested in many trials and found to be effective in the treatment of anxiety and mood disorders. Generalized anxiety disorder (GAD) has also been treated with ICBT, but there are no controlled trials on guided Internet-based psychodynamic treatment (IPDT). Since there is preliminary support for psychodynamic treatment for GAD, we decided to test if a psychodynamically informed self-help treatment could be delivered via the Internet. The aim of the study was to investigate the efficacy of IPDT for GAD and to compare against ICBT and a waiting list control group. Method: A randomized controlled superiority trial with individuals diagnosed with GAD comparing guided ICBT (n = 27) and IPDT (n = 27) against a no treatment waiting list control group (n = 27). The primary outcome measure was the Penn State Worry Questionnaire. Results: While there were no significant between-group differences immediately after treatment on the main outcome measure, both IPDT and ICBT resulted in improvements with moderate to large within-group effect sizes at 3 and 18 months follow-up on the primary measure in the completer analyses. The differences against the control group, although smaller, were still significant for both PDT and CBT when conforming to the criteria of clinically significant improvement. The active treatments did not differ significantly. There was a significant group by time interaction regarding GAD symptoms, but not immediately after treatment. Conclusions: IPDT and ICBT both led to modest symptom reduction in GAD, and more research is needed.

  • 26. Andisheh, B.
    et al.
    Edgren, M.
    Belkic, Dzevad
    Stockholm University, Faculty of Science, Department of Physics.
    Mavroidis, P.
    Brahme, A.
    Lind, B. K.
    A Comparative Analysis of Radiobiological Models for Cell Surviving Fractions at High Doses2013In: Technology in Cancer Research & Treatment (Trykt), ISSN 1533-0346, E-ISSN 1533-0338, Vol. 12, no 2, p. 183-192Article in journal (Refereed)
    Abstract [en]

    For many years the linear-quadratic (LQ) model has been widely used to describe the effects of total dose and dose per fraction at low-to-intermediate doses in conventional fractionated radiotherapy. Recent advances in stereotactic radiosurgery (SRS) and stereotactic radiotherapy (SRT) have increased the interest in finding a reliable cell survival model, which will be accurate at high doses, as well. Different models have been proposed for improving descriptions of high dose survival responses, such as the Universal Survival Curve (USC), the Kavanagh-Newman (KN) and several generalizations of the LQ model, e.g. the Linear-Quadratic-Linear (LQL) model and the Pade Linear Quadratic (PLQ) model. The purpose of the present study is to compare a number of models in order to find the best option(s) which could successfully be used as a fractionation correction method in SRT. In this work, six independent experimental data sets were used: CHOAA8 (Chinese hamster fibroblast), H460 (non-small cell lung cancer, NSLC), NCI-H841 (small cell lung cancer, SCLC), CP3 and DU145 (human prostate carcinoma cell lines) and U1690 (SCLC). By detailed comparisons with these measurements, the performance of nine different radiobiological models was examined for the entire dose range, including high doses beyond the shoulder of the survival curves. Using the computed and measured cell surviving fractions, comparison of the goodness-of-fit for all the models was performed by means of the reduced e-test with a 95% confidence interval. The obtained results indicate that models with dose-independent final slopes and extrapolation numbers generally represent better choices for SRT. This is especially important at high doses where the final slope and extrapolation numbers are presently found to play a major role. The PLQ, USC and LQL models have the least number of shortcomings at all doses. The extrapolation numbers and final slopes of these models do not depend on dose. Their asymptotes for the cell surviving fractions are exponentials at low as well as high doses, and this is in agreement with the behaviour of the corresponding experimental data. This is an important improvement over the LQ model which predicts a Gaussian at high doses. Overall and for the highlighted reasons, it was concluded that the PLQ, USC and LQL models are theoretically well-founded. They could prove useful compared to the other proposed radiobiological models in clinical applications for obtaining uniformly accurate cell surviving fractions encountered in stereotactic high-dose radiotherapy as well as at medium and low doses.

  • 27.
    Andisheh, Bahram
    Stockholm University, Faculty of Science, Department of Physics.
    A comparative analysis of radio-biological models for cell-surviving fractions at high dosesManuscript (preprint) (Other academic)
    Abstract [en]

    For many years the linear-quadratic (LQ) model has been widely used to describe the effects of total dose and dose per fraction at low-to-intermediate doses in conventional fractionated radiotherapy. Recent advances in stereotactic radiosurgery (SRS) and stereotactic radiotherapy (SRT) have increased the interest in finding a reliable cell survival model, which will be accurate at high doses, as well. Different models have been proposed improving descriptions of high dose survival responses, such as the Universal Survival Curve (USC), the     Kavanagh-Newman (KN) and several generalizations of the LQ model, e.g. the Linear-Quadratic-Linear (LQL) model, the Padé Linear Quadratic (PLQ) model, etc. The purpose of the present study is to compare a number of models in order to find the best option(s) which could successfully be used as fractionation correction method in SRT.

    In this work, six independent experimental data sets were used: CHOAA8 (Chinese hamster fibroblast), H460 (non-small cell lung cancer, NSLC), NCI-H841 (small cell lung cancer, SCLC), CP3 and DU145 (human     prostate carcinoma cell lines) and U1690 (SCLC). By detailed comparisons with these measurements, the validity of nine different radiobiological models was examined for the entire dose range, including high doses   beyond the shoulder of the survival curves.

    Using the computed and measured cell surviving fractions, comparison of the goodness-of-fit for all the models was performed by means of the reduced χ2 test for a 95% confidence interval. The obtained results indicate that models with dose-independent final slopes and extrapolation numbers generally represent better choices for SRT. This is especially important at high doses where the final slope and extrapolation numbers are     presently found to play a major role.

    The PLQ, USC and LQL models have the least number of shortcomings at all doses. The extrapolation      numbers and final slopes of these models do not depend on dose. Their asymptotes for the cell surviving      fractions are exponentials at low as well as high doses, and this is in agreement with the behaviour of the    corresponding experimental data. This is an important improvement over the LQ model which predicts a Gaussian at high doses. Overall and for the highlighted reasons, it was concluded that the PLQ, USC and LQL models are theoretically well-founded and, as such, could prove useful and practical choices compare to other proposed radiobiological models in clinical applications for obtaining uniformly accurate cell surviving fractions encountered in stereotactic high-dose radiotherapy as well as at medium and low doses.

  • 28.
    Andisheh, Bahram
    et al.
    Stockholm University, Faculty of Science, Department of Physics.
    Belkic, D.
    Mavroidis, Panayiotis
    Stockholm University, Faculty of Science, Department of Physics.
    Alahverdi, M.
    Lind, B. K.
    Improving the therapeutic ratio in stereotactic radiosurgery: optimizing treatment protocols based on kinetics of repair of sublethal radiation damage2013In: Technology in Cancer Research & Treatment (Trykt), ISSN 1533-0346, E-ISSN 1533-0338, Vol. 12, no 4, p. 349-361Article in journal (Refereed)
    Abstract [en]

    Sublethal damage after radiation exposure may become lethal or be repaired according to repair kinetics. This is a well-established concept in conventional radiotherapy. It also plays an important role in single-dose stereotactic radiotherapy treatments, often called stereotactic radiosurgery, when duration of treatment is extended due to source decay or treatment planning protocol. The purpose of this study is to look into the radiobiological characteristics of normal brain tissue and treatment protocols and find a way to optimize the time course of these protocols. The general problem is nonlinear and can be solved numerically. For numerical optimization of the time course of radiation protocol, a biexponential repair model with slow and fast components was considered. With the clinically imposed constraints of a fixed total dose and total treatment time, three parameters for each fraction (dose-rate, fraction duration, time of each fraction) were simultaneously optimized. A biological optimization can be performed by maximizing the therapeutic difference between tumor control probability and normal tissue complication probability. Specifically, for gamma knife radiosurgery, this approach can be implemented for normal brain tissue or tumor voxels separately in a treatment plan. Differences in repair kinetics of normal tissue and tumors can be used to find clinically optimized protocols. Thus, in addition to considering the physical dose in tumor and normal tissue, we also account for repair of sublethal damage in both these tissues.

  • 29. Andreassen, Björn
    et al.
    Holmberg, Rickard
    Brahme, Anders
    Janek Strååt, Sara
    Stockholm University, Faculty of Science, Medical Radiation Physics (together with KI). Stockholm University, Faculty of Science, Department of Physics.
    PET/CT measurements and GEANT4 simulations of the inducedpositron activity from high energy scanned photon beamsManuscript (preprint) (Other academic)
  • 30.
    Andreassen, Björn
    et al.
    Stockholm University, Faculty of Science, Department of Physics.
    Strååt, Sara Janek
    Stockholm University, Faculty of Science, Department of Physics.
    Holmberg, Rickard
    Stockholm University, Faculty of Science, Department of Physics.
    Näfstadius, Peder
    Brahme, Anders
    Stockholm University, Faculty of Science, Department of Physics.
    Fast IMRT with narrow high energy scanned photon beams2011In: Medical physics (Lancaster), ISSN 0094-2405, Vol. 38, no 8, p. 4774-4784Article in journal (Refereed)
    Abstract [en]

    Purpose: Since the first publications on intensity modulated radiation therapy (IMRT) in the early 1980s almost all efforts have been focused on fairly time consuming dynamic or segmental multileaf collimation. With narrow fast scanned photon beams, the flexibility and accuracy in beam shaping increases, not least in combination with fast penumbra trimming multileaf collimators. Previously, experiments have been performed with full range targets, generating a broad bremsstrahlung beam, in combination with multileaf collimators or material compensators. In the present publication, the first measurements with fast narrow high energy (50 MV) scanned photon beams are presented indicating an interesting performance increase even though some of the hardware used were suboptimal. Methods: Inverse therapy planning was used to calculate optimal scanning patterns to generate dose distributions with interesting properties for fast IMRT. To fully utilize the dose distributional advantages with scanned beams, it is necessary to use narrow high energy beams from a thin bremsstrahlung target and a powerful purging magnet capable of deflecting the transmitted electron beam away from the generated photons onto a dedicated electron collector. During the present measurements the scanning system, purging magnet, and electron collimator in the treatment head of the MM50 racetrack accelerator was used with 3-6 mm thick bremsstrahlung targets of beryllium. The dose distributions were measured with diodes in water and with EDR2 film in PMMA. Monte Carlo simulations with GEANT4 were used to study the influence of the electrons transmitted through the target on the photon pencil beam kernel. Results: The full width at half-maximum (FWHM) of the scanned photon beam was 34 mm measured at isocenter, below 9.5 cm of water, 1 m from the 3 mm Be bremsstrahlung target. To generate a homogeneous dose distribution in a 10 x 10 cm(2) field, the authors used a spot matrix of 100 equal intensity beam spots resulting in a uniformity of collimated 80%-20% penumbra of 9 mm at a primary electron energy of 50 MeV. For the more complex cardioid shaped dose distribution, they used 270 spots, which at a pulse repetition frequency of 200 Hz is completed every 1.36 s. Conclusions: The present measurements indicate that the use of narrow scanned photon beams is a flexible and fast method to deliver advanced intensity modulated beams. Fast scanned photon IMRT should, therefore, be a very interesting modality in the delivery of biologically optimized radiation therapy with the possibility for in vivo treatment verification with PET-CT imaging.

  • 31.
    Andreasson, Anna
    et al.
    Stockholm University, Faculty of Social Sciences, Stress Research Institute. Karolinska Institutet, Sweden; Macquarie University, Australia.
    Carlsson, Axel C.
    Önnerhag, Kristina
    Hagström, Hannes
    Waist/Hip Ratio Better Predicts Development of Severe Liver Disease Within 20 Years Than Body Mass Index: A Population-based Cohort Study2017In: Clinical Gastroenterology and Hepatology, ISSN 1542-3565, E-ISSN 1542-7714, Vol. 15, no 8, p. 1294-+Article in journal (Refereed)
    Abstract [en]

    BACKGROUND & AIMS: Obesity, commonly assessed based on body mass index (BMI), is associated with an increased risk for severe liver disease. It is not known if other measures of body composition are better determinants of risk for severe liver disease, and/or if these differ between women and men. We investigated the body composition measures that best predict the development of severe liver disease. METHODS: We collected data from the Malmo Diet and Cancer study in Sweden, comprising 16,784 women and 10,833 (mean age, 58.1 years at baseline), and followed patients for a median 19.8 years. We analyzed data on measures of body composition including BMI, waist/hip ratio, and others. We determined whether subjects were diagnosed with severe liver disease, or died from severe liver disease, until the end of 2014 using Swedish national registers. Associations between body composition measures and severe liver disease were assessed using Cox regression models, stratified by sex and adjusted for age, alcohol consumption, smoking, education, and physical activity. RESULTS: All studied measures of body composition were significantly associated with severe liver disease. Waist/hip ratio was the best predictor of severe liver disease in women (hazard ratio [HR] per standard deviation increment, 1.30; 95% confidence interval [CI], 1.16-1.46) and men (HR, 1.46; 95% CI, 1.31-1.63). BMI had the lowest HR in women (HR, 1.12; 95% CI, 1.00-1.27) and men (HR, 1.26; 95% CI, 1.12-1.42). The association between waist/hip ratio and development of liver disease was independent of BMI. CONCLUSIONS: In a Swedish population-based cohort study, we associated all measures of body composition with risk of severe liver disease. However, measures of abdominal obesity were best at predicting development of severe liver disease.

  • 32.
    Andreasson, Anna N.
    et al.
    Stockholm University, Faculty of Social Sciences, Stress Research Institute. Karolinska Institutet, Sweden.
    Jones, M. P.
    Walker, M. M.
    Talley, N. J.
    Nyhlin, H.
    Agréus, L.
    Prediction pathways for innate immune pathology, IBS, anxiety and depression in a general population (The POPCOL Study)2013In: Brain, behavior, and immunity, ISSN 0889-1591, E-ISSN 1090-2139, Vol. 32, p. e46-e46Article in journal (Other academic)
    Abstract [en]

    The aim of this study was to ascertain whether low grade innate inflammation contributes to a pathway of depression and anxiety via irritable bowel syndrome (IBS). We evaluated innate immune cell counts in colonic mucosa in normal subjects and those with IBS (Rome III) from a population based study in which 745 randomly selected subjects had a colonoscopy (mean age 51 years;57% women). Intraepithelial lymphocytes (IELs) per 100 enterocytes and eosinophils (eos) per five non-overlapping high power fields (HPF) were counted in 90 controls and 100 cases; immunocytochemistry (CD117) was performed for mast cells per 5HPF in 80 controls and 81 cases. IELs, mast cells and eos were individually summed over 5 sites (terminal ileum, caecum, transverse colon, sigmoid colon and rectum). Anxiety and depression scores were calculated from HADS. A causal model path model which hypothesises immune cells being associated with IBS which, in turn, is associated with elevated anxiety and depression was tested using path analysis implemented in the MPlus software. All hypothesised paths reached statistical significance (p < .05) supporting the individual hypothesized pathways. The overall model fit was reasonable although imperfect. In conclusion, a significant contribution of innate immune inflammatory load leading to anxiety and depression via IBS was found. Whether therapy directed to decreasing this inflammatory load also lifts depression and anxiety should be further explored.

  • 33.
    Andreasson, Anna N.
    et al.
    Stockholm University, Faculty of Social Sciences, Stress Research Institute. Karolinska Institutet, Sweden.
    Schiller, Helena
    Stockholm University, Faculty of Social Sciences, Stress Research Institute.
    Kecklund, Göran
    Stockholm University, Faculty of Social Sciences, Stress Research Institute.
    Lekander, Mats
    Stockholm University, Faculty of Social Sciences, Stress Research Institute. Karolinska Institutet, Sweden.
    Contemplate your symptoms and re-evaluate your health2015In: Brain, behavior, and immunity, ISSN 0889-1591, E-ISSN 1090-2139, Vol. 49, p. e38-e39Article in journal (Refereed)
    Abstract [en]

    Bodily signals and how these are interpreted affect self-ratings of health. It is thus reasonable that appraisals of health are affected by imminent exposures and disease primes. We aimed to investigate whether self-ratings of health are affected by a symptom rating and if changes are substantiated in persons who report more symptoms. We used data from 813 persons who completed a questionnaire daily for 21 consecutive days. The questionnaire included a one-item self-rating of health (“pre-SRH”; 1 = excellent, 7 = very poor), a subsequent 26-item rating of physical and mental symptoms and thereafter a second (identical) self-rating of health (“post-SRH”). Paired t-tests were used to test for differences between pre-SRH and post-SRH. Mixed effect regression models were used to calculate the interaction effect of pre-SRH and symptom score on post-SRH adjusted for gender, age and if the person had been working that day (13545 observations). SRH worsened significantly (p  <<.0001) after the symptom rating, from 2.72 pre-SRH (95%CI:−2.70–2.74) to 2.77 post-SRH (95%CI:2.75–2.79). There was a significant interaction between pre-SRH and symptoms on post-SRH so that persons who reported more symptoms changed their post-SRH rating to a higher degree than those who reported fewer symptoms, irrespective of their subjective health status. The results support the notion that subjective health perception is affected by focus of attention, and that the effect depends on level of symptoms.

  • 34.
    Andreo, Pedro
    Stockholm University, Faculty of Science, Department of Physics. Karolinska Institutet, Sweden.
    Dose to 'water-like' media or dose to tissue in MV photons radiotherapy treatment planning: still a matter of debate2015In: Physics in Medicine and Biology, ISSN 0031-9155, E-ISSN 1361-6560, Vol. 60, no 1, p. 309-337Article in journal (Refereed)
    Abstract [en]

    The difference between Monte Carlo Treatment Planning (MCTP) based on the assumption of 'water-like' tissues with densities obtained from CT procedures, or on tissue compositions derived from CT-determined densities, have been investigated. Stopping powers and electron fluences have been calculated for a range of media and body tissues for 6 MV photon beams, including changes in their physical data (density and stopping powers). These quantities have been used to determine absorbed doses using cavity theory. It is emphasized that tissue compositions given in ICRU or ICRP reports should not be given the standing of physical constants as they correspond to average values obtained for a limited number of human-body samples. It has been shown that mass stopping-power ratios to water are more dependent on patient-to-patient composition differences, and therefore on their mean excitation energies (I-values), than on mass density. Electron fluence in different media are also more dependent on media composition (and their I-values) than on density. However, as a consequence of the balance between fluence and stopping powers, doses calculated from their product are more constant than what the independent stopping powers and fluence variations suggest. Additionally, cancelations in dose ratios minimize the differences between the 'water-like' and 'tissue' approaches, yielding practically identical results except for bone, and to a lesser extent for adipose tissue. A priori, changing from one approach to another does not seem to be justified considering the large number of approximations and uncertainties involved throughout the treatment planning tissue segmentation and dose calculation procedures. The key issue continues to be the composition of tissues and their I-values, and as these cannot be obtained for individual patients, whatever approach is selected does not lead to significant differences from a water reference dose, the maximum of these being of the order of 5% for bone tissues. Considering, however, current developments in advanced dose calculation methods, planning in terms of dose-to-tissue should be the preferred choice, under the expectancy that progress in the field will gradually improve some of the crude approximations included in MCTP and numerical transport methods. The small differences obtained also show that a retrospective conversion from dose-to-tissue to dose-to-water, based on a widely used approach, would mostly increase the final uncertainty of the treatment planning process. It is demonstrated that, due to the difference between electron fluence distributions in water and in body tissues, the conversion requires an additional fluence correction that has so far been neglected. An improved expression for the conversion and data for the fluence correction factor are provided. These will be necessary even in a dose-to-tissue environment, for the normalization of the treatment plan to the reference dosimetry of the treatment unit, always calibrated in terms of absorbed dose to water.

  • 35.
    Andreo, Pedro
    et al.
    Stockholm University, Faculty of Science, Department of Physics.
    Wulff, Joerg
    Burns, David T.
    Palmans, Hugo
    Consistency in reference radiotherapy dosimetry: resolution of an apparent conundrum when Co-60 is the reference quality for charged-particle and photon beams2013In: Physics in Medicine and Biology, ISSN 0031-9155, E-ISSN 1361-6560, Vol. 58, no 19, p. 6593-6621Article in journal (Refereed)
    Abstract [en]

    Substantial changes in ion chamber perturbation correction factors in Co-60 gamma-rays, suggested by recent Monte Carlo (MC) calculations, would cause a decrease of about 1.5% in the reference dosimetry of all types of charged particles (electrons, protons and heavier ions) based on calculated k(Q) values. It has gone largely unnoticed that the ratio of calibration coefficients N-D,N-w,N-Co60 and N-K,N-air,N-Co60 yields an experimental value of F-ch,F-Co60 = (s(w-air) pch)(Co60) through N-D,N-air,N-Co60. Coefficients provided by the IAEA and traceable to the BIPM for 91 NE-2571 chambers result in an average F-ch,F-Co60 which is compared with published (and new) MC simulations and with the value in IAEA TRS-398. It is shown that TRS-398 agrees within 0.12% with the experimental F-ch,F-Co60. The 1.5% difference resulting from MC calculations (1.1% for the new simulations) cannot be justified using current fundamental data and BIPM standards if consistency in the entire dosimetry chain is sought. For photons, MC k(Q) factors are compared with TRS-398. Using the same uncertainty for W-air, the two sets of data overlap considerably. Experimental k(Q) values from standards laboratories lie between the two sets of calculated values, showing no preference for one set over the other. Observed chamber-to-chamber differences, that include the effect of waterproof sleeves (also seen for Co-60), justify the recommendation in TRS-398 for k(Q) values specifically measured for the user chamber. Current developments on I-values for the stopping powers of water and graphite are presented. A weighted average I-water = 78 +/- 2 eV is obtained from published experimental and DRF-based values; this would decrease sw-air for all types of radiotherapy beams between 0.3% and 0.6%, and would consequently decrease the MC derived F-ch,F-Co60. The implications of a recent proposal for I-graphite = 81 eV are analysed, resulting in a potential decrease of 0.7% in N-K,N-air,N-Co60 which would raise the experimental F-ch,F-Co60; this would result in an increase of about 0.8% in the current TRS-398 value when referred to the BIPM standards. MC derived F-ch,F-Co60 using new stopping powers would then agree at a level of 0.1% with the experimental value, confirming the need for consistency in the dosimetry chain data. Should world average standards be used as reference, the figures would become +0.4% for TRS-398 and -0.3% for the MC calculation. F-ch,F-Q calculated for megavoltage photons using new stopping powers would decrease by between 0.2% and 0.5%. When they enter as a ratios in k(Q), differences with MC values based on current key data would be within 0.2% but their discrepancy with k(Q) experimental photon values remains unresolved. For protons the new data would require an increase in W-air,W-Q of about 0.6%, as this is inferred from a combination of calorimetry and ionometry. This consistent scenario would leave unchanged the current TRS-398 k(Q) (NE-2571) data for protons, as well as for ions heavier than protons unless new independent W-air,W-Q values become available. Also in these advanced radiotherapy modalities, the need for maintaining data consistency in an analysis that unavoidably must include the complete dosimetry chain is demonstrated.

  • 36.
    Andræ, Nils
    Stockholm University, Faculty of Science, Medical Radiation Physics (together with KI).
    Commissioning and validation of small subfields in Step-and-shoot IMRT2008Independent thesis Basic level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    One of the most used irradiation techniques in modern radiation therapy is step-and-shoot IMRT. The accuracy of this technique when delivering complex dose distributions strongly depends on the size of the subfields. The aims of this study is to determine the minimum size of subfields that can be used efficiently in Step-and-Shoot IMRT, to investigate the validation process for beam delivery and treatment planning dose calculations, and to find recommendations for practical clinical implementations.

    Two different detectors, a CC04 ion chamber and a SFD stereotactic diode, have been used for measuring head scatter factors in air (Sc), total output factors (Scp) and dose profiles in water for a wide range of field sizes. The measurements were compared to calculations done with a pre-release version of the Nucletron MasterPlanTM v 3.1 treatment planning system that employs a novel, high resolution fluence modelling for both its pencil beam and collapsed cone dose calculation algorithms. Collimator settings were explicitly checked using FWHM film measurements with a build-up sheet of tungsten placed close to the treatment head to reduce the influence from lateral electron transport and geometrical penumbra. An analysis of the influence and sensitivity of Scp for small fields with respect to the linear accelerator source size and shape was also made.

    The measurements with the ionization chamber and the stereotactic diode showed good agreements with each other and with the treatment planning system calculations for field sizes larger than 2×2 cm2. For small field sizes, measurements with different detectors yielded different results. Calculations showed agreements with measurements with the smallest detector, provided careful field size calibration and commissioning of calculation parameters. Uncertainties in collimator settings and source characteristics were shown to yield large uncertainties in Scp for fields smaller than 2×2 cm2.

    The treatment planning system was found to properly handle small subfields but results were very sensitive to uncertainties in source size, as well as calibration and reproducibility of the collimator settings. Therefore if subfields smaller than 2×2 cm2 are to be used in IMRT extra care should be taken to determine the source characteristics and to calibrate the collimators. The volume of the detectors used for validation of such small fields and the loss of charged particle equilibrium conditions also have to be taken into consideration.

  • 37.
    Anghammar, Fredrik
    Stockholm University, Faculty of Social Sciences, Department of Psychology.
    Psykologiska bedömningar inför arbete med föräldrar inom BUP2010Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [sv]

    Psykologiska bedömningar av föräldrar beskrivs sällan som en mer uttalad och tydlig del av arbetet inom barn- och ungdomspsykiatri, utan det är i hög grad ett underförstått arbetsområde. Syftet med den här undersökningen var att beskriva hur arbetet med psykologiska bedömningar av föräldrar konceptualiseras och praktiseras under det inledande skedet av behandlingskontakter inom BUP. Nio psykologer vid sju öppenvårdsmottagningar intervjuades och intervjuerna analyserades tematiskt. En viktig aspekt som framkommer i resultatet är hur det gemensamma arbetet mellan psykolog och förälder för att etablera en arbetsallians erbjuder goda möjligheter till psykologiska bedömningar av föräldern. Under arbetet med alliansen, och med alliansen som bas, kan olika former av systematik och modeller för psykologiska bedömningar tillämpas. Resultatet indikerar också att arbetsalliansens centrala betydelse för bedömningsarbetet är tydligt relaterad till organisationens påverkan på det arbetet, liksom till betydelsen av psykologisk kompetens vid arbete med psykologiska bedömningar av föräldrar.

  • 38.
    Angleman, Sara B.
    et al.
    Stockholm University, Faculty of Social Sciences, Aging Research Center (ARC), (together with KI). Stockholm Gerontology Research Center, Sweden.
    Santoni, Giola
    Stockholm University, Faculty of Social Sciences, Aging Research Center (ARC), (together with KI).
    Von Strauss, Eva
    Stockholm University, Faculty of Social Sciences, Aging Research Center (ARC), (together with KI). The Swedish Red Cross University College, Sweden.
    Fratiglioni, Laura
    Stockholm University, Faculty of Social Sciences, Aging Research Center (ARC), (together with KI). The Swedish Red Cross University College, Sweden.
    Temporal Trends of Functional Dependence and Survival Among Older Adults From 1991 to 2010 in Sweden: Toward a Healthier Aging2015In: The journals of gerontology. Series A, Biological sciences and medical sciences, ISSN 1079-5006, E-ISSN 1758-535X, Vol. 70, no 6, p. 746-752Article in journal (Refereed)
    Abstract [en]

    Background. Declines in functional dependence among older adults were observed before the 1990s, but there is uncertainty about subsequent trends. Our study aimed to verify the temporal trends in disability during 1991-2010 in an older Swedish population and to estimate the associated changes in survival. Methods. Functional status in octogenarians and nonagenarians was assessed at seven occasions with intervals of 2-3 years. Sample size varied at each assessment with an average of 646 (range 212-1096). Disability was defined as difficulty in one or more of personal activities of daily living. We compared prevalence and incidence, as well as mortality, and survival associated with disability over the 20-year period. Results. Sex-standardized prevalence of disability remained steady over time with a tendency toward a gradual decline, and a statistically significant decrease was present among nonagenarians. Sex-standardized cumulative incidence also remained steady. The proportion of people with prevalent disability who died <3 years remained stable, as did the survival time of people with incident disability. In contrast, among nondisabled persons, 3-year mortality decreased significantly, and for octogenarians median survival time was 1.3 years longer at the more recent assessment than a decade earlier. Conclusions. Both prevalence and incidence of disability remained stable over the last two decades in this urban Swedish population, with a trend toward a slow decline. Mortality remained steady among disabled persons but decreased among persons without disability, suggesting that increased life expectancy during the last two decades may be essentially driven by longer lives of functionally independent people.

  • 39. Anisimov, Vladimir N.
    et al.
    Egorov, Maxim V.
    Krasilshchikova, Marina S.
    Lyamzaev, Konstantin G.
    Manskikh, Vasily N.
    Moshkin, Mikhail P.
    Novikov, Evgeny A.
    Popovich, Irina G.
    Rogovin, Konstantin A.
    Shabalina, Irina G.
    Stockholm University, Faculty of Science, The Wenner-Gren Institute , Physiology.
    Shekarova, Olga N.
    Skulachev, Maxim V.
    Titova, Tatiana V.
    Vygodin, Vladimir A.
    Vyssokikh, Mikhail Yu.
    Yurova, Maria N.
    Zabezhinsky, Mark A.
    Skulachev, Vladimir P.
    Effects of the mitochondria-targeted antioxidant SkQ1 on lifespan of rodents2011In: Aging, ISSN 1945-4589, E-ISSN 1945-4589, Vol. 3, no 11, p. 1110-1119Article in journal (Refereed)
    Abstract [en]

    The effect of the mitochondria-targeted, plastoquinone-containing antioxidant SkQ1 on the lifespan of outbred mice and of three strains of inbred mice was studied. To this end, low pathogen (LP) or specific pathogen free (SPF) vivaria in St. Petersburg, Moscow, and Stockholm were used. For comparison, we also studied mole-voles and dwarf hamsters, two wild species of small rodents kept under simulated natural conditions. It was found that substitution of a LP vivarium for a conventional (non-LP) one doubled the lifespan of female outbred mice, just as SkQ1 did in a non-LP vivarium. SkQ1 prevented age-dependent disappearance of estrous cycles of outbred mice in both LP and non-LP vivaria. In the SPF vivarium in Moscow, male BALB/c mice had shorter lifespan than females, and SkQ1 increased their lifespan to the values of the females. In the females, SkQ1 retarded development of such trait of aging as heart mass increase. Male C57Bl/6 mice housed individually in the SPF vivarium in Stockholm lived as long as females. SkQ1 increased the male lifespan, the longevity of the females being unchanged. SkQ1 did not change food intake by these mice. Dwarf hamsters and mole-voles kept in outdoor cages or under simulated natural conditions lived longer if treated with SkQ1. The effect of SkQ1 on longevity of females is assumed to mainly be due to retardation of the age-linked decline of the immune system. For males under LP or SPF conditions, SkQ1 increased the lifespan, affecting also some other system(s) responsible for aging.

  • 40.
    Antonovic, Laura
    Stockholm University, Faculty of Science, Medical Radiation Physics (together with KI).
    Evaluation of the lithium formate EPR dosimetry system for dose measurements around 192Ir brachytherapy sources2008Independent thesis Basic level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The dose distribution around brachytherapy (BT) sources is characterized by steep dose gradients and an energy spectrum varying rapidly with depth in water around the source. These two properties make experimental verification of the dose distribution difficult, and put high demands on the dosimetry system in use regarding precision, size and energy dependence. The American Association of Physicists in Medicine (AAPM) recommends lithium fluoride (LiF) thermo-luminescence dosimetry (TLD) to be used for verification measurements, as it is the only dosimetry system meeting the requirements, but still the total combined uncertainty in dose-rate determination is as high as 7-9 % (1 σ). Lithium formate is a new dosimetry material that is less energy dependent than LiF, but more sensitive than the most common EPR (electron paramagnetic resonance) dosimetry material, alanine. In order to evaluate lithium formate EPR for BT dosimetry, dosimeters were produced for experimental dose determination around BT source 192Ir. The dosimeters were calibrated against an ionization chamber in a high energy photon beam. Dose to water was determined at 1, 3 and 5 cm radial distance from the source, which was stepped along a straight line in a PMMA phantom. The experiments were performed twice using 4 dosimeters per distance and experiment. Methods to correct for energy dependence were developed and evaluated. The uncertainty in measured dose was estimated. The experimental dose values agreed with the values from the treatment planning system with a maximum deviation of 3.3 %, and an average 1 σ uncertainty of 3 % at 3 and 5 cm and 5 % at 1cm. Uncertainty in radial distance from the source as well as source calibration were the dominating contributions to the total combined uncertainty. Lithium formate EPR has been shown to be a promising alternative to LiF TLD for BT dosimetry.

  • 41.
    Antonovic, Laura
    et al.
    Stockholm University, Faculty of Science, Department of Physics. Karolinska Institutet, Sweden.
    Brahme, Anders
    Furusawa, Yoshiya
    Toma-Dasu, Iuliana
    Stockholm University, Faculty of Science, Department of Physics. Karolinska Institutet, Sweden.
    Radiobiological description of the LET dependence of the cell survival of oxic and anoxic cells irradiated by carbon ions2013In: Journal of radiation research, ISSN 0449-3060, E-ISSN 1349-9157, Vol. 54, no 1, p. 18-26Article in journal (Refereed)
    Abstract [en]

    Light-ion radiation therapy against hypoxic tumors is highly curative due to reduced dependence on the presence of oxygen in the tumor at elevated linear energy transfer (LET) towards the Bragg peak. Clinical ion beams using spread-out Bragg peak (SOBP) are characterized by a wide spectrum of LET values. Accurate treatment optimization requires a method that can account for influence of the variation in response for a broad range of tumor hypoxia, absorbed doses and LETs. This paper presents a parameterization of the Repairable Conditionally-Repairable (RCR) cell survival model that can describe the survival of oxic and hypoxic cells over a wide range of LET values, and investigates the relationship between hypoxic radiation resistance and LET. The biological response model was tested by fitting cell survival data under oxic and anoxic conditions for V79 cells irradiated with LETs within the range of 30 – 500 keV/μm. The model provides good agreement with experimental cell survival data for the range of LET investigated, confirming the robustness of the parameterization method. This new version of the RCR model is suitable for describing the biological response of mixed populations of oxic and hypoxic cells and at the same time taking into account the distribution of doses and LETs in the incident beam and its variation with depth in tissue. The model offers a versatile tool for the selection of LET and dose required in the optimization of the therapeutic effect, without severely affecting normal tissue in realistic tumors presenting highly heterogeneous oxic and hypoxic regions.

  • 42.
    Antonovic, Laura
    et al.
    Stockholm University, Faculty of Science, Department of Physics.
    Lindblom, Emely
    Stockholm University, Faculty of Science, Department of Physics.
    Dasu, Alexandru
    Bassler, Niels
    Furusawa, Yoshiya
    Toma-Dasu, Iuliana
    Stockholm University, Faculty of Science, Department of Physics. Karolinska Institutet, Sweden.
    Clinical oxygen enhancement ratio of tumors in carbon ion radiotherapy: the influence of local oxygenation changes2014In: Journal of radiation research, ISSN 0449-3060, E-ISSN 1349-9157, Vol. 55, no 5, p. 902-911Article in journal (Refereed)
    Abstract [en]

    The effect of carbon ion radiotherapy on hypoxic tumors has recently been questioned because of low linear energy transfer (LET) values in the spread-out Bragg peak (SOBP). The aim of this study was to investigate the role of hypoxia and local oxygenation changes (LOCs) in fractionated carbon ion radiotherapy. Three-dimensional tumors with hypoxic subvolumes were simulated assuming interfraction LOCs. Different fractionations were applied using a clinically relevant treatment plan with a known LET distribution. The surviving fraction was calculated, taking oxygen tension, dose and LET into account, using the repairable–conditionally repairable (RCR) damage model with parameters for human salivary gland tumor cells. The clinical oxygen enhancement ratio (OER) was defined as the ratio of doses required for a tumor control probability of 50% for hypoxic and well-oxygenated tumors. The resulting OER was well above unity for all fractionations. For the hypoxic tumor, the tumor control probability was considerably higher if LOCs were assumed, rather than static oxygenation. The beneficial effect of LOCs increased with the number of fractions. However, for very low fraction doses, the improvement related to LOCs did not compensate for the increase in total dose required  for tumor control. In conclusion, our results suggest that hypoxia can influence the outcome of carbon ion radiotherapy because of the non-negligible oxygen effect at the low LETs in the SOBP. However, if LOCs occur, a relatively high level of tumor control probability is achievable with a large range of fractionation schedules for tumors with hypoxic subvolumes, but both hyperfractionation and hypofractionation should be pursued with caution.

  • 43. Arama, Charles
    et al.
    Skinner, Jeff
    Doumtabe, Didier
    Portugal, Silvia
    Tran, Tuan M.
    Jain, Aarti
    Traore, Boubacar
    Doumbo, Ogobara K.
    Davies, David Huw
    Troye-Blomberg, Marita
    Stockholm University, Faculty of Science, The Wenner-Gren Institute, Immunology.
    Dolo, Amagana
    Felgner, Philip L.
    Crompton, Peter D.
    Genetic Resistance to Malaria Is Associated With Greater Enhancement of Immunoglobulin (Ig)M Than IgG Responses to a Broad Array of Plasmodium falciparum Antigens2015In: Open forum infectious diseases, ISSN 2328-8957, Vol. 2, no 3Article in journal (Refereed)
    Abstract [en]

    Background. People of the Fulani ethnic group are more resistant to malaria compared with genetically distinct ethnic groups, such as the Dogon people, in West Africa, and studies suggest that this resistance is mediated by enhanced antibody responses to Plasmodium falciparum antigens. However, prior studies measured antibody responses to < 0.1% of P falciparum proteins, so whether the Fulani mount an enhanced and broadly reactive immunoglobulin (Ig) M and IgG response to P falciparum remains unknown. In general, little is known about the extent to which host genetics influence the overall antigen specificity of IgM and IgG responses to natural infections. Methods. In a cross-sectional study in Mali, we collected plasma from asymptomatic, age-matched Fulani (n = 24) and Dogon (n = 22) adults with or without concurrent P falciparum infection. We probed plasma against a protein microarray containing 1087 P falciparum antigens and compared IgM and IgG profiles by ethnicity. Results. We found that the breadth and magnitude of P falciparum-specific IgM and IgG responses were significantly higher in the malaria-resistant Fulani versus the malaria-susceptible Dogon, and, unexpectedly, P falciparum-specific IgM responses more strongly distinguished the 2 ethnic groups. Conclusions. These findings point to an underappreciated role for IgM in protection from malaria, and they suggest that host genetics may influence the antigen specificity of IgM and IgG responses to infection.

  • 44.
    Arat, Arzu
    et al.
    Stockholm University, Faculty of Social Sciences, Centre for Health Equity Studies (CHESS). Karolinska Institute, Sweden.
    Östberg, Viveca
    Stockholm University, Faculty of Social Sciences, Centre for Health Equity Studies (CHESS).
    Burström, Bo
    Hjern, Anders
    Stockholm University, Faculty of Social Sciences, Centre for Health Equity Studies (CHESS). Karolinska Institute, Sweden.
    ADHD medication in offspring of immigrants - does the income level of the country of parental origin matter?2018In: BMC Psychiatry, ISSN 1471-244X, E-ISSN 1471-244X, Vol. 18, no 1, article id 3Article in journal (Refereed)
    Abstract [en]

    BACKGROUND: Child psychiatric treatment facilities vary greatly worldwide and are virtually non-existent in many low-income countries. One of the most common psychiatric disorders in childhood is ADHD, with an estimated prevalence of 3-5% in Sweden. Previous studies have shown a similar prevalence of ADHD in minority and majority children in Sweden and the UK. However, clinical studies demonstrated that children from immigrant families living in Sweden received less psychiatric care than those of native-born parents. We tested the hypothesis that the consumption of child psychiatric care in immigrant families would be determined by the availability of such treatment in the parents' country of origin. Patterns of medication for attention-deficit hyperactivity disorder (ADHD) were studied as a proxy for child psychiatric care.

    METHODS: This was a register study of dispensed stimulant medication during 2013-2014 in Swedish national birth cohorts from 1995-2009. The study population, consisting of nearly 1.4 million children, was divided by national income of the parental country of origin and whether the parents were native Swedes, European immigrants, non-European immigrants or a mixture. Logistic regression was used to calculate the odds ratios of having been dispensed at least one ADHD drug during 2013, with adjustments for gender, family status indicating whether the child is living with both parents, household income and area of residence.

    RESULTS: Having parents born in low-income (OR [95% confidence interval] 0.27 [0.24-0.29]) or middle-income (European: OR 0.23 [0.20-0.26], non-European: OR 0.39 [0.34-0.41]) countries was associated with lower ADHD treatment levels than having parents born in high-income countries (European: OR 0.60 [0.54-0.66], non-European: OR 0.68 [0.59-0.79]), when compared to children of parents born in Sweden. In families with a background in low or middle income countries, there was no significant association between household income and ADHD medication, while in children with Swedish and mixed backgrounds high level of disposable income was associated with lower levels of ADHD medication.

    CONCLUSION: The use of child psychiatric care by immigrant families in Sweden was largely associated with the income level of the country of origin.

  • 45.
    Ardenfors, Oscar
    et al.
    Stockholm University, Faculty of Science, Department of Physics.
    Dasu, Alexandru
    Lillhök, Jan
    Persson, Linda
    Gudowska, Irena
    Stockholm University, Faculty of Science, Department of Physics.
    Out-of-field doses from secondary radiation produced in proton therapy and the associated risk of radiation-induced cancer from a brain tumor treatment2018In: Physica medica (Testo stampato), ISSN 1120-1797, E-ISSN 1724-191X, Vol. 53, p. 129-136Article in journal (Refereed)
    Abstract [en]

    Purpose

    To determine out-of-field doses produced in proton pencil beam scanning (PBS) therapy using Monte Carlo simulations and to estimate the associated risk of radiation-induced second cancer from a brain tumor treatment.

    Methods

    Simulations of out-of-field absorbed doses were performed with MCNP6 and benchmarked against measurements with tissue-equivalent proportional counters (TEPC) for three irradiation setups: two irradiations of a water phantom using proton energies of 78-147 MeV and 177-223 MeV, and one brain tumor irradiation of a whole-body phantom. Out-of-field absorbed and equivalent doses to organs in a whole-body phantom following a brain tumor treatment were subsequently simulated and used to estimate the risk of radiation-induced cancer. Additionally, the contribution of absorbed dose originating from radiation produced in the nozzle was calculated from simulations.

    Results

    Out-of-field absorbed doses to the TEPC ranged from 0.4 to 135 mu Gy/Gy. The average deviation between simulations and measurements of the water phantom irradiations was about 17%. The absorbed dose contribution from radiation produced in the nozzle ranged between 0 and 70% of the total dose; the contribution was however small in absolute terms. The absorbed and equivalent doses to the organs ranged between 0.2 and 60 mu Gy/Gy and 0.5-151 mu Sv/Gy. The estimated lifetime risk of radiation-induced second cancer was approximately 0.01%.

    Conclusions

    The agreement of out-of-field absorbed doses between measurements and simulations was good given the sources of uncertainties. Calculations of out-of-field organ doses following a brain tumor treatment indicated that proton PBS therapy of brain tumors is associated with a low risk of radiation-induced cancer.

  • 46.
    Ardenfors, Oscar
    et al.
    Stockholm University, Faculty of Science, Department of Physics.
    Gudowska, Irena
    Stockholm University, Faculty of Science, Department of Physics.
    Flejmer, Anna Maria
    Dasu, Alexandru
    IMPACT OF IRRADIATION SETUP IN PROTON SPOT SCANNING BRAIN THERAPY ON ORGAN DOSES FROM SECONDARY RADIATION2018In: Radiation Protection Dosimetry, ISSN 0144-8420, E-ISSN 1742-3406, Vol. 180, no 1-4, p. 261-266Article in journal (Refereed)
    Abstract [en]

    A Monte Carlo model of a proton spot scanning pencil beam was used to simulate organ doses from secondary radiation produced from brain tumour treatments delivered with either a lateral field or a vertex field to one adult and one paediatric patient. Absorbed doses from secondary neutrons, photons and protons and neutron equivalent doses were higher for the vertex field in both patients, but the differences were low in absolute terms. Absorbed doses ranged between 0.1 and 43 mu Gy. Gy(-1) in both patients with the paediatric patient receiving higher doses. The neutron equivalent doses to the organs ranged between 0.5 and 141 mu Sv. Gy(-1) for the paediatric patient and between 0.2 and 134 mu Sv. Gy(-1) for the adult. The highest neutron equivalent dose from the entire treatment was 7 mSv regardless of field setup and patient size. The results indicate that different field setups do not introduce large absolute variations in out-of-field doses produced in patients undergoing proton pencil beam scanning of centrally located brain tumours.

  • 47.
    Ardenfors, Oscar
    et al.
    Stockholm University, Faculty of Science, Department of Physics.
    Henry, Thomas
    Stockholm University, Faculty of Science, Department of Physics.
    Gudowska, Irena
    Stockholm University, Faculty of Science, Department of Physics.
    Poludniowski, Gavin
    Dasu, Alexandru
    Organ doses from a proton gantry-mounted cone-beam computed tomography system characterized with MCNP6 and GATE2018In: Physica medica (Testo stampato), ISSN 1120-1797, E-ISSN 1724-191X, Vol. 53, p. 56-61Article in journal (Refereed)
    Abstract [en]

    Purpose

    To determine organ doses from a proton gantry-mounted cone-beam computed tomography (CBCT) system using two Monte Carlo codes and to study the influence on organ doses from different acquisition modes and repeated imaging.

    Methods

    The CBCT system was characterized with MCNP6 and GATE using measurements of depth doses in water and spatial profiles in air. The beam models were validated against absolute dose measurements and used to simulate organ doses from CBCT imaging with head, thorax and pelvis protocols. Anterior and posterior 190° scans were simulated and the resulting organ doses per mAs were compared to those from 360° scans. The influence on organ doses from repeated imaging with different imaging schedules was also investigated.

    Results

    The agreement between MCNP6, GATE and measurements with regard to depth doses and beam profiles was within 4% for all protocols and the corresponding average agreement in absolute dose validation was 4%. Absorbed doses for in-field organs from 360° scans ranged between 6 and 8 mGy, 15–17 mGy and 24–54 mGy for the head, thorax and pelvis protocols, respectively. Cumulative organ doses from repeated CBCT imaging ranged between 0.04 and 0.32 Gy for weekly imaging and 0.2–1.6 Gy for daily imaging. The anterior scans resulted in an average increase in dose per mAs of 24% to the organs of interest relative to the 360° scan, while the posterior scan showed a 37% decrease.

    Conclusions

    A proton gantry-mounted CBCT system was accurately characterized with MCNP6 and GATE. Organ doses varied greatly depending on acquisition mode, favoring posterior scans.

  • 48.
    Ardenfors, Oscar
    et al.
    Stockholm University, Faculty of Science, Department of Physics. Linköping University, Sweden; Karolinska Institutet, Sweden.
    Josefsson, Dan
    Dasu, Alexandru
    Are IMRT treatments in the head and neck region increasing the risk of secondary cancers?2014In: Acta Oncologica, ISSN 0284-186X, E-ISSN 1651-226X, Vol. 53, no 8, p. 1041-1047Article in journal (Refereed)
    Abstract [en]

    Background. Intensity-modulated radiation therapy (IMRT) has been increasingly employed for treating head and neck (H&N) tumours due to its ability to produce isodoses suitable for the complex anatomy of the region. The aim of this study was to assess possible differences between IMRT and conformal radiation therapy (CRT) with regard to risk of radiation-induced secondary malignancies for H&N tumours. Material and methods. IMRT and CRT plans were made for 10 H&N adult patients and the resulting treatment planning data were used to calculate the risk of radiation-induced malignancies in four different tissues. Three risk models with biologically relevant parameters were used for calculations. The influence of scatter radiation and repeated imaging sessions has also been investigated. Results. The results showed that the total lifetime risks of developing radiation-induced secondary malignancies from the two treatment techniques, CRT and IMRT, were comparable and in the interval 0.9-2.5%. The risk contributions from the primary beam and scatter radiation were comparable, whereas the contribution from repeated diagnostic imaging was considerably smaller. Conclusion. The results indicated that the redistribution of the dose characteristic to IMRT leads to a redistribution of the risks in individual tissues. However, the total levels of risk were similar between the two irradiation techniques considered.

  • 49. Arentsen, T.
    et al.
    Qian, Y.
    Gkotzis, Spyridon
    Stockholm University, Faculty of Science, Department of Molecular Biosciences, The Wenner-Gren Institute. Karolinska Institutet, Sweden.
    Femenia, T.
    Wang, T.
    Udekwu, Klas
    Stockholm University, Faculty of Science, Department of Molecular Biosciences, The Wenner-Gren Institute.
    Forssberg, H.
    Heijtz, R. Diaz
    The bacterial peptidoglycan-sensing molecule Pglyrp2 modulates brain development and behavior2017In: Molecular Psychiatry, ISSN 1359-4184, E-ISSN 1476-5578, Vol. 22, no 2, p. 257-266Article in journal (Refereed)
    Abstract [en]

    Recent studies have revealed that the gut microbiota modulates brain development and behavior, but the underlying mechanisms are still poorly understood. Here, we show that bacterial peptidoglycan (PGN) derived from the commensal gut microbiota can be translocated into the brain and sensed by specific pattern-recognition receptors (PRRs) of the innate immune system. Using expression-profiling techniques, we demonstrate that two families of PRRs that specifically detect PGN (that is, PGN-recognition proteins and NOD-like receptors), and the PGN transporter PepT1 are highly expressed in the developing brain during specific windows of postnatal development in both males and females. Moreover, we show that the expression of several PGN-sensing molecules and PepT1 in the developing striatum is sensitive to manipulations of the gut microbiota (that is, germ-free conditions and antibiotic treatment). Finally, we used the PGN-recognition protein 2 (Pglyrp2) knockout mice to examine the potential influence of PGN-sensing molecules on brain development and behavior. We demonstrate that the absence of Pglyrp2 leads to alterations in the expression of the autism risk gene c-Met, and sex-dependent changes in social behavior, similar to mice with manipulated microbiota. These findings suggest that the central activation of PRRs by microbial products could be one of the signaling pathways mediating the communication between the gut microbiota and the developing brain.

  • 50.
    Arnberg, Filip K.
    et al.
    Stockholm University, Faculty of Social Sciences, Stress Research Institute. Uppsala University, Sweden.
    Gudmundsdóttir, Ragnhildur
    Butwicka, Agnieszka
    Fang, Fang
    Lichtenstein, Paul
    Hultman, Christina M.
    Valdimarsdóttir, Unnur A.
    Psychiatric disorders and suicide attempts in Swedish survivors of the 2004 southeast Asia tsunami: a 5 year matched cohort study2015In: Lancet psychiatry, ISSN 2215-0374, E-ISSN 2215-0366, Vol. 2, no 9, p. 817-824Article in journal (Refereed)
    Abstract [en]

    Background: Survivors of natural disasters are thought to be at an increased risk of psychiatric disorders, however the extent of this risk, and whether it is linked to pre-existing psychopathology, is not known. We aimed to establish whether Swedish survivors of tsunamis from the 2004 Sumatra-Andaman earthquake had increased risks of psychiatric disorders and suicide attempts 5 years after repatriation.

    Methods: We identified Swedish survivors repatriated from southeast Asia (8762 adults and 3742 children) and 864 088 unexposed adults and 320 828 unexposed children matched for sex, age, and socioeconomic status. We retrieved psychiatric diagnoses and suicide attempts from the Swedish patient register for the 5 years after the tsunami (from Dec 26, 2004, to Jan 31, 2010) and estimated hazard ratios (HRs), then adjusted for pre-tsunami psychiatric disorders, and, for children, for parental pre-tsunami disorders.

    Findings: Exposed adults were more likely than unexposed adults to receive any psychiatric diagnosis (547 [6.2%] vs 47 734 [5.5%]; adjusted HR 1.21, 95% CI 1.11-1.32), particularly stress-related disorders (187 [2.1%] vs 8831 [1.0%]; 2.27, 1.96-2.62) and suicide attempts (38 [0.43%] vs 2752 [0.32%]; 1.54, 1.11-2.13), but not mood or anxiety disorders. Risk of psychiatric diagnoses did not differ between exposed and unexposed children and adolescents (248 [6.6] vs 22 081 [6.9%]; 0.98, 0.86-1.11), although exposed children and adolescents had a higher risk for suicide attempts with uncertain intent (1.43; 1.01-2.02) and stress-related disorders (1.79; 1.30-2.46), mainly during the first 3 months after the tsunami.

    Interpretation: The 2004 tsunami was, independently of previous psychiatric morbidity, associated with an increased risk of severe psychopathology, mainly stress-related disorders and suicide attempts, in children and adults. Survivors of natural disasters should be targeted with early interventions and active long-term follow-up to prevent, detect, and alleviate psychiatric disorders that might follow.

    Funding: The Swedish Council for Working Life and Social Research, Swedish Board of Health and Welfare, Polish Ministry of Science and Higher Education, Swedish Society for Medical Research.

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