| 41. |
- Gatz, Margaret, et al.
(författare)
-
Dementia : Genes, environments, interactions
- 2014
-
Ingår i: Behavior genetics of cognition across the lifespan. - New York : Springer. - 9781461474470 - 9781461474463 ; , s. 201-231
-
Bokkapitel (refereegranskat)abstract
- Dementia is an increasingly prevalent disorder as the world population ages, with Alzheimer disease the most common cause. Twin studies find concordance to be substantially higher among monozygotic as compared with dizygotic twin pairs. While a few genes have been identified that are responsible for early-onset Alzheimer disease, they account for well under 5 % of all cases. Among susceptibility genes for Alzheimer disease identified by association studies, population attributable fraction for the most prominent of these—apolipoprotein E—is estimated to be about 25 %, whereas other genes at best predict another 20 %. There are few strong environmental risk or protective factors, with vascular risks the best established, although with mechanisms still not fully understood. It seems likely that clusters of risk alleles, interactions between risk alleles and environmental exposures, and epigenetic mechanisms play a role in explaining Alzheimer disease, with different combinations of influences culminating in the observed pathophysiology. In particular, environmental exposures early in life could lead to deleterious changes in gene expression in late life.
|
|
| 42. |
- Gustafsson, Ida, et al.
(författare)
-
Breastfeeding and experienced exposedness in partner relationshiop
- 2023
-
Ingår i: Abstract Book The Nordic Breastfeeding Conference 2023.
-
Konferensbidrag (refereegranskat)abstract
- BREASTFEEDING AND EXPERIENCED EXPOSEDNESS IN PARTNER RELATIONSHIPIda Gustafsson RN, RM, Lecturer, PhD-studentFaculty of Caring Science, Work Life and Social Welfare, University of Borås, Borås, SwedenGunilla Carlsson RN, PhD, ProfessorFaculty of Caring Science, Work Life and Social Welfare, University of Borås, Borås, SwedenKatarina Karlsson RN, PhDFaculty of Caring Science, Work Life and Social Welfare, University of Borås, Borås, SwedenAleksandra Jarling RN, PhD, LecturerFaculty of Caring Science, Work Life and Social Welfare, University of Borås, Borås, SwedenLina Palmér RN, RM, PhD, Associate Professor, DocentFaculty of Caring Science, Work Life and Social Welfare, University of Borås, Borås, Sweden Background: About 110 000 children are born in Sweden annually. The vast majority of their mothers wish to breastfeed, and also initiate breastfeeding. An important factor for continued breastfeeding is support, especially from the partner. It is likely that lack of support can lead to perceived vulnerability in the partner relationship. Intimate partner violence (IPV) during pregnancy is in Sweden nearly as common as gestational diabetes and the frequency seems to rise postpartum. IPV is multifaceted and encompasses many types and degrees of violence. In a caring science perspective the experience of vulnerability and/or exposedness in partner relationship during breastfeeding (or breastfeeding desire) risks negatively affecting womens health and well-being, regardless of the reason or degree of exposedness. For care to be caring - that is, support health and well-being - knowledge is needed from the perspective of the exposed women. Previous lifeworld theoretical research has shown that breastfeeding may be experienced as an existential challenge and that exposedness to violence during the childbearing period means a long-lasting embodied experience. In this project, these two phenomena are intertwined into a common phenomenon - Breastfeeding in case of experienced exposedness in a partner relationship. Aim: The purpose of the PhD-project is to develop in-depth knowledge of existential meanings of breastfeeding in case of experienced exposedness in a partner relationship (Study 1-2), and what it means to be cared for (Study 3), as well as to give care and support in this context (Study 4). Methods: The project has a reflective lifeworld approach. Data has been collected through lifeworld interviews and written lifeworld stories and will be analyzed using a phenomenological or hermeneutical approach. Results & Conclusion: The results and conclusions of the first study are expected to be completed in the summer of 2023 and will be presented at the conference.
|
|
| 43. |
|
|
| 44. |
- Holmberg, Jenny, et al.
(författare)
-
Exploring motives and perceived barriers for voice modification : the views of transgender and gender-diverse voice clients
- 2023
-
Ingår i: Journal of Speech, Language and Hearing Research. - : American Speech Language Hearing Association. - 1092-4388 .- 1558-9102. ; 66:7, s. 2246-2259
-
Tidskriftsartikel (refereegranskat)abstract
- Purpose: To date, transgender and gender-diverse voice clients' perceptions and individual goals have been missing in discussions and research on gender-affirming voice therapy. Little is, therefore, known about the client's expectations of therapy outcomes and how these are met by treatments developed from views of vocal gender as perceived by cisgender persons. This study aimed to explore clients' individual motives and perceived barriers to undertaking gender-affirming voice therapy.Method: Individual, semistructured interviews with 15 transgender and gender-diverse voice clients considering voice therapy were conducted and explored using qualitative content analysis.Results: Three themes were identified during the analysis of the participants' narratives. In the first theme, “the incongruent voice setting the rules,” the contribution of the voice on the experienced gender dysphoria is put in focus. The second theme, “to reach a voice of my own choice,” centers around anticipated personal gains using a modified voice. The third theme, “a voice out of reach,” relates to worries and restricting factors for not being able to reach one's set goals for voice modification.Conclusions: The interviews clearly indicate a need for a person-centered voice therapy that starts from the individuals' expressed motives for modifying the voice yet also are affirmative of anticipated difficulties related to voice modification. We recommend that these themes should form the basis of the pretherapy joint discussion between the voice client and the speech-language pathologist to ensure therapy goals that are realistic and relevant to the client.
|
|
| 45. |
- Holmberg, Jenny, et al.
(författare)
-
Perception of femininity and masculinity in voices as rated by transgender and gender diverse people, professional speech and language pathologists, and cisgender naive listeners
- 2024
-
Ingår i: Journal of Voice. - : Elsevier. - 0892-1997 .- 1873-4588.
-
Tidskriftsartikel (refereegranskat)abstract
- Objective: To explore whether cisgender naive listeners, transgender and gender diverse (TGD) listeners, and speech-language pathologists (SLPs) experienced in providing gender-affirming voice training differ in their perception of femininity and masculinity in voices.Methods: Samples of spontaneous speech were collected from 95 cisgender, and 37 TGD speakers. Three listener groups of cisgender naive (N = 77), TGD (N = 30), and SLP (N = 14) listeners, respectively, rated the voices on visual analog scales in two randomly ordered blocks, in which the perceived degree of femininity was rated separately from the perceived degree of masculinity.Results: The three listener groups showed similar patterns in their distribution of ratings on the femininity and masculinity scales. The TGD listeners’ mean ratings did not differ from the cisgender naive listeners’, whereas SLPs showed a small, but significant, difference in their ratings compared with both TGD and cisgender naive listeners and rated the voices lower on both the femininity and masculinity scales.Conclusion: The results differ from previous studies as TGD, and cisgender naive listeners rated the voices very similarly. The lower ratings of femininity and masculinity by the SLPs were likely influenced by their awareness of the complexity in the perception of voices. Therefore, SLPs providing gender-affirming voice training should be attentive to how their professional training may influence their perception of femininity and masculinity in voices and encourage discussions and explorations of the TGD voice client's perceptions of voices.
|
|
| 46. |
- Hou, JH, et al.
(författare)
-
Polygenic resilience scores capture protective genetic effects for Alzheimer's disease
- 2022
-
Ingår i: Translational psychiatry. - : Springer Science and Business Media LLC. - 2158-3188. ; 12:1, s. 296-
-
Tidskriftsartikel (refereegranskat)abstract
- Polygenic risk scores (PRSs) can boost risk prediction in late-onset Alzheimer’s disease (LOAD) beyond apolipoprotein E (APOE) but have not been leveraged to identify genetic resilience factors. Here, we sought to identify resilience-conferring common genetic variants in (1) unaffected individuals having high PRSs for LOAD, and (2) unaffected APOE-ε4 carriers also having high PRSs for LOAD. We used genome-wide association study (GWAS) to contrast “resilient” unaffected individuals at the highest genetic risk for LOAD with LOAD cases at comparable risk. From GWAS results, we constructed polygenic resilience scores to aggregate the addictive contributions of risk-orthogonal common variants that promote resilience to LOAD. Replication of resilience scores was undertaken in eight independent studies. We successfully replicated two polygenic resilience scores that reduce genetic risk penetrance for LOAD. We also showed that polygenic resilience scores positively correlate with polygenic risk scores in unaffected individuals, perhaps aiding in staving off disease. Our findings align with the hypothesis that a combination of risk-independent common variants mediates resilience to LOAD by moderating genetic disease risk.
|
|
| 47. |
- Häggström, Ida, 1982-, et al.
(författare)
-
A Monte Carlo study of the dependence of early frame sampling on uncertainty and bias in pharmacokinetic parameters from dynamic PET
- 2015
-
Ingår i: Journal of Nuclear Medicine Technology. - : Society of Nuclear Medicine. - 0091-4916 .- 1535-5675. ; 43:1, s. 53-60
-
Tidskriftsartikel (refereegranskat)abstract
- Compartmental modeling of dynamic PET data enables quantifi- cation of tracer kinetics in vivo, through the calculated model parameters. In this study, we aimed to investigate the effect of early frame sampling and reconstruction method on pharmacokinetic parameters obtained from a 2-tissue model, in terms of bias and uncertainty (SD). Methods: The GATE Monte Carlo software was used to simulate 2 · 15 dynamic 3′-deoxy-3′-18F-fluorothymidine (18F-FLT) brain PET studies, typical in terms of noise level and kinetic parameters. The data were reconstructed by both 3- dimensional (3D) filtered backprojection with reprojection (3DRP) and 3D ordered-subset expectation maximization (OSEM) into 6 dynamic image sets with different early frame durations of 1, 2, 4, 6, 10, and 15 s. Bias and SD were evaluated for fitted parameter estimates, calculated from regions of interest. Results: The 2-tissue-model parameter estimates K1, k2, and fraction of arterial blood in tissue depended on early frame sampling, and a sampling of 6–15 s generally minimized bias and SD. The shortest sampling of 1 s yielded a 25% and 42% larger bias than the other schemes, for 3DRP and OSEM, respectively, and a parameter uncertainty that was 10%–70% higher. The schemes from 4 to 15 s were generally not significantly different in regards to bias and SD. Typically, the reconstruction method 3DRP yielded less framesampling dependence and less uncertain results, compared with OSEM, but was on average more biased. Conclusion: Of the 6 sampling schemes investigated in this study, an early frame duration of 6–15 s generally kept both bias and uncertainty to a minimum, for both 3DRP and OSEM reconstructions. Veryshort frames of 1 s should be avoided because they typically resulted in the largest parameter bias and uncertainty. Furthermore, 3DRP may be p
|
|
| 48. |
- Häggström, Ida, et al.
(författare)
-
Compartment Modeling of Dynamic Brain PET : The Effect of Scatter Corrections on Parameter Errors
- 2014
-
Ingår i: Medical physics (Lancaster). - : American Association of Physicists in Medicine (AAPM). - 0094-2405.
-
Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- Purpose: To investigate the effects of corrections for random and scattered coincidences on kinetic parameters in brain tumors, by using ten Monte Carlo (MC) simulated dynamic FLT-PET brain scans.Methods: The GATE MC software was used to simulate ten repetitions of a 1 hour dynamic FLT-PET scan of a voxelized head phantom. The phantom comprised six normal head tissues, plus inserted regions for blood and tumor tissue. Different time-activity-curves (TACs) for all eight tissue types were used in the simulation and were generated in Matlab using a 2-tissue model with preset parameter values (K1,k2,k3,k4,Va,Ki). The PET data was reconstructed into 28 frames by both ordered-subset expectation maximization (OSEM) and 3D filtered back-projection (3DFBP). Five image sets were reconstructed, all with normalization and different additional corrections C (A=attenuation, R=random, S=scatter): Trues (AC), trues+randoms (ARC), trues+scatters (ASC), total counts (ARSC) and total counts (AC). Corrections for randoms and scatters were based on real random and scatter sinograms that were back-projected, blurred and then forward projected and scaled to match the real counts. Weighted non-linear-least-squares fitting of TACs from the blood and tumor regions was used to obtain parameter estimates.Results: The bias was not significantly different for trues (AC), trues+randoms (ARC), trues+scatters (ASC) and total counts (ARSC) for either 3DFBP or OSEM (p<0.05). Total counts with only AC stood out however, with an up to 160% larger bias. In general, there was no difference in bias found between 3DFBP and OSEM, except in parameter Va and Ki.Conclusion: According to our results, the methodology of correcting the PET data for randoms and scatters performed well for the dynamic images where frames have much lower counts compared to static images. Generally, no bias was introduced by the corrections and their importance was emphasized since omitting them increased bias extensively.
|
|
| 49. |
- Häggström, Ida, 1982-, et al.
(författare)
-
Compartment modeling of dynamic brain PET : the impact of scatter corrections on parameter errors
- 2014
-
Ingår i: Medical physics. - : American Association of Physicists in Medicine. - 0094-2405. ; 41:11, s. 111907-
-
Tidskriftsartikel (refereegranskat)abstract
- Purpose: The aim of this study was to investigate the effect of scatter and its correction on kinetic parameters in dynamic brain positron emission tomography (PET) tumor imaging. The 2-tissue compartment model was used, and two different reconstruction methods and two scatter correction (SC) schemes were investigated.Methods: The gate Monte Carlo (MC) softwarewas used to perform 2×15 full PET scan simulations of a voxelized head phantom with inserted tumor regions. The two sets of kinetic parameters of all tissues were chosen to represent the 2-tissue compartment model for the tracer 3′-deoxy- 3′-(18F)fluorothymidine (FLT), and were denoted FLT1 and FLT2. PET data were reconstructed with both 3D filtered back-projection with reprojection (3DRP) and 3D ordered-subset expectation maximization (OSEM). Images including true coincidences with attenuation correction (AC) and true+scattered coincidences with AC and with and without one of two applied SC schemes were reconstructed. Kinetic parameters were estimated by weighted nonlinear least squares fitting of image derived time–activity curves. Calculated parameters were compared to the true input to the MC simulations.Results: The relative parameter biases for scatter-eliminated data were 15%, 16%, 4%, 30%, 9%, and 7% (FLT1) and 13%, 6%, 1%, 46%, 12%, and 8% (FLT2) for K1, k2, k3, k4,Va, and Ki, respectively. As expected, SC was essential for most parameters since omitting it increased biases by 10 percentage points on average. SC was not found necessary for the estimation of Ki and k3, however. There was no significant difference in parameter biases between the two investigated SC schemes or from parameter biases from scatter-eliminated PET data. Furthermore, neither 3DRP nor OSEM yielded the smallest parameter biases consistently although therewas a slight favor for 3DRP which produced less biased k3 and Ki estimates while OSEM resulted in a less biased Va. The uncertainty in OSEM parameterswas about 26% (FLT1) and 12% (FLT2) larger than for 3DRP although identical postfilters were applied.Conclusions: SC was important for good parameter estimations. Both investigated SC schemes performed equally well on average and properly corrected for the scattered radiation, without introducing further bias. Furthermore, 3DRP was slightly favorable over OSEM in terms of kinetic parameter biases and SDs.
|
|
| 50. |
- Häggström, Ida, 1982-, et al.
(författare)
-
Do scatter and random corrections affect the errors in kinetic parameters in dynamic PET? : a Monte Carlo study
- 2013
-
Ingår i: 2013 IEEE Nuclear Science Symposium and Medical Imaging Conference (2013 NSS/MIC). - : IEEE conference proceedings. - 9781479905348
-
Konferensbidrag (refereegranskat)abstract
- Dynamic positron emission tomography (PET) data can be evaluated by compartmental models, yielding model specific kinetic parameters. For the parameters to be of quantitative use however, understanding and estimation of errors and uncertainties associated with them are crucial.The aim in this study was to investigate the effects of the inclusion of scattered and random counts and their respective corrections on kinetic parameter errors.The MC software GATE was used to simulate two dynamic PET scans of a phantom containing three regions; blood, tissue and a static background. The two sets of time-activity-curves (TACs) used were generated for a 2-tissue compartment model with preset parameter values (K1, k2, k3, k4 and Va). The PET data was reconstructed into 19 frames by both ordered-subset expectation maximization (OSEM) and 3D filtered back-projection with reprojection (3DFBPRP) with normalization and additional corrections (A=attenuation, R=random, S=scatter, C=correction): True counts (AC), true+random counts (ARC), true+scattered counts (ASC) and total counts (ARSC).The results show that parameter estimates from true counts (AC), true+random counts (ARC), true+scattered counts (ASC) and total counts (ARSC) were not significantly different, with the exception of Va where the bias increased with added corrections. Thus, the inclusion of and correction for scattered and random counts did not affect the bias in parameter estimates K1, k2, k3, k4 and Ki. Uncorrected total counts (only AC) resulted in biases of hundreds or even thousands of percent, emphasizing the need for proper corrections. Reconstructions with 3DFBPRP resulted in overall 20-40% less biased estimates compared to OSEM.
|
|
