| 1. |
|
|
| 2. |
|
|
| 3. |
|
|
| 4. |
|
|
| 5. |
- Alsiö, Johan
(författare)
-
From Food Preference to Craving : Behavioural Traits and Molecular Mechanisms
- 2010
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Preference for palatable and energy-dense foods may be a risk factor for body weight gain and has both genetic and environmental components. Once obesity develops in an individual, weight loss is difficult to achieve. Indeed, obesity is often characterized by repeated attempts to reduce the overconsumption of energy-dense foods, followed by food craving and relapse to overconsumption. Relapse and loss of control over intake are observed also in drug addicts, and it has been shown that obesity and drug addiction not only share behavioural features but also neural circuitry, e.g. the mesolimbic dopamine pathway. In this thesis, we sought to investigate the mechanisms related to food preferences and craving using animal models previously used in addiction research. The risk of gaining weight may implicate behavioural traits and emotional states. We showed in rats that a risk-taking behavioural profile was associated both with increased preference for a high-fat (HF) diet and with increased motivational response to a palatable high-sucrose (HS) diet. Hypothalamic urocortin 2 expression was associated with the preference for the HF diet. We also tested the hypothesis that consumption of HS and HF diets separately or provided simultaneously (HFHS) affect anxiety-like behaviour and locomotion. Furthermore, we showed that withdrawal from HFHS food affects diet-induced obesity-prone (OP) and obesity-resistant (OR) animals differently. OP animals had increased motivation (craving) for HS food pellets as measured by the operant self-administration technique during withdrawal. Dopamine receptor expression in the striatum differed between OP and OR animals both at access to HFHS and during withdrawal. This strongly implicates dopaminergic signaling in the OP phenotype. In humans, food preferences may be monitored using questionnaires. We analyzed food preference data from parents of preschool children, and identified an inverse association of parental preference for high-fat high-protein food and overweight in children. In conclusion, we have employed animal models previously used in the addiction field to identify molecular mechanisms related both to food preference and vulnerability to obesity, and to food craving associated with withdrawal from palatable food. These findings add to our current understanding of obesity.
|
|
| 6. |
- Antoniou, Antonis C., et al.
(författare)
-
Common alleles at 6q25.1 and 1p11.2 are associated with breast cancer risk for BRCA1 and BRCA2 mutation carriers
- 2011
-
Ingår i: Human Molecular Genetics. - : Oxford University Press (OUP). - 0964-6906 .- 1460-2083. ; 20:16, s. 3304-3321
-
Tidskriftsartikel (refereegranskat)abstract
- Two single nucleotide polymorphisms (SNPs) at 6q25.1, near the ESR1 gene, have been implicated in the susceptibility to breast cancer for Asian (rs2046210) and European women (rs9397435). A genome-wide association study in Europeans identified two further breast cancer susceptibility variants: rs11249433 at 1p11.2 and rs999737 in RAD51L1 at 14q24.1. Although previously identified breast cancer susceptibility variants have been shown to be associated with breast cancer risk for BRCA1 and BRCA2 mutation carriers, the involvement of these SNPs to breast cancer susceptibility in mutation carriers is currently unknown. To address this, we genotyped these SNPs in BRCA1 and BRCA2 mutation carriers from 42 studies from the Consortium of Investigators of Modifiers of BRCA1/2. In the analysis of 14 123 BRCA1 and 8053 BRCA2 mutation carriers of European ancestry, the 6q25.1 SNPs (r(2) = 0.14) were independently associated with the risk of breast cancer for BRCA1 mutation carriers [ hazard ratio (HR) = 1.17, 95% confidence interval (CI): 1.11-1.23, P-trend = 4.5 x 10(-9) for rs2046210; HR = 1.28, 95% CI: 1.18-1.40, P-trend = 1.3 x 10(-8) for rs9397435], but only rs9397435 was associated with the risk for BRCA2 carriers (HR = 1.14, 95% CI: 1.01-1.28, P-trend = 0.031). SNP rs11249433 (1p11.2) was associated with the risk of breast cancer for BRCA2 mutation carriers (HR = 1.09, 95% CI: 1.02-1.17, P-trend = 0.015), but was not associated with breast cancer risk for BRCA1 mutation carriers (HR = 0.97, 95% CI: 0.92-1.02, P-trend = 0.20). SNP rs999737 (RAD51L1) was not associated with breast cancer risk for either BRCA1 or BRCA2 mutation carriers (P-trend = 0.27 and 0.30, respectively). The identification of SNPs at 6q25.1 associated with breast cancer risk for BRCA1 mutation carriers will lead to a better understanding of the biology of tumour development in these women.
|
|
| 7. |
- Asghar, Naveed, et al.
(författare)
-
Tick-borne encephalitis virus sequenced directly from questing and blood-feeding ticks reveals quasispecies variance.
- 2014
-
Ingår i: PLOS ONE. - San Francisco, USA : Public Library of Science (PLoS). - 1932-6203. ; 9:7
-
Tidskriftsartikel (refereegranskat)abstract
- The increased distribution of the tick-borne encephalitis virus (TBEV) in Scandinavia highlights the importance of characterizing novel sequences within the natural foci. In this study, two TBEV strains: the Norwegian Mandal 2009 (questing nymphs pool) and the Swedish Saringe 2009 (blood-fed nymph) were sequenced and phylogenetically characterized. Interestingly, the sequence of Mandal 2009 revealed the shorter form of the TBEV genome, similar to the highly virulent Hypr strain, within the 3' non-coding region (3'NCR). A different genomic structure was found in the 3'NCR of Saringe 2009, as in-depth analysis demonstrated TBEV variants with different lengths within the poly(A) tract. This shows that TBEV quasispecies exists in nature and indicates a putative shift in the quasispecies pool when the virus switches between invertebrate and vertebrate environments. This prompted us to further sequence and analyze the 3'NCRs of additional Scandinavian TBEV strains and control strains, Hypr and Neudoerfl. Toro 2003 and Habo 2011 contained mainly a short (A)3C(A)6 poly(A) tract. A similar pattern was observed for the human TBEV isolates 1993/783 and 1991/4944; however, one clone of 1991/4944 contained an (A)3C(A)11 poly(A) sequence, demonstrating that quasispecies with longer poly(A) could be present in human isolates. Neudoerfl has previously been reported to contain a poly(A) region, but to our surprise the re-sequenced genome contained two major quasispecies variants, both lacking the poly(A) tract. We speculate that the observed differences are important factors for the understanding of virulence, spread, and control of the TBEV.
|
|
| 8. |
- de Villiers, Sabina H. L., et al.
(författare)
-
Nicotine hapten structure, antibody selectivity and effect relationships : Results from a nicotine vaccine screening procedure
- 2010
-
Ingår i: Vaccine. - : Elsevier BV. - 0264-410X .- 1873-2518. ; 28:10, s. 2161-2168
-
Tidskriftsartikel (refereegranskat)abstract
- The aim of the present study was to synthesise and screen a set of novel nicotine hapten immunogens used for the treatment of nicotine dependence. In the screening process we studied the amount of antibodies generated and their selectivity, using ELISA techniques, and their effects on nicotine-induced dopamine release in the NAC(shell) of the rat, assessed by in vivo voltammetry. We conclude that even small changes such as the linker attachment on the nicotine molecule as well as the structure of the linker may greatly influence the selectivity of the antibodies and the central neurobiological effects of nicotine that are considered critical for its dependence producing properties. (C) 2010 Elsevier Ltd. All rights reserved.
|
|
| 9. |
- Ding, Yuan C, et al.
(författare)
-
A nonsynonymous polymorphism in IRS1 modifies risk of developing breast and ovarian cancers in BRCA1 and ovarian cancer in BRCA2 mutation carriers
- 2012
-
Ingår i: Cancer Epidemiology, Biomarkers and Prevention. - : American Association for Cancer Research. - 1055-9965 .- 1538-7755. ; 21:8, s. 1362-1370
-
Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: We previously reported significant associations between genetic variants in insulin receptor substrate 1 (IRS1) and breast cancer risk in women carrying BRCA1 mutations. The objectives of this study were to investigate whether the IRS1 variants modified ovarian cancer risk and were associated with breast cancer risk in a larger cohort of BRCA1 and BRCA2 mutation carriers.METHODS: IRS1 rs1801123, rs1330645, and rs1801278 were genotyped in samples from 36 centers in the Consortium of Investigators of Modifiers of BRCA1/2 (CIMBA). Data were analyzed by a retrospective cohort approach modeling the associations with breast and ovarian cancer risks simultaneously. Analyses were stratified by BRCA1 and BRCA2 status and mutation class in BRCA1 carriers.RESULTS: Rs1801278 (Gly972Arg) was associated with ovarian cancer risk for both BRCA1 (HR, 1.43; 95% confidence interval (CI), 1.06-1.92; P = 0.019) and BRCA2 mutation carriers (HR, 2.21; 95% CI, 1.39-3.52, P = 0.0008). For BRCA1 mutation carriers, the breast cancer risk was higher in carriers with class II mutations than class I mutations (class II HR, 1.86; 95% CI, 1.28-2.70; class I HR, 0.86; 95%CI, 0.69-1.09; P(difference), 0.0006). Rs13306465 was associated with ovarian cancer risk in BRCA1 class II mutation carriers (HR, 2.42; P = 0.03).CONCLUSION: The IRS1 Gly972Arg single-nucleotide polymorphism, which affects insulin-like growth factor and insulin signaling, modifies ovarian cancer risk in BRCA1 and BRCA2 mutation carriers and breast cancer risk in BRCA1 class II mutation carriers.Impact: These findings may prove useful for risk prediction for breast and ovarian cancers in BRCA1 and BRCA2 mutation carriers.
|
|
| 10. |
- Dunlop, Malcolm G, et al.
(författare)
-
Cumulative impact of 10 common genetic variants on colorectal cancer risk in 42,333 individuals from eight populations
- 2012
-
Ingår i: Gut. - Stockholm : Karolinska Institutet, Dept of Molecular Medicine and Surgery. - 1468-3288 .- 0017-5749.
-
Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: Colorectal cancer (CRC) has a substantial heritable component. Common genetic variation has been shown to contribute to CRC risk. A study was conducted in a large multi-population study to assess the feasibility of CRC risk prediction using common genetic variant data combined with other risk factors. A risk prediction model was built and applied to the Scottish population using available data. DESIGN: Nine populations of European descent were studied to develop and validate CRC risk prediction models. Binary logistic regression was used to assess the combined effect of age, gender, family history (FH) and genotypes at 10 susceptibility loci that individually only modestly influence CRC risk. Risk models were generated from case-control data incorporating genotypes alone (n=39 266) and in combination with gender, age and FH (n=11 324). Model discriminatory performance was assessed using 10-fold internal cross-validation and externally using 4187 independent samples. The 10-year absolute risk was estimated by modelling genotype and FH with age- and gender-specific population risks. RESULTS: The median number of risk alleles was greater in cases than controls (10 vs 9, p<2.2×10(-16)), confirmed in external validation sets (Sweden p=1.2×10(-6), Finland p=2×10(-5)). The mean per-allele increase in risk was 9% (OR 1.09; 95% CI 1.05 to 1.13). Discriminative performance was poor across the risk spectrum (area under curve for genotypes alone 0.57; area under curve for genotype/age/gender/FH 0.59). However, modelling genotype data, FH, age and gender with Scottish population data shows the practicalities of identifying a subgroup with >5% predicted 10-year absolute risk. CONCLUSION: Genotype data provide additional information that complements age, gender and FH as risk factors, but individualised genetic risk prediction is not currently feasible. Nonetheless, the modelling exercise suggests public health potential since it is possible to stratify the population into CRC risk categories, thereby informing targeted prevention and surveillance.
|
|
