-
[show abstract]
[hide abstract]
ABSTRACT: With this observation study we aimed to determine how and when sunscreen was used. 20 sun seekers were observed during a one-week sun holiday in Hurghada, Egypt. The sunscreen application thickness was related to part of body, time outdoors, exposure to ultraviolet radiation and to sunburning. Skin sites with sunscreen were exposed to UVR significantly longer and received significantly higher UVR doses than skin sites without sunscreen. They received an average of 0.62 SED [0.0-9.3 SED] (13% of their MED) before the first sunscreen application of the day. The average sunscreen used was SPF15 and the sunscreen application thickness was in average 0.79 mg cm(-)2 giving an approximated effect of SPF3. For different body parts either the total UVR exposure dose or the UVR exposure time and UVR exposure dose before the first sunscreen application were higher for sunburned than non-sunburned skin sites. In the final model gender, skin type and UVR to skin (adjusted for SPF and sunscreen application thickness) were significant predictors of sunburning. The sunscreen application thickness of 0.79 mg cm(-)2 was less than the 2 mg cm(-2) used for testing SPF. The late start of sunscreen use and improper application thickness was ineffective in preventing sunburn, and therefore could not compensate for the risk of prolonged UVR exposure and high UVR doses. Our results lead us to suspect that the protective effect of sunscreen use against DNA-damage, and thereby skin cancer, is minimal the way sunscreen is used under real sun holiday conditions.
Photochemical and Photobiological Sciences 10/2012; · 2.58 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Vitamin D studies are often performed under controlled laboratory conditions and the findings may be difficult to translate to natural conditions. We aimed to determine and compare the doses of natural solar ultraviolet radiation (UVR) with doses of artificial UVB radiation of hands and face needed to increase serum 25-hydroxyvitamin-D(3) (25(OH)D). Furthermore, we aimed to investigate the natural course of 25(OH)D due to solar exposure from April to September. 46 Caucasian volunteers were included. 17 volunteers received solar UVR (Group 1) in their natural Danish environment. Individual daily solar UVR doses in standard erythema doses (SEDs) were determined with personal wristwatch UV-dosimeters. 29 volunteers (Group 2) received artificial UVB doses of 6 SEDs (N = 14) and 3 SEDs (N = 15) on hands and face during late-winter/early-spring when outdoor UVB is negligible. 25(OH)D-levels were determined around every second week during study periods. Solar-UVR doses and sun-exposure diaries with information of sun-exposed areas were available from 8 volunteers and used for comparison with artificial UVB doses. However no significant solar-induced Δ25(OH)D was observed when sun-exposed areas were limited to hands and face. Instead the earliest period (week 17-19) with significant Δ25(OH)D, occurring after a mean of 2 days of sun-exposing more than hands and face, was used to estimate an approximate UVR dose required to increase 25(OH)D. This estimate resulted in a dose of 4.1 solar SEDs required to increase 25(OH)D by 1 nmol l(-1). The artificial dose of 6 SEDs of only hands and face significantly increased 25(OH)D and resulted in a dose of 0.52 SEDs required to increase 25(OH)D significantly by 1 nmol l(-1). Artificial UVB was thus at least 8 times more efficient in increasing 25(OH)D than solar UVR at a UV-exposed area consisting of approximately hands and face. Solar UVR exposure of larger areas may lead to enhanced efficacy but was not relevant for this comparison. Significant solar-induced Δ25(OH)D was present earliest at April 8, maximal by early August and decreased by late August.
Photochemical and Photobiological Sciences 07/2012; · 2.58 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: We have investigated the genetic involvement of the CD4 and the LAG3 genes, two appealing candidates for MS due to their suggested role in MS pathology. We genotyped a Swedish case-control material consisting of 920 MS patients and 778 controls in an initial study of CD4, three SNPs showed a significant association with MS. An independent material consisting of 1720 Nordic MS patients and 1416 controls were used for confirmation of associated markers in CD4 and to do a confirmative study of the LAG3 gene from previous findings. The result, including a total of 2640 MS patients and 2194 controls shows no significant association with CD4 and LAG3 and MS. We conclude that these genes are of minor importance in regard of genetic predisposition to the MS.
Journal of Neuroimmunology 12/2006; 180(1-2):193-8. · 2.96 Impact Factor
-
Maria Ban,
David Booth,
Robert Heard,
Graeme Stewart,
An Goris,
Koen Vandenbroeck,
Bénédicte Dubois,
Mikko Laaksonen,
Jorma Ilonen,
Mehdi Alizadeh, [......],
Anne Spurkland,
Robert Goertsches,
Pablo Villoslada,
Mefkure Eraksoy,
Anke Hensiek,
Alastair Compston,
Efrosini Setakis,
Julia Gray,
Tai Wai Yeo,
Stephen Sawcer
[show abstract]
[hide abstract]
ABSTRACT: By combining all the data available from the Genetic Analysis of Multiple sclerosis in EuropeanS (GAMES) project, we have been able to identify 17 microsatellite markers showing consistent evidence for apparent association. As might be expected five of these markers map within the Major Histocompatibility Complex (MHC) and are in LD with HLA-DRB1. Individual genotyping of the 12 non-MHC markers confirmed association for three of them--D11S1986, D19S552 and D20S894. Association mapping across the candidate genes implicated by these markers in 937 UK trio families revealed modestly associated haplotypes in JAG1 (p=0.019) on chromosome 20p12.2 and POU2AF1 (p=0.003) on chromosome 11q23.1.
Journal of Neuroimmunology 11/2006; 179(1-2):108-16. · 2.96 Impact Factor
-
Stephen Sawcer,
Maria Ban,
Mel Maranian,
Tai Wai Yeo,
Alastair Compston,
Andrew Kirby,
Mark J Daly,
Philip L De Jager,
Emily Walsh,
Eric S Lander, [......],
Mikko Laaksonen,
David Booth,
Robert Heard,
Graeme Stewart,
Robin Lincoln,
Lisa F Barcellos,
Stephen L Hauser,
Jorge R Oksenberg,
Shannon J Kenealy,
Jonathan L Haines
[show abstract]
[hide abstract]
ABSTRACT: To provide a definitive linkage map for multiple sclerosis, we have genotyped the Illumina BeadArray linkage mapping panel (version 4) in a data set of 730 multiplex families of Northern European descent. After the application of stringent quality thresholds, data from 4,506 markers in 2,692 individuals were included in the analysis. Multipoint nonparametric linkage analysis revealed highly significant linkage in the major histocompatibility complex (MHC) on chromosome 6p21 (maximum LOD score [MLS] 11.66) and suggestive linkage on chromosomes 17q23 (MLS 2.45) and 5q33 (MLS 2.18). This set of markers achieved a mean information extraction of 79.3% across the genome, with a Mendelian inconsistency rate of only 0.002%. Stratification based on carriage of the multiple sclerosis-associated DRB1*1501 allele failed to identify any other region of linkage with genomewide significance. However, ordered-subset analysis suggested that there may be an additional locus on chromosome 19p13 that acts independent of the main MHC locus. These data illustrate the substantial increase in power that can be achieved with use of the latest tools emerging from the Human Genome Project and indicate that future attempts to systematically identify susceptibility genes for multiple sclerosis will have to involve large sample sizes and an association-based methodology.
The American Journal of Human Genetics 10/2005; 77(3):454-67. · 10.60 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: We examined the proteinase inhibitor alpha2-macroglobulin (alpha2M) in plasma from patients with multiple sclerosis (MS); a neurological disease of the central nervous system. The plasma concentrations of native and transformed alpha2M were measured in 90 patients with clinically definite MS, 73 with relapsing-remitting and 17 with secondary progressive MS, and 132 healthy individuals. Significantly lower concentrations of native alpha2M and significantly higher concentrations of transformed alpha2M were found in MS patients. A significant correlation between the concentrations of native and transformed alpha2M was found. The fraction of transformed to total alpha2M in the MS patients was 36% higher than in the healthy individuals. The results suggest an important involvement of alpha2M in regulation of increased proteolytic activity occurring in MS disease.
Biochimica et Biophysica Acta 11/2004; 1690(3):203-7. · 4.66 Impact Factor
-
Annette Bang Oturai,
Lars P Ryder,
Sten Fredrikson,
Kjell-Morten Myhr,
Elisabeth G Celius,
Hanne Flinstad Harbo,
Oluf Andersen,
Eva Akesson,
Jan Hillert,
Hans O Madsen,
Harald Nyland,
Anne Spurkland, Pameli Datta,
Arne Svejgaard,
Per S Sorensen
[show abstract]
[hide abstract]
ABSTRACT: Investigation of coaffected sib pairs is one method to determine the genetic influence on the clinical presentation of many complex diseases, such as multiple sclerosis (MS). Investigation of the clinical concordance in coaffected sib pairs may be a prerequisite to identify genes that modify the clinical outcome. The aim of this study was to investigate a possible genetic influence on selected demographic and clinical variables among familial Scandinavian MS cases.
We identified 136 Caucasian Scandinavian families with MS coaffected sib pairs from Denmark, Norway and Sweden. Cohen's kappa coefficient and the intraclass correlation coefficient were used to assess concordances in sib pairs. Furthermore, clinical features and HLA-DR2 carrier status were compared among the probands of sib pairs.
We found significant concordance of the disease course (kappa = 0.28, P < 0.001) and adjusted age of onset (r = 0.23, P = 0.028). Among probands of sib pairs, HLA-DR2 carrier patients had a younger age of onset (P = 0.024).
Analyses of Scandinavian coaffected sib pairs suggest that disease course and age of onset are partly under genetic control. Furthermore, HLA-DR2 in probands of sib pairs suggests importance for age of onset.
Multiple Sclerosis 02/2004; 10(1):5-8. · 4.26 Impact Factor
-
Hanne F Harbo, Pameli Datta,
Annette Oturai,
Lars P Ryder,
Stephen Sawcer,
Efrosini Setakis,
Eva Akesson,
Elisabeth G Celius,
Helena Modin,
Magnhild Sandberg-Wollheim,
Kjell-Morten Myhr,
Oluf Andersen,
Jan Hillert,
Per Soelberg Sorensen,
Arne Svejgaard,
Alastair Compston,
Frode Vartdal,
Anne Spurkland
[show abstract]
[hide abstract]
ABSTRACT: We report the first two genome-wide screens for linkage disequilibrium between putative multiple sclerosis (MS) susceptibility genes and genetic markers performed in the genetically homogenous Scandinavian population, using 6000 microsatellite markers and DNA pools of approximately 200 MS cases and 200 controls in each screen. Usable data were achieved from the same 3331 markers in both screens. Nine markers from eight genomic regions (1p33, 3q13, 6p21, 6q14, 7p22, 9p21, 9q21 and Xq22) were identified as potentially associated with MS in both screens.
Journal of Neuroimmunology 11/2003; 143(1-2):101-6. · 2.96 Impact Factor
