Familial clustering studies indicate that breast cancer risk has a substantial genetic component. To identify new breast cancer risk variants, we genotyped approximately 300,000 SNPs in 1,600 ...Icelandic individuals with breast cancer and 11,563 controls using the Illumina Hap300 platform. We then tested selected SNPs in five replication sample sets. Overall, we studied 4,554 affected individuals and 17,577 controls. Two SNPs consistently associated with breast cancer: ∼25% of individuals of European descent are homozygous for allele A of rs13387042 on chromosome 2q35 and have an estimated 1.44-fold greater risk than noncarriers, and for allele T of rs3803662 on 16q12, about 7% are homozygous and have a 1.64-fold greater risk. Risk from both alleles was confined to estrogen receptor-positive tumors. At present, no genes have been identified in the linkage disequilibrium block containing rs13387042. rs3803662 is near the 5′ end of
TNRC9
, a high mobility group chromatin-associated protein whose expression is implicated in breast cancer metastasis to bone.
Celotno besedilo
Dostopno za:
DOBA, IJS, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
The relationship between cardiorespiratory fitness and academic achievement has been inconclusive. The results may depend on how cardiorespiratory fitness is expressed. The aim of this study is to ...explore the impact of different cardiorespiratory fitness expression methods, measured by the maximal cycle ergometer test, on the relationship between cardiorespiratory fitness and academic achievement. A cross-sectional study consisting of 303 Icelandic 4th grade students (163 girls) was conducted. Cardiorespiratory fitness was assessed using a graded maximal cycle ergometer test and scores of standardized tests in Icelandic and math obtained from the Icelandic National Examination Institute. Cardiorespiratory fitness was measured as absolute power output in watts in a maximal progressive cycle ergometer test. To adjust for different body sizes, the power output was scaled to body weight, body height, body surface area, and allometrically expressed body weight. In addition, linear regression scaling was also used to adjust for different body sizes. No significant relationship was found between any of the cardiorespiratory fitness expressions and academic achievement, using both univariate and multivariate linear regression analyses. The use of different methods to express cardiorespiratory fitness does not significantly affect the association with the academic achievement of fourth grade students.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
We carried out a genome-wide association study of breast cancer predisposition with replication and refinement studies involving 6,145 cases and 33,016 controls and identified two SNPs (rs4415084 and ...rs10941679) on 5p12 that confer risk, preferentially for estrogen receptor (ER)-positive tumors (OR = 1.27, P = 2.5 × 10−12 for rs10941679). The nearest gene, MRPS30, was previously implicated in apoptosis, ER-positive tumors and favorable prognosis. A recently reported signal in FGFR2 was also found to associate specifically with ER-positive breast cancer.
Celotno besedilo
Dostopno za:
DOBA, IJS, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
In the first half of the 20th century, Icelandic doctors and teachers began documenting the health of school children, believing that physical measurements were important to monitoring physical ...development. The measurements could also be used for comparison in other areas and for reasearch. At the Reginonal Archives of Skagafjordur, rare data about the physique of children in Saudarkrokur in 1912-1953, measured by Jon Th. Bjornsson, is preserved.
Height, weight, grip strenght, thorax expansion and tidal volume were measured twice in 2018-2019 on 7-15-year-old children in elementary schools in Saudarkrokur and Varmahlid. These measurements were compared with similar measurements from 1912-1953.
Children in 2018-2019 at ages 7-15 years were significantly taller, heavier, with greater thorax expansion and tidal volume than their peers in 1912-1953 (p<0,001-0,037). Children in 2018-2019 at ages 7-14 years had significantly higher body mass index than their peers in 1912-1953 (p<0,001-0,027). If adjusted for height and weight in thorax expansion and tidal volume measurements, similar results were found. Children in 2018-2019 had significantly less grip strength than their peers in 1912-1953 at ages 7 and 9-12-years when adjusted for height and weight (p<0,001-0,025). There was significant development in the physique of children over the years 1912-1953 in most measurements and age groups (p<0,001-0,040).
A significant increase in measured factors in 2018-2019 compared to 1912-1953 can possibly be attributed to improved quality of life.
•Accelerometer was used to measure physical activity and sedentary behavior at follow up.•Gray matter and white matter was measured both at baseline and follow up, with 5-year interval.•An ...association was found between brain atrophy and physical activity.•There was also an association between brain atrophy and sedentary behavior, independent of lifestyle physical activity.
Many studies have examined the hypothesis that greater participation in physical activity (PA) is associated with less brain atrophy. Here we examine, in a sub-sample (n=352, mean age 79.1 years) of the Age, Gene/Environment Susceptibility-Reykjavik Study cohort, the association of the baseline and 5-year change in magnetic resonance imaging (MRI)-derived volumes of gray matter (GM) and white matter (WM) to active and sedentary behavior (SB) measured at the end of the 5-year period by a hip-worn accelerometer for seven consecutive days. More GM (β=0.11; p=0.044) and WM (β=0.11; p=0.030) at baseline was associated with more total physical activity (TPA). Also, when adjusting for baseline values, the 5-year change in GM (β=0.14; p=0.0037) and WM (β=0.11; p=0.030) was associated with TPA. The 5-year change in WM was associated with SB (β=−0.11; p=0.0007). These data suggest that objectively measured PA and SB late in life are associated with current and prior cross-sectional measures of brain atrophy, and that change over time is associated with PA and SB in expected directions.
About 70% of teachers who instruct healthcare students are considered sessional (adjunct/temporary part-time) faculty and receive limited instruction in pedagogy. Sessional faculty may feel isolated ...and struggle with their teacher identity, and are often assumed to vary in their commitment, motivation, and ability to teach. However, research on teaching identity, motivations, and needs of sessional faculty is lacking. The aim of this study was to compare similarities and differences between sessional and tenure-track faculty across a health science school to guide faculty development for sessional faculty.
We developed an online needs assessment survey, based on informal interviews and literature reviews. Seventy-eight tenure-track faculty and 160 sessional faculty completed the survey (37, 25% response rate, respectively). We used validated scales to assess intrinsic motivation, identified regulated motivation, and identification with teaching, as well as developed scales (perceived connectedness, motivated by appreciation to try new teaching method) and single items. All scales demonstrated good internal consistency. We compared sessional and tenure-track faculty using t-tests/chi-square values.
We found similarities between sessional and tenure-track faculty in intrinsic motivation, identified regulated motivation, and identification with teaching. However, sessional faculty perceived less department connectedness and were more motivated to improve instruction if shown appreciation for trying new teaching methods. Sessional faculty agreed more that they desired pedagogy instruction before starting to teach and that teachers should invest energy in improving their teaching. Admitting to less participation in activities to enhance teaching in the last year, sessional faculty were more interested in digital formats of faculty development.
Our comparison suggested that sessional faculty value being a teacher as part of their self, similar to tenured faculty, but desired more appreciation for efforts to improve and perceived less connectedness to their university department than tenured faculty. They also preferred digital formats for pedagogy to improve accessibility, prior to and throughout their teaching career to support their development as teachers. Using this information as a guide, we provide suggestions for faculty development for sessional faculty. Supporting sessional faculty in the health sciences should improve the quality of teaching and positively affect student learning.
Physical activity (PA) in children has declined in recent decades, highlighting the need for effective intervention programs for school-aged children. The main objective of this study was to assess ...to what extent PA during and after school hours changed among children who received a progressive two-year long intervention vs. that of children who only received general curriculum-based PA.
A cluster randomized intervention study was conducted and six elementary schools randomly assigned to serve as control- or intervention schools. All children attending second grade (mean age = 7.4 years - born in 1999) were invited to participate in the fall of 2006 (N = 320, 82% participated), again in 2007 (midpoint) and 2008 (end of intervention). The intervention consisted of multi-component PA-intervention during school hours and was conducted by teachers at each intervention school. PA was assessed by means of accelerometers and subjectively at the intervention schools via teachers' PA log-books.
There was no difference in PA intensity (minutes of moderate-to-vigorous physical activity - min of MVPA) between the two study groups at baseline, but children in the intervention schools were more physically active at moderate-to-vigorous intensity compared to those in control schools after one year of intervention (mean difference of MVPAlog-minutes: 0.61, 95%CI: 0.02, 1.20, p = 0.04). Moreover, the model for minutes of MVPA during school hours, showed a significant three-way interaction between time at mid-point, group and gender (mean difference of MVPAlog-minutes: 1.06, 95%CI: 0.15, 1.97, p = .02), indicating a significantly greater increase among the boys in the intervention schools compared to girls. No difference in PA was detected between the study groups at the end of the study period after two years of intervention.
The results suggest that the objective of increasing PA at school was met after one year of intervention, and it was more pronounced among boys. The lack of increase at the end of the study period suggested that any increase in PA during school may highly depend on both motivation and training of general teachers. Boys may respond better to PA interventions such as the one described in this study.
In Iceland, there is a large variation in daylight between summer and winter. The aim of the study was to identify how this large variation influences physical activity (PA) and sedentary behavior ...(SB). Free living PA was measured by a waist-worn accelerometer for one week during waking hours in 138 community-dwelling older adults (61.1% women, 80.3 ± 4.9 years) during summer and winter months. In general, SB occupied about 75% of the registered wear-time and was highly correlated with age (β = 0.36). Although the differences were small, more time was spent during the summer in all PA categories, except for the moderate-to-vigorous PA (MVPA), and SB was reduced. More lifestyle PA (LSPA) was accumulated in ≥5-min bouts during summer than winter, especially among highly active participants. This information could be important for policy makers and health professionals working with older adults. Accounting for seasonal difference is necessary in analyzing SB and PA data.
Background:
There are 2 movement patterns associated with an anterior cruciate ligament (ACL) injury: dynamic valgus and stiff landing. Although sex-dependent differences have been identified for ...adults, less is known for preadolescent athletes regarding movement patterns known to load the ACL.
Hypothesis:
We hypothesized that girls would demonstrate greater vertical ground reaction forces and knee valgus angles. We further hypothesized that the exercise intervention would affect girls more than boys and that this would primarily be demonstrated in less sagittal plane excursions, increased vertical ground reaction forces and knee valgus moments for girls than for boys.
Study Design:
Controlled laboratory study.
Methods:
Male and female soccer and handball players (n = 288; age range, 9-12 years) were recruited. A motion capture system synchronized to a force platform was used to record 5 trials of a cutting maneuver before and after a 5-minute fatigue intervention. Linear mixed models were constructed, and analysis of variance was used to analyze differences in outcomes associated with the sex of the athletes.
Results:
Boys showed greater peak knee valgus moment (0.26 vs 0.22 N·m/kg, respectively; P = .048), peak knee internal rotation moment (–0.13 vs –0.10 N·m/kg, respectively; P = .021), knee rotation excursion (–7.9° vs –6.9°, respectively; P = .014), and knee extension excursion (2.7° vs 1.4°, respectively; P < .001) compared with that in girls. A significant sex × fatigue intervention interaction (F = 7.6; P = .006) was found, which was caused by a greater increase in first peak vertical ground-reaction force (vGRF) from before to after the fatigue intervention for girls (15.3 to 16.0 N/kg) compared with boys (16.4 to 16.5 N/kg).
Conclusion:
Differences detected for biomechanical factors during the cutting maneuver do not point to a greater ACL injury risk for prepubescent or early pubescent girls than for boys. Nonetheless, girls go on to develop more detrimental movement patterns in adolescence than those in boys in terms of biomechanical risk factors.
Clinical Relevance:
Early adolescence is a good target age to learn and develop muscular control; balance, strength; flexibility; and jumping, running, and landing control. This time of physical and athletic growth may therefore be an appropriate period to influence biomechanical factors and thereby task execution and the injury risk.
To identify cross-sectional and seasonal patterns of sleep and physical activity (PA) in community-dwelling, older Icelandic adults using accelerometers.
A seven-day free-living protocol of 244 (110 ...female) adults aged 79.7 ± 4.9 years was conducted as part of a larger population-based longitudinal observational-cohort study in the greater Reykjavik area of Iceland. A subpopulation (n = 72) repeated the 7-day measurement during seasonal periods with greater (13.4 ± 1.4 h) and lesser (7.7 ± 1.8 h) daylight.
Cross-sectional analyses using multiple linear regression models revealed that day length was a significant independent predictor of sleep duration, mid-sleep, and rise time (all p < 0.05). However, the actual within-individual differences in sleep patterns of the repeaters were rather subtle between periods of longer and shorter day-lengths. Compared to women, men had a shorter sleep duration (462 ± 80 vs. 487 ± 68 minutes, p = 0.008), earlier rise time, and a greater number of awakenings per night (46.5 ± 18.3 vs. 40.2 ± 15.7, p = 0.007), but sleep efficiency and onset latency were similar between the two sexes. Daily PA was also similar between men and women and between periods of longer and shorter day-lengths. BMI, age, gender, and overall PA all contributed to the variations in sleep parameters using multiple regression analysis.
The sleep and PA characteristics of this unique population revealed some gender differences, but there was limited variation in response to significant daylight changes which may be due to long-term adaptation.