Search results for "Monozygotic twin"
showing 9 items of 39 documents
Postmenopausal hormone replacement therapy modifies skeletal muscle composition and function: a study with monozygotic twin pairs
2009
We investigated whether long-term hormone replacement therapy (HRT) is associated with mobility and lower limb muscle performance and composition in postmenopausal women. Fifteen 54- to 62-yr-old monozygotic female twin pairs discordant for HRT were recruited from the Finnish Twin Cohort. Habitual (HWS) and maximal (MWS) walking speeds over 10 m, thigh muscle composition, lower body muscle power assessed as vertical jumping height, and maximal isometric hand grip and knee extension strengths were measured. Intrapair differences (IPD%) with 95% confidence intervals (CI) were calculated. The mean duration of HRT use was 6.9 ± 4.1 yr. MWS was on average 7% (0.9 to 13.1%, P = 0.019) and muscle…
Twins. Similarities, differences and individuality
2015
This study aims to investigate the self-differentiating perceptions and the separation-individuation’s process in emerging adulthood twins. A group of 40 Italian pairs of twins (21 couples dizygotic-DZ and 19 monozygotic-MZ) aged 20-30 years, were evaluated using the test of graphic projection Family Life Space (DSSVF) and thought a specific questionnaire ad hoc constructed for this research. The research hypothesis focus on Zazzo’s test of parallel testimony and provide to give empirical evidence about the capacity of MZ Twins to use more internal resources of the couple than DZ Twins, causing the split slowdown on identification. The data show that there are no difference between not bise…
Concordant Intestinal Atresia in Two Pairs of Monozygotic Twins
2011
Intestinal atresia in both twins from the same pregnancy is very rare. Only seven pairs of twins have been described. The authors report on two cases of monozygotic twins with different types of intestinal atresia and clinical evolution. Both pairs of observed twins turned out to be concordant for the presence of intestinal malformations and for the absence of other linked malformations; nevertheless, the atresic lesions were anatomically discordant in each pair of monozygotic twins. Therefore, the diagnostic and therapeutic procedures have shown some differences in phenotypic expression between the twins of both pairs. Possible etiologic factors and pathogenetic pathways are discussed, and…
Muscle function in monozygotic female twin pairs discordant for hormone replacement therapy
2011
Introduction: Postmenopausal monozygotic twin pairs discordant for hormone replacement therapy (HRT) provide an advantageous study design controlling for genetic background for elucidating the relationships between aging, sex hormone levels, muscle strength, contractile capacity, and fatigability. Methods: Thirteen postmenopausal monozygotic twin pairs discordant for HRT were measured for maximal voluntary torque (MVC) and twitch characteristics using electrical stimulation before and after intermittent dynamic plantarflexor exercise until exhaustion. Results: Peak twitch torque was 32% higher in HRT users than in their non-HRT, genetically identical sisters (P = 0.002), but MVC did not dif…
Aging and systemic hormonal status affects the circulating miR-21, miR-146a and FasL levels
2015
MicroRNAs are small molecules, found in all cell types and body fluids, which most commonly affect negatively to gene expressions by translational repression. Their role in various physiological conditions and diseases has been emphasized during the last twenty years. In our recent studies with postmenopausal monozygotic twin sisters (n=11), we have investigated how different systemic hormonal status affects the levels of specific circulating microRNAs and other molecules related to inflammation and apoptosis, both processes associated with aging. Our results have shown that the systemic levels of miR-21, miR-146a and Fas ligand are lower within the postmenopausal women who are using estrog…
Leisure-time physical activity and intra-abdominal fat in young adulthood: A monozygotic co-twin control study
2016
Objective To investigate differences in abdominal fat compartments between young adult monozygotic twin pairs discordant for leisure-time physical activity. Methods Ten young adult male monozygotic twin pairs (age range 32-36 years) discordant for leisure-time physical activity during the past 3 years were systematically selected from a population-based Finnish twin cohort. Magnetic resonance image at the level of the L2-L3 intervertebral disc was used to predict intra-abdominal and subcutaneous abdominal fat masses. Dietary intake was assessed with a 4-day food diary. Results Inactive twins had 31% more intra-abdominal fat than their active co-twins (mean difference 0.52 kg, 95% CI 0.12 to…
Combination of hormone replacement therapy and high physical activity is associated with differences in Achilles tendon size in monozygotic female tw…
2009
Estrogen concentration has been suggested to play a role in tendon abnormalities and injury. In physically active postmenopausal women, hormone replacement therapy (HRT) has been suggested to decrease tendon diameter. We hypothesized that HRT use and physical activity are associated with Achilles tendon size and tissue structure. The study applied cotwin analysis of fourteen 54- to 62-yr-old identical female twin pairs with current discordance for HRT use for an average of 7 yr. Achilles tendon thickness and cross-sectional areas were determined by ultrasonography, and tendon structural organization was analyzed from the images using linear discriminant analysis (LDA). Maximal voluntary and…
Influence of long-term postmenopausal hormone-replacement therapy on estimated structural bone strength: A study in discordant monozygotic twins
2010
Although postmenopausal hormone-replacement therapy (HRT) is known to prevent fractures, knowledge on the influence of long-term HRT on bone strength and its determinants other than areal bone mineral density is scarce. This study used a genetically controlled design with 24 monozygotic female twin pairs aged 54 to 72 years in which one cotwin was using HRT (mean duration 8 years) and the other had never used HRT. Estimated bone strength, cross-sectional area, volumetric bone mineral density, bone mineral mass, and cross-sectional density and mass distributions were assessed in the tibial shaft, distal tibia, and distal radius with peripheral computed tomography (pQCT). In the tibial shaft,…
Hormone Replacement Therapy Associated White Blood Cell DNA Methylation and Gene Expression are Associated With Within-Pair Differences of Body Adipo…
2015
The loss of estrogen during menopause causes changes in the female body, with wide-ranging effects on health. Estrogen-containing hormone replacement therapy (HRT) leads to a relief of typical menopausal symptoms, benefits bone and muscle health, and is associated with tissue-specific gene expression profiles. As gene expression is controlled by epigenetic factors (including DNA methylation), many of which are environmentally sensitive, it is plausible that at least part of the HRT-associated gene expression is due to changes in DNA methylation profile. We investigated genome-wide DNA methylation and gene expression patterns of white blood cells (WBCs) and their associations with body compo…