The effect of past use of oral contraceptive on bone mineral density, bone biochemical markers and muscle strength in healthy pre and post menopausal women

<p>Abstract</p> <p>Background</p> <p>during adulthood, most studies have reported that oral contraceptive (OC) pills had neutral, or possibly beneficial effect on bone health. We proposed this study of pre and post menopausal women assessing BMD, bone biochemical markers and physical performance among OC past users and comparable women who have never use Ocs.</p> <p>Methods</p> <p>A cross-sectional study comparing the bone density, bone biochemical markers (osteocalcin, CTX) and three measures to assess physical performance: timed get-up-and-go test "TGUG", five-times-sit-to-stand test "5 TSTS" and 8-feet speed walk "8 FSW" of users and never users OC. We were recruited 210 women who used OC for at least 2 years with that of 200 nonusers was carried out in pre and postmenopausal women (24-86 years).</p> <p>Results</p> <p>when analysing the whole population, BMD and biochemical markers values were similar for Ocs past users and control subjects. However when analysing the subgroup of premenopausal women, there was a statistically significant difference between users and never-users in osteocalcin (15,5 ± 7 ng/ml vs 21,6 ± 9 ng/ml; p = 0,003) and CTX (0,30 ± 0,1 ng/ml vs 0,41 ± 0,2 ng/ml; p = 0,025). This difference persisted after adjustment for age, BMI, age at menarche and number of pregnancies. In contrast, in post menopausal women, there was no difference in bone biochemical markers between OC users and the control. On the other hand OC past users had a significant greater performance than did the never users group. And when analysing the physical performance tests by quartile OC duration we found a significant negative association between the three tests and the use of OC more than 10 years.</p> <p>Conclusion</p> <p>the funding show no evidence of a significant difference in BMD between Ocs users and never user control groups, a decrease in bone turn over in OC pre menopausal users and a greater physical performances in patients who used OC up than 10 years.</p

Evidence of maternal QTL affecting growth and obesity in adult mice

Most quantitative trait loci (QTL) studies fail to account for the effect that the maternal genotype may have on an individual’s phenotypes, even though maternal effect QTL have been shown to account for considerable variation in growth and obesity traits in mouse models. Moreover, the fetal programming theory suggests that maternal effects influence an offspring’s adult fitness, although the genetic nature of fetal programming remains unclear. Within this context, our study focused on mapping genomic regions associated with maternal effect QTL by analyzing the phenotypes of chromosomes 2 and 7 subcongenic mice from genetically distinct dams. We analyzed 12 chromosome 2 subcongenic strains that spanned from 70 to 180 Mb with CAST/EiJ donor regions on the background of C57BL/6 J, and 14 chromosome 7 subcongenic strains that spanned from 81 to 111 Mb with BALB/cByJ donor regions on C57BL/6ByJ background. Maternal QTL analyses were performed on the basis of overlapping donor regions between subcongenic strains. We identified several highly significant (P < 5 × 10−4) maternal QTL influencing total body weight, organ weight, and fat pad weights in both sets of subcongenics. These QTL accounted for 1.9-11.7% of the phenotypic variance for growth and obesity and greatly narrowed the genomic regions associated with the maternal genetic effects. These maternal effect QTL controlled phenotypic traits in adult mice, suggesting that maternal influences at early stages of development may permanently affect offspring performance. Identification of maternal effects in our survey of two sets of subcongenic strains, representing approximately 5% of the mouse genome, supports the hypothesis that maternal effects represent significant sources of genetic variation that are largely ignored in genetic studies

Laser capture microdissection in forensic research: a review

In forensic sciences, short tandem repeat (STR) analysis has become the prime tool for DNA-based identification of the donor(s) of biological stains and/or traces. Many traces, however, contain cells and, hence, DNA, from more than a single individual, giving rise to mixed genotypes and the subsequent difficulties in interpreting the results. An even more challenging situation occurs when cells of a victim are much more abundant than the cells of the perpetrator. Therefore, the forensic community seeks to improve cell-separation methods in order to generate single-donor cell populations from a mixed trace in order to facilitate DNA typing and identification. Laser capture microdissection (LCM) offers a valuable tool for precise separation of specific cells. This review summarises all possible forensic applications of LCM, gives an overview of the staining and detection options, including automated detection and retrieval of cells of interest, and reviews the DNA extraction protocols compatible with LCM of cells from forensic samples

Comparing population health in the United States and Canada

<p>Abstract</p> <p>Background</p> <p>The objective of the paper is to compare population health in the United States (US) and Canada. Although the two countries are very similar in many ways, there are potentially important differences in the levels of social and economic inequality and the organization and financing of and access to health care in the two countries.</p> <p>Methods</p> <p>Data are from the Joint Canada/United States Survey of Health 2002/03. The Health Utilities Index Mark 3 (HUI3) was used to measure overall health-related quality of life (HRQL). Mean HUI3 scores were compared, adjusting for major determinants of health, including body mass index, smoking, education, gender, race, and income. In addition, estimates of life expectancy were compared. Finally, mean HUI3 scores by age and gender and Canadian and US life tables were used to estimate health-adjusted life expectancy (HALE).</p> <p>Results</p> <p>Life expectancy in Canada is higher than in the US. For those < 40 years, there were no differences in HRQL between the US and Canada. For the 40+ group, HRQL appears to be higher in Canada. The results comparing the white-only population in both countries were very similar. For a 19-year-old, HALE was 52.0 years in Canada and 49.3 in the US.</p> <p>Conclusions</p> <p>The population of Canada appears to be substantially healthier than the US population with respect to life expectancy, HRQL, and HALE. Factors that account for the difference may include access to health care over the full life span (universal health insurance) and lower levels of social and economic inequality, especially among the elderly.</p

H2S biosynthesis and catabolism: new insights from molecular studies

Hydrogen sulfide (H2S) has profound biological effects within living organisms and is now increasingly being considered alongside other gaseous signalling molecules, such as nitric oxide (NO) and carbon monoxide (CO). Conventional use of pharmacological and molecular approaches has spawned a rapidly growing research field that has identified H2S as playing a functional role in cell-signalling and post-translational modifications. Recently, a number of laboratories have reported the use of siRNA methodologies and genetic mouse models to mimic the loss of function of genes involved in the biosynthesis and degradation of H2S within tissues. Studies utilising these systems are revealing new insights into the biology of H2S within the cardiovascular system, inflammatory disease, and in cell signalling. In light of this work, the current review will describe recent advances in H2S research made possible by the use of molecular approaches and genetic mouse models with perturbed capacities to generate or detoxify physiological levels of H2S gas within tissue