70 research outputs found
Selenium-induced senescence involves heterochromatin formation
Abstract
We have recently shown that selenium compounds can induce a senescence response in a manner depending on ataxia-telangiectasia mutated (ATM), DNA-dependent protein kinase (DNA-PK), p53 and reactive oxygen species (ROS). To test the hypothesis that the selenium-induced senescence response involves epigenetic changes in senescence-associated heterochromatin foci (SAHF), we determined the expression of histone H3 Lysine 9 trimethylation (H3K9me3), a marker of SAHF, in human primary MRC-5 cells treated with methylseleninic acid (MSeA, 2 μM) for 2 days, followed by a 7-day recovery, in the presence or absence of KU55933 (10 μM), an ATM kinase inhibitor, and NU7026 (10 μM), a DNA-PK kinase inhibitor. Our results showed that MSeA treatment induced the formation of SAHF and H3K9me3 foci. Pre-treatment of the cells with KU55955 or NU7026 resulted in numerous and smaller foci, and they did not co-localize with the MSeA-induced SAHF. These results suggest that the MSeA-induced senescence response involves epigenetic changes of H3K9me3 in a manner depending on ATM and DNA-PK
The Role of Vaginal Smooth Muscle in the Pathogenesis of Pelvic Organ Prolapse
Pelvic organ prolapse (POP) is a life changing condition affecting over 50% of women aged 50 and older. Women with POP typically suffer from sexual, defecatory and urinary dysfunction, resulting from the decent of their unsupported pelvic organs into the vaginal canal. Over one billion dollars in annual costs are associated with surgery to repair POP. In general, surgical repair strategies merely provide an anatomical repair and fail to address the underlying cause of POP, thus increasing the risk of reoccurrence and complications. Vaginal birth injury (VaBI) has been identified as a major risk factor for POP, and as such, provides an opportunity to better understand how POP develops, in order to provide alternate remedies. To date, the exact mechanism by which vaginal delivery leads to POP remains elusive, as the time lapse between childbirth and POP symptoms (usually 20-30 years) creates multiple confounders that limit the ability to prove causality. Therefore, the goal of this thesis work was to utilize controlled animal models to assess the impact of VaBI on vaginal smooth muscle (VaSM), as a possible mechanism of VaBI in the pathogenesis of POP. In addition, we wish to examine the impact of current surgical mesh repair on VaSM functional outcomes. Specially, this work 1) investigated the impact of a simulated vaginal birth injury on VaSM 2) characterized the impact of a potential loss of smooth muscle function on vaginal biaxial mechanics, and 3) evaluated the ability of surgical mesh, designed to restore the unsupported organs to their anatomical position, on VaSM function. Our findings indicate that vaginal birth injury can cause non-recoverable loss in Vim function, and that a loss of function alters vaginal mechanics, with the potential to compromise support of the pelvic organs. Additionally, the results showed that surgically implanted meshes have mechanical and textile properties that further promote a loss of VaSM function. Ultimately, we hope that these findings motivate the need for more measures to prevent VaSM injury during delivery, and perhaps serve as a guide for the design of de novo meshes aiming to improve VaSM function
Factors affecting innovation in electric flight
Air travel growth in the United States is expected to increase by a rate of 1.8% per year over the next 20 years (FAA, 2022). This spike in air travel will dramatically increase the demand for fossil fuel making the aviation industry\u27s carbon footprint more significant. To mitigate this risk, the importance of continued work towards electric flight is clearly recognized as a suitable alternative. The first purpose of this paper is to conduct a literature review to research, comprehend, and present a clear understanding of the factors promoting and preventing innovation in electric flight. Examples of these factors include political pressures, ecological impacts, lack of technology, and safety concerns. The second purpose of this paper is to educate individuals on the current status of electric flight, and to provide recommendations on how to create a more sustainable future in aviation. Knowing what direction electric flight is moving towards while determining the sustainability, future market, and available technology could be vital to investors, large airliners, and the general aviation industry
Coverage and use of insecticide-treated bed nets in households with children aged under five years in Liberia
SOCIAL DETERMINANTS OF PRENATAL CARE USE IN SUB-SAHARAN AFRICA: EXPLORING EQUITY IN CONTENT AND OUTCOMES OF CARE
Objectives: This study examined prenatal care use among women in sub-Saharan Africa, focusing on the West African region. The primary analysis examined variations by individual and national measures of wealth and literacy. Secondary analyses examined whether adequate prenatal care is associated with lower risk of infant mortality for women in all income groups.
Methods: Analyses used data from Demographic and Health Surveys, completed between 2006 and 2010 in Benin, Burkina Faso, Ghana, Guinea, Liberia, Mali, Niger, Nigeria, Senegal and Sierra Leone, to examine prenatal care use among women with a recent live birth (58,512 respondents). Chi-square tests, multivariate logistic regression and proportional hazards regression were used to test study hypotheses. Adequate prenatal care was defined by the World Health Organization’s recommendations of at least four prenatal care visits beginning in the first trimester, with at least one visit with a skilled health professional. Individuals were grouped into wealth quintiles based on household assets. Models were adjusted for the following predisposing, enabling and need characteristics, which were available for all countries: age, parity, marital status, religion, pregnancy wantedness, rural/urban residence, occupation, and involvement in decision-making at home.
Results: In multivariate analyses, women who could not read had lower odds of adequate prenatal care compared to literate women (odds ratio, OR 0.70; 95% confidence interval, CI 0.66-0.74). Similarly, women in the poorest quintile were less likely to
receive adequate prenatal care compared to women in the wealthiest quintile (OR 0.31; CI 0.28-0.34). Each one-point increase in the literacy rate among women was associated with 4% higher odds of having adequate prenatal care (OR 1.04; CI 1.01-1.08). The effect of prenatal care on infant mortality varied significantly by wealth quintile. In the wealthiest quintile, women with adequate prenatal care had 34% lower risk of infant death compared to women with inadequate or no care (hazard ratio, HR 0.66; CI 0.51- 0.85). However, the effect of adequate prenatal care on infant death was not significant for women in other wealth quintiles.
Discussion: Findings from this study suggest that illiteracy and poverty may both increase the likelihood of inadequate prenatal care, even when use of prenatal care is high. Findings highlight effects of wealth disparities on the use of prenatal care and on infant mortality. These effects suggest that additional interventions focused on reducing poverty may be useful for improving maternal and child health in this region. Policymakers should consider mechanisms for increasing access to skilled care by addressing barriers faced by poor, less educated women
Training Health Workers to Provide Cervical Cancer Screening: Comparison of Educational Strategies in Liberia, South Africa and Grenada
E-learning in Higher Education of Nurse and Midwife Educators in Developing Countries: The Case of Liberia
This case study describes the use of e-learning in a new graduate program in nursing and midwifery education in Liberia, a developing country recovering from a decades long internal conflict and more recently an Ebola epidemic. The program was established to prepare the educator workforce with current educational concepts and practices as well as health information. Issues involved in making the hardware and internet access are addressed. Through the voices of eleven graduate students who were also nurse and midwife instructors in education facilities throughout the country, perceptions of using e-learning for course work as well as the experience of beginning to use technology in teaching pre-service students are identified. Sustainment and expansion of e-learning challenges are addressed. To further global health security and equity in access to education the Liberian government, administrators, educators and bi- or multi-national partnerships need to prioritize investments technology and e-learning in developing countries
Effect of platelet-rich plasma on polypropylene meshes implanted in the rabbit vagina: histological analysis
- …