Recovery Following Proximal Humerus Fracture

There is currently a glaring gap in the existing knowledge to address individuals’ experiences while recovering from a proximal humeral fracture (PHF). The main objective of this dissertation was to understand better how recovery is perceived by individuals after PHF. This overarching objective aligned well with the broad conceptualization of the issue at hand as those provided by the International Classification of Functioning, Disability and Health (ICF). Three inter-linked studies were conducted to provide a broader picture of recovery after PHF. The first study was a systematic review of prognostic factors predicting recovery after PHF in adults. This review demonstrated the complexity of recovery through a range of multi-factorial biopsychosocial factors that are inter-connected. To describe recovery after PHF as well as facilitators/barriers and preferences to exercise from individuals’ perspectives, two studies were performed: a descriptive cross-sectional survey and a semi-structured interview. A convenience sample of 59 individuals with PHF aged ≥45 participated in the survey study and completed three self-reported validated questionnaires. The most important outcomes for participants were tapped into the daily activities and social roles. Forty-seven out of 59 participants rated themselves ‘unable’ to perform recreational activities after PHF. The main facilitators and barriers to exercise belonged to the contextual (person-environment) factors. The semi-structured interview study provided an in-depth understanding of recovery as well as facilitators and barriers to exercise through interviewing 14 individuals with PHF as a subset of those who participated in the survey. Thematic analysis used to analyze participants’ narratives revealed two core concepts: self and social connectedness. The interpretation process of interviews provided a deeper understanding of the experience of recovery, what it means and why it matters to individuals themselves. The integration of quantitative and qualitative data provided insight into the perceived recovery expectations, and a number of contextual factors that are involved in the process of recovery perceptions. One key message from this work was that person-environment factors deeply influence individuals’ perceptions on recovery, and what facilitators and barriers to exercise are through their eyes

When Is Non-Invasive Prenatal Testing Reliable in Pregnancies with a Vanishing Twin? - A Systematic Review of Case Reports

Background: Fetal demise can complicate aneuploidy screening in a multi fetal pregnancy. The cell-free DNA (CF-DNA) from a non-viable conception may be discordant with the viable fetuses. The Aim of study was to review the waiting period, follow-on single fetal demise in a twin gestation before performing NIPT (Non-Invasive Prenatal Testing).Methods: In this review article we searched through online databases of CINAHL, Cochrane, Database of Abstracts of Reviews of Effects (DARE), PubMed, Medical Library, and Google Scholar for English literature between 2011 to 2020, with the following keywords: “NIPT”, “non-invasive prenatal screening testing”, “cell-free DNA”, “vanishing twin” and “co-twin demise”. We included the studies regarding the duration between the twin vanishing or reduction and NIPT false results.Results: 201 studies across the eight scientific websites were detected; 178 of which were excluded for duplication or being irrelevant. And 29 studies were fully read. 4 case series, finally, met the criteria for systematic review. The findings suggested that the NIPT screening test can be falsely-positive several weeks after vanishing twins although the live fetus is normal. Therefore, the time duration in which the placenta can release CF-DNA of the vanished twin is unknown. In addition, several weeks after reduction, the fetal CF-DNA increases and then decreases, thus CF-DNA analyzing in multifetal pregnancies with reduction can be challenging as well.Conclusion: In pregnancies with vanishing twin or reduction, evaluating NIPT results is more complex than single fetal pregnancy. According to the reviewed studies, after a fetal demise, the cytotrophoblast continues to release to the CF-DNA in the maternal circulation for a variable time, which may cause a false-positive result if the demised twin is aneuploidy

Environmental influences on reproductive health: the importance of chemical exposures

Chemical exposures during pregnancy can have a profound and life-long impact on human health. Due to the omnipresence of chemicals in our daily life, there is continuous contact with chemicals in food, water, air and consumer products. Consequently, human biomonitoring studies show that pregnant women around the globe are exposed to a variety of chemicals. In this review, we provide a summary of current data on maternal and fetal exposure as well as health consequences from these exposures. We review several chemical classes including polychlorinated biphenyls (PCBs), perfluoroalkyl substances (PFAS), polybrominated diphenyl ethers (PBDEs), phenols, phthalates, pesticides, and metals. Additionally, we discuss environmental disparities and vulnerable populations, and future research directions. We conclude by providing some recommendations for prevention of chemical exposure and its adverse reproductive health consequences

Investigation of a Simulated Annealing Cooling Schedule used to Optimize the Estimation of the Fiber Diameter Distribution in a Peripheral Nerve Trunk

In previous studies it was determined that the fiber diameter distribution in a peripheral nerve could be estimated by a simulation technique known as group delay. These results could be further improved using a combinatorial optimization algorithm called simulated annealing. This paper explores the structure and behavior of simulated annealing for the application of optimizing the group delay estimated fiber diameter distribution. Specifically, a set of parameters known as the cooling schedule is investigated to determine its effectiveness in the optimization process. Simulated annealing is a technique for finding the global minimum (or maximum) of a cost function which may have many local minima. The set of parameters which comprise the cooling schedule dictate the rate at which simulated annealing reaches its final solution. Converging too quickly can result in sub-optimal solutions while taking too long to determine a solution can result in an unnecessarily large computational effort that would be impractical in a real-world setting. The goal of this study is to minimize the computational effort of simulated annealing without sacrificing its effectiveness at minimizing the cost function. The cost function for this application is an error value computed as the difference in the maximum compound evoked potentials between an empirically-determined template distribution of fiber diameters and an optimized set of fiber diameters. The resulting information will be useful when developing the group delay estimation and subsequent simulated annealing optimization in an experimental laboratory setting

How does lead induce male infertility?

[[abstract]]An important part of male infertility of unknown etiology may be attributed to various environmental and occupational exposures to toxic substances, such as lead. The reproductive effects of lead are complex and appear to involve multiple pathways, not all of which are fully understood. It is still unclear, for example, if male reproductive issues in lead-exposed persons are mostly related to the disruption of reproductive hormones, whether the problems are due to the lead’s direct effects on the gonads, or both? This question has been difficult to answer, because lead, especially at high levels, may adversely affect many human organs. Although lead can potentially reduce male fertility by decreasing sperm count and motility, inducing abnormal morphology and affecting functional parameters; not all studies have been able to clearly demonstrate such findings. In addition, research has shown that the blood-testis barrier can protect testicular cells from direct exposure to high levels of blood lead. For these reasons and considering the wide spectrum of lead toxicity on reproductive hormones, the present review suggests that lead’s main influence on male reproduction probably occurs by altering the reproductive hormonal axis and the hormonal control on spermatogenesis, rather than by a direct toxic effect on the seminiferous tubules of the testes. As blood lead concentrations below the currently accepted worker protection standard may still adversely affect male fertility, future studies should aim to establish more concrete links between lead exposure (especially at low levels) and subsequent male infertility. Research should also pay more attention to lead’s effects on reducing male fertility rates based on not only hormonal axis alteration, but also on the changes in sperm characteristic among exposed subjects