Medial longitudinal arch mechanics before and after a prolonged run

Collapse and reformation of the medial longitudinal arch during gait is controlled passively and actively. If either tissue group fatigues over the duration of a run, the change in arch mechanics may increase risk of running injuries. However, a 3-dimensional kinematic analysis of the medial longitudinal arch after a prolonged run has not been performed. Additionally, rarely has arch collapse been quantified for walking and running in the same study. PURPOSE: To compare arch mechanics before and after a 45 minute run and to compare walking and running arch deformation. METHODS: Thirty runners performed barefoot walking and running trials before and after a 45 minute treadmill run. Reflective markers were placed on the foot and lower limb. Arch lengthening, navicular displacement, and arch height index quantified arch motion. Arch rigidity index and dynamic arch stiffness, a new measurement, quantified resistance to collapse. RESULTS: There was a significant gender y time interaction for arch rigidity index, decreasing after the run for men and increasing for women. There was no main effect for either time or gender for any other dependent variable. Walking and running, however, were significantly different for all relevant variables. Arch collapse was significantly greater for running than walking. CONCLUSION: The structures of the medial longitudinal arch of the foot may have adapted to the cyclical loading of the run by recruiting other muscles, or the arch may be resilient to change after a non-exhausting run. Greater arch deformation during running was likely a function of increased plantarflexion moment and ground reaction forces compared to walking

Images of Women in Renaissance Literature: A Selected Bibliography of Scholarship

This bibliography offers a representative selection of scholarship on the image of woman in English literature of the sixteenth and seventeenth centuries. As one would expect, a large percentage of the items listed here were published in the last five or six years, but a surprising number of significant, detailed studies of woman\u27s place in Renaissance society were written in the early decades of this century. Moreover, the 17 studies that I have listed from the 1940s and 195Os are among the most valuable of the items that appear here - both in their scholarly concern for facts and in their imaginative application of those facts to literary problems. Much remains to be done, of course, but it is both reassuring and exciting to see how many fine scholars and critics have been working with the difficult problems that these cross-disciplinary studies present

Wharton’s jelly or bone marrow mesenchymal stromal cells improve cardiac function following myocardial infarction for more than 32 weeks in a rat model: a preliminary report

The therapeutic effect of mesenchymal stromal cells (MSCs) following myocardial infarction (MI) is small. This may be due to differences in cellular sources and donor age, route of administration, in vitro cellular manipulations and the short time course of follow up in many animal studies. Here, we compared MSCs from two different sources (adult bone marrow or Wharton’s jelly from umbilical cord) for their long-term therapeutic effect following MI in a rat model to evaluate the effect of donor age. MSCs (or control infusions) were given intravenously 24-48 hr after myocardial ischemia (MI) induced by coronary artery ligation. Cardiac function was assessed by ultrasound at time points starting from before MSC infusion through 68 weeks after MI. A significant improvement in ejection fraction was seen in animals that received MSCs in time points 25 to 31 wks after treatment (p <0.01). These results support previous work that show that MSCs can cause improvement in cardiac function and extend that work by showing that the beneficial effects are durable. To investigate MSCs’ cardiac differentiation potential, Wharton’s jelly MSCs were co-cultured with fetal or adult bone-derived marrow MSCs. When Wharton’s jelly MSCs were co-cultured with fetal MSCs, and not with adult MSCs, myotube structures were observed in two-three days and spontaneous contractions (beating) cells were observed in fiveseven days. The beating structures formed a functional syncytium indicated by coordinated contractions (beating) of independent nodes. Taken together, these results suggest that MSCs given 24-48 hr after MI have a significant and durable beneficial effect more than 25 weeks after MI and that MSC treatment can home to damaged tissue and improve heart function after intravenous infusion 24-48 hrs after MI, and that WJCs may be a useful source for off-the-shelf cellular therapy for MI

Medial Longitudinal Arch Deformation during Walking and Stair Navigation While Carrying Loads

Background: Understanding the biomechanics of the medial longitudinal arch (MLA) may provide insights into injury risk and prevention, as well as function of the arch-supporting structures. Our understanding of MLA deformation is currently limited to sit-to-stand, walking, and running. Material and Methods: Three-dimensional deformation of the MLA of the right foot was characterized in 17 healthy participants during several simulated activities of daily living. MLA deformation was quantified by both changes in arch length and navicular displacement during the stance phase of three motions: walking, stair ascent, and stair descent. Three levels of load were also evaluated: no load, a front load (13.6 kg), and a backpack load (13.6 kg). Force platforms and an eight-camera motion capture system were used to collect relevant lower extremity kinetic and kinematic data. Results: Motion type had a significant (p \u3c 0.05) effect on navicular displacement and arch length elongation with navicular displacement being greatest during stair descent, while the walking and stair descent conditions showed the greatest increase in arch length. External load did not significantly affect either of these two measures (p \u3e 0.05). Conclusion: Differences in the MLA deformation variables resulting from varied dynamic activities of daily living can be greater than those during walking and should be considered. Clinical Relevance: Detailing the mechanics of the MLA may aid in further understanding injuries associated with the MLA, and the results of the current study indicate that these mechanics change based on activity

Children\u27s experiences of companion animal maltreatment in households characterized by intimate partner violence

Cruelty toward companion animals is a well-documented, coercive tactic used by abusive partners to intimidate and control their intimate partners. Experiences of co-occurring violence are common for children living in families with intimate partner violence (IPV) and surveys show that more than half are also exposed to abuse of their pets. Given children\u27s relationships with their pets, witnessing such abuse may be traumatic for them. Yet little is known about the prevalence and significance of this issue for children. The present study examines the experiences of children in families with co-occurring pet abuse and IPV. Using qualitative methods, 58 children ages 7–12 who were exposed to IPV were asked to describe their experiences of threats to and harm of their companion animals. Following the interviews, template analysis was employed to systematically develop codes and themes. Coding reliability was assessed using Randolph\u27s free-marginal multirater kappa (kfree = .90). Five themes emerged from the qualitative data, the most common being children\u27s exposure to pet abuse as a power and control tactic against their mother in the context of IPV. Other themes were animal maltreatment to discipline or punish the pet, animal cruelty by a sibling, children intervening to prevent pet abuse, and children intervening to protect the pet during a violent episode. Results indicate that children\u27s experiences of pet abuse are multifaceted, potentially traumatic, and may involve multiple family members with diverse motives

Risk Factors for Being Seronegative following SARS-CoV-2 Infection in a Large Cohort of Health Care Workers in Denmark

Most individuals seroconvert after infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), but being seronegative is observed in 1 to 9%. We aimed to investigate the risk factors associated with being seronegative following PCR-confirmed SARS-CoV-2 infection. In a prospective cohort study, we screened health care workers (HCW) in the Capital Region of Denmark for SARS-CoV-2 antibodies. We performed three rounds of screening from April to October 2020 using an enzyme-linked immunosorbent assay (ELISA) method targeting SARS-CoV-2 total antibodies. Data on all participants’ PCR for SARS-CoV-2 RNA were captured from national registries. The Kaplan-Meier method and Cox proportional hazards models were applied to investigate the probability of being seronegative and the related risk factors, respectively. Of 36,583 HCW, 866 (2.4%) had a positive PCR before or during the study period. The median (interquartile range [IQR]) age of 866 HCW was 42 (31 to 53) years, and 666 (77%) were female. After a median of 132 (range, 35 to 180) days, 21 (2.4%) of 866 were seronegative. In a multivariable model, independent risk factors for being seronegative were self-reported asymptomatic or mild infection hazard ratio (HR) of 6.6 (95% confidence interval [CI], 2.6 to 17; P < 0.001) and body mass index (BMI) of ≥30, HR 3.1 (95% CI, 1.1 to 8.8; P = 0.039). Only a few (2.4%) HCW were not seropositive. Asymptomatic or mild infection as well as a BMI above 30 were associated with being seronegative. Since the presence of antibodies against SARS-CoV-2 reduces the risk of reinfection, efforts to protect HCW with risk factors for being seronegative may be needed in future COVID-19 surges. IMPORTANCE Most individuals seroconvert after infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), but negative serology is observed in 1 to 9%. We found that asymptomatic or mild infection as well as a BMI above 30 were associated with being seronegative. Since the presence of antibodies against SARS-CoV-2 reduces the risk of reinfection, efforts to protect HCW with risk factors for being seronegative may be needed in future COVID-19 surges

New functional and structural insights from updated mutational databases for complement factor H, Factor I, membrane cofactor protein and C3

aHUS (atypical haemolytic uraemic syndrome), AMD (age-related macular degeneration) and other diseases are associated with defective AP (alternative pathway) regulation. CFH (complement factor H), CFI (complement factor I), MCP (membrane cofactor protein) and C3 exhibited the most disease-associated genetic alterations in the AP. Our interactive structural database for these was updated with a total of 324 genetic alterations. A consensus structure for the SCR (short complement regulator) domain showed that the majority (37%) of SCR mutations occurred at its hypervariable loop and its four conserved Cys residues. Mapping 113 missense mutations onto the CFH structure showed that over half occurred in the C-terminal domains SCR-15 to -20. In particular, SCR-20 with the highest total of affected residues is associated with binding to C3d and heparin-like oligosaccharides. No clustering of 49 missense mutations in CFI was seen. In MCP, SCR-3 was the most affected by 23 missense mutations. In C3, the neighbouring thioester and MG (macroglobulin) domains exhibited most of 47 missense mutations. The mutations in the regulators CFH, CFI and MCP involve loss-of-function, whereas those for C3 involve gain-of-function. This combined update emphasizes the importance of the complement AP in inflammatory disease, clarifies the functionally important regions in these proteins, and will facilitate diagnosis and therapy

Medial longitudinal arch mechanics before and after a prolonged run

Collapse and reformation of the medial longitudinal arch during gait is controlled passively and actively. If either tissue group fatigues over the duration of a run, the change in arch mechanics may increase risk of running injuries. However, a 3-dimensional kinematic analysis of the medial longitudinal arch after a prolonged run has not been performed. Additionally, rarely has arch collapse been quantified for walking and running in the same study. PURPOSE: To compare arch mechanics before and after a 45 minute run and to compare walking and running arch deformation. METHODS: Thirty runners performed barefoot walking and running trials before and after a 45 minute treadmill run. Reflective markers were placed on the foot and lower limb. Arch lengthening, navicular displacement, and arch height index quantified arch motion. Arch rigidity index and dynamic arch stiffness, a new measurement, quantified resistance to collapse. RESULTS: There was a significant gender y time interaction for arch rigidity index, decreasing after the run for men and increasing for women. There was no main effect for either time or gender for any other dependent variable. Walking and running, however, were significantly different for all relevant variables. Arch collapse was significantly greater for running than walking. CONCLUSION: The structures of the medial longitudinal arch of the foot may have adapted to the cyclical loading of the run by recruiting other muscles, or the arch may be resilient to change after a non-exhausting run. Greater arch deformation during running was likely a function of increased plantarflexion moment and ground reaction forces compared to walking.</p