Search

Recently, delay discounting has been argued to be conceptually consistent with the notion of temporal horizon [Bickel, W.K., Yi, R., Kowal, B.P., Gatchalian, K.M., 2008. Cigarette smokers discount past and future rewards symmetrically and more than controls: is discounting a measure of impulsivity? Drug Alcohol Depend. 96, 256-262]. Temporal horizon refers to the temporal distance over which behavioral events or objects can influence behavior. Here we examine the results on two putative measures of temporal horizon, future time perspective (FTP) and delay discounting, collected over three separate studies (n=227), to determine the influence of smoking and gender on temporal horizon. By comparing the results on these temporal horizon measures we address our population of interest: women who smoke. One of the measures of FTP indicates that smoking women have a shorter temporal horizon than their nonsmoking counterparts. Additionally, the story completion measures of FTP are positively correlated with delay discounting. In contrast, results of delay discounting measures showed no difference between smoking women and nonsmoking women, while results of delay discounting measures indicated smoking men have a shorter temporal horizon than non-smoking men. Additionally, the results of the FTP story completion measure indicated that lower third income earners had a shortened temporal horizon compared to upper third income earners. A possible explanation for these results is explored, and the implications of the modulation of temporal horizon by gender and smoking are discussed. [ABSTRACT FROM AUTHOR]

Background: Hypertension increases the risk of lymphedema in patients with comorbidities, but whether hypertension directly compromises lymph vessel (LV) function and lymph flow is unclear. We compared the contractions of mesenteric LVs ex vivo and lymph flow in vivo between normotensive and Ang II (angiotensin II)-induced hypertensive rats and explored the ionic basis of contractile patterns. Key studies were recapitulated in spontaneously hypertensive rats and control Wistar-Kyoto rats., Methods: Video microscopy continuously recorded the diameters of cannulated rat mesenteric LVs, and high-speed optical imaging estimated mesenteric lymph flow in vivo. Jess capillary Western electrophoresis evaluated expression levels of ion channel proteins., Results: Isolated LVs from Ang II-induced hypertensive rats exhibited dysrhythmic contractions, whereas LVs from both Ang II-induced hypertensive rats and spontaneously hypertensive rats exhibited reduced diastolic diameters and cross-sectional flow. Mesenteric lymph flow in vivo was 2.9-fold lower in Ang II-induced hypertensive rats compared with normotensive rats. Surprisingly, the LVs from Ang II-induced hypertensive rats expressed fewer intact L-type Ca 2+ channel pore proteins and more modulatory cleaved C-terminal fragments. However, pharmacological block of voltage-gated K + channels but not other K + channel types in control LVs established the pattern of contractile dysfunction observed in hypertension. Jess capillary Western electrophoresis analysis confirmed a loss of Shaker-type K V 1.2 channels in LVs from hypertensive rats., Conclusions: We provide initial evidence of lymphatic contractile dysfunction and compromised lymph flow in hypertensive rats, which may be caused by a loss of K V 1.2 channels in the lymphatic muscle cells.

Background: Scholarly publications are important indicators of research productivity and investigator development in Centers of Biomedical Research Excellence (COBREs). However, no information is available to describe implementation and evaluation of writing development programs within COBREs. Therefore, this paper aimed to evaluate the first year of a campus-wide COBRE-supported writing program., Methods: A convergent parallel mixed-methods design (QUAN + QUAL) was used. All writing program participants were invited to complete post-participation surveys, and a subgroup was selected using purposive sampling to complete individual semi-structured interviews. Descriptive statistics were used to characterize survey data, and qualitative content analysis was employed to analyze interview data. Self-determination theory served as the theoretical framework by which themes were developed and interpreted., Results: Professional staff, post-doctoral fellows, and faculty from all academic ranks (n = 29) participated in the writing program during its first year. Survey respondents (n = 18, response rate 62%) rated social support (89%), group accountability (89%), hearing group members' writing goals (78%), receiving group advice (67%), and setting a weekly writing schedule (56%) as beneficial program components. Participants rated program benefits such as breaking away from other responsibilities, staying on task with writing goals, and receiving social support as most beneficial. During interviews, participants (n = 14) described five major themes related to the benefits received: 1) belonging to a community of writers; 2) managing writing-related emotions; 3) improved productivity; 4) establishing helpful writing habits; and 5) improved motivation for scholarly writing., Conclusions: This first-year programmatic evaluation demonstrates the writing program's effectiveness as a campus-level development resource supported by a research center. Both survey and interview data affirmed that participants perceived autonomy, competence, and relatedness were supported through participation in the writing program. Participants placed particular emphasis on the writing program's successful development of a community of scholarly writers., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Franks et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Cage effects: some researchers worry about them, some don't, and some aren't even aware of them. When statistical analyses do not account for cage effects, there is real reason to worry. Regardless of researchers' worries or lack thereof, all researchers should be aware of how cage effects can affect the results. The "how" depends, in part, on the experimental design. Here, I (a) define cage effects; (b) illustrate a completely randomized design (CRD) often used in animal experiments; (c) explain how statistical significance is artificially inflated when cage effects are ignored and (d) give guidance on proper analyses and on how to increase statistical power in CRDs., Competing Interests: Declaration of conflicting interestsThe author declares no conflict of interest with respect to the research, authorship, and/or publication of this article.

Introduction: Tandem gait performance reportedly predicts fall risk in people with Parkinson's disease (PwPD) and help distinguish PwPD from atypical parkinsonism. In a cross-sectional study, we previously showed that tandem gait step-width widens with increasing Hoehn and Yahr (H&Y) staging scores. In this longitudinal study, we aimed to determine if progression in tandem gait deficits is dependent on disease severity in PwPD., Methods: Participants underwent an instrumented tandem gait measurement every 6 months for at least 2 years. The mean and variability of 4 tandem gait parameters were calculated at each visit: step-width, step-length, step-time, and step-velocity. The change in these parameters over time for 3 H&Y groups (stage 1, 2 and 2.5+) compared to aging controls was determined using a random coefficients regression model. The annual percent change in tandem gait parameters was correlated with initial disease features using Kendall's τ B ., Results: 66 participants were analyzed (46 PD, 20 controls). Mean step-width increased over time in an H&Y stage-dependent manner, with H&Y 2 and H&Y 2.5+ experiencing increases of 6% and 10% per year (p = 0.001 and 0.024 respectively). Annual percent-change in step-width was correlated with initial motor Unified Parkinson's Disease Rating Scale (UPDRS) scores (Kendall's τ B  = 0.229), total UPDRS scores (τ B  = 0.249), H&Y scores (τ B  = 0.266) and inversely correlated with Montreal Cognitive Assessment (MoCA) scores (τ B  = -0.209; ps ≤ 0.019)., Conclusion: Tandem gait step-width widens over time more rapidly in more severely affected PD patients. These results suggest that tandem gait should be routinely clinically evaluated and considered in the management of imbalance in PwPD., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Tuhin Virmani reports financial support was provided by National Institute of General Medical Sciences. Tuhin Virmani reports financial support was provided by Parkinson's Foundation Inc. Tuhin Virmani reports financial support was provided by University of Arkansas for Medical Sciences. Reid D. Landes reports financial support was provided by National Center for Advancing Translational Sciences. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Background: Sub-thermoneutral housing increases facultative thermogenesis in mice, which may mask the pre-clinical efficacy of anti-obesity strategies that target energy expenditure (EE). Here, we quantified the impact of protonophore treatment on whole-body energetics in mice housed at 30°C., Methods: C57BL/6J mice ( n = 48, 24M/24F) were housed at 24°C for 2 weeks; 32 (16M/16F) were then transitioned to 30°C for a further 4 weeks. Following 2 weeks acclimation at 30°C, mice ( n = 16 per group, 8M/8F) received either normal (0 mg/L; Control) or supplemented (400 mg/L; 2,4-Dinitrophenol [DNP]) drinking water. Mice were singly housed in metabolic cages to determine total EE (TEE) and its components via respiratory gas exchange. Mitochondrial respiratory function of permeabilized liver tissue was determined by high-resolution respirometry., Results: Transitioning mice from 24°C to 30°C reduced TEE and basal EE (BEE) by 16% and 41%, respectively (both P < 0.001). Compared to 30°C controls, TEE was 2.6 kcal/day greater in DNP-treated mice (95% CI: 1.6-3.6 kcal/day, P < 0.001), which was partly due to a 1.2 kcal/day higher BEE in DNP-treated mice (95% CI: 0.6-1.7 kcal/day, P < 0.001). The absolute TEE of 30°C DNP-treated mice was lower than that of mice housed at 24°C in the absence of DNP (DNP: 9.4 ± 0.7 kcal/day vs. 24°C control: 10.4 ± 1.5 kcal/day). DNP treatment reduced overall body fat of females by 2.9 percentage points versus sex-matched controls (95% CI: 1.3%-4.5%, P < 0.001), which was at least partly due to a reduction in inguinal white fat mass., Conclusion: Protonophore treatment markedly increases EE in mice housed at 30°C. The magnitude of change in TEE of mice receiving protonophore treatment at 30°C was smaller than that brought about by transitioning mice from 24°C to 30°C, emphasizing that housing temperature must be considered when assessing anti-obesity strategies that target EE in mice., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Sadler, Landes, Treas, Sikes and Porter.)

Background: Obesity-associated inflammation drives the development of insulin resistance and type 2 diabetes. We sought to identify associations of circulating regulatory T cells (Treg) with the degree of obesity (eg, body mass index Z -score [BMIz]), insulin resistance (homeostatic model of insulin resistance [HOMA-IR]), and glycemic control (HbA1c) in children and adolescents. We further sought to examine associations among bioenergetics of peripheral blood mononuclear cells (PBMCs) and CD4 T cells and BMIz, HOMA-IR, and HbA1c., Methods: A total of 65 children and adolescents between the ages 5 and 17 years were studied. HbA1c and fasting levels of plasma glucose and insulin were measured. We quantified circulating Tregs (CD3 + CD4 + CD25 + CD127 - FoxP3 + ) by flow cytometry, and measured mitochondrial respiration (oxygen consumption rate [OCR]) and glycolysis (extracellular acidification rate [ECAR]) in PBMCs and isolated CD4 T cells by Seahorse extracellular flux analysis., Results: Tregs (% CD4) are negatively associated with BMIz but positively associated with HOMA-IR. In PBMCs, OCR/ECAR (a ratio of mitochondrial respiration to glycolysis) is positively associated with BMIz but negatively associated with HbA1c., Conclusions: In children, Tregs decrease as body mass index increases; however, the metabolic stress and inflammation associated with insulin resistance may induce a compensatory increase in Tregs. The degree of obesity is also associated with a shift away from glycolysis in PBMCs but as HbA1c declines, metabolism shifts back toward glycolysis. Comprehensive metabolic assessment of the immune system is needed to better understand the implications immune cell metabolic alterations in the progression from a healthy insulin-sensitive state toward glucose intolerance in children., Trial Registration: This observational study was registered at the ClinicalTrials.gov (NCT03960333, https://clinicaltrials.gov/study/NCT03960333?term=NCT03960333&rank=1)., Competing Interests: The authors declare no conflict of interest, financial or otherwise., (Copyright © 2024 The Author(s), Published by Wolters Kluwer Health, Inc.)

Rationale: Metformin is a commonly used antidiabetes medication with suggested anti-inflammatory and antioxidative effects. Metformin use has been associated with lower risk of asthma exacerbations and hospitalizations in adults. Here, we aimed to evaluate how asthma exacerbation rates changed after adolescents and young adults were prescribed metformin, and to learn if those changes were related to metformin prescription adherence., Methods: Using secondary data of patients between 12 and 20 years old with asthma diagnosis and a metformin prescription from the Arkansas All Payers Claim Database and Arkansas School body mass index (BMI) database, we estimated the change in annualized asthma exacerbation rates after metformin prescription. We also evaluated the association of prescription adherence to the changes in those rates using univariate and multivariate regression models., Results: A total of 464 patients met inclusion criteria. Outpatient exacerbation rates decreased after metformin prescription (13.4% only before vs. 7.8% only after, p = .009), and the annualized rate decreased more after metformin prescription as adherence increased (rank r = -.165, p < .001). After adjusting for potential confounders-age, sex, BMI, and inhaled corticoid steroid use-the strength of the association was attenuated., Conclusions: Asthma exacerbation rates decreased after metformin prescription, but a larger sample of patients who have experienced exacerbations and including patients with asthma who have not been prescribed metformin is needed to better know whether these decreases are driven by metformin use., (© 2023 Wiley Periodicals LLC.)

Purpose: Over the years, animal models of local heart irradiation have provided insight into mechanisms of and treatments for radiation-induced heart disease in human populations. However, it is not completely clear which manifestations of radiation injury are most commonly seen after whole heart irradiation, and whether certain biological factors impact experimental results. Combining 9 homogeneous studies in rat models of whole heart irradiation from one laboratory, we sought to identify experimental and/or biological factors that impact heart outcomes. We evaluated the usefulness of including (1) heart rate and (2) bodyweight as covariates when analyzing biological parameters, and (3) we determined which echocardiography, histological, and immunohistochemistry parameters are most susceptible to radiation effects. Finally, (4) as an educational example, we illustrate a hypothetical sample size calculation for a study design commonly used in evaluating radiation modifiers, using the pooled estimates from the 9 rat studies only for context. The results may assist investigators in the design and analyses of pre-clinical studies of whole heart irradiation., Materials and Methods: We made use of data from 9 rat studies from our labs, 8 published elsewhere in 2008-2017, and one unpublished study. Echocardiography, histological, and immunohistochemical parameters were collected from these studies. Using mixed effects analysis of covariance models, we estimated slopes for heart rate and bodyweight and estimated the radiation effect on each of the parameters., Results: Bodyweight was related to most echocardiography parameters, and heart rate had an effect on echocardiography parameters related to the diameter of the left ventricle. For some parameters, there was evidence that heart rate and bodyweight relationships with the parameter depended on whether the rats were irradiated. Radiation effects were found in systolic measures of echocardiography parameters related to the diameter of the left ventricle, with ejection fraction and fractional shortening, with atrial wall thickness, and with histological measures of capillary density, collagen deposition, and mast cells infiltration in the heart., Conclusion: Accounting for bodyweight, as well as heart rate, in analyses of echocardiography parameters should reduce variability in estimated radiation effects. Several echocardiography and histological parameters were particularly susceptible to whole heart irradiation, showing robust effects compared to sham-irradiation. Lastly, we provide an example approach for a sample size calculation that will contribute to a rigorous study design and reproducibility in experiments studying radiation modifiers.

Objective: The objective of this study was to quantify the effects of a 4-week, supervised, high-intensity interval training (HIIT) on intrahepatic triglyceride content (IHTG, percentage), cardiorespiratory fitness (CRF), and cardiometabolic markers in adolescents with obesity., Methods: A total of 40 adolescents (age 13-18 y, BMI 36.7 ± 5.8 kg/m 2 ) at risk for metabolic dysfunction-associated steatotic liver disease (MASLD) based on obesity and elevated Fibroscan measured controlled attenuation parameter (CAP) scores were randomized to HIIT three times a week for 4 weeks (n = 34) or observation (control; n = 6). Liver magnetic resonance imaging proton-density fat-fraction (MRI-PDFF), CAP, oral glucose tolerance test, serum alanine aminotransferase, dual-energy x-ray absorptiometry, and CRF tests were performed before and after intervention. Within- and between-group differences were compared., Results: A total of 13 (38%) and 4 (66%) children had MASLD by MRI-PDFF (IHTG ≥ 5%) in the HIIT and control groups, respectively. The implemented HIIT protocol had no impact on CRF or IHTG (baseline 5.26%, Δ = -0.31 percentage points, 95% CI: -0.77 to 0.15; p = 0.179), but it decreased the 2-h glucose concentration (baseline 116 mg/dL, Δ = -11 mg/dL; 95% CI: -17.6 to -5.5; p < 0.001). When limiting the analysis to participants with MASLD (n = 17), HIIT decreased IHTG (baseline 8.81%, Δ = -1.05 percentage points, 95% CI: -2.08 to -0.01; p = 0.048). Between-group comparisons were not different., Conclusions: The implemented exercise protocol did not reduce IHTG, but it led to modest improvement in markers of cardiometabolic health., (© 2023 The Obesity Society.)

Historically, animal numbers have most often been in the hundreds for experiments designed to estimate the dose reduction factor (DRF) of a radiation countermeasure treatment compared to a control treatment. Before 2010, researchers had to rely on previous experience, both from others and their own, to determine the number of animals needed for a DRF experiment. In 2010, a formal sample size formula was developed by Kodell et al. This theoretical work showed that sample sizes for realistic, yet hypothetical, DRF experiments could be less than a hundred animals and still have sufficient power to detect clinically meaningful DRF values. However, researchers have been slow to use the formula for their DRF experiments, whether from ignorance to its existence or hesitancy to depart from "tried and true" sample sizes. Here, we adapt the sample size formula to better fit usual DRF experiments, and, importantly, we provide real experimental evidence from two independent DRF experiments that sample sizes smaller than what have typically been used can still statistically detect clinically meaningful DRF values. In addition, we update a literature review of DRF experiments which can be used to inform future DRF experiments, provide answers to questions that researchers have asked when considering sample size calculations rather than solely relying on previous experience, whether their own or others', and, in the supplementary material, provide R code implementing the formula, along with several exercises to familiarize the user with the adapted formula., (©2023 by Radiation Research Society. All rights of reproduction in any form reserved.)

Objectives: (1) To explore the characteristics of patients with opioid use disorder (OUD) maintained on either methadone or buprenorphine and (2) to determine the relative acceptability of integrating Tai Chi (TC) practice into an ongoing medication-assisted treatment for opioid use disorder (MOUD) program., Design: Survey study., Setting: The University of Arkansas for Medical Sciences Center for Addiction Services and Treatment Program., Patients: 97 patients receiving MOUD treatment., Main Outcomes: Drug use history, treatment status, physical limitation, mental health, pain, and whether participants were interested in using TC to improve health outcomes., Results: At least 30.9 percent of the sample reported moderate or higher level of limitation in performing rigorous physical activities, pain intensity, and pain interference. Between 37.1 and 61.5 percent of the sample reported various psychiatric symptoms. Methadone patients reported higher levels of physical limitations, especially in rigorous activities (p = .012), climbing several flights of stairs (p = .001), and walking more than a mile (p = .011), but similar levels of pain (ps = .664-.689) and psychiatric symptoms (ps = .262-.879) relative to buprenorphine patients. At least 40.2 percent of participants expressed moderate or higher level of interest in TC for improving health outcomes, with methadone patients more interested in participating to ease mental and sleep problems (p = .005) and improve physical fitness (p = .015) compared to buprenorphine patients., Conclusions: High prevalence of physical limitation, pain, and psychiatric comorbidities were found in OUD patients. Since patients were interested in TC to improve their health outcomes, this low-cost intervention, if proven effective, can be integrated into ongoing MOUD programs to improve health in this population.

Background: In people with Parkinson's disease (PwPD), Freezing of Gait (FOG) episodes can be levodopa responsive (OFF-FOG) or levodopa unresponsive (ONOFF-FOG). Steady-state gait abnormalities, outside of the freezing episodes themselves also exist and the response to levodopa in these different groups has not been previously documented., Objectives: To define the levodopa responsiveness in steady-state gait in OFF-FOG and ONOFF-FOG individuals., Methods: Steady-state gait was collected in both the effective levodopa OFF-state (doses withheld > 8 h) and ON-state (1 h after levodopa dosing) in 32 PwPD; 10 with OFF-FOG and 22 with ONOFF-FOG. Levodopa response was compared between the two groups in the mean and variability (CV) of 8 spatiotemporal gait parameters., Results: Both OFF-FOG and ONOFF-FOG participants showed improvement in mean stride-length and stride-velocity with levodopa. Improvement was seen in the OFF-FOG but not the ONOFF-FOG groups in mean stride-width and CV Integrated pressure with levodopa., Discussion: In this study we show that steady-state gait deficits improve with levodopa in PwPD with OFF-FOG and ONOFF-FOG, even though episodes of FOG did not resolve in the ONOFF-FOG group. Lowering levodopa in people with ONOFF-FOG, or levodopa-unresponsive freezing of gait, should be undertake with caution and objective gait titration at different levodopa doses may be beneficial. Further work is needed to elucidate the pathophysiologic mechanisms of these differences., Competing Interests: The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Dr. Virmani received salary support from the University of Arkansas for Medical Sciences (UAMS), salary from the UAMS clinician scientist program (UAMS CSP), salary from a grant from the Parkinson’s Foundation (PF-JFA-1935) and a pilot NIGMS award (GM110702). Ms. Glover and Ms. Pillai, received salary support from the UAMS CSP, PF and NIGMS pilot awards (to TV). Dr. Landes received salary support from NIH/NCATS and the PF grant. None of the authors have any financial disclosures or conflicts of interest related to the research covered in this manuscript., (© 2023 The Author(s).)

Purpose: Astronauts on missions beyond low Earth orbit will be exposed to galactic cosmic radiation, and there is concern about potential adverse cardiovascular effects. Most of the research to identify cardiovascular risk of space radiation has been performed in rodent models. To aid in the translation of research results to humans, the current study identified long-term effects of high-energy charged particle irradiation on cardiovascular function and structure in a larger non-rodent animal model., Materials and Methods: At the age of 12 months, male New Zealand white rabbits were exposed to whole-body protons (250 MeV) or oxygen ions ( 16 O, 600 MeV/n) at a dose of 0 or 0.5 Gy and were followed for 12 months after irradiation. Ultrasonography was used to measure in vivo cardiac function and blood flow parameters at 10- and 12-months post-irradiation. At 12 months after irradiation, blood cell counts and blood chemistry values were assessed, and cardiac tissue and aorta were collected for histological as well as molecular and biochemical analyses. Plasma was used for metabolomic analysis and to quantify common markers of cardiac injury., Results: A small but significant decrease in the percentage of circulating lymphocytes and an increase in neutrophil percentage was seen 12 months after 0.5 Gy protons, while 16 O exposure resulted in an increase in monocyte percentage. Markers of cardiac injury, cardiac troponin I (cTnI) and N-Terminal pro-B-type Natriuretic Peptide were modestly increased in the proton group, and cTnI was also increased after 16 O. On the other hand, metabolomics on plasma at 12 months revealed no changes. Both types of irradiation demonstrated alterations in cardiac mitochondrial morphology and an increase in left ventricular protein levels of inflammatory cell marker CD68. However, changes in cardiac function were only mild., Conclusion: Low dose charged particle irradiation caused mild long-term changes in inflammatory markers, cardiac function, and structure in the rabbit heart, in line with previous studies in mouse and rat models., Competing Interests: Declaration of Competing Interest The authors report no conflicts of interest., (Copyright © 2023 The Committee on Space Research (COSPAR). Published by Elsevier B.V. All rights reserved.)

Missions into deep space will expose astronauts to the harsh space environment, and the degenerative tissue effects of space radiation are largely unknown. To assess the risks, in this study, male BALB/c mice were exposed to 500 mGy 5-ion simulated GCR (GCRsim) at the NASA Space Radiation Laboratory. In addition, male and female CD1 mice were exposed to GCRsim and administered a diet containing Transforming Growth Factor-beta (TGF-β)RI kinase (ALK5) inhibitor IPW-5371 as a potential countermeasure. An ultrasound was performed to investigate cardiac function. Cardiac tissue was collected to determine collagen deposition, the density of the capillary network, and the expression of the immune mediator toll-like receptor 4 (TLR4) and immune cell markers CD2, CD4, and CD45. In male BALB/c mice, the only significant effects of GCRsim were an increase in the CD2 and TLR4 markers. In male CD1 mice, GCRsim caused a significant increase in total collagens and a decrease in the expression of TLR4, both of which were mitigated by the TGF-β inhibitor diet. In female CD1 mice, GCRsim caused an increase in the number of capillaries per tissue area in the ventricles, which may be explained by the decrease in the left ventricular mass. However, this increase was not mitigated by TGF-β inhibition. In both male and female CD1 mice, the combination of GCRsim and TGF-β inhibition caused changes in left ventricular immune cell markers that were not seen with GCRsim alone. These data suggest that GCRsim results in minor changes to cardiac tissue in both an inbred and outbred mouse strain. While there were few GCRsim effects to be mitigated, results from the combination of GCRsim and the TGF-β inhibitor do point to a role for TGF-β in maintaining markers of immune cells in the heart after exposure to GCR.

Purpose: Nuclear weapons testing in the northern Marshall Islands between 1946 and 1958 resulted in ionizing radiation (IR) exposure of the thousands of Marshallese. Furthermore, numerous islands were contaminated by radioactive fallout. Significant increases in cancer and metabolic syndrome incidences have been reported among Marshallese, and potential for further increases looms due to the latency of radiation-induced health effects. The purpose of this study was to investigate the genetic and epigenetic effects of exposure to IR that could be associated with radiation-induced disease among the Northwest Arkansas (NWA) Marshallese., Materials and Methods: We performed analysis of chromosomal aberrations and DNA methylation based on residential and exposure history of NWA Marshallese., Results: Analysis of chromosomal aberrations demonstrated higher incidence of genetic rearrangements in women with self-reported history of radiation exposure (95% CI: 0.10, 1.22; p =.022). Further clustering of study participants based on their residential history demonstrated that participants who spent substantial amounts of time (≥6 months) in the northern atolls (thus, in the proximity of nuclear tests) before 1980 had more chromosomal aberrations than their peers who lived only in the southern atolls (95% CI: 0.08, -0.95; p =.021), and that this difference was driven by women. A relationship between the time spent in the northern atolls and increase in chromosomal aberrations was observed: 0.31 increase in chromosomal aberrations for every 10 years spent at northern atolls (95% CI: 0.06, 0.57; p =.020). Finally, significant inverse correlations between the chromosomal aberrations and the extent of DNA methylation of four LINE-1 elements L1PA2, L1PA16, L1PREC1, and L1P4B were identified., Conclusions: The results of this study provide first evidence of the presence of stable genetic and epigenetic rearrangements in peripheral lymphocytes of NWA Marshallese and warrant further studies to analyze the role of radiation exposure in health disparities experienced by this Pacific Island nation.

Background: Freezing of gait (FOG) is a debilitating, variably expressed motor symptom in people with Parkinson's disease (PwPD) with limited treatments., Objective: To determine if the rate of progression in spatiotemporal gait parameters in people converting from a noFOG to a FOG phenotype (FOGConv) was faster than non-convertors, and determine if gait parameters can help predict this conversion., Methods: PwPD were objectively monitored longitudinally, approximately every 6 months. Non-motor assessments were performed at the initial visit. Steady-state gait in the levodopa ON-state was collected using a gait mat (Protokinetics) at each visit. The rate of progression in 8 spatiotemporal gait parameters was calculated. FOG convertors (FOGConv) were classified if they did not have FOG at initial visit and developed FOG at a subsequent visit., Results: Thirty freezers (FOG) and 30 non-freezers were monitored an average of 3.5 years, with 10 non-freezers developing FOG (FOGConv). FOGConv and FOG had faster decline in mean stride-length, swing-phase-percent, and increase in mean total-double-support percent, coefficient of variability (CV) foot-strike-length and CV swing-phase-percent than the remaining non-freezers (noFOG). On univariate modeling, progression rates of mean stride-length, stride-velocity, swing-phase-percent, total-double-support-percent and of CV swing-phase-percent had high discriminative power (AUC > 0.83) for classification of the FOGConv and noFOG groups., Conclusion: FOGConv had a faster temporal decline in objectively quantified gait than noFOG, and progression rates of spatiotemporal gait parameters were more predictive of FOG phenotype conversion than initial (static) parameters Objectively monitoring gait in disease prediction models may help define FOG prone groups for testing putative treatments.

Background: Freezing in the levodopa-medicated-state (ON-state) is a debilitating feature of Parkinson's disease without treatment options. Studies detailing the distinguishing features between people with freezing of gait that improves with levodopa and those whose freezing continues even on levodopa are lacking., Objective: To characterize the gross motor, gait, and non-motor features of this phenotype., Methods: Instrumented continuous gait was collected in the levodopa-medicated-state in 105 patients: 43 non-freezers (no-FOG), 36 with freezing only OFF-levodopa (OFF-FOG) and 26 with freezing both ON- and OFF-levodopa (ONOFF-FOG). Evaluation of motor and non-motor disease features was undertaken using validated scales. A linear mixed model with age, sex, disease duration, and motor UPDRS scores as covariates was used to determine differences in spatiotemporal gait and non-motor disease features among the groups., Results: Compared to OFF-FOG, the ONOFF-FOG group had greater disease severity (on the Unified Parkinson's disease Rating Scale) and worse cognition (on the Montreal Cognitive Assessment, Frontal Assessment Battery and Scales for Outcome in Parkinson's disease-Cognition scales) and quality of life (on the PDQ-39), but similar mood (on the Hamilton depression and anxiety scales) and sleep quality (on Epworth sleepiness scale and RBD questionnaire). For several gait features, differences between the ONOFF-OFF groups were at least as large and in the opposite direction as differences between OFF-no groups, controlling for disease severity. Variability in ONOFF-FOG was greater than in other groups. Using results from our study and others, a power analysis for a potential future study reveals sample sizes of at least 80 ONOFF and 80 OFF-FOG patients would be needed to detect clinically meaningful differences., Conclusions: Intra-patient variability in spatiotemporal gait features was much greater in ONOFF-FOG than in the other two groups. Our results suggest that multifactorial deficits may lead to ONOFF-FOG development., Competing Interests: The authors have declared that no competing interests exist.

Epigenetic mechanisms, such as DNA methylation, regulate gene expression and play a role in the development of insulin resistance. This study evaluates how the BMI z-score (BMIz) and the homeostatic model assessment of insulin resistance (HOMA-IR), alone or in combination, relate to clinical outcomes and DNA methylation patterns in prepubertal children. DNA methylation in peripheral blood mononuclear cells (PBMCs) and clinical outcomes were measured in a cohort of 41 prepubertal children. Children with higher HOMA-IR had higher blood pressure and plasma lactate levels while children with higher BMIz had higher triglycerides levels. Moreover, the DNA methylation analysis demonstrated that a 1 unit increase in the BMIz was associated with a 0.41 (95% CI: 0.29, 0.53) increase in methylation of a CpG near the PPP6R2 gene. This gene is important in the regulation of NF-kB expression. However, there was no strong evidence that the BMIz and the HOMA-IR were synergistically related to any clinical or DNA methylation outcomes. In summary, the results suggest that obesity and insulin resistance may impact metabolic health both independently in prepubertal children. In addition, obesity also has an impact on the DNA methylation of the PPP6R2 gene. This may be a novel underlying starting point for the systemic inflammation associated with obesity and insulin resistance, in this population., (© 2022. The Author(s).)

Purpose: Astronauts in space vehicles beyond low-Earth orbit will be exposed to high charge and energy (HZE) ions, and there is concern about potential adverse effects on the cardiovascular system. Thus far, most animal studies that assess cardiac effects of HZE particles have included only males. This study assessed the effects of oxygen ions ( 16 O) as a representative ion of the intravehicular radiation environment on the heart of female mice., Materials and Methods: Female C57BL/6 J mice at 6 months of age were exposed to 16 O (600 MeV/n) at 0.25-0.26 Gy/min to a total dose of 0, 0.1, or 0.25 Gy. Cardiac function and abdominal aorta blood velocity were measured with ultrasonography at 3, 5, 7, and 9 months after irradiation. At 2 weeks, 3 months, and 9 months, cardiac tissue was collected to assess collagen deposition and markers of immune cells., Results: Ultrasonography revealed increased left ventricle mass, diastolic volume and diameter but there was no change in the abdominal aorta. There was no indication of cardiac fibrosis however, a 75 kDa peptide of left ventricular collagen type III and α-smooth muscle cell actin were increased suggesting some remodeling had occurred. Left ventricular protein levels of the T-cell marker CD2 was significantly increased at all time points, while the neutrophil marker myeloperoxidase was decreased at 2 weeks and 9 months., Conclusions: These results taken together suggest 16 O ion exposure did not result in cardiac fibrosis or cardiac dysfunction in female mice. However, it does appear mild cardiac remodeling occurs in response to HZE radiation., (Copyright © 2022. Published by Elsevier B.V.)

Purpose: While there is concern about degenerative tissue effects of exposure to space radiation during deep-space missions, there are no pharmacological countermeasures against these adverse effects. γ-Tocotrienol (GT3) is a natural form of vitamin E that has anti-oxidant properties, modifies cholesterol metabolism, and has anti-inflammatory and endothelial cell protective properties. The purpose of this study was to test whether GT3 could mitigate cardiovascular effects of oxygen ion ( 16 O) irradiation in a mouse model., Materials and Methods: Male C57BL/6 J mice were exposed to whole-body 16 O (600 MeV/n) irradiation (0.26-0.33 Gy/min) at doses of 0 or 0.25 Gy at 6 months of age and were followed up to 9 months after irradiation. Animals were administered GT3 (50 mg/kg/day s.c.) or vehicle, on Monday - Friday starting on day 3 after irradiation for a total of 16 administrations. Ultrasonography was used to measure in vivo cardiac function and blood flow parameters. Cardiac tissue remodeling and inflammatory infiltration were assessed with histology and immunoblot analysis at 2 weeks, 3 and 9 months after radiation., Results: GT3 mitigated the effects of 16 O radiation on cardiac function, the expression of a collagen type III peptide, and markers of mast cells, T-cells and monocytes/macrophages in the left ventricle., Conclusions: GT3 may be a potential countermeasure against late degenerative tissue effects of high-linear energy transfer radiation in the heart., (Copyright © 2021 The Committee on Space Research (COSPAR). Published by Elsevier B.V. All rights reserved.)

Daratumumab, a CD38-targeting monoclonal antibody, has significantly improved survival rates in multiple myeloma (MM), yet patients who progress on Daratumumab have dismal clinical outcomes with an overall median of less than 10 months. While emerging novel modalities have shown promising results, the current study explores the use of high-dose chemotherapy followed by autologous stem cell transplantation (ASCT) in heavily pretreated Daratumumab-refractory MM patients. We retrospectively investigated the outcome of 69 consecutive patients who received upfront ASCT. The median progression-free survival (PFS) for the entire patient cohort was 7.2 months with a median overall survival (OS) of 19.3 months. For patients with ≥very good partial response (VGPR), median PFS and OS improved to 9 months and 34 months, respectively. Achievement of MRD negativity in ≥VGPR did not further improve the outcome. A better performance status, younger age, longer time interval from initial MM diagnosis/initial ASCT to salvage ASCT and low-risk GEP70 were all associated with improved PFS and OS after salvage ASCT. Our results suggest a role for salvage ASCT in selected heavily pretreated and Daratumumab-refractory patients.

In the event of a radiological attack or accident, it is more likely that the absorbed radiation dose will be heterogeneous, rather than uniformly distributed throughout the body. This type of uneven dose distribution is known as partial-body irradiation (PBI). Partial exposure of the vital organs, specifically the highly radiosensitive intestines, may cause death, if the injury is significant and the post-exposure recovery is considerably compromised. Here we investigated the recovery rate and extent of recovery from PBI-induced intestinal damage in large animals. Rhesus macaques (Macaca mulatta) were randomly divided into four groups: sham-irradiated (0 Gy), 8 Gy PBI, 11 Gy PBI and 14 Gy PBI. A single dose of ionizing radiation was delivered in the abdominal region using a uniform bilateral anteroposterior and posteroanterior technique. Irradiated animals were scheduled for euthanasia on days 10, 28 or 60 postirradiation, and sham-irradiated animals on day 60. Intestinal structural injuries were assessed via crypt depth, villus height, and mucosal surface length in the four different intestinal regions (duodenum, proximal jejunum, distal jejunum and ileum) using H&E staining. Higher radiation doses corresponded with more injury at 10 days post-PBI and a faster recovery rate. However, at 60 days post-PBI, damage was still evident in all regions of the intestine. The proximal and distal ends (duodenum and ileum, respectively) sustained less damage and recovered more fully than the jejunum., (©2021 by Radiation Research Society. All rights of reproduction in any form reserved.)

Background: Atrial fibrillation (AF) is a common arrhythmia. Although radiation exposure is associated with an elevated risk of cardiovascular disease, the effects of radiation on arrhythmia, especially AF, are unclear. We evaluated the relationship between radiation and AF in a cohort of atomic bomb survivors. Methods and Results: From a baseline enrollment period (1967-1969) to 2009, 7,379 Hiroshima and Nagasaki atomic bomb survivors (mean baseline age 50.6 years, 65.8% women, 72.9% from Hiroshima) without AF and who had been exposed to estimated radiation doses between 0 and 3.614 Gy were followed-up once every 2 years. AF was identified by 12-lead electrocardiograms and medical records. Treating age as the time scale, AF incidence was modeled with Cox proportional hazards models adjusting for demographics, AF risk factors, and radiation. We modeled radiation as both a continuous variable and categorized according to radiation dose (Control [<0.005 Gy] and 5 equal-sized groups based on radiation dose quintiles in the cohort). Over 4 decades of follow-up, we identified 276 AF cases in 176,687 person-years, for an incidence rate of 1.56 per 1,000 person-years. After adjusting for sex and city, neither categorized, linear, nor linear-quadratic models showed substantive evidence of radiation effects. Similar results were obtained after adjusting for AF risk factors. Conclusions: There were no clear positive associations between radiation dose and AF risk, rather null or non-significant inverse associations., Competing Interests: K.M. is a member of Circulation Reports’ Editorial Team. The remaining authors have no conflicts of interest to declare., (Copyright © 2021, THE JAPANESE CIRCULATION SOCIETY.)

Accidental exposure to ionizing radiation may lead to delayed effects of acute radiation exposure (DEARE) in many organ systems. Activated protein C (APC) is a known mitigator of the acute radiation syndrome. To examine the role of APC in DEARE, we used a transgenic mouse model with 2- to 3-fold increased plasma levels of APC (high in APC, APCHi). Male and female APCHi mice and wild-type littermates were exposed to 9.5 Gy γ-rays with their hind-legs (bone marrow) shielded from radiation to allow long-term survival. At 3 and 6 months after irradiation, cardiac function was measured with ultrasonography. At 3 months, radiation increased cardiac dimensions in APCHi males, while decreases were seen in wild-type females. At this early time point, APCHi mice of both sexes were more susceptible to radiation-induced changes in systolic function compared to wild-types. At 6 months, a decrease in systolic function was mainly seen in male mice of both genotypes. At 6 months, specimens of heart, small intestine and dorsal skin were collected for tissue analysis. Female APCHi mice showed the most severe radiation-induced deposition of cardiac collagens but were protected against a radiation-induced loss of microvascular density. Both male and female APCHi mice were protected against a radiation induced upregulation of toll-like receptor 4 in the heart, but this did not translate into a clear protection against immune cell infiltration. In the small intestine, the APCHi genotype had no effect on an increase in the number of myeloperoxidase positive cells (seen mostly in females) or an increase in the expression of T-cell marker CD2 (males). Lastly, both male and female APCHi mice were protected against radiation-induced epidermal thickening and increase in 3-nitrotyrosine positive keratinocytes. In conclusion, prolonged high levels of APC in a transgenic mouse model had little effects on indicators of DEARE in the heart, small intestine and skin, with some differential effects in male compared to female mice., Competing Interests: The authors have declared that no competing interests exist.

The present studies evaluate the in vivo prophylactic radioprotective effects of 1-bromoacetyl-3, 3-dinitroazetidine (RRx-001), a phase III anticancer agent that inhibits c-myc and downregulates CD-47, after total body irradiation (TBI), in lethally and sublethally irradiated CD2F1 male mice. A single dose of RRx-001 was administered by intraperitoneal (IP) injection 24 h prior to a lethal or sublethal radiation dose. When irradiated with 9.35 Gy, the dose lethal to 70% of untreated mice at 30 days (LD 70/30 ), only 33% of mice receiving RRx-001 (10 mg/kg) 24 h prior to total body irradiation (TBI) died by day 30, compared to 67% in vehicle-treated mice. The same pretreatment dose of RRx-001 resulted in a significant dose reduction factor of 1.07. In sublethally TBI mice, bone marrow cellularity was increased at day 14 in the RRx-001-treated mice compared to irradiated vehicle-treated animals. In addition, significantly higher numbers of lymphocytes, platelets, percent hematocrit and percent reticulocytes were observed on days 7 and/or 14 in RRx-001-treated mice. These experiments provide proof of principle that systemic administration of RRx-001 prior to TBI significantly improves overall survival and bone marrow regeneration., Competing Interests: BO and NA are employed by the company of EpicentRx. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Jurgensen, Skinner, Oronsky, Abrouk, Graff, Landes, Culp, Summers and Cary.)

Deep-space missions may alter immune cell phenotype in the primary (e.g., thymus) and secondary (e.g., spleen) lymphoid organs contributing to the progression of a variety of diseases. In deep space missions, astronauts will be exposed to chronic low doses of HZE radiation while being in microgravity. Ground-based models of long-term uninterrupted exposures to HZE radiation are not yet available. To obtain insight in the effects of concurrent exposure to microgravity and chronic irradiation (CIR), mice received a cumulative dose of chronic 0.5 Gy gamma rays over one month ± simulated microgravity (SMG). To obtain insight in a dose rate effect, additional mice were exposed to single acute irradiation (AIR) at 0.5 Gy gamma rays. We measured proportions of immune cells relative to total number of live cells in the thymus and spleen, stress level markers in plasma, and change in body weight, food consumption, and water intake. CIR affected thymic CD3+/CD335+ natural killer T (NK-T) cells, CD25+ regulatory T (Treg) cells, CD27+/CD335- natural killer (NK1) cells and CD11c+/CD11b- dendritic cells (DCs) differently in mice subjected to SMG than in mice with normal loading. No such effects of CIR on SMG as compared to normal loading were observed in cell types from the spleen. Differences between CIR and AIR groups (both under normal loading) were found in thymic Treg and DCs. Food consumption, water intake, and body weight were less after coexposure than singular or no exposure. Compared to sham, all treatment groups exhibited elevated plasma levels of the stress marker catecholamines. These data suggest that microgravity and chronic irradiation may interact with each other to alter immune cell phenotypes in an organ-specific manner and appropriate strategies are required to reduce the health risk of crewmembers., (Copyright © 2020 The Committee on Space Research (COSPAR). Published by Elsevier B.V. All rights reserved.)

High-quality nursing research is important to healthcare and is precipitated by successful participant recruitment. Young adults aged 18 to 30 years are particularly difficult to recruit due to transitions during this time, which makes it more problematic to locate these individuals and may make it more difficult for them to prioritize the need for participation. This paper includes data from two cross-sectional survey design pilot studies that aimed to enroll young adults with congenital heart disease using a variety of recruitment methods. The number of participants enrolled in these two pilot studies (7 and 22) was much lower than expected but the recruitment challenges encountered were consistent with other research studies that have recruited young adult populations. After presenting these data and a discussion of the relevant literature, we conclude with proposed strategies for research recruitment of young adults for nurse scientists who directly impact evidence-based literature and practice with research contributions.

Background: Adults with congenital heart disease (CHD) are an emerging adult heart disease subset, now outnumbering the pediatric population with CHD., Objective: We aimed to gain understanding and knowledge of what adults with CHD perceive as important for self-management and describe these needs across demographic factors, developmental characteristics, lesion severity, and quality of life., Methods: We used a descriptive mixed-methods online survey merging 4 instruments: Adult CHD Self-management Experience Questionnaire; Adult CHD Demographic Questionnaire; Adaptive Behavior Assessment System, Third Edition; and Stanford Quality of Life Visual Numeric. Participants with CHD 18 to 30 years of age with initial defect repair before 12 months of age were recruited through support from the Adult Congenital Heart Association, clinic adult CHD support groups, and newspaper advertising. Thematic analysis for short-answer questions, descriptive analysis for demographic data and the visual numeric, and intrument-specific scoring assistant software for the Adaptive Behavior Assessment System were used., Results: We received 22 responses from 13 women and 9 men. These individuals represented 15 different heart defect diagnoses, mostly of moderate or complex lesion severity. Most had postsecondary education and were employed. Four prominent themes emerged related to self-management: desire for connectivity-psychological support; a plan for the future-education about health and life expectations; coping needs-skills for mental stress; and access to care-navigation of healthcare systems., Conclusions: Future longitudinal research and replication studies with larger samples are needed. Educational materials and targeted interventions that promote self-management benefit the aging adult with CHD population.

Purpose: Studies are required to determine whether exposures to radiation encountered during manned missions in deep space may have adverse effects on the cardiovascular system. Most of the prior studies on effects of simulated space radiation on the heart and vasculature have been performed in mouse models. To provide data from a second animal species, two studies were performed to assess effects of high-energy charged particle radiation on the heart and abdominal aorta in a rat model., Materials and Methods: In study A, male Long Evans rats were exposed to whole-body protons (250 MeV, 0.5 Gy) or oxygen ions ( 16 O, 600 MeV/n, 0.5 Gy), and ultrasonography was used to measure in vivo cardiac function and blood flow parameters at 3, 5, 9 and 12 months after radiation, followed by tissue collection at 12 months. In study B, male Long Evans rats were exposed to 16 O (1 GeV/n, 0.01-0.25 Gy), and hearts collected at 6 to 7 and 12 months for histology and western-blots., Results: Both protons (250 MeV) and 16 O (600 MeV/n) caused a decrease in left ventricular posterior wall thickness at 3-5 months, but did not change echocardiographic measures of cardiac function. In Pulsed-wave Doppler assessment of the abdominal aorta, an increase was seen in mean velocity, peak velocity, and velocity time integral at 12 months after 16 O (600 MeV/n), suggesting a change in vascular function. There were no significant changes in histopathology or histological quantification of total collagens in heart or aorta. On the other hand, an increase was seen in a 75 kDa peptide of collagen type III in the left ventricle of rats exposed to protons (250 MeV) and 16 O (600 MeV/n and 1 GeV/n), suggesting that radiation caused remodeling of existing collagens in the heart. 16 O (600 MeV/n and 1 GeV/n) caused increases in left ventricular protein levels of immune cell markers CD2, CD4, CD8, and CD68., Conclusion: A single low dose of whole body protons or 16 O in male Long Evans rats did not change cardiac function or induce gross pathological changes in the heart or aorta, but induced mild changes in vascular function and remodeling of existing collagens in the heart. Altogether, studies in prior mouse models and the current work in rats indicate minor changes in cardiac function and structure after a low dose of single-ion radiation., Competing Interests: Declaration of Competing Interests. The authors report no conflicts of interest., (Copyright © 2020 The Committee on Space Research (COSPAR). Published by Elsevier Ltd. All rights reserved.)

Purpose: To examine the differences in quality performance among agencies in urban areas and those in high utilization, low population density, and all other rural areas, defined in the Bipartisan Budget Act (BBA)., Methods: We conducted a retrospective study using 2015 data: the Home Health Compare, the Home Health Agency Utilization and Payment Use, the Provider of Services, and the Area Health Resources Files, and a file with rural categories in BBA. The quality measures included (1) hospitalizations, (2) emergency visits, (3) patient experience, (4) composite scores for improvement in activities of daily living (ADL), (5) improvement in pain and treating symptoms, (6) preventing harm, and (7) treating wounds and preventing pressure sores. We applied weighted least squares regression., Findings: Among all quality measures, differences in emergency visits of the 3 rural categories from urban agencies were the largest. The adjusted mean emergency visit for urban agencies was 12.42%, with agencies in rural areas having 1.01-1.96 percentage points higher rates than urban agencies (95% CI: 0.72-1.29 for high utilization areas, 95% CI: 0.51-3.42 for low population areas, and 95% CI: 1.28-1.78 for all other areas)., Conclusions: The differences in the quality of care among agencies in 3 categories of rural areas were small, except for emergency visits. Given policies to reduce rural add-on payments for home health services, continued monitoring of the services provided and the quality of care by home health agencies in rural areas is recommended., (© 2020 National Rural Health Association.)

N-of-1 trials allow inference between two treatments given to a single individual. Most often, clinical investigators analyze an individual's N-of-1 trial data with usual t-tests or simple nonparametric methods. These simple methods do not account for serial correlation in repeated observations coming from the individual. Existing methods accounting for serial correlation require simulation, multiple N-of-1 trials, or both. Here, we develop t-tests that account for serial correlation in a single individual. The development includes effect size and precision calculations, both of which are useful for study planning. We then use Monte Carlo simulation to evaluate statistical properties of these serial t-tests, namely, Type I and II errors, and confidence interval widths, and compare these statistical properties to those of analogous usual t-test. The serial t-tests clearly outperform the usual t-tests commonly used in reporting N-of-1 results. Examples from N-of-1 clinical trials in fibromyalgia patients and from a behavioral health setting exhibit how accounting for serial correlation can change inferences. These t-tests are easily implemented and more appropriate than simple methods commonly used; however, caution is needed when analyzing only a few observations., Competing Interests: The authors have declared that no competing interests exist.

Cardiovascular disease constitutes an important threat to humans after space missions beyond the Earth's magnetosphere. Epigenetic alterations have an important role in the etiology and pathogenesis of cardiovascular disease. Previous research in animal models has shown that protons and 56 Fe ions cause long-term changes in DNA methylation and expression of repetitive elements in the heart. However, astronauts will be exposed to a variety of ions, including the smaller fragmented products of heavy ions after they interact with the walls of the space craft. Here, we investigated the effects of 16 O on the cardiac methylome and one-carbon metabolism in male C57BL/6 J mice. Left ventricles were examined 14 and 90 days after exposure to space-relevant doses of 0.1, 0.25, or 1 Gy of 16 O (600 MeV/n). At 14 days, the two higher radiation doses elicited global DNA hypomethylation in the 5'-UTR of Long Interspersed Nuclear Elements 1 (LINE-1) compared to unirradiated, sham-treated mice, whereas specific LINE-1 elements exhibited hypermethylation at day 90. The pericentromeric major satellites were affected both at the DNA methylation and expression levels at the lowest radiation dose. DNA methylation was elevated, particularly after 90 days, while expression showed first a decrease followed by an increase in transcript abundance. Metabolomics analysis revealed that metabolites involved in homocysteine remethylation, central to DNA methylation, were unaffected by radiation, but the transsulfuration pathway was impacted after 90 days, with a large increase in cystathione levels at the lowest dose. In summary, we observed dynamic changes in the cardiac epigenome and metabolome three months after exposure to a single low dose of oxygen ions., (Copyright © 2019 The Committee on Space Research (COSPAR). Published by Elsevier Ltd. All rights reserved.)

There have been some concerns about the influence of medical X rays in dose-response analysis of atomic bomb radiation on health outcomes. Among atomic bomb survivors in the Life Span Study, the association between atomic bomb radiation dose and exposures to medical X rays was investigated using questionnaire data collected by a mail survey conducted between 2007-2011, soliciting information on the history of computed tomography (CT) scans, gastrointestinal fluoroscopy, angiography and radiotherapy. Among 12,670 participants, 76% received at least one CT scan; 77%, a fluoroscopic examination; 23%, an angiographic examination; and 8%, radiotherapy. Descriptive and multivariable-adjusted analyses showed that medical X rays were administered in greater frequencies among those who were exposed to an atomic bomb radiation dose of 1.0 Gy or higher, compared to those exposed to lower doses. This is possibly explained by a greater frequency in major chronic diseases such as cancer in the ≥1.0 Gy group. The frequency of medical X rays in the groups exposed to 0.005-0.1 Gy or 0.1-1.0 Gy did not differ significantly from those exposed to <0.005 Gy. An analysis of finer dose groups under 1 Gy likewise showed no differences in frequencies of medical X rays. Thus, no evidence of material confounding of atomic bomb effects was found. Among those exposed to atomic bomb doses <1 Gy, doses were not associated with medical radiation exposures. The significant association of doses ≥1 Gy with medical radiation exposures likely produces no substantive bias in radiation effect estimates because diagnostic medical X-ray doses are much lower than the atomic bomb doses. Further information on actual medical X-ray doses and on the validity of self-reports of X-ray procedures would strengthen this conclusion.

Objectives: In an aged Japanese population, we investigated associations of demographic variables with subjective neurocognitive complaints using the Neurocognitive Questionnaire (NCQ)., Methods: Participants ( N = 649) provided answers to the NCQ in both 2011 and 2013. Using fully-completed NCQs from 503 participants in 2011, we identified latent factors of subjective neurocognitive complaints using exploratory factor analysis; then examined associations of demographic variables with the identified factors for all 649 participants over the two years. We also examined changes in factor scores over the 2-year period., Results: We identified four factors representing 20 of the 25 NCQ items and labelled them metacognition, emotional regulation, motivation/organization, and processing speed. In a regression model using all participants, we observed linear deterioration with age on emotional regulation and linear-quadratic deterioration with age on the other factors. Less education was associated with more problems for all factors, but we detected no evidence of interaction between age and education. In 314 participants completing both assessments, paired t -tests comparing the 2013 to 2011 responses corroborated the regression results, except for emotional regulation., Conclusions: On the NCQ, older age and less education were associated with more subjective neurocognitive complaints. This is compatible with the association of the same factors with objective cognition and suggests that subjective cognitive complaints complement objective cognition as a prodrome of non-normative cognitive decline.

Purpose: Astronauts traveling beyond low-Earth orbit will be exposed to high linear-energy transfer charged particles. Because there is concern about the adverse effects of space radiation on the cardiovascular system, this study assessed cardiac function and structure and immune cell infiltration in a mouse model of charged-particle irradiation., Materials and Methods: Male C57BL/6 J mice were exposed to oxygen ions ( 16 O, 600 MeV/n at 0.25-0.26 Gy/min to a total dose of 0, 0.05, 0.1, 0.25, or 1 Gy), protons (150 MeV, 0.35-0.55 Gy/min to 0, 0.5, or 1 Gy), or protons (150 MeV, 0.5 Gy) followed by 16 O (600 MeV/n, 0.1 Gy). Separate groups of mice received 137 Cs γ-rays (1 Gy/min to 0, 0.5, 1, or 3 Gy) as a reference. Cardiac function and blood velocity were measured with ultrasonography at 3, 5, 7, and 9 months after irradiation. At 2 weeks, 3 months, and 9 months, cardiac tissue was collected to assess apoptosis, tissue remodeling, and markers of immune cells., Results: Ejection fraction and fractional shortening decreased at 3 and 7 months after 16 O. These parameters did not change in mice exposed to γ-rays, protons, or protons followed by 16 O. Each of the radiation exposures caused only small increases in cleaved caspase-3 and numbers of apoptotic nuclei. Changes in the levels of α-smooth muscle cell actin and a 75-kDa peptide of collagen type III in the left ventricle suggested tissue remodeling, but there was no significant change in total collagen deposition at 2 weeks, 3 months, and 9 months. Increases in protein amounts of cluster of differentiation (CD)2, CD68, and CD45 as measured with immunoblots at 2 weeks, 3 months, and 9 months after exposure to protons or 16 O alone suggested immune cell infiltration. For type III collagen, CD2 and CD68, the efficacy in inducing protein abundance of CD2, CD68, and CD45 was 16 O > protons > γ-rays > protons followed by 16 O., Conclusions: Low-dose, high-energy charged-particle irradiation caused mild changes in cardiac function and tissue remodeling in the mouse., (Copyright © 2019 The Committee on Space Research (COSPAR). Published by Elsevier Ltd. All rights reserved.)

The relative potency of one agent to another is commonly represented by the ratio of two quantal response parameters; for example, the LD 50 of animals receiving a treatment to the LD 50 of control animals, where LD 50 is the dose of toxin that is lethal to 50% of animals. Though others have considered interval estimators of LD 50 , here, we extend Bayesian, bootstrap, likelihood ratio, Fieller's and Wald's methods to estimate intervals for relative potency in a parallel-line assay context. In addition to comparing their coverage probabilities, we also consider their power in two types of dose designs: one assigning treatment and control the same doses vs. one choosing doses for treatment and control to achieve same lethality targets. We explore these methods in realistic contexts of relative potency of radiation countermeasures. For larger experiments (e.g., ≥100 animals), the methods return similar results regardless of the interval estimation method or experiment design. For smaller experiments (e.g., < 60 animals), Wald's method stands out among the others, producing intervals that hold closely to nominal levels and providing more power than the other methods in statistically efficient designs. Using this simple statistical method within a statistically efficient design, researchers can reduce animal numbers.

Objective: Area of muscle, fat, and bone is often measured in thigh CT scans when tissue composition is a key outcome. SliceOmatic software is commonly referenced for such analysis but published methods may be insufficient for new users. Thus, a quick start guide to calculating thigh composition using SliceOmatic has been developed., Methods: CT images of the thigh were collected from older (69 ± 4 yrs, N = 24) adults before and after 12-weeks of resistance training. SliceOmatic was used to segment images into seven density regions encompassing fat, muscle, and bone from -190 to +2000 Hounsfield Units [HU]. The relative contributions to thigh area and the effects of tissue density overlap for skin and marrow with muscle and fat were determined., Results: The largest contributors to the thigh were normal fat (-190 to -30 HU, 29.1 ± 7.4%) and muscle (35 to 100 HU, 48.9 ± 8.2%) while the smallest were high density (101 to 150 HU, 0.79 ± 0.50%) and very high density muscle (151 to 200 HU, 0.07 ± 0.02%). Training significantly (P<0.05) increased area for muscle in the very low (-29 to -1 HU, 5.5 ± 7.9%), low (0 to 34 HU, 9.6 ± 16.8%), normal (35 to 100 HU, 4.2 ± 7.9%), and high (100 to 150 HU, 70.9 ± 80.6%) density ranges for muscle. Normal fat, very high density muscle and bone did not change (P>0.05). Contributions to area were altered by ~1% or less and the results of training were not affected by accounting for skin and marrow., Conclusions: When using SliceOmatic to calculate thigh composition, accounting for skin and marrow may not be necessary. We recommend defining muscle as -29 to +200 HU but that smaller ranges (e.g. low density muscle, 0 to 34 HU) can easily be examined for relationships with the health condition and intervention of interest., Trial Registration: Clinicaltrials.gov NCT02261961., Competing Interests: The authors have declared that no competing interests exist.

Exercise is one of the most important health behaviors to reduce and prevent the severity of many chronic diseases. The purpose of the current study was to determine if adding temporal discounting (TD) would affect the predictability of the Theory of Planned Behavior (TPB) in exercising among older adults. One hundred thirty-seven older adults were recruited from 11 churches in rural Arkansas using a cross-sectional design. Information regarding participants' exercise behavior, constructs of the TPB, TD rates, and demographics was collected. Path analysis was used to examine the relationships between and among each of the concepts of the TPB and TD. TD was not a significant predictor (p = 0.413) for exercise behavior after adjusting for intention. Adding TD to the existing TPB did not significantly affect the predictability of the model negatively or positively. [Res Gerontol Nurs. 2017; 10(6):252-259.]., (Copyright 2017, SLACK Incorporated.)

Background: Methionine, a central molecule in one-carbon metabolism, is an essential amino acid required for normal growth and development. Despite its importance to biological systems, methionine is toxic when administered at supra-physiological levels. The aim of this study was to investigate the effects of short-term methionine dietary modulation on the proximal jejunum, the section of the gut specifically responsible for amino acid absorption, in a mouse model. Eight-week-old CBA/J male mice were fed methionine-adequate (MAD; 6.5 g/kg) or methionine-supplemented (MSD; 19.5 g/kg) diets for 3.5 or 6 days (average food intake 100 g/kg body weight). The study design was developed in order to address the short-term effects of the methionine supplementation that corresponds to methionine dietary intake in Western populations. Biochemical indices in the blood as well as metabolic, epigenetic, transcriptomic, metagenomic, and histomorphological parameters in the gut were evaluated., Results: By day 6, feeding mice with MSD (protein intake <10% different from MAD) resulted in increased plasma (2.3-fold; p  < 0.054), but decreased proximal jejunum methionine concentrations (2.2-fold; p  < 0.05) independently of the expression of neutral amino acid transporters. MSD has also caused small bowel bacteria colonization, increased the abundance of pathogenic bacterial species Burkholderiales and decreased the gene expression of the intestinal transmembrane proteins- Cldn8 (0.18-fold, p  < 0.05), Cldn9 (0.24-fold, p  < 0.01) and Cldn10 (0.05-fold, p  < 0.05). Feeding MSD led to substantial histomorphological alterations in the proximal jejunum exhibited as a trend towards decreased plasma citrulline concentrations (1.8-fold, p  < 0.07), as well as loss of crypt depth (by 28%, p  < 0.05) and mucosal surface (by 20%, p  < 0.001)., Conclusions: Together, these changes indicate that short-term feeding of MSD substantially alters the normal gut physiology. These effects may contribute to the pathogenesis of intestinal inflammatory diseases and/or sensitize the gut to exposure to other stressors.

Long Interspersed Nuclear Element 1 (LINE-1) retrotransposons are the major repetitive elements in mammalian genomes. LINE-1s are well-accepted as driving forces of evolution and critical regulators of the expression of genetic information. Alterations in LINE-1 DNA methylation may lead to its aberrant activity and are reported in virtually all human cancers and in experimental carcinogenesis. In this study, we investigated the endogenous DNA methylation status of the 5' untranslated region (UTR) of LINE-1 elements in the bone marrow hematopoietic stem cells (HSCs), hematopoietic progenitor cells (HPCs), and mononuclear cells (MNCs) in radioresistant C57BL/6J and radiosensitive CBA/J mice and in response to ionizing radiation (IR). We demonstrated that basal levels of DNA methylation within the 5'-UTRs of LINE-1 elements did not differ significantly between the two mouse strains and were negatively correlated with the evolutionary age of LINE-1 elements. Meanwhile, the expression of LINE-1 elements was higher in CBA/J mice. At two months after irradiation to 0.1 or 1 Gy of 137 Cs (dose rate 1.21 Gy/min), significant decreases in LINE-1 DNA methylation in HSCs were observed in prone to radiation-induced carcinogenesis CBA/J, but not C57BL/6J mice. At the same time, no residual DNA damage, increased ROS, or changes in the cell cycle were detected in HSCs of CBA/J mice. These results suggest that epigenetic alterations may potentially serve as driving forces of radiation-induced carcinogenesis; however, future studies are needed to demonstrate the direct link between the LINE-1 DNA hypomethylation and radiation carcinogenesis., Competing Interests: The authors declare no conflict of interest.

Construal Level Theory states that psychologically proximal outcomes are construed concretely while psychologically distal outcomes are construed abstractly. Previous research suggests that the principles of Construal Level Theory can be applied to enhance self-control, as measured by delay discounting. The present studies replicate and expand on this work by examining whether theory-informed priming manipulations lead to delay discounting reductions in a repeated-measures design. Study 1 conceptually replicated previous work, with reduced delay discounting observed as a function of thinking abstractly. Studies 2 and 3 expanded on this work by reinterpreting (a) preference for immediate outcomes as preference for outcomes that are construed concretely, and (b) dispreference for delayed outcomes as dispreference for outcomes that are construed abstractly. Study 2 provided support for the first interpretation, as reduced delay discounting was observed as a function of thinking concretely about the future. Study 3 provided support for the second interpretation, as reduced delay discounting was observed as a function of thinking abstractly about the present. In studies 1 and 3, significant condition × order interactions were observed. In all three studies, the same impact of order of exposure to priming manipulation was observed, indicating specific carryover effects.

While it is generally believed that fetuses are at high risk of developing cancers, including leukemia, after low doses of radiation, it has been reported that atomic bomb survivors exposed in utero did not show a dose response for translocations in blood T lymphocytes when they were examined at approximately 40 years of age. Subsequent mouse studies confirmed that animals irradiated during the fetal stage did not show evidence of radiation effects in lymphocytes and bone marrow cells when they were examined after reaching adulthood. However, in a study of rat mammary epithelial cells, radiation effects were clearly observed after fetal irradiation. These results indicate that the fate of chromosome aberrations induced in a fetus could vary among different tissues. Here we report on translocation frequencies in mouse thyroid cells, which were irradiated at different stages of fetal development. Cytogenetic examination was conducted using fluorescence n situ hybridization (FISH) painting of chromosomes 1 and 3. Adult mice, 2 Gy X-ray irradiated at 15.5-day-old fetuses (E15.5), showed a higher translocation frequency (30/1,155 or 25.3 × 10 -3 ) than nonirradiated adult controls (0/1,007 or 0.1 × 10 -3 ), and was near that experienced by irradiated mothers and non-pregnant adult females (43/1,244 or 33.7 × 10 -3 ). These results are consistent with those seen in rat mammary cells. However, when fetuses were irradiated at an earlier stage of development (E6.5) before thyroid organogenesis, the resulting observed translocation frequency was much lower (3/502 or 5.8 × 10 -3 ) than that in E15.5 mice. These results suggest that after fetal irradiation, tissue stem cells record radiation effects primarily when the exposure occurs in cells that have been integrated into tissue. Embryonic stem cells that have been damaged prior to integration into the niche may undergo negative selection due to apoptosis, mitotic death or stem cell-niche cell interactions. The implications of these results in interpreting cancer risks after fetal irradiation are also discussed.

Episodic future thinking, which refers to the use of prospective imagery to concretely imagine oneself in future scenarios, has been shown to reduce delay discounting (enhance self-control). A parallel approach, in which prospective imagery is used to concretely imagine other's scenarios, may similarly reduce social discounting (i.e., enhance altruism). In study 1, participants engaged in episodic thinking about the self or others, in a repeated-measures design, while completing a social discounting task. Reductions in social discounting were observed as a function of episodic thinking about others, though an interaction with order was also observed. Using an independent-measures design in study 2, the effect of episodic thinking about others was replicated. Study 3 addressed a limitation of studies 1 and 2, the possibility that simply thinking about others decreased social discounting. Capitalizing on Construal Level Theory, which specifies that social distance and time in the future are both dimensions of a common psychological distance, we hypothesized that episodic future thinking should also decrease social discounting. Participants engaged in episodic future thinking or episodic present thinking, in a repeated-measures design, while completing a social discounting task. The pattern of results was similar to study 1, providing support for the notion that episodic thinking about psychologically distant outcomes (for others or in the future) reduces social discounting. Application of similar episodic thinking approaches may enhance altruism.

Background: The objective of this study was to investigate radiation effects on longitudinal pre-dementia cognitive decline among participants who developed dementia as well as on those who did not develop dementia during follow-up., Methods: Measuring cognitive function with the Cognitive Abilities Screening Instrument approximately every 2 years, we followed 1844 atomic bomb survivors participating in the Adult Health Study of the Radiation Effects Research Foundation from 1992 to 2011. Participants were adolescents or older when exposed to between 0 and 4 Gy. Approximately 15% and 40% of participants were exposed to ≥1 Gy and <5 mGy, respectively. At study start, participants were dementia-free and between 60 and 80 years old. Three-quarters of the participants returned after baseline, averaging 8.4 years of follow-up. During follow-up, 313 developed dementia. We used cognitive scores before dementia onset for analysis and a mixed-effects model to estimate radiation effects on longitudinal change of cognition, adjusting for dementia occurrence, age, sex, and education., Results: Cognition level was significantly associated with age, education, and dementia occurrence but not with radiation dose or sex. Cognitive decline accelerated with increasing age, especially among participants who developed dementia. Neither radiation nor education was significantly associated with the degree of deterioration with age. Radiation did not modify the different cognitive decline by dementia occurrence., Conclusions: Radiation did not significantly affect cognition among atomic bomb survivors exposed at or after adolescence., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Unlabelled: As our nation's population ages, the rates of chronic illness and disability are expected to increase significantly. Despite the knowledge that exercise may prevent chronic disease and promote health among older adults, many still are inactive. Factors related to exercise behaviors have been explored in recent years. However, temporal discounting is a motivational concept that has not been explored in regard to exercise in older adults. Temporal discounting is a decision making process by which an individual chooses a smaller more immediate reward over a larger delayed reward. The aim of this study was to determine if temporal discounting rates vary between exercising and non-exercising older adults., Design: This study used cross-sectional survey of 137 older adults living in the community. Older adults were recruited from 11 rural Arkansas churches. The Kirby delay-discounting Monetary Choice Questionnaire was used to collect discounting rates and then bivariate analysis was performed to compare temporal discounting rate between the exercisers and non-exercisers. Finally, multivariate analysis was used to compare discounting rate controlling for other covariates., Results: The results indicated that exercising older adults display lower temporal discounting rates than non-exercising older adults. After controlling for education, exercisers still have lower temporal discounting rates than non-exercisers (p<0.001)., Conclusions and Implications: These findings are important as several chronic health conditions relate to lack of exercise especially in older adults. This research suggests that if we can find appropriate incentives for discounting individuals, some type of immediate reward, then potentially we can design programs to engage and retain older adults in exercise., (Copyright © 2015 Elsevier Inc. All rights reserved.)