The effects of a heat acclimation protocol in persons with spinal cord injury

Persons without spinal cord injury (SCI) physiologically acclimate between seven to fourteen consecutive days of exercise in the heat. Decreased resting and exercise core temperature, decreased heart rate, increased plasma volume and increased thermal comfort during exercise are changes consistent with heat acclimation. Autonomic dysfunction after SCI impairs heat dissipation through sweating and vasodilation. The purpose of this study is to determine if seven consecutive days of exercise in the heat would result in physiologic changes consistent with heat acclimation in persons with SCI. Ten persons with SCI divided into two groups: tetraplegia (n=5) and paraplegia (n=5) exercised in 35 °C using an arm ergometer at 50% Wpeak for 30 min followed by 15 min rest. This protocol was repeated over seven consecutive days. Heart rate (HR), skin temperature, aural temperature (Taur), rate of perceived exertion (RPE), rate of perceived thermal strain (RPTS), and plasma volume (PV) were measured throughout the protocol. There were no significant differences in resting Taur exercise Taur, mean skin temperature, HR, PV, RPE or RPTS over the 7 days for either the tetraplegic or paraplegic group. Participants with SCI did not demonstrate the ability to dissipate heat more efficiently over 7 days of exercise at 35 °C. The lack of heat acclimation seen in persons with SCI has implications for the athlete and non-athlete alike. For the SCI athlete, inability to acclimate will impair performance and endurance especially in warm environments, compared to the person without SCI. For the SCI non-athlete, there is a greater risk of heat-related illness in warm environments that can negatively affect participation in outdoor activities and thus quality of life.NOTICE: this is the author’s version of a work that was accepted for publication inJournal of Thermal Biology. Changes resulting from the publishing process, such aspeer review, editing, corrections, structural formatting, and other quality controlmechanisms may not be reflected in this document. Changes may have been made tothis work since it was submitted for publication. A definitive version wassubsequently published in Journal of Thermal Biology [62, A (2016)] DOI:10.1016/j.jtherbio.2016.10.006© 2016, Elsevier. Licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International http://creativecommons.org/licenses/by-nc-nd/4.0

Cooling athletes with a spinal cord injury

Cooling strategies that help prevent a reduction in exercise capacity whilst exercising in the heat have received considerable research interest over the past 3 decades, especially in the lead up to a relatively hot Olympic and Paralympic Games. Progressing into the next Olympic/Paralympic cycle, the host, Rio de Janeiro, could again present an environmental challenge for competing athletes. Despite the interest and vast array of research into cooling strategies for the able-bodied athlete, less is known regarding the application of these cooling strategies in the thermoregulatory impaired spinal cord injured (SCI) athletic population. Individuals with a spinal cord injury (SCI) have a reduced afferent input to the thermoregulatory centre and a loss of both sweating capacity and vasomotor control below the level of the spinal cord lesion. The magnitude of this thermoregulatory impairment is proportional to the level of the lesion. For instance, individuals with high-level lesions (tetraplegia) are at a greater risk of heat illness than individuals with lower-level lesions (paraplegia) at a given exercise intensity. Therefore, cooling strategies may be highly beneficial in this population group, even in moderate ambient conditions (~21 °C). This review was undertaken to examine the scientific literature that addresses the application of cooling strategies in individuals with an SCI. Each method is discussed in regards to the practical issues associated with the method and the potential underlying mechanism. For instance, site-specific cooling would be more suitable for an athlete with an SCI than whole body water immersion, due to the practical difficulties of administering this method in this population group. From the studies reviewed, wearing an ice vest during intermittent sprint exercise has been shown to decrease thermal strain and improve performance. These garments have also been shown to be effective during exercise in the able-bodied. Drawing on additional findings from the able-bodied literature, the combination of methods used prior to and during exercise and/or during rest periods/half-time may increase the effectiveness of a strategy. However, due to the paucity of research involving athletes with an SCI, it is difficult to establish an optimal cooling strategy. Future studies are needed to ensure that research outcomes can be translated into meaningful performance enhancements by investigating cooling strategies under the constraints of actual competition. Cooling strategies that meet the demands of intermittent wheelchair sports need to be identified, with particular attention to the logistics of the sport

Evidence for host genetic regulation of altered lipid metabolism in experimental toxoplasmosis supported with gene data mining results

Toxoplasma gondii is one of the most successful parasites on Earth, infecting a wide array of mammals including one third of the global human population. The obligate intracellular protozoon is not capable of synthesizing cholesterol (Chl), and thus depends on uptake of host Chl for its own development. To explore the genetic regulation of previously observed lipid metabolism alterations during acute murine T. gondii infection, we here assessed total Chl and its fractions in serum and selected tissues at the pathophysiological and molecular level, and integrated the observed gene expression of selected molecules relevant for Chl metabolism, including its biosynthetic and export KEGG pathways, with the results of published transcriptomes obtained in similar murine models of T. gondii infection. The serum lipid status as well as the transcript levels of relevant genes in the brain and the liver were assessed in experimental models of acute and chronic toxoplasmosis in wild-type mice. The results showed that acute infection was associated with a decrease in Chl content in both the liver and periphery (brain, peripheral lymphocytes), and a decrease in Chl reverse transport. In contrast, in chronic infection, a return to normal levels of Chl metabolism has been noted. These changes corresponded to the brain and liver gene expression results as well as to data obtained via mining. We propose that the observed changes in Chl metabolism are part of the host defense response. Further insight into the lipid metabolism in T. gondii infection may provide novel targets for therapeutic agents

Strategies for conducting situated studies of technology use in hospitals

Ethnographic methods are widely used for understanding situated practices with technology. When authors present their data gathering methods, they almost invariably focus on the bare essentials. These enable the reader to comprehend what was done, but leave the impression that setting up and conducting the study was straightforward. Text books present generic advice, but rarely focus on specific study contexts. In this paper, we focus on lessons learnt by non-clinical researchers studying technology use in hospitals: gaining access; developing good relations with clinicians and patients; being outsiders in healthcare settings; and managing the cultural divide between technology human factors and clinical practice. Drawing on case studies across various hospital settings, we present a repertoire of ways of working with people and technologies in these settings. These include engaging clinicians and patients effectively, taking an iterative approach to data gathering and being responsive to the demands and opportunities provided by the situation. The main contribution of this paper is to make visible many of the lessons we have learnt in conducting technology studies in healthcare, using these lessons to present strategies that other researchers can take up

Intuitive geometry and visuospatial working memory in children showing symptoms of nonverbal learning disabilities.

Visuospatial working memory (VSWM) and intuitive geometry were examined in two groups aged 11-13, one with children displaying symptoms of nonverbal learning disability (NLD; n = 16), and the other, a control group without learning disabilities (n = 16). The two groups were matched for general verbal abilities, age, gender, and socioeconomic level. The children were presented with simple storage and complex-span tasks involving VSWM and with the intuitive geometry task devised by Dehaene, Izard, Pica, and Spelke (2006 ). Results revealed that the two groups differed in the intuitive geometry task. Differences were particularly evident in Euclidean geometry and in geometrical transformations. Moreover, the performance of NLD children was worse than controls to a larger extent in complex-span than in simple storage tasks, and VSWM differences were able to account for group differences in geometry. Finally, a discriminant function analysis confirmed the crucial role of complex-span tasks involving VSWM in distinguishing between the two groups. Results are discussed with reference to the relationship between VSWM and mathematics difficulties in nonverbal learning disabilities

Traditions of research into interruptions in healthcare: A conceptual review

Background Researchers from diverse theoretical backgrounds have studied workplace interruptions in healthcare, leading to a complex and conflicting body of literature. Understanding pre-existing viewpoints may advance the field more effectively than attempts to remove bias from investigations. Objective To identify research traditions that have motivated and guided interruptions research, and to note research questions posed, gaps in approach, and possible avenues for future research. Methods A critical review was conducted of research on interruptions in healthcare. Two researchers identified core research communities based on the community’s motivations, philosophical outlook, and methods. Among the characteristics used to categorise papers into research communities were the predominant motivation for studying interruptions, the research questions posed, and key contributions to the body of knowledge on interruptions in healthcare. In cases where a paper approached an equal number of characteristics from two traditions, it was placed in a blended research community. Results A total of 141 papers were identified and categorised; all papers identified were published from 1994 onwards. Four principal research communities emerged: epidemiology, quality improvement, cognitive systems engineering (CSE), and applied cognitive psychology. Blends and areas of mutual influence between the research communities were identified that combine the benefits of individual traditions, but there was a notable lack of blends incorporating quality improvement initiatives. The question most commonly posed by researchers across multiple communities was: what is the impact of interruptions? Impact was measured as a function of task time or risk in the epidemiology tradition, situation awareness in the CSE tradition, or resumption lag (time to resume an interrupted task) in the applied cognitive psychology tradition. No single question about interruptions in healthcare was shared by all four of the core communities. Conclusions Much research on workplace interruptions in healthcare can be described in terms of fundamental values of four distinct research traditions and the communities that bring the values and methods: of those research traditions to their investigations. Blends between communities indicate that mutual influence has occurred as interruptions research has progressed. It is clear from this review that there is no single or privileged perspective to study interruptions. Instead, these findings suggest that researchers investigating interruptions in healthcare would benefit from being more aware of different perspectives from their own, especially when they consider workplace interventions to reduce interruptions

Fatty acid in colorectal cancer in adult and aged patients of both sexes

Purpose: Colorectal cancer represents the second most common type of cancer in Serbia. Alteration of lipid metabolism begins early, and can represent a central hallmark in cancer evolution. Fatty acids have various important functions as building components of cell membranes, as signaling molecules in immune responses and also manage the general cancer signaling network. The purpose of this study was to investigate the difference of various fatty acids content between colorectal cancer and adjacent healthy intestinal tissue in adult and aged patients of both sexes. Methods: 52 subjects participated in this study. Healthy colon mucosa and tumor tissue samples were obtained from patients previously diagnosed with colorectal carcinoma. Simplified method of Berstad et al was used for direct transesterification of total lipids in tumor and healthy mucosa tissue samples and separations of the methyl esters was carried out using a gas chromatograph equipped with a split/ splitless injector and a flame ionization detector. Results: 18 0, 18 1 n7, 20 3, 20 4, 20 5, 22 4, 22 5 22 6, SFA, PUFA, n6, n3 and AA/EPA were significantly higher in tumor tissue. On the other hand, 18 1 n9, 18 2, 18 3 n3, MUFA, n6/ n3 were significantly higher in healthy tissue. Conclusions: Saturation index (SI) could be a valuable tool to delineate robust immune response and worse prognosis in patients with colorectal cancer. Our study demonstrated significant differences in fatty acid profiles between tumor tissue and healthy mucosa. Parameters, such as gender, age, stage and mucinous component didn't influence altered fatty acid content

HIV-Infected Patients as a Model of Aging

We appraised the relationship between the biological and the chrono- logical age and estimated the rate of biological aging in HIV-infected patients. Two independent biomarkers, the relative telomere length and iron metabolism parame- ters, were analyzed in younger (,35) and older (.50) HIV-infected and uninfected patients (control group). In our control group, telomeres of younger patients were significantly longer than telomeres of older ones. However, in HIV-infected partici- pants, the difference in the length of telomeres was lost. By combining the length of telomeres with serum iron, ferritin, and transferrin iron-binding capacity, a new for- mula for determination of the aging process was developed. The life expectancy of the healthy population was related to their biological age, and HIV-infected patients were biologically older. The effect of antiretroviral HIV drug therapies varied with respect to the biological aging process. IMPORTANCE This article is focused on the dynamics of human aging. Moreover, its interdisciplinary approach is applicable to various systems that are aging

Hafnium Resonance Parameter Analysis Using Neutron Capture and Transmission Experiments

The focus of this work is to determine the resonance parameters for stable hafnium isotopes in the 0.005 - 200 eV region, with special emphasis on the overlapping {sup 176}Hf and {sup 178}Hf resonances near 8 eV. Accurate hafnium cross sections and resonance parameters are needed in order to quantify the effects of hafnium found in zirconium, a metal commonly used in reactors. The accuracy of the cross sections and the corresponding resonance parameters used in current nuclear analysis tools are rapidly becoming the limiting factor in reducing the overall uncertainty on reactor physics calculations. Experiments measuring neutron capture and transmission are routinely performed at the Rensselaer Polytechnic Institute (RPI) LINAC using the time-of flight technique. {sup 6}Li glass scintillation detectors were used for transmission experiments at flight path lengths of 15 and 25 m, respectively. Capture experiments were performed using a sixteen section NaI multiplicity detector at a flight path length of 25 m. These experiments utilized several thicknesses of metallic and isotope-enriched liquid Hf samples. The liquid Hf samples were designed to provide information on the {sup 176}Hf and {sup 178}Hf contributions to the 8 eV doublet without saturation. Data analyses were performed using the R-matrix Bayesian code SAMMY. A combined capture and transmission data analysis yielded resonance parameters for all hafnium isotopes from 0.005 - 200 eV. Additionally, resonance integrals were calculated, along with errors for each hafnium isotope, using the NJOY and INTER codes. The isotopic resonance integrals calculated were significantly different than previous values. The {sup 176}Hf resonance integral, based on this work, is approximately 73% higher than the ENDF/B-VI value. This is due primarily to the changes to resonance parameters in the 8 eV resonance, the neutron width presented in this work is more than twice that of the previous value. The calculated elemental hafnium resonance integral however, changed very little

Exoskeletal-Assisted Walking in Veterans With Paralysis: A Randomized Clinical Trial

IMPORTANCE: Robotic exoskeletons leverage technology that assists people with spinal cord injury (SCI) to walk. The efficacy of home and community exoskeletal use has not been studied in a randomized clinical trial (RCT). OBJECTIVE: To examine whether use of a wheelchair plus an exoskeleton compared with use of only a wheelchair led to clinically meaningful net improvements in patient-reported outcomes for mental and physical health. DESIGN, SETTING, AND PARTICIPANTS: This RCT of veterans with SCI was conducted at 15 Veterans Affairs medical centers in the US from September 6, 2016, to September 27, 2021. Data analysis was performed from March 10, 2022, to June 20, 2024. INTERVENTIONS: Participants were randomized (1:1) to standard of care (SOC) wheelchair use or SOC plus at-will use of a US Food and Drug Administration (FDA)-cleared exoskeletal-assisted walking (EAW) device for 4 months in the home and community. MAIN OUTCOMES AND MEASURES: Two primary outcomes were studied: 4.0-point or greater improvement in the mental component summary score on the Veterans RAND 36-Item Health Survey (MCS/VR-36) and 10% improvement in the total T score of the Spinal Cord Injury-Quality of Life (SCI-QOL) physical and medical health domain and reported as the proportion who achieved clinically meaningful changes. The primary outcomes were measured at baseline, post randomization after advanced EAW training sessions, and at 2 months and 4 months (primary end point) in the intervention period. Device usage, reasons for not using, and adverse events were collected. RESULTS: A total of 161 veterans with SCI were randomized to the EAW (n = 78) or SOC (n = 83) group; 151 (94%) were male, the median age was 47 (IQR, 35-56) years, and median time since SCI was 7.3 (IQR, 0.5 to 46.5) years. The difference in proportion of successes between the EAW and SOC groups on the MCS/VR-36 (12 of 78 [15.4%] vs 14 of 83 [16.9%]; relative risk, 0.91; 95% CI, 0.45-1.85) and SCI-QOL physical and medical health domain (10 of 78 [12.8%] vs 11 of 83 [13.3%]; relative risk, 0.97; 95% CI, 0.44-2.15) was not statistically different. Device use was lower than expected (mean [SD] distance, 1.53 [0.02] miles per month), primarily due to the FDA-mandated companion being unavailable 43.9% of the time (177 of 403 instances). Two EAW-related foot fractures and 9 unrelated fractures (mostly during wheelchair transfers) were reported. CONCLUSIONS AND RELEVANCE: In this RCT of veterans with SCI, the lack of improved outcomes with EAW device use may have been related to the relatively low device usage. Solutions for companion requirements and user-friendly technological adaptations should be considered for improved personal use of these devices. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02658656