9 research outputs found
Manipulating Testosterone to Assess Links between Behavior, Morphology, and Performance in the Brown Anole Anolis sagrei
Survival and reproductive success are determined by the complex interplay between behavior, physiology, morphology, and performance. When optimal trait combinations along these various phenotypic axes differ between sexes or across seasons, regulatory mechanisms such as sex steroids can often facilitate sexâspecific and/or seasonal trait expression. In this study, we used surgical castration and replacement of exogenous testosterone in adult male brown anoles (Anolis sagrei) to simultaneously examine the effects of testosterone on a suite of morphological (dewlap area, body size), physiological (immune function), behavioral (dewlap, head bob, and pushâup displays), and performance (stamina, sprint speed, bite force) traits. We show that testosterone increases (or castration reduces) growth rate, dewlap area, and bite force. Treatment effects on bite force may simply reflect underlying treatment differences in growth combined with allometry of bite force. Other traits, such as stamina, sprint speed, and rate of behavioral displays, were largely independent of circulating testosterone levels. Although we did not observe significant treatment effects on immune function, we found negative correlations between growth and immune function consistent with the hypothesis that testosterone mediates tradeâoffs between these competing aspects of energy allocation. Overall, our results demonstrate that testosterone can exert pleiotropic effects on a variety of morphological, physiological, behavioral, and performance traits that are known to influence survival and reproductive success
Recommended from our members
Participation in physical activity in patients 1â4 years post total joint replacement in the Dominican Republic
Background: To address both the growing burden of joint disease and the gaps in medical access in developing nations, medical relief organizations have begun to launch programs to perform total joint replacement (TJR) on resident populations in developing countries. One outcome of TJR of particular interest is physical activity (PA) since it is strongly linked to general health. This study evaluates the amount of postoperative participation in PA in low-income patients who received total joint replacement in the Dominican Republic and identifies preoperative predictors of postoperative PA level. Methods: We used the Yale Physical Activity Survey (YPAS) to assess participation in postoperative PA 1â4 years following total knee or hip replacement. We compared the amount of aerobic PA reported by postoperative TJR patients with the levels of PA recommended by the CDC and WHO. We also analyzed preoperative determinants of postoperative participation in aerobic PA in bivariate and multivariate analyses. Results: 64 patients out of 170 eligible subjects (52/128 TKR and 14/42 THR) who received TJR between 2009â2012 returned for an annual follow-up visit in 2013, with a mean treatment-to-follow-up time of 2.1 years. 43.3% of respondents met CDC/WHO criteria for sufficient participation in aerobic PA. Multivariate analyses including data from 56 individuals identified that patients who were both younger than 65 and at least two years postoperative had an adjusted mean activity dimensions summary index (ADSI) 22.9 points higher than patients who were 65 or older and one year postoperative. Patients who lived with friends or family had adjusted mean ADSI 17.2 points higher than patients living alone. Patients who had the most optimistic preoperative expectations of outcome had adjusted mean ADSI scores that were 19.8 points higher than those who were less optimistic. Conclusion: The TJR patients in the Dominican cohort participate in less PA than recommended by the CDC/WHO. Additionally, several associations were identified that potentially affect PA in this population; specifically, participants who are older than 65, recently postoperative, less optimistic about postoperative outcomes and who live alone participate in less PA
Development and validation of a Spanish translation of the Yale activity questionnaire
Background: Valid measures of physical activity are critical research tools. The objective of this study was to develop a Spanish translation of the Yale Physical Activity Survey, and to provide preliminary evidence of its validity in a population of Dominican patients with lower extremity arthritis. Methods: A Dominican bilingual health care professional translated the Yale Physical Activity Survey (YPAS) from English to Spanish. Several Dominican adults reviewed the translation to ensure it was linguistically and culturally appropriate. The questionnaire was back-translated to English by a North American researcher who is fluent in Spanish. Discrepancies between the original and back-translated versions were resolved by the translator and back-translator. The Spanish translation was administered to 108 Dominican subjects with advanced hip or knee arthritis prior to (N = 44) or one to four years following (N = 64) total joint replacement. We assessed construct validity by examining the association of YPAS scores and measures of functional status and pain (WOMAC), quality of life (EQ-5D) and the number of painful lower extremity joints. Results: A higher YPAS Part II Activity Dimensions Summary Index score had weak to modest correlations with worse function and quality of life as measured with the WOMAC function scale (r = 0.21, p = 0.03), SF-36 Physical Activity Scale (r = 0.29, p = 0.004) and EQ-5D (r = 0.34, p = 0.0007). Total minutes of vigorous activity and walking had weak to modest correlation with these measures (WOMAC Function Scale (r = 0.15, p = 0.15), SF-36 Physical Activity Scale (r = 0.21, p = 0.04) and EQ-5D utility (r = 0.24, p = 0.02)). Correlations between the YPAS Part I energy expenditure score and these measures were lower (WOMAC Function Scale (r = 0.07, p = 0.49), SF-36 Physical Activity Scale (r = 0.03, p = 0.74) and EQ-5D utility (r = 0.18, p = 0.07)). Conclusions: We have developed a new Spanish translation of the Yale Physical Activity Survey and provided evidence of convergent validity in a sample of Dominican patients prior to or 1â4 years following total joint replacement
Entrapment of the urinary bladder: A rare mechanism of bladder injury in pelvic trauma
A pelvic fracture with entrapment of the urinary bladder in the fracture site is a rare pattern of injury. As the âteam captainsâ in the trauma bay and in the care of polytraumatized patients, trauma surgeons must be aware of this entity and its implications. We report a case of acute bladder entrapment in the fracture site of a lateral compression pelvic fracture. A review of the English literature yielded four previous reports, including two patients with delayed diagnosis (Ghuman et al., 2014; Kumar et al., 1980; Wright and Taitsman, 1996; Min et al., 2010 [1â4]).Kumar and colleagues first documented bladder entrapment by a pelvic fracture in 1980 (Kumar et al., 1980 [2]). Ghuman et al. described a similar case treated with fixation of the pelvic fracture (Ghuman et al., 2014 [1]). Wright and colleagues treated a patient with bladder perforation due to entrapment diagnosed two weeks after a pelvic ring fracture (Wright and Taitsman, 1996 [3]). In this case the bladder injury was repaired, but internal fixation of the pelvis fracture was avoided due to fear of contamination. Finally, Min et al. documented a case of bladder entrapment and perforation presenting six months after non-operative management of a pelvic ring fracture. The female patient developed recurrent UTIs and dyspareunia, and imaging revealed fracture malunion with the bladder entrapped in the fracture site (Min et al., 2010 [4]).This collection of case reports demonstrates the potential for acute or delayed bladder injury even in seemingly benign pelvic fractures. A high index of suspicion is required to intervene and prevent morbidity from bladder injuries in pelvic trauma. Entrapment of the bladder may require surgical intervention even when the injury pattern would not normally dictate surgery for the pelvis or bladder alone (Bryk and Zhao, 2016 [5]). We describe the diagnosis and surgical management of bladder entrapment and present a brief review of bladder injuries associated with pelvic fractures. Keywords: Trauma surgery, Pelvic fracture, Bladder entrapment, Pelvic trauma, Genitourinary traum
Reliability and Accuracy of Cross-sectional Radiographic Assessment of Severe Knee Osteoarthritis: Role of Training and Experience
OBJECTIVE: To determine the reliability of radiographic assessment of knee osteoarthritis (OA) by non-clinician readers compared to an experienced radiologist. METHODS: The radiologist trained three non-clinicians to evaluate radiographic characteristics of knee OA. The radiologist and non-clinicians read preoperative films of 36 patients prior to total knee replacement. Intra- and inter-reader reliability was measured using the weighted kappa statistic and intra-class correlation coefficient (ICC). Kappa <0.20 indicated slight agreement, 0.21 â 0.40 fair, 0.41 â 0.60 moderate, 0.61 â 0.80 substantial, and 0.81 â 1.0 almost perfect agreement. RESULTS: Intra-reader reliability among non-clinicians (kappa) ranged from 0.40 to 1.0 for individual radiographic features and 0.72 to 1.0 for Kellgren-Lawrence (K-L) grade. ICCs ranged from 0.89 to 0.98 for the Osteoarthritis Research Society International (OARSI) Summary Score. Inter-reader agreement among non-clinicians ranged from kappa of 0.45 to 0.94 for individual features, and 0.66 to 0.97 for K-L grade. ICCs ranged from 0.87 to 0.96 for the OARSI Summary Score. Inter-reader reliability between non-clinicians and the radiologist ranged from kappa of 0.56 to 0.85 for KL grade. ICCs ranged from 0.79 to 0.88 for the OARSI Summary Score. CONCLUSION: Intra- and inter-rater agreement was variable for individual radiograph features but substantial for summary KL grade and OARSI Summary Score. Investigators face trade-offs between cost and reader experience. These data suggest that in settings where costs are constrained, trained non-clinicians may be suitable readers of radiographic knee OA, particularly if a summary score (K-L grade or OARSI Score) is used to capture radiographic severity