Environmental variability in aquatic ecosystems makes the study of ectotherms complex and challenging. Physiologists have historically overcome this hurdle in the laboratory by using 'average' ...conditions, representative of the natural environment for any given animal. Temperature, in particular, has widespread impact on the physiology of animals, and it is becoming increasingly important to understand these effects as we face future climate challenges. The majority of research to date has focused on the expected global average increase in temperature; however, increases in climate variability are predicted to affect animals as much or more than climate warming. Physiological responses associated with the acclimation to a new stable temperature are distinct from those in thermally variable environments. Our goal is to highlight these physiological differences as they relate to both thermal acclimation and the 'fallacy of the average' or Jensen's inequality using theoretical models and novel empirical data. We encourage the use of more realistic thermal environments in experimental design to advance our understanding of these physiological responses such that we can better predict how aquatic animals will respond to future changes in our climate.
IntroductionCommunity integration and social participation remain a challenge for many individuals following acquired brain injury (ABI) and the transition from hospital to home is a complex journey. ...It is important to conceptualise this transition from the perspective of people with ABI, to inform future research with the overall aim of improving the experience of community re-engagement and maintaining important relationships within social networks.Methods and analysisThe methodology outlined by Arksey and O’Malley and the Preferred Reporting Items for Systematic Reviews and Meta-Analysis: extension for Scoping Reviews will be used to guide the review. A comprehensive electronic database search will be conducted in MEDLINE, CINAHL, Scopus, Embase and PsychINFO. The search will aim to locate only published, qualitative or mixed methods studies and will be limited to citations published in English, from January 2014 to the date of final search completion. Quality assessment using the Critical Appraisal Skills Programme will be completed and reported.Data extraction will include participant and study characteristics.Finally, qualitative data from each citation, including participant quotes, will be extracted and thematic analysis will be completed to support conceptualisation of community participation from those who have experienced the transition to the community following discharge from hospital. Three individuals with lived experiences of ABI will be engaged as paid consultants to review and comment on the findings of the review.Ethics and disseminationIt is intended that the findings from this review will be made available to relevant stakeholders through peer-reviewed publications and conference presentations. This scoping review does not require an ethics application.
A new strategy is introduced combining the use of Multi-Criteria Optimization-based Trade-Off Exploration (TO) and RapidPlan™ (RP) for the selection of optimisation parameters that improve the ...trade-off between sparing of organs at risk (OAR) and target coverage for head and neck radiotherapy planning. Using both approaches simultaneously; three different workflows were proposed for the optimisation process of volumetric-modulated arc therapy (VMAT) plans. The generated plans were compared to the clinical plans and the plans that resulted using RP and TO individually.
Twenty clinical VMAT plans previously administered were selected. Five additional plans were created for each patient: a clinical plan further optimised with TO (Clin+TO); two plans generated by in-house built RP models, RP_1 with the model built with VMAT clinical plans and RP_TO with the model built with VMAT plans optimised by TO. Finally, these last two plans were additionally optimised with TO for the creation of the plans RP_1 + TO and RP_TO
respectively. The TO management was standardised to maximise the sparing of the parotid glands without compromising a clinically acceptable PTV coverage. Resulting plans were inter-compared based on dose-volume parameters for OAR and PTVs, target homogeneity, conformity, and plans complexity and deliverability.
The plans optimised using TO in combination with RP showed significantly improved OAR sparing while maintaining comparable target dose coverage to the clinical plans. The largest OAR sparing compared to the clinical plans was achieved by the RP_TO
plans, which reported a mean parotid dose average of 15.0 ± 4.6 Gy vs 22.9 ± 5.5 Gy (left) and 17.1 ± 5.0 Gy vs 24.8 ± 5.8 Gy (right). However, at the same time, RP_TO
showed a slight dose reduction for the 99% volume of the nodal PTV and an increase for the 95% (when comparing to the clinical plans 76.0 ± 1.2 vs 77.4 ± 0.6 and 80.9 ± 0.9 vs 79.7 ± 0.4) but remained within clinical acceptance. Plans optimised with RP and TO combined, showed an increase in complexity but were proven to be deliverable.
The use of TO combined with RP during the optimisation of VMAT plans enhanced plan quality the most. For the RP_TO
plans, acceptance of a slight deterioration in nodal PTV allowed the largest reduction in OAR dose to be achieved.
Randomized data assessing the longitudinal quality of life (QoL) impact of stereotactic ablative radiation therapy (SABR) in the oligometastatic setting are lacking.
We enrolled patients who had a ...controlled primary malignancy with 1 to 5 metastatic lesions, with good performance status and life expectancy >6 months. We randomized in a 1:2 ratio between standard of care (SOC) treatment (SOC arm) and SOC plus SABR to all metastatic lesions (SABR arm). QoL was measured using the Functional Assessment of Cancer Therapy-General. QoL changes over time and between groups were assessed with linear mixed modeling.
Ninety-nine patients were randomized. Median age was 68 years (range, 43-89), and 60% were male. The most common primary tumor types were breast (n = 18), lung (n = 18), colorectal (n = 18), and prostate (n = 16). Most patients (n = 92) had 1 to 3 metastases. Median follow-up was 26 months. Because of the previously reported inferior survival of the SOC arm, the time for attrition in QoL respondents to <10% of subjects was shorter in the SOC versus SABR arm (30 vs 42 months). In the whole cohort, QoL declined over time after randomization: There were significant declines in total Functional Assessment of Cancer Therapy-General score over time compared with baseline (P < .001) owing to declines in physical and functional subscales (both P < .001), with no declines in social and emotional subscales. However, the magnitudes of decline were small, and clinically meaningful changes were not seen at most time points. Comparison between arms showed no differences in QoL between the SABR and SOC arms in total score (P = .42) or in the physical (P = .98), functional (P = .59), emotional (P = .82), or social (P = .17) subscales.
For patients with oligometastases, average QoL declines slowly over time regardless of treatment approach, although the changes are small in magnitude. The use of SABR, compared with SOC, was not associated with a QoL detriment.
Malignant pleural mesothelioma (MPM) is a devastating disease with limited treatment options and a dismal prognosis. Attempts to employ radical radiotherapy in this disease have been limited by the ...complex shape of the pleura and the dose restrictions necessitated by the close proximity of radiosensitive structures. Recent shifts towards a ‘lung sparing’ surgical approach in MPM have further heightened these challenges. The aim of this systematic review is to assess recent advances in radiotherapy planning and delivery, to ascertain how these developments have impacted on the feasibility of delivering photon-based, high-dose radiotherapy with radical intent in MPM. Three electronic databases were searched and a total of 249 articles reviewed. The challenge of generating high quality, practice-defining data for diseases such as MPM was highlighted by the identification of just two randomised studies. Much of the literature consisted of low quality, retrospective data with small cohorts and inconsistent reporting on radiotherapy techniques and dosimetry. Nevertheless, a number of prospective phase II studies were identified to suggest that radical doses of radiotherapy can be delivered safely after a lung sparing procedure in MPM, reporting encouraging survival data and acceptable levels of toxicity.
Cold-water fishes are becoming increasingly vulnerable as changing thermal conditions threaten their future sustainability. Thermal stress and habitat loss from increasing water temperatures are ...expected to impact population viability, particularly for inland populations with limited adaptive resources. Although the long-term persistence of cold-adapted species will depend on their ability to cope with and adapt to changing thermal conditions, very little is known about the scope and variation of thermal tolerance within and among conspecific populations and evolutionary lineages. We studied the upper thermal tolerance and capacity for acclimation in three captive populations of brook trout (Salvelinus fontinalis) from different ancestral thermal environments. Populations differed in their upper thermal tolerance and capacity for acclimation, consistent with their ancestry: the northernmost strain (Lake Nipigon) had the lowest thermal tolerance, while the strain with the most southern ancestry (Hill’s Lake) had the highest thermal tolerance. Standard metabolic rate increased following acclimation to warm temperatures, but the response to acclimation varied among strains, suggesting that climatic warming may have differential effects across populations. Swimming performance varied among strains and among acclimation temperatures, but strains responded in a similar way to temperature acclimation. To explore potential physiological mechanisms underlying intraspecific differences in thermal tolerance, we quantified inducible and constitutive heat shock proteins (HSP70 and HSC70, respectively). HSPs were associated with variation in thermal tolerance among strains and acclimation temperatures; HSP70 in cardiac and white muscle tissues exhibited similar patterns, whereas expression in hepatic tissue varied among acclimation temperatures but not strains. Taken together, these results suggest that populations of brook trout will vary in their ability to cope with a changing climate.
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Dostopno za:
BFBNIB, DOBA, IZUM, KILJ, NMLJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
When faced with limited resources, juvenile salmonid fish form dominance hierarchies that result in social stress for socially subordinate individuals. Social stress, in turn, can have consequences ...for the ability of the fish to respond to additional stressors such as pathogens or exposure to pollutants. In the present study, the possibility that social stress affects the ability of rainbow trout (Oncorhynchus mykiss) to tolerate acute increases in water temperature was investigated. To this end, we first evaluated physiological and cellular stress responses following a 1 h heat shock in juvenile fish in dominance hierarchies. We measured stress hormone (cortisol and catecholamines) concentrations and blood, brain and liver tissue levels of three heat shock proteins (HSPs), the stress inducible HSP70, the constitutive HSC70 and HSP90, in dominant and subordinate trout. No effects of social status on the hormonal response to the heat stress were detected, but the cellular heat shock response in the brain and liver of dominant and subordinate individuals was inhibited. We then assessed thermal tolerance in dominant and subordinate fish through critical thermal maximum temperature (CT(max)) trials and measured HSPs following the heat shock. Subordinate fish were less thermally tolerant than their dominant counterparts. We conclude that social stress impacts the ability of fish to respond, on a cellular scale and in a tissue-specific manner, to increases in water temperature, with likely consequences for overall fitness.
Atlantic salmon populations are declining, and warming river temperatures in the summer months are thought to be a significant contributing factor. We describe the time course of cellular and ...metabolic responses to an ecologically relevant short-term thermal cycle in juvenile Atlantic salmon. We then examined whether this heat event would affect tolerance to a subsequent heat shock in terms of critical thermal maximum (CT max ). Fish induced heat shock protein 70 in red blood cells, heart, liver, and red and white muscle; whole blood glucose and lactate transiently increased during the heat cycle. In contrast, we observed no significant effect of a prior heat shock on CT max . The CT max was positively correlated with Fulton’s condition factor suggesting that fish with greater energy reserves are more thermally tolerant. Atlantic salmon activate cellular protection pathways in response to a single thermal cycle and appear to cope with this short-term, ∼1 d heat shock, but this challenge may compromise the ability to cope with subsequent heat events.
Chemical cues are of enormous importance in mediating the behaviour of animals, enabling them to navigate throughout their habitats, to detect the presence of predators or prey and for social ...recognition-identifying and discriminating between conspecifics. In many species of freshwater fish, social recognition is known to be based primarily on chemical cues. Such recognition mechanisms are vulnerable to disruption by the presence of anthropogenic contaminants in the aquatic environment. Here we show that acute exposure to low, environmentally relevant dosages of the ubiquitous contaminant, 4-nonylphenol, can seriously affect social recognition and ultimately social organization in fishes. A 1 hour 0.5 μg l−1 dose was sufficient to alter the response of members of a shoaling fish species (juvenile banded killifish, Fundulus diaphanus) to conspecific chemical cues. Dosages of 1-2 μg l−1 caused killifish to orient away from dosed conspecifics, in both a flow channel and an arena. Given the overall importance of shoaling as an adaptive strategy against predators and for locating food, it is likely that its disruption by anthropogenic contaminants would have serious implications for fishes' fitness.
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