Factors affecting populations of the endemic Iberian hare (Lepus granatensis) after the first myxomatosis outbreaks in Central Spain

The Iberian hare (Lepus granatensis) is an endemic species distributed in Spain and Portugal. Myxomatosis outbreaks affecting this species were detected in 2018 in Central and Southern Spain, spreading afterward. Aiming to evaluate factors affecting the status of hare population after the arrival of myxomatosis, we conducted 108 nocturnal hare counts in Central Spain during two study periods (winter/spring and summer/autumn) in 54 different hunting grounds, covering 1071 km and observing 884 individuals. The mean density in winter/spring was 7.66 hares/100 ha, (range 6.14-9.54/100 ha), while in summer/autumn, it was 3.4 hares/100 ha (range 2.6-4.4/100 ha). Densities of hares were not affected by the dominant habitat and the presence/absence of myxomatosis outbreaks. Hares were more abundant at hunting grounds at a higher altitude and in those conducting targeted management, while detection of myxomatosis was related to lower altitude and higher levels of game management. A MaxEnt model used to generate a risk map for myxomatosis occurrence showed that the temperature annual range was the most important predictor, which suggests that environmental factors affecting myxomatosis vectors (mosquitoes, fleas, and ticks) could play a key role in disease transmission. As myxomatosis in hares is becoming endemic, hare densities may be improved by game management and the monitoring and surveillance of this emerging disease. These surveillance programs could be the basis of effective collaborations between hunters, researchers, and environmental managers.

Diagnostic utility and therapeutic impact of PET/CT [18F]F-Fluoromethylcholine -Choline in the biochemical recurrence of prostate cancer

OBJECTIVE

To assess the diagnostic capability of PET/CT with [¹⁸F]F-Fluoromethylcholine in prostate cancer (PC) with biochemical recurrence and its therapeutic impact.

MATERIAL AND METHODS

We included 108 patients, diagnosed with PC with biochemical criteria for recurrence. A PET/CT Choline scan was performed by dynamic pelvic and whole body study at 60min post-tracer injection. The relationship between the positive studies and the PSA value was analysed by classifying patients into three groups (<1.2/1.2-2/>2ng/ml), and the diagnostic capacity was assessed with respect to pelvic MRI and the impact on the therapeutic decision.

RESULTS

The location of recurrence was identified in 85 of 108 patients (78.7%): 34 local, 47 pelvic lymph nodes and 58 distant lesions, including retroperitoneal, mediastinal lymph nodes and distant organ lesions (bone and lung). Second tumors were diagnosed in 4 patients. No significant differences were found in the percentage of positive studies depending on primary treatment. Patients with PSA>2ng/ml showed a higher percentage of disease detection than patients with a lower PSA level, with significant differences (p<0.0001). PET/CT [¹⁸F]F-Choline was able to detect local disease, not previously known from MRI, in 29.41% of patients. PET/CT Choline had an impact on therapeutic management in 67 of 108 patients (62%).

CONCLUSIONS

PET/CT with [¹⁸F]F-Fluoromethylcholine is a useful tool in the detection of locoregional and disseminated disease of PC treated with suspicion of recurrence, providing a change in therapeutic management in 62% of patients.

Postoperative adjuvant and very early salvage radiotherapy after prostatectomy in high-risk prostate cancer patients can improve specific and overall survival

PURPOSE

Adjuvant radiotherapy (ART) for biochemical relapse (BR) after radical prostatectomy (RP) showed increased disease-free survival (DFS) in three previous randomized trials. Retrospective phase II trials evaluated if early salvage RT (ESRT) is equivalent to ART. Our study aims to compare ART and ESRT to salvage RT.

MATERIALS AND METHODS

We compared RP plus ART and ESRT versus SRT. Indication for RT was made by PSA determination after RP: ART when PSA ≤ 0.2 ng/ml, ESRT when PSA ≤ 0.3 after PSA rise from 0.0 to SRT PSA ≥ 0.3. The cause of death of each patients was analyzed, DFS, cause-specific survival (CSS) overall survival (OS) and metastasis-free survival (MFS) in relation to RT intention.

RESULTS

Between 1993 and 2008, 204 patients with a median age of 65 years (44-75) were treated. The median follow-up was 160 months (28.1-273.3). At diagnosis, 89.7% had localized clinical stages and 90.2% had Gleason (G) ≤ 7. The median PSA was 10 (range 4-101). The postoperative G was ≥ 7 in 66.2%; 56.4% had ≥ 2 positive margins; 29.4% received ART, 20% ESRT and 59.3% SRT. The DFS for ART, ESRT and SRT was 74, 56 and 39% with significant differences between the three groups (p < 0.001). ART + ESRT were combined versus SRT; for the DFS, the significant differences (p < 0.001) remained 67% versus 39%. Positive margins, pT3 and pre-RT PSA were significant factors on multivariate analysis. The CSS in the ART + ESRT group was 92 vs. 78% in the SRT group (p < 0.05). OS was 69% in ART + ESRT vs. 57% in SRT (p < 0.05). MFS was 82.7% in ART + ESRT vs. 67.4% in SRT.

CONCLUSIONS

In this study the ART + ESRT presented benefits versus SRT in DFS, CSS, OS and MFS.

The fractal dimension of a conspicuous ornament varies with mating status and shows assortative mating in wild red-legged partridges (Alectoris rufa)

Complex body designs, such as plumage ornaments in birds, can be described by fractal geometry. These complex patterns could have a role as visual signals during courtship and social interactions, but an empirical validation in the wild is currently lacking. Here, we investigated whether the fractal dimension (FD) of a complex plumage pattern displayed by red-legged partridges Alectoris rufa could function as a potential sexual signal. We captured wild birds early in the breeding season and tested if mated and unmated birds differed in the FD of their conspicuous melanin-based black bib. We also tested if the FD of the black bib was correlated within the pair, looking for evidence of assortative mating based on the expression of this trait. We simultaneously assessed similar effects in other ornamental traits (black bib size, white throat patch and black flank band surface, redness of the eye rings and bill). Mated birds showed higher black bib FD values than unmated ones. Mated males, but not females, also displayed a larger black bib. Moreover, the black bib FD (but not the trait size) and the white throat patch surface showed assortative mating. Finally, females with higher black bib FD showed smaller black flank band surface, suggesting a trade-off in the expression of the two melanin-pigmented plumage traits. This provides unique and novel indication for the shape complexity of a pigmented trait, here described by its fractal dimension, to be potentially under sexual selection in a wild animal.

Intraspecific and interspecific competition induces density-dependent habitat niche shifts in an endangered steppe bird

Interspecific competition is a dominant force in animal communities that induces niche shifts in ecological and evolutionary time. If competition occurs, niche expansion can be expected when the competitor disappears because resources previously inaccessible due to competitive constraints can then be exploited (i.e., ecological release). Here, we aimed to determine the potential effects of interspecific competition between the little bustard (Tetrax tetrax) and the great bustard (Otis tarda) using a multidimensional niche approach with habitat distribution data. We explored whether the degree of niche overlap between the species was a density‐dependent function of interspecific competition. We then looked for evidences of ecological release by comparing measures of niche breadth and position of the little bustard between allopatric and sympatric situations. Furthermore, we evaluated whether niche shifts could depend not only on the presence of great bustard but also on the density of little and great bustards. The habitat niches of these bustard species partially overlapped when co‐occurring, but we found no relationship between degree of overlap and great bustard density. In the presence of the competitor, little bustard's niche was displaced toward increased use of the species' primary habitat. Little bustard's niche breadth decreased proportionally with great bustard density in sympatric sites, in consistence with theory. Overall, our results suggest that density‐dependent variation in little bustard's niche is the outcome of interspecific competition with the great bustard. The use of computational tools like kernel density estimators to obtain multidimensional niches should bring novel insights on how species' ecological niches behave under the effects of interspecific competition in ecological communities.

Pharmacological modulation of LMNA SRSF1-dependent splicing abrogates diet-induced obesity in mice

Bakground/Objectives:Intense drug discovery efforts in the metabolic field highlight the need for novel strategies for the treatment of obesity. Alternative splicing (AS) and/or polyadenylation enable the LMNA gene to express distinct protein isoforms that exert opposing effects on energy metabolism and lifespan. Here we aimed to use the splicing factor SRSF1 that contribute to the production of these different isoforms as a target to uncover new anti-obesity drug.

SUBJECTS/METHODS

Small molecules modulating SR protein activity and splicing were tested for their abilities to interact with SRSF1 and to modulate LMNA (AS). Using an LMNA luciferase reporter we selected molecules that were tested in diet-induced obese (DIO) mice. Transcriptomic analyses were performed in the white adipose tissues from untreated and treated DIO mice and mice fed a chow diet.

RESULTS

We identified a small molecule that specifically interacted with the RS domain of SRSF1. ABX300 abolished DIO in mice, leading to restoration of adipose tissue homeostasis. In contrast, ABX300 had no effect on mice fed a standard chow diet. A global transcriptomic analysis revealed similar profiles of white adipose tissue from DIO mice treated with ABX300 and from untreated mice fed a chow diet. Mice treated with ABX300 exhibited an increase in O₂ consumption and a switch in fuel preference toward lipids.

CONCLUSIONS

Targeting SRSF1 with ABX300 compensates for changes in RNA biogenesis induced by fat accumulation and consequently represents a novel unexplored approach for the treatment of obesity.

Evidence-based recommendations of postoperative radiotherapy in lung cancer from Oncologic Group for the Study of Lung Cancer (Spanish Radiation Oncology Society)

Locally advanced non-small cell lung cancer (NSCLC) is a diversified illness in which postoperative radiation therapy (PORT) for complete resection with positive hiliar (pN1) and/or mediastinal (pN2) lymph nodes is controversial. Although several studies have shown that PORT has beneficial effects, randomized trials are needed to demonstrate its impact on overall survival. In this review, the Spanish Radiation Oncology Group for Lung Cancer describes the most relevant literature on PORT in NSCLC patients stage pN1-2. In addition, we have outlined the current recommendations of different national and international clinical guidelines and have also specified practical issues regarding treatment volume definition, doses and fractionation.

A resource-based modelling framework to assess habitat suitability for steppe birds in semiarid Mediterranean agricultural systems

European agriculture is undergoing widespread changes that are likely to have profound impacts on farmland biodiversity. The development of tools that allow an assessment of the potential biodiversity effects of different land-use alternatives before changes occur is fundamental to guiding management decisions. In this study, we develop a resource-based model framework to estimate habitat suitability for target species, according to simple information on species’ key resource requirements (diet, foraging habitat and nesting site), and examine whether it can be used to link land-use and local species’ distribution. We take as a study case four steppe bird species in a lowland area of the north-eastern Iberian Peninsula. We also compare the performance of our resource-based approach to that obtained through habitat-based models relating species’ occurrence and land-cover variables. Further, we use our resource-based approach to predict the effects that change in farming systems can have on farmland bird habitat suitability and compare these predictions with those obtained using the habitat-based models. Habitat suitability estimates generated by our resource-based models performed similarly (and better for one study species) than habitat based-models when predicting current species distribution. Moderate prediction success was achieved for three out of four species considered by resource-based models and for two of four by habitat-based models. Although, there is potential for improving the performance of resource-based models, they provide a structure for using available knowledge of the functional links between agricultural practices, provision of key resources and the response of organisms to predict potential effects of changing land-uses in a variety of context or the impacts of changes such as altered management practices that are not easily incorporated into habitat-based models.

Effect of Game Management on Wild Red-Legged Partridge Abundance

The reduction of game and fish populations has increased investment in management practices. Hunting and fishing managers use several tools to maximize harvest. Managers need to know the impact their management has on wild populations. This issue is especially important to improve management efficacy and biodiversity conservation. We used questionnaires and field bird surveys in 48 hunting estates to assess whether red-legged partridge Alectoris rufa young/adult ratio and summer abundance were related to the intensity of management (provision of supplementary food and water, predator control and releases of farm-bred partridges), harvest intensity or habitat in Central Spain. We hypothesized that partridge abundance would be higher where management practices were applied more intensively. Variation in young/adult ratio among estates was best explained by habitat, year and some management practices. Density of feeders and water points had a positive relationship with this ratio, while the density of partridges released and magpies controlled were negatively related to it. The variables with greatest relative importance were feeders, releases and year. Variations in post-breeding red-legged partridge abundance among estates were best explained by habitat, year, the same management variables that influenced young/adult ratio, and harvest intensity. Harvest intensity was negatively related to partridge abundance. The other management variables had the same type of relationship with abundance as with young/adult ratio, except magpie control. Variables with greatest relative importance were habitat, feeders, water points, releases and harvest intensity. Our study suggests that management had an overall important effect on post-breeding partridge abundance. However, this effect varied among tools, as some had the desired effect (increase in partridge abundance), whereas others did not or even had a negative relationship (such as release of farm-reared birds) and can be thus considered inefficient or even detrimental. We advise reconsidering their use from both ecological and economical points of view.

Metabolic intervention on lipid synthesis converging pathways abrogates prostate cancer growth

One of the most conserved features of all cancers is a profound reprogramming of cellular metabolism, favoring biosynthetic processes and limiting catalytic processes. With the acquired knowledge of some of these important changes, we have designed a combination therapy in order to force cancer cells to use a particular metabolic pathway that ultimately results in the accumulation of toxic products. This innovative approach consists of blocking lipid synthesis, at the same time that we force the cell, through the inhibition of AMP-activated kinase, to accumulate toxic intermediates, such as malonyl-coenzyme A (malonyl-CoA) or nicotinamide adenine dinucleotide phosphate. This results in excess of oxidative stress and cancer cell death. Our new therapeutic strategy, based on the manipulation of metabolic pathways, will certainly set up the basis for new upcoming studies defining a new paradigm of cancer treatment.

Unitary transformations depending on a small parameter

We formulate a unitary perturbation theory for quantum mechanics inspired by the Lie-Deprit formulation of canonical transformations. The original Hamiltonian is converted into a solvable one by a transformation obtained through a Magnus expansion. This ensures unitarity at every order in a small parameter. A comparison with the standard perturbation theory is provided. We work out the scheme up to order ten with some simple examples.

Condition- and parasite-dependent expression of a male-like trait in a female bird

In many species, females display brightly coloured and elaborate traits similar to those that males use in intra- and inter-sexual selection processes. These female characters are sometimes related to fitness, and might function as secondary sexual characteristics that have evolved through sexual selection. Here, we used descriptive data from 674 females in 10 populations and an experimental removal of Trichostrongylus tenuis parasites in four populations, to examine the effects of season, age, condition, and parasites on the size of supra-orbital combs displayed by female red grouse Lagopus lagopus scoticus. We found that comb size (i) was greater during the breeding than the non-breeding season, (ii) was greater in adult than in young females, (iii) was positively correlated with body condition, and (iv) negatively correlated with parasite abundance. Experimentally, we showed that comb size increased proportionally to the number of worms removed after parasite dosing. Our findings provide a better understanding of proximate mechanisms behind the expression of a male-like trait in females, and we discuss its possible function as a female ornament.

Spanish radiobiological pattern of care in lung cancer: a GOECP/SEOR study

INTRODUCTION

A survey regarding radiobiological questions in the treatment of lung cancer (LC) was done to study the clinical aspects of radiotherapy in Spain, in order to standardise treatment decisions.

METHODS AND MATERIALS

From November 2007 to March 2008, a survey was performed among radiation oncologists in Spain specialising in LC treatment via e-mail, which included questions regarding different radiobiological aspects of radiotherapy LC treatment. The extent of the resulting material made it necessary to divide it into two parts; the first is presented in this article. The second, which includes items about alpha/beta-NTCP/TCP values and reirradiation criteria, will be reported elsewhere.

RESULTS

Thirty-one radiation therapists from 29 radiation oncology departments answered the survey. 77.4-93.5% of responders used the basic formula from the linear-quadratic model and/or computer software for radiobiological calculations; 100% used lung (mostly V20, median <30%) and spinal cord constraints (mostly a median of physical maximum dose <45.5 Gy); and 90.3% used heart and oesophagus constraints (very heterogeneous parameters in both organs).

CONCLUSIONS

Radiobiological considerations are clearly present in the planning process of radiotherapy of LC in Spain, with a high coincidence with the literature regarding lung and spinal cord constraints. The heterogeneity shown for oesophagus and heart results demonstrates the need for continuing investigation into the standardisation of clinical, dosimetric and radiobiologic aspects of the treatment of this cancer.

Longitudinal rotation: an unrecognised motion pattern in patients with dilated cardiomyopathy

BACKGROUND

Heart failure patients who are candidates for CRT frequently display longitudinal rotation (LR) - a swinging motion of the heart when imaged in a horizontal long-axis plane.

OBJECTIVES

To identify the magnitude and predictors of LR in patients with ischaemic (ICM) and idiopathic dilated (DCM) cardiomyopathy, and to assess predictive value of LR in patients undergoing cardiac resynchronisation therapy (CRT).

DESIGN AND SETTING

A retrospective study in a tertiary heart care setting.

METHODS

Echocardiography was performed in 45 ICM and 41 DCM patients who were CRT candidates and 16 control subjects. Global LR, segmental strains and segmental LR were assessed from echocardiograms using speckle tracking. Repeat echocardiography >40 days after the beginning of CRT was performed in 64 patients.

RESULTS

While DCM patients with QRS duration of both <130 ms and > or =130 ms displayed significant clockwise LR (p<0.001 for both vs 0), ICM patients and control subjects had LR that did not differ from 0. The most significant LR predictor was end-diastolic volume (p<0.001) followed by the absence of ischaemia (p<0.001) and QRS duration (p = 0.05). DCM patients with prominent clockwise LR had lower septal but higher lateral strains than DCM patients with minimal LR, or ICM patients with counterclockwise LR. LR correlated with decrease of end-systolic volume in DCM (r = 0.49, p = 0.004), while no relationship was observed in ICM.

CONCLUSION

Clockwise LR is linked to presence of DCM, with the small impact of QRS duration. LR is a moderately strong predictor of end-systolic volume decrease during CRT in DCM.