Testing metabolic cold adaptation and the climatic variability hypothesis in two latitudinally distant populations of a supratidal water beetle.

Temperature significantly impacts ectotherm physiology, with thermal tolerance and metabolic traits typically varying with latitude across species ranges. The drivers of this variation remain unclear, however, despite obvious consequences for population persistence and conservation in the face of ongoing global change. This study explored local adaptation and phenotypic plasticity of metabolic rates and thermal limits in the supratidal rockpool beetle Ochthebius lejolisii. Using populations from localities at different ends of the species range that experience contrasting thermal variability, we simultaneously tested two of the major paradigms of spatial physiological ecology: metabolic cold adaptation (MCA) and the climatic variability hypothesis (CVH). Reciprocal acclimation was conducted under spring temperature regimes of both localities, incorporating local diurnal variation. Metabolic rates were measured by closed respirometry, and thermal tolerance limits estimated through thermography. In line with MCA, the higher-latitude population (colder climate) showed higher metabolic rates and temperature coefficients (Q10s) at lower temperatures than the lower-latitude population. As predicted by the CVH, the lower-latitude population (more variable climate) showed higher upper thermal tolerance but only the higher-latitude population was able to acclimate upper thermal limits. This result suggests trade-offs between physiological thermal limits and thermal plasticity in this species. A limited acclimation capacity could make populations on Mediterranean coasts especially vulnerable in the face of projected increases in extreme temperatures under ongoing climate change.

The diagnosis and management of respiratory tract fungal infection in cystic fibrosis: A UK survey of current practice.

Aspergillus fumigatus is commonly found in the airways of patients with cystic fibrosis (CF), and allergic bronchopulmonary aspergillosis (ABPA) is the most recognized associated clinical condition. However, accurate diagnosis remains challenging, and there is a paucity of clinical trials to guide clinical management of fungal disease. The aim of this survey was to assess the variability in current practice across the UK in diagnosis and management of fungal lung disease in CF patients. A 21 question anonymous online survey was sent to 94 paediatric and adult CF consultants in the UK. The response rate was 60.6% (32 adult physicians, 25 pediatricians) with 55 full and 2 partially completed surveys. For a first diagnosis of ABPA 20 (35.1%) treat with prednisolone alone, 38 (66.7%) use prednisolone with itraconazole and 2 (3.5%) choose voriconazole. Only 5 (8.8%) treat with prednisolone alone for a 1st relapse, 33 (58%) used prednisolone with itraconazole. To reduce treatment, 21 (36.8%) decrease steroids to zero over time and maintain azole therapy, 18 (31.6%) stop the azole and steroid after a fixed time, and 5 (8.8%) stop the azole after a fixed time and maintain a small steroid dose. Thirty-eight (66.7%) respondents believe Aspergillus colonization of the airway can cause clinical deterioration, and 37 (66.1%) would treat this. Scedosporium apiospermum infection has been diagnosed and treated by 35 (61.4%) of respondents. Results of this survey highlight the variance in clinical practice and the limited evidence available to guide management of fungal infection in CF.

The outcome of pregnancies in women with cystic fibrosis--single centre experience 1998-2011.

OBJECTIVE: To describe the maternal and fetal outcomes of pregnancies in women with cystic fibrosis. DESIGN: Retrospective study. SETTING: Single obstetric hospital and adult cystic fibrosis centre. METHODS: Retrospective case-note review of pregnant women with cystic fibrosis referred for antenatal care and delivery. MAIN OUTCOME MEASURES: Maternal and fetal outcomes, mode of delivery, lung function and pregnancy complications. RESULTS: Forty-eight pregnancies were studied in 41 women. There were two miscarriages, 44 singleton pregnancies and two sets of twins. All babies were liveborn and survived. The mean gestational age at delivery was 35.9 ± 3.3 weeks. There were no fetal abnormalities or terminations of pregnancy. The median birthweight centile was 31.9 (interquartile range 14.9-55.6). Twenty-five (52.1%) of the women had pancreatic insufficiency and 17 (35.4%) required insulin. There was a positive correlation between booking predicted forced expiratory volume in 1 second (FEV(1) ) and gestational age at delivery (P < 0.01). Women with FEV(1) ≤60% were more likely to deliver earlier and by caesarean section compared with women with FEV(1) >60% (35.0 ± 3.2 weeks versus 37.1 ± 3.0 weeks; P = 0.02 and 75.0% versus 25.0%; P = 0.01). Three of the seven women with an FEV(1) <40% died within 18 months of delivery. Four of the eight women with FEV(1) 40-50% died between 2 and 8 years after delivery. CONCLUSION: Pregnancy for women with cystic fibrosis is possible and results in favourable maternal and fetal outcomes, but the incidence of preterm delivery and caesarean section is increased. Women with pre-existing poor lung function should be counselled antenatally to ensure that they understand the implications of their shortened life-expectancy and parenthood.

Population genetic structure and long-distance dispersal among seabird populations: implications for colony persistence.

Dramatic local population decline brought about by anthropogenic-driven change is an increasingly common threat to biodiversity. Seabird life history traits make them particularly vulnerable to such change; therefore, understanding population connectivity and dispersal dynamics is vital for successful management. Our study used a 357-base pair mitochondrial control region locus sequenced for 103 individuals and 18 nuclear microsatellite loci genotyped for 245 individuals to investigate population structure in the Atlantic and Pacific populations of the pelagic seabird, Leach's storm-petrel Oceanodroma leucorhoa leucorhoa. This species is under intense predation pressure at one regionally important colony on St Kilda, Scotland, where a disparity between population decline and predation rates hints at immigration from other large colonies. AMOVA, F(ST), Φ(ST) and Bayesian cluster analyses revealed no genetic structure among Atlantic colonies (Global Φ(ST) = -0.02 P > 0.05, Global F(ST) = 0.003, P > 0.05, STRUCTURE K = 1), consistent with either contemporary gene flow or strong historical association within the ocean basin. The Pacific and Atlantic populations are genetically distinct (Global Φ(ST) = 0.32 P < 0.0001, Global F(ST) = 0.04, P < 0.0001, STRUCTURE K = 2), but evidence for interocean exchange was found with individual exclusion/assignment and population coalescent analyses. These findings highlight the importance of conserving multiple colonies at a number of different sites and suggest that management of this seabird may be best viewed at an oceanic scale. Moreover, our study provides an illustration of how long-distance movement may ameliorate the potentially deleterious impacts of localized environmental change, although direct measures of dispersal are still required to better understand this process.

The comparative biology of diving in two genera of European Dytiscidae (Coleoptera).

Surfacing behaviour is fundamental in the ecology of aquatic air-breathing organisms; however, it is only in vertebrates that the evolutionary ecology of diving has been well characterized. Here, we explore the diving behaviour of dytiscid beetles, a key group of surface-exchanging freshwater invertebrates, by comparing the dive responses of 25 taxa (Deronectes and Ilybius spp.) acclimated at two temperatures. The allometric slopes of dive responses in these dytiscids appear similar to those of vertebrate ectotherms, supporting the notion that metabolic mode shapes the evolution of diving performance. In both genera, beetles spend more time submerged than on the surface, and surface time does not vary with the temperature of acclimation. However, presumably in order to meet increased oxygen demand at higher temperatures, Deronectes species increase surfacing frequency, whereas Ilybius species decrease dive time, an example of 'multiple solutions.' Finally, widespread northern species appear to possess higher diving performances than their geographically restricted southern relatives, something which may have contributed to their range expansion ability.

Haemoptysis: diagnosis and treatment.

Haemoptysis is a common symptom in clinical practice, which requires further investigation. Fortunately, massive haemoptysis only accounts for a small proportion of these episodes. It is a medical emergency that carries a high mortality rate. There are no agreed management guidelines. This review discusses proposed methods of resuscitation as well as outlining a diagnostic algorithm and discusses treatments including bronchial artery embolization, endobronchial therapy, surgery and medical therapies.

Inhaled dry powder mannitol in cystic fibrosis: an efficacy and safety study.

This international phase III study of inhaled dry powder mannitol was a randomised, double-blind, 26-week study, followed by a further 26-week, open-label (OL) extension. 324 cystic fibrosis (CF) patients were randomised, in a 3:2 ratio, to mannitol (400 mg b.i.d.) and control groups. The primary efficacy end-point was to determine the change in forced expiratory volume in 1 s (FEV1) over the double-blind phase. Secondary end-points included changes in forced vital capacity and pulmonary exacerbations. A significant improvement in FEV1 was seen over 26 weeks (p<0.001) and was apparent by 6 weeks, irrespective of concomitant recombinant human deoxyribonuclease (rhDNase) use. At 26 weeks, there was a significant improvement in FEV1 of 92.9 mL for subjects receiving mannitol compared with controls (change from baseline 118.9 mL (6.5%) versus 26.0 mL (2.4%); p<0.001). Improvements in FEV1 were maintained up to 52 weeks in the OL part of the study. There was a 35.4% reduction in the incidence of having an exacerbation on mannitol (p=0.045). The incidence of adverse events (AEs) was similar in both groups, although treatment-related AEs were higher in the mannitol compared with the control group. The most common mannitol-related AEs were cough, haemoptysis and pharyngolaryngeal pain. Mannitol showed sustained, clinically meaningful benefit in airway function in CF, irrespective of concomitant rhDNase use. Mannitol appears to have an acceptable safety profile for patients with CF.

Adult cystic fibrosis care in the 21st century.

Cystic fibrosis (CF) is the most common autosomal recessive inherited disease of Caucasian populations. As a result of a variety of diagnostic and therapeutic strategies there has been a dramatic increase in the life expectancy of patients with CF in the last decades and 50% of patients are now adults. This review will focus on the disease in adults and the provision of appropriate care. The complex care required to improve the survival and quality of life in the adult patients can best be provided in a dedicated adult cystic fibrosis unit. These units currently exist in many European countries, but more are needed in Italy.

British Thoracic Society guideline for non-CF bronchiectasis.

The diagnosis, investigation and particularly management of bronchiectasis has been largely empirical and the subject of relatively few controlled clinical trials. There are no clear guidelines, although an Australian position statement has been published concerning bronchiectasis in children. The purposes of these guidelines were therefore threefold: (1) to identify relevant studies in non-cystic fibrosis (CF) bronchiectasis; (2) to provide guidelines on management based on published studies where possible or a consensus view; and (3) to identify gaps in our knowledge and identify areas for future study.

Cystic fibrosis neutrophils have normal intrinsic reactive oxygen species generation.

Previous studies have identified abnormalities in the oxidative responses of the neutrophil in cystic fibrosis (CF), but it is unclear whether such changes relate to loss of membrane cystic fibrosis transmembrane conductance regulator (CFTR) or to the inflammatory environment present in this disease. The aim of the present study was to determine whether neutrophils from CF patients demonstrate an intrinsic abnormality of the respiratory burst. The respiratory burst activity of neutrophils isolated from stable DeltaF508 homozygote CF patients and matched healthy controls was quantified by both chemiluminscence and cytochrome C reduction. Expression of NADPH oxidase components and CFTR was determined by Western blotting and RT-PCR. The oxidative output from neutrophils from CF in response to receptor-linked and particulate stimuli did not differ from that of controls. Expression of NADPH oxidase components was identical in CF and non-CF neutrophils. While low levels of CFTR mRNA could be identified in the normal human neutrophil, we were unable to detect CFTR protein in human neutrophil lysates or immunoprecipitates. CFTR has no role in controlling neutrophil oxidative activity; previously reported differences in neutrophil function between CF and non-CF subjects most likely relate to the inflammatory milieu from which the cells were isolated.