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1.
Capsule: The occurrence of high numbers of ectoparasites in nests of Common Eiders may be related to nest densities and nesting behaviour.

Aims: To estimate abundances of ectoparasites and occurrence of blood-covered eggs, and relate those to nest bowl ages, nest bottom material and the incubation stages of eggs, in nests at two different Common Eider colonies.

Methods: Nests were collected at Hvallátur and Rif, two sites at Breiðafjörður, West Iceland, in June and July 2012. The nest bottom material was classified to vegetation species and invertebrates were identified to species when possible.

Results: The flea Ceratophyllus garei was the dominant ectoparasite at both sites, with median abundances higher at Hvallátur than at Rif in June. In July, the mean abundance of fleas was higher than observed in June at Rif. There were positive relationships between the flea abundances and the incubation stages of the nests, the blood cover of the eggs and the type of nesting material. No relationship was observed between the age of nesting bowls and adult flea abundances.

Conclusion: Disadvantages of large parasite loads on the later nesters (second clutch in each nest) at Rif may be compensated by shared nest attendance and the concurrent added time for preening for females while other females attend their nests.  相似文献   


2.
Capsule: Northern Lapwing Vanellus vanellus avoid nesting close to small woodland patches but nest predation rates do not vary with distance to woodland patches, either because risky areas are avoided or perceived nest predation risk does not reflect actual risk.

Aims: To explore the effects of woodland patches in wet grassland landscapes on nest distribution and success of Lapwings.

Methods: We quantified the effect of woodland patches on the distribution and outcome of Lapwing nests across four wet grassland sites by mapping nest distribution and monitoring nest outcomes.

Results: Lapwing nested significantly further from woods than expected by chance. Neither nest predation rates nor the probability of predation occurring at night (thus primarily mammalian predators) or day (primarily avian predators) varied in relation to distance from woodland patches.

Conclusions: High levels of nest and chick predation in wet grassland landscapes limit the capacity for breeding wader populations to be self-sustaining. Consequently, identifying manageable landscape features that influence predation rates is an important focus of conservation research. Lapwing avoid breeding close to woodland but, as nest predation rates do not vary with distance from woodland patches, their removal may increase the area of suitable nesting habitat but is unlikely to substantially influence productivity.  相似文献   


3.
Capsule: Hen Harriers Circus cyaneus on the Isle of Mull, UK, are associated with habitat mosaics consisting of moorland, scrub and forestry but avoid grazed land, suggesting that forested habitats could be managed sympathetically for the Hen Harrier in the future should the current UK population increase.

Aims: To use distribution modelling to investigate nesting habitat associations using a long-term data set for the Hen Harrier on Mull.

Methods: We develop area-interaction models using a least absolute shrinkage and selection operator penalty to explore the distribution of 102 Hen Harrier nest sites in relation to habitat and topography. Our model is then successfully validated in tests using data for 70 nest sites from subsequent years.

Results: Our model is effective in predicting suitable areas for Hen Harrier nest sites and indicates that Hen Harriers on Mull are found in habitat mosaics below 200 m above sea level. Hen Harrier nest intensity is positively associated with increasing proportions of moorland and scrub, open canopy forestry and closed canopy forestry. Nest intensity is negatively associated with increasing proportions of grazed land.

Conclusion: Hen Harriers avoid grazed areas but are relatively tolerant of other habitat combinations. These findings are supported by previous observations of Hen Harrier habitat use and have implications for the recovery of some Hen Harrier populations in Special Protection Areas and future forest management. Open canopy forest and forest mosaics could potentially be incorporated into landscape-scale conservation plans for Hen Harriers using the population on Mull as an example.  相似文献   


4.
Context: Apoptotic dysregulation plays a role in the pathogenesis of polycystic ovary syndrome (PCOS).

Objective: To evaluate circulatory apoptotic markers and oxidative stress in patients with PCOS.

Materials and methods: Forty-four women with PCOS, and 44 healthy women as controls were enrolled in the study. Oxidative stress parameters and caspases levels were measured in serum.

Results: The caspase 9 level was significantly lower and related with oxidant status in patients with PCOS, while the circulating levels of caspases 3 and 7 were statistically similar in both groups.

Discussion: This study is the first report demonstrating the circulating levels of apoptotic markers and their relationship with oxidant status in PCOS.

Conclusion: The circulating caspase 9 and oxidant status might contribute to apoptotic dysregulation in PCOS.  相似文献   


5.
Capsule: Predation rates of artificial nests along elevational gradients were higher closer to the treeline in the European Alps.

Aims: Alpine grassland birds tend to show an avoidance of mature trees, possibly due to an edge effect, such as higher predation pressure close to the treeline. This study aimed to estimate potential predation pressure in relation to the distance from the treeline and other environmental variables by using artificial nests positioned along elevational transects in the Italian Alps.

Methods: A total of 119 artificial nests were positioned and monitored during the breeding season. For each nest, habitat data at small and large scales were collected. Daily nest survival was estimated using MARK.

Results: The most informative model included date, distance from the treeline and a micro-habitat structure variable. In particular, the model showed a positive relationship between nest survival and the distance from the treeline.

Conclusions: This study suggests that if treelines advance due to climate change, the functional habitat loss may be greater than physical habitat loss, since the optimal breeding area would be further away from the forest edge. The conservation of high-elevation grasslands in relation to environmental changes may therefore be addressed through management strategies to maintain open habitats.  相似文献   


6.
Context: Drug-induced phospholipidosis is one of the significant concerns in drug development, especially in safety assessment and noninvasive diagnostic tool is highly desirable.

Objective: The objective of this study is to explored novel biomarkers for phospholipidosis using a metabolomic approach.

Method: NMR spectrometry and LC/MS/MS analyses were applied to urine and plasma of rats administrated cationic amphiphilic drugs.

Results: The phenylacetylglycine to hippuric acid ratio in plasma was increased in time and dose-dependent manners; and it was well correlated with histopathological observation.

Conclusion: The plasma phenylacetylglycine to hippuric acid ratio is a potential marker in monitoring drug-induced phospholipidosis.  相似文献   


7.
Context: Von Hippel–Lindau disease (VHLD) is a rare inherited neoplastic syndrome. Among all the VHLD-associated tumors, clear cell renal cell carcinoma (ccRCC) is the major cause of death.

Objective: The aim of this paper is the discovery of new non-invasive biomarker for the monitoring of VHLD patients.

Materials and methods: We compared the urinary proteome of VHLD patients, ccRCC patients and healthy volunteers.

Results: Among all differentially expressed proteins, alpha-1-antitrypsin (A1AT) and APOH (beta-2-glycoprotein-1) are strongly over-abundant only in the urine of VHLD patients with a history of ccRCC.

Discussion and conclusion: A1AT and APOH could be promising non-invasive biomarkers.  相似文献   


8.
Context: Troponin T upstream open reading frame peptide (TnTuORF) may be useful as a novel biomarker in acute cardiac syndromes.

Objective: The study examined the early release kinetics of TnTuORF.

Materials and methods: We analyzed the time course of the release of cardiac troponins I and T and TnTuORF in patients (n?=?31) with hypertrophic obstructive cardiomyopathy undergoing transcoronary ablation of septal hypertrophy (TASH).

Results: Fifteen minutes after TASH, the levels of both troponins increased significantly (cTnT median: 18?ng/L versus 27?ng/L; cTnI median: 15?ng/L versus 25?ng/L). TnTuORF showed no variation.

Discussion: We observed a significantly greater increase in cTnI compared with cTnT.

Conclusion: Our results demonstrate that troponin assays allow early detection of myocardial injury, whereas TnTuORF levels remain unchanged in this setting.  相似文献   


9.
Capsule: Barn swallows Hirundo rustica using artificial nest cups had greater reproductive success than those building and using natural nests.

Aims: To quantify reproductive success of Barn Swallows breeding in artificial man-made nests and compare with those using natural nests.

Methods: In 2012–16, the breeding attempts of 231 pairs of Barn Swallows were monitored in artificial and natural nests in an urban habitat in Denmark.

Results: Pairs breeding in old natural nests and artificial nests bred earlier, laid more eggs, and produced more nestlings and fledglings than pairs breeding in new natural nests. Inter-clutch intervals were shorter in Barn Swallow pairs using artificial nests and old natural nests. Nest cup volume and nest volume of newly built nests were significantly larger and more variable than artificial nests excluding an effect of nest size as an explanation for the larger clutches laid in artificial nests. Increased energy and time costs of nest construction may have reduced reproductive success for pairs building natural nests.

Conclusion: Artificial nests were readily accepted by Barn Swallows, they had a similar low predation rate as natural nests, and they proved to be a possible conservation option for this declining passerine breeding in urban habitats as evidenced by their 75% higher reproductive success in artificial nests.  相似文献   


10.
Context: Urine lactate may be a novel biomarker of lactate production capacity but its reliability has been unsatisfactory so far.

Objective: To compare the reliability of urine lactate between controlled hydration and no hydration after maximal exercise.

Material and methods: Athletes performed swimming exercise four times: two followed by consumption of 1?L of water and two followed by no water intake. Blood and urine lactate was measured.

Results: The reliability of urine lactate was good and similar to that in blood only after controlled hydration. Blood and urine lactate were correlated under both hydration conditions.

Discussion and conclusion: Controlled hydration after exercise provides satisfactory reliability of urine lactate.  相似文献   


11.
Context: The mechanism of nickel-induced pathogenesis remains elusive.

Objective: To examine effects of nickel exposure on plasma oxidative and anti-oxidative biomarkers.

Materials and methods: Biomarker data were collected from 154 workers with various levels of nickel exposure and from 73 controls. Correlations between nickel exposure and oxidative and anti-oxidative biomarkers were determined using linear regression models.

Results: Workers with a exposure to high nickel levels had significantly lower levels of anti-oxidants (glutathione and catalase) than those with a lower exposure to nickel; however, only glutathione showed an independent association after multivariable adjustment.

Discussion and conclusion: Exposure to high levels of nickel may reduce serum anti-oxidative capacity.  相似文献   


12.
Context: Clinical study of breast cancer patients in Chicago, IL, USA.

Objective: Ascertain the utility of measurements of single-strand breaks (SSB) in DNA for assessment of breast cancer risk.

Methods: Fine-needle aspirates of the breast, SSB by nick translation, percent breast density (PBD), Gail model risk, cumulative methylation index (CMI), enzymes of DNA repair and tissue antioxidants.

Results: DNA repair enzymes and 4-hydroxyestradiol were negatively associated with SSB; CMI and PBD were positively associated.

Conclusions: Quantitative measurement of SSBs by this procedure indicates the relative number of SSBs and is related to promoter methylation, antioxidant availability and percent breast density.  相似文献   


13.
Context: Colorectal cancer is one of the most common cancers worldwide. Epigenetic alterations play an important role in the pathogenesis of the colorectal cancer.

Objective: This review has focused on the most recent investigations, which has suggested potential epigenetic biomarkers in colorectal cancer.

Methods: Evidences were achieved by searching online medical databases including Google scholar, Pubmed, Scopus and Science Direct.

Results: Extensive studies have indicated that aberrant epigenetic modifications could serve as potential biomarkers for diagnosis, prognosis and prediction of colorectal cancer.

Conclusion: Advances in aberrant epigenetic modifications can open new avenues for exploration of reliable and robust biomarkers to improve the management of CRC patients.  相似文献   


14.
Context: About 50–70% of patients with non-muscle invasive bladder cancer (NMIBC) experience relapse of disease.

Objective: To establish a panel of protein biomarkers incorporated in a multiplexed microarray (BCa chip) and a classifier for diagnosing recurrent NMIBC.

Materials and methods: Urine samples from 45 patients were tested. Diagnostic performance was evaluated by receiver operating characteristic (ROC) analysis.

Results: A multi biomarker panel (ECadh, IL8, MMP9, EN2, VEGF, past recurrences, BCG therapies and stage at diagnosis) was identified yielding an area under the curve of 0.96.

Discussion and conclusion: This biomarker panel represents a potential diagnostic tool for noninvasive diagnosis of recurrent NMIBC.  相似文献   


15.
Capsule: Playback is effective at improving detectability of Little Owls.

Aims: To trial a playback survey methodology for Little Owls in the UK to determine detectability and practicalities which could inform potential future national monitoring efforts.

Methods: Nocturnal playback surveys were carried out in an open landscape in the east of England in spring 2015. Twelve 2?×?2?km survey squares were each visited four times. Little Owl calls were broadcast from three locations within each square along a linear transect and spaced 500 m apart. The responses of owls of any species were recorded. Little Owl occupancy was later confirmed through existing nest monitoring efforts.

Results: Little Owls were detected responding to playback in all survey squares and were confirmed to be breeding in 8 of the 12. Detection and response rates were greater when combining data from multiple broadcast locations. The likelihood of Little Owls responding decreased with greater distance of broadcast location to known nest site, but no relationships were identified with time of evening or the presence of other owl species.

Conclusion: Playback methodology proved to be effective at increasing detectability of Little Owls and this study provides an estimated response rate to inform future efforts.  相似文献   


16.
Kevin B. Briggs 《Bird Study》2016,63(4):516-524
Capsule: Pied Flycatchers Ficedula hypoleuca use different materials to construct their nests according to local availability and geographical location.

Aims: This study tested the hypotheses that Pied Flycatcher nests were constructed from the leaves of different tree species in proportion to their occurrence within the breeding territories and that nest composition varied between geographical locations.

Methods: In Lancashire, Pied Flycatcher nests were collected from nestboxes built in locations dominated by different tree species and were deconstructed to determine which materials were used.

Results: The leaves found in nests generally reflected their availability within the locality of the territories rather than showing evidence of selective use of some leaf species. However, the use of moss was dominated by the use of one species in all but two nests. Nests from Lancashire were significantly different in composition when compared with published data for nests from north Wales and central Spain.

Conclusion: Pied Flycatchers exhibit plasticity in nest construction behaviour because they were opportunistic in their choice of most leaves as nesting materials, although they may be selective in their choice of moss.  相似文献   


17.
Purpose: To evaluate the effectiveness of 8-week low-frequency plantar vibration training on patients with sensorimotor diabetic peripheral neuropathy (DPN).

Participants: Twelve patients took part in the investigation.

Results: An increase of the nerve conductive velocity of soral and peroneal nerves of feet, increased postural stability, and disappearance of the pain and tingling were observed.

Conclusion: The obtained results provide evidence for beneficial effects of 8-week plantar vibration training in patients with DPN.  相似文献   


18.
Context: Quantitative changes of salivary proteins due to acute stress were detected.

Objective: To explore protein markers of stress in saliva of eight medical residents who performed emergency medicine simulations.

Materials and methods: Saliva was collected before the simulations, after the simulations, and following morning upon waking. Proteins were separated by sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE), identified by mass spectrometry (MS), and relatively quantified by densitometry.

Results: Salivary alpha-amylase and S–type cystatins significantly increased, while the ~26?kDa and low-molecular weight (MW) (<10?kDa) SDS-PAGE bands exhibited changes after stress.

Discussion and conclusion: Alpha-amylase and cystatins are potential salivary markers of acute stress, but further validation should be performed using larger sample populations.  相似文献   


19.
Capsule: Supplementary feeding stations provide a useful conservation benefit for vultures, without disrupting their natural movement ecology.

Aims: To understand the effects of providing supplementary food on the movement ecology of vultures.

Methods: We used Global Positioning System tracking devices to monitor the movements of 28 Cape Vultures Gyps coprotheres using feeding stations in South Africa. We calculated home range values and then performed a habitat selection analysis.

Results: We show that aside from roost sites, vulture feeding stations are the most important environmental variable that explains vulture movements. However, we found that the birds ranged over areas without supplementary food and their mean home range values were comparable to those measured before the inception of feeding stations.

Conclusion: Our findings suggest that the use of supplementary feeding sites did not significantly impact on the natural foraging behaviour of the species.  相似文献   


20.
Context: Several urinary PAHs metabolites can be detected by HPLC-MS/MS for individual exposure assessment.

Objective: Quantitation of urinary metabolites of four PAHs, selected on the basis of their significance, with reduced costs and high sensitivity.

Materials and methods: HPLC-MS/MS was used and pure standards and isotope-labeled internal analogs of the analytes. Two hundred samples were tested after enzymatic hydrolysis.

Results: Accuracy was higher than 90% and variability lower than 19%; LODs permit to measure 1-hydroxypyrene, 1 and 2-hydroxynaphthalene in all subjects, 6-hydroxynitropyrene in the 65% and 3-hydroxybenzo[a]pyrene in the 70%.

Discussion and conclusion: The method is suitable both for occupational and for environmental studies. This is the first paper reporting urinary levels of 6-hydroxynitropyrene in European subjects, nonoccupationally exposed to nitro-PAHs.  相似文献   


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