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1.
Capsule: In Black-browed Albatrosses Thalassarche melanophris nutritional condition is correlated between parents and their offspring.

Aims: To test resource allocation hypotheses analysing the relationship between parental and offspring nutritional condition.

Methods: We measured blood chemistry parameters related with nutritional condition in 24 parents and their nestlings in a colony of Black-browed Albatrosses.

Results: There were no significant differences in blood parameters between sexes or location of the nest within the colony, neither among adults nor among nestlings. We found a significant positive correlation between parents and the nutritional condition of their offspring, measured as urea, uric acid and beta-hydroxybutyrate concentrations in blood.

Discussion: These relationships demonstrate that condition of the young seems to be merely a reflection of parental condition. An interesting relationship between alkaline phosphatase concentration in adults and nutritional condition of their nestlings was found, suggesting that age of the parents would be a key factor explaining quality of the nestling.  相似文献   


2.
Capsule Evidence from two tern species does not support the theory that species in expansion should bias their brood sex ratios towards the more dispersing sex.

Aims Sex ratio theory predicts that when a species is in expansion, the sex ratio should be biased towards the more dispersing sex. We compared the sex ratio of nestlings in two closely related species of terns, characterized by different expansion rates: the White-winged Tern Chlidonias leucopterus (an expansive species) and the Black Tern Chlidonias niger (a non-expansive species).

Methods The fieldwork was carried out in the valleys of the Rivers Bug and Narew in east-central Poland, from 2008 to 2014, during which time eight White-winged Tern colonies and ten Black Tern colonies were monitored. Nest inspections began around 15–20 May, when the first eggs were laid, and continued until mid-July, when the last nestlings were 7–20 days old.

Results The nestling sex ratios were similar in both species, and the differences between number of females and males were not significant (White-winged Tern: 56.6% females vs. 43.4% males; Black Tern: 57.4% females vs. 42.6% males).

Conclusions The lack of differences in nestling sex ratio in these species may be due to the cessation of the White-winged Tern's expansion in this area or because the sex ratio is characteristic of Sternidae species, as similar results have been reported for other tern species.  相似文献   


3.
Capsule: Nestling Southern Grey Shrikes Lanius meridionalis show a high prevalence of haemosporidian parasites including five lineages described here for the first time.

Aims: To examine the prevalence of various haemosporidian lineages in nestlings of three separated Iberian populations of the Southern Grey Shrike.

Methods: Blood samples were taken from nestling Southern Grey Shrikes from three agroecosystem areas in the Iberian Peninsula. Parasites were detected from blood samples using polymerase chain reaction screening.

Resusts: Nestlings were parasitized by 11 different lineages belonging to the genera Haemoproteus (3.8%), Plasmodium (0.5%) and Leucocytozoon (1.8%), including five new undescribed lineages. These are among the highest prevalence levels of haemosporidians parasites (7.4%) for nestlings of passerine birds.

Conclusion: Our findings suggest that the distribution of avian haemosporidians is determined by complex effects including climate and biogeography. Most parasite lineages were not universally spread across shrike populations, despite being otherwise widespread both geographically and taxonomically.  相似文献   


4.
Capsule: Growth trajectories of Blue Tit Cyanistes caeruleus nestlings differed between sexes and were negatively affected by rain but not by temperature during the linear growth phase (LGP).

Aims: To model the growth trajectories of Blue Tit nestlings and to identify the main ecological factors affecting them.

Methods: Sixty-five nestling Blue Tits from a population in northern Italy were weighed at regular intervals and sexed using molecular genetic techniques. The LGP period was identified and analysed to test for the influence of age, sex, hatching date, brood size, temperature and rainfall on individual daily growth rates during the LGP.

Results: Growth curves showed no pre-fledging mass loss. Body mass differed between the sexes, with males being 5% heavier than females at the pre-fledging stage. Daily growth rates during the LGP were higher for males and on non-rainy days, while they were not affected by other factors.

Conclusion: The higher daily growth rate observed in males during the LGP may determine the extent of sexual size dimorphism at the pre-fledging stage. Susceptibility of growth trajectories to environmental conditions was limited to rainfall and was similar in the two sexes. This contrasts with findings from previous studies, which found sex-biased environmental sensitivity of Blue Tit nestlings.  相似文献   


5.
Capsule: Local weather conditions, but not a city-associated diet composition, influence the breeding performance of urban Eurasian Kestrels Falco tinnunculus.

Aims: We aim to explore the impact of diet composition, specifically a high proportion of avian prey, on the breeding performance of urban Eurasian Kestrels under different weather conditions.

Methods: The Eurasian Kestrel is known to exploit cities and occurs in the study area of Vienna, Austria (415?km2) at high breeding densities of 89–122 pairs/100?km2. Unlike their rural conspecifics which specialize in voles, urban Kestrels are generalists, preying on passerines and mammals, but also reptiles and insects. We explore this alternative diet through pellet analyses along an urbanization gradient over a 5-year period and link diet to reproductive performance, taking local weather conditions into account.

Results: Our results showed that weather had a greater influence on breeding performance than did diet. Warm and dry weather during the arrival and courtship period was correlated with earlier egg-laying, higher nestling survival and an overall higher breeding success. Dry winters increased the proportion of mammalian prey, whereas low temperatures and high rainfall during the nestling phase increased the proportion of avian prey. Overall, a more diverse diet was also associated with higher rainfall, but only during the arrival and courtship period.

Conclusion: Our research shows a stronger connection between breeding performance and weather conditions than between breeding performance and diet composition, although there may be indirect effects of weather on prey availability which augment the impact of diet on reproductive output in the Eurasian Kestrel.  相似文献   


6.
Capsule: Morphologically similar sympatrically breeding species differ in diet and foraging strategies, which could explain interspecific variation in breeding success and reproductive output.

Aims: To compare provisioning rate and diet of nestling Arctic (Sterna paradisaea) and Common Terns (Sterna hirundo), and examine how variation in provisioning behaviour influences reproductive parameters.

Methods: Arctic and Common Tern nests were observed from June to July 2011 on Coquet Island, northeast England. We compared chick provisioning rate, diet and energy delivery rate between species, and examined whether these parameters were associated with interspecific differences in chick growth and survival, and total number of chicks fledged.

Results: Arctic Terns delivered higher percentages of smaller Sandeels (Ammodytes marinus) and juvenile fish to chicks than did Common Terns, which delivered comparatively high percentages of larger Sprats (Sprattus sprattus). Although chick growth rate and survival were not significantly different between species, Common Terns fledged more chicks than Arctic Terns due to a tendency for larger clutch sizes.

Conclusion: Our study suggests that interspecific differences in diet and foraging strategies can support total reproductive output in morphologically similar species.  相似文献   


7.
Capsule: Carolina Wrens Thryothorus ludovicianus in urban and rural environments responded most intensely to predators common to their environments.

Aims: To determine the role of experience in predator recognition and response among Carolina Wrens. We predicted that wrens in the urban environment, where domestic cats are common, would respond more intensely to mounts of cats than snakes (a less common nest predator) placed near their nests. In the rural (forested) environment, we predicted a greater response to snakes than cats, because snakes are the more common predator in that environment.

Methods: We placed mounted specimens of a snake and a cat near wren nests at the late nestling stage and quantified responses. We used a Rock Dove Columba livia mount as the control because it is a non-threatening species to the nestlings, and should be familiar to the wrens.

Results: Carolina Wrens in the urban area responded most intensively to the cat mounts, whereas those in the rural environment responded more to the snake, with indications of innate predator recognition and defence. Cats were more common in the urban environment. Wrens used different alarm calls in the two habitats, but further study is needed to understand the significance of this variation.

Conclusions: Birds may have the ability to adapt their responses to local predators, both native and non-native, which may be especially important for their success in urbanized habitats.  相似文献   


8.
Capsule: The diet of Black Guillemot Cepphus grylle grylle chicks in the Baltic Sea region was dominated by Viviparous Eelpout Zoarces viviparus. Risk of nest predation by avian and mammalian predators was perceived to be low, and hatching and fledging success were high.

Aims: To gain insight into the ecology of nestling Black Guillemots in the Baltic Sea region to fill knowledge gaps and benefit its conservation.

Methods: Two island groups in the Baltic Sea were visited several times during the breeding season of 2014 and 2015 to monitor nestling survival and fledging. In addition, camera traps were used in 2014 to monitor prey brought to chicks by adults and record possible nest predation events.

Results: Hatching success was 0.89 and 0.73 in 2014 and 2015, respectively, and fledging success was very high (0.95 and 0.97). No incidences of avian or mammalian predation were observed. Chicks fledged at night between 32 and 38 days after hatching. Viviparous Eelpout made up 95% of the prey items brought to the chicks by adults.

Conclusions: The hatching rate and fledging rate of the Black Guillemot was high in our study region. Juveniles seemed highly dependent on the availability of eelpout. Changes in the abundance of this species may therefore have negative effects on chick survival.  相似文献   


9.
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   


10.
Context: Carboxymethyl-lysine (CML) results from oxidative stress and has been linked to cardiovascular disease.

Objective: The objective of this study is to investigate the association between sleep-disordered breathing (SDB) – a source of oxidative stress – and CML.

Materials and methods: About 1002 participants in the Cardiovascular Health Study (CHS) were studied.

Results: Women with SDB had significantly higher CML concentration compared with those without SDB (OR?=?1.63, 95%CI?=?1.03–2.58, p?=?0.04). The association was not significant among men.

Discussion: SDB was associated with CML concentration among elderly women but not men in the Cardiovascular Health Study.

Conclusion: Accumulation of CML may be an adverse health consequence of SDB  相似文献   


11.
Capsule: The diet of the Montagu’s Harrier Circus pygargus is variable and comprises the most available prey at a given time of the season. We found no evidence for a relationship between diet and land-use in the core foraging zone.

Aims: We investigated whether the diet of the Montagu’s Harrier reflects the available prey and how it changes across the breeding season and in relation to land-use.

Methods: We analysed pellets collected at nests between 2007 and 2011. We looked for nonlinear patterns in the occurrence of prey categories in the pellets as a nonlinear function of the Julian date. Moreover, we tested whether the diet is affected by land-use within a radius of 2299 m from the nest.

Results: Four thousand four hundred and sixty-five prey items were found in 880 pellets and 76 prey remains collected at 63 sites. The diet did not depend on the land-use structure but showed a significant temporal variation.

Conclusions: The diet of the Montagu’s Harrier follows the availability of the prey in the foraging habitat. We conclude that the type of land-use in the vicinity of the nesting habitat has a rather weak effect on the diet of the Montagu’s Harrier.  相似文献   


12.
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   


13.
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   


14.
Context: Association between inherited variants and the risks of sepsis is controversial.

Objective: To evaluate the risk of pneumonia-induced sepsis by examining its linkage with polymorphisms of IL-6 and IL-10.

Materials and methods: Samples were obtained from 188 pneumonia-induced sepsis patients, 162 pneumonia patients and 200 healthy controls.

Results: Subjects with IL-10 -1082 AA genotypes and IL-6 -174?CC genotype had a higher risk of sepsis and increased mRNA levels.

Conclusion: The variants of IL-10 -1082 A allele and IL-6 -174 C allele contributed to an increased risk of pneumonia-induced sepsis.  相似文献   


15.
Context: Inflammation is one of the mechanisms underlying cardiac syndrome X (CSX).

Objectives: Few studies have compared the expression of inflammatory or adhesion molecules between coronary artery disease (CAD) versus CSX.

Materials and methods: Ninety-two CSX and 145 CAD subjects without known diabetes mellitus underwent coronary angiogram for angina.

Results: Vascular cell adhesion molecule (VCAM)-1 (median, 507 versus 431?ng/ml, p?=?0.001) was significantly higher in the CAD group. In the binary regression, VCAM-1 was a significant differential factor for CAD versus CSX.

Discussion and conclusion: Adhesion molecules might be implicated in the differential expression of macro versus microvascular coronary disease.

Trial registration number: NCT01198730 at https://clinicaltrials.gov  相似文献   


16.
Context: Soluble CD40 ligand (sCD40l) can predict cardiovascular events (CVE) and mortality in haemodialysis (HD) patients (short-, medium-term follow-up studies).

Objective: To evaluate the relationship between sCD40l and survival, CVE and mortality in HD patients on long-term follow-up.

Methods: We registered 46?HD patients’ baseline characteristics, mortality and CVE for 108 months.

Results: SCD40l correlated positively with C-reactive protein, was higher in survivors, but had no impact on survival and was not predictive for CVE or CV mortality.

Conclusion: The levels of sCD40l have no influence on survival or CVE and mortality in HD patients in a long-term follow-up.  相似文献   


17.
Context: The endothelin system (Big-ET-1) is a key regulator in cardiovascular (CV) disease and congestive heart failure (CHF).

Objectives: We have examined the incremental value of Big-ET-1 in predicting total and CV mortality next to the well-established CV risk marker N-Terminal Pro-B-Type Natriuretic Peptide (NT-proBNP).

Methods: Big-ET-1 and NT-proBNP were determined in 2829 participants referred for coronary angiography (follow-up 9.9 years).

Results: Big-ET-1 is an independent predictor of total, CV mortality and death due to CHF.

Discussion: The conjunct use of Big-ET-1 and NT-proBNP improves the risk stratification of patients with intermediate to high risk of CV death and CHF.

Conclusions: Big-ET-1improves risk stratification in patients referred for coronary angiography.  相似文献   


18.
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   


19.
Context: Genetics play a major role in development and pathophysiology of Type 2 diabetes mellitus (T2DM).

Objective: To asses the association of Guanine nucleotide-binding protein (GNB3) (C825T) gene's polymorphism with T2DM.

Materials and methods: A case–control study including 400 North Indians was performed using Polymerase Chain Reaction–Restriction Fragment Length Polymorphism (PCR-RFLP) approach to analyze genetic polymorphism.

Results: No significant difference was observed in genotype and allele frequencies of GNB3 gene on comparing cases with controls.

Discussion: Our study is in agreement with studies on Polish, Japanese, Hispanic-American and Danish populations who observed no significant association between GNB3 (C825T) polymorphism and T2DM.

Conclusion: GNB3 (C825T) polymorphism is not associated with T2DM.  相似文献   


20.
Capsule: Pre-fledging survival in a Yellow-legged Gull Larus michahellis population in northern Iberia is negatively correlated to hatching date.

Aims: To explore which factors have more importance in determining the pre-fledging daily survival rates in a Yellow-legged Gull population from northern Iberia. Specifically, we tested for the effect of hatching date and order, body size and condition and meteorological conditions on pre-fledging survival.

Methods: Cormack–Jolly–Seber models with mixtures were used to model daily survival rates.

Results: Daily survival rates were mostly negatively affected by hatching date.

Conclusions: Hatching date was the most important factor affecting survival of chicks during the pre-fledging period in a Yellow-legged Gull colony from northern Iberia.  相似文献   


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