| 1. |
- Elliott, Kyle H., et al.
(författare)
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Age-related variation in energy expenditure in a long-lived bird within the envelope of an energy ceiling
- 2014
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Ingår i: Journal of Animal Ecology. - : Wiley. - 0021-8790 .- 1365-2656. ; 83:1, s. 136-146
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Tidskriftsartikel (refereegranskat)abstract
- Energy expenditure in wild animals can be limited (i) intrinsically by physiological processes that constrain an animal's capacity to use energy, (ii) extrinsically by energy availability in the environment and/or (iii) strategically based on trade-offs between elevated metabolism and survival. Although these factors apply to all individuals within a population, some individuals expend more or less energy than other individuals. To examine the role of an energy ceiling in a species with a high and individually repeatable metabolic rate, we compared energy expenditure of thick-billed murres (Uria lomvia) with and without handicaps during a period of peak energy demand (chick-rearing, N=16). We also compared energy expenditure of unencumbered birds (N=260) across 8years exhibiting contrasting environmental conditions and correlated energy expenditure with fitness (reproductive success and survival). Murres experienced an energy ceiling mediated through behavioural adjustments. Handicapped birds decreased time spent flying/diving and chick-provisioning rates such that overall daily energy expenditure remained unchanged across the two treatments. The energy ceiling did not reflect energy availability or trade-offs with fitness, as energy expenditure was similar across contrasting foraging conditions and was not associated with reduced survival or increased reproductive success. We found partial support for the trade-off hypothesis as older murres, where prospects for future reproduction would be relatively limited, did overcome an energy ceiling to invest more in offspring following handicapping by reducing their own energy reserves. The ceiling therefore appeared to operate at the level of intake (i.e. digestion) rather than expenditure (i.e. thermal constraint, oxidative stress). A meta-analysis comparing responses of breeding animals to handicapping suggests that our results are typical: animals either reduced investment in themselves or in their offspring to remain below an energy ceiling. Across species, whether a handicapped individual invested in its own energy stores or its offspring's growth was not explained by life history (future vs. current reproductive potential). Many breeding animals apparently experience an intrinsic energy ceiling, and increased energy costs lead to a decline in self-maintenance and/or offspring provisioning.
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| 2. |
- Hicks, Olivia, et al.
(författare)
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Holding time has limited impact on constitutive innate immune function in a long-lived Antarctic seabird, the Adélie penguin : implications for field studies
- 2023
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Ingår i: Biology Open. - : The Company of Biologists. - 2046-6390. ; 12:2
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Tidskriftsartikel (refereegranskat)abstract
- There is great interest in measuring immune function in wild animals. Yet, field conditions often have methodological challenges related to handling stress, which can alter physiology. Despite general consensus that immune function is influenced by handling stress, previous studies have provided equivocal results. Furthermore, few studies have focused on long-lived species, which may have different stress-immune trade-offs compared to short-lived species that have primarily been tested. Here, we investigate whether capture and handling duration impacts innate immune function in a long-lived seabird, the Adélie penguin (Pygoscelis adeliae). We found no evidence for changes in three commonly used parameters of innate immune function upon holding time of up to 2 h, suggesting that immune function in this species is more robust against handling than in other species. This opens up exciting possibilities for measuring immune function in species with similar life-histories even if samples cannot be taken directly after capture.
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| 3. |
- Kato, Naoko, et al.
(författare)
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Development and psychometric properties of the Japanese heart failure knowledge scale
- 2013
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Ingår i: International Heart Journal. - : International Heart Journal Association. - 1349-2365 .- 1349-3299. ; 54:4, s. 228-233
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Tidskriftsartikel (refereegranskat)abstract
- Knowledge about their own condition is important for patients with heart failure (HF). No valid, reliable, and easily administered instrument is available to measure this knowledge in clinical practice. In this study, a HF knowledge scale was developed, and its psychometric properties were tested. Items related to knowledge about HF were extracted from relevant guidelines. Content validity of the items was confirmed by an expert panel including a cardiologist and nurses specialized in treatment and care of patients with HF. A self-administered questionnaire was then distributed to 187 patients with BY (64.0 +/- 12.1 years, males 69%). In 62% patients, a left ventricular ejection fraction of less than 50% was identified. Exploratory factor analysis demonstrated the one-dimensionality of the 15-item HF knowledge scale. Mean score was 10.7 +/- 3.0 (range, 0-15). Known-group validity testing revealed a significant difference in HF knowledge score between patients newly diagnosed with HF and patients experienced with HF (9.4 +/- 3.2 versus 10.8 +/- 2.9, P = 0.043). In addition, HF knowledge scale scores were correlated with HF self-care scores assessed by the European Heart Failure Self-Care Behavior Scale for evaluation of criterion validity (rho = 0.304, P less than 0.001). Cronbachs alpha was 0.79, and item-total correlation was 0.22-0.51, thereby suggesting that the reliability of the scale was acceptable. Acceptable validity and reliability were demonstrated for the HF knowledge scale developed in this study. This instrument could be useful in evaluation of patient knowledge about HF.
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| 4. |
- Le Vaillant, Maryline, et al.
(författare)
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Telomere length reflects individual quality in free-living adult king penguins
- 2015
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Ingår i: Polar Biology. - : Springer Science and Business Media LLC. - 0722-4060 .- 1432-2056. ; 38:12, s. 2059-2067
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Tidskriftsartikel (refereegranskat)abstract
- Growing evidence suggests that telomeres, non-coding DNA sequences that shorten with age and stress, are related in an undefined way to individual breeding performances and survival rates in several species. Short telomeres and elevated shortening rates are typically associated with life stress and low health. As such, telomeres could serve as an integrative proxy of individual quality, describing the overall biological state of an individual at a given age. Telomere length could be associated with the decline of an array of physiological traits in age-controlled individuals. Here, we investigated the links between individuals' relative telomere length, breeding performance and various physiological (body condition, natural antibody levels) and life history (age, past breeding success) parameters in a long-lived seabird species, the king penguin Aptenodytes patagonicus. While we observed no link between relative telomere length and age, we found that birds with longer telomeres arrived earlier for breeding at the colony, and had higher breeding performances (i.e. the amount of time adults managed to maintain their chicks alive, and ultimately breeding success) than individuals with shorter telomeres. Further, we observed a positive correlation between telomere length and natural antibody levels. Taken together, our results add to the growing evidence that telomere length is likely to reflect individual quality difference in wild animal.
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| 5. |
- Okada, Akiko, et al.
(författare)
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Psychometric properties of the Japanese version of the Self-Care of Heart Failure Index version 7.2
- 2023
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Ingår i: European Journal of Cardiovascular Nursing. - : OXFORD UNIV PRESS. - 1474-5151 .- 1873-1953.
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Tidskriftsartikel (refereegranskat)abstract
- Aims It is more important for patients with heart failure (HF) to objectively identify their self-care status. The Self-Care of Heart Failure Index (SCHFI) version 7.2 is a reliable and valid instrument comprising three scales: self-care maintenance, symptom perception, and self-care management. We aimed to translate the SCHFI v.7.2 into Japanese and test its validity and reliability. Methods and results This was a cross-sectional study. Two translators performed forward and backward translations between English and Japanese. To assess structural validity, confirmatory factor analyses were performed using the structure of the original version. To assess convergent validity, the associations between each scale and self-care self-efficacy were evaluated. To assess internal consistency, model-based internal consistency coefficients were calculated. Participants were 314 Japanese outpatients with HF (mean age: 72.8 +/- 12.8 years). Regarding structural validity, all scales showed adequate model fit indices, supporting a two-factor structure with items similar to those in the original version. However, to improve the model fit indices, it was necessary to add error correlations for the self-care maintenance and symptom perception scales. Regarding convergent validity, all scales showed significant associations with self-care self-efficacy. Regarding internal consistency, the model-based internal consistency coefficients were sufficient for all scales (0.739, 0.908, and 0.783 for the self-care maintenance, symptom perception, and self-care management scales, respectively). Conclusion The Japanese version of the SCHFI v.7.2 had adequate validity and reliability. This instrument is useful for assessing self-care in Japanese HF patients. However, factors influencing self-care should be considered when interpreting results. [GRAPHICS] .
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| 6. |
- Yoshimura, Takeshi, et al.
(författare)
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GlcNAc6ST-1 regulates sulfation of N-glycans and myelination in the peripheral nervous system
- 2017
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Ingår i: Scientific Reports. - : Nature Publishing Group. - 2045-2322. ; 7
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Tidskriftsartikel (refereegranskat)abstract
- Highly specialized glial cells wrap axons with a multilayered myelin membrane in vertebrates. Myelin serves essential roles in the functioning of the nervous system. Axonal degeneration is the major cause of permanent neurological disability in primary myelin diseases. Many glycoproteins have been identified in myelin, and a lack of one myelin glycoprotein results in abnormal myelin structures in many cases. However, the roles of glycans on myelin glycoproteins remain poorly understood. Here, we report that sulfated N-glycans are involved in peripheral nervous system (PNS) myelination. PNS myelin glycoproteins contain highly abundant sulfated N-glycans. Major sulfated N-glycans were identified in both porcine and mouse PNS myelin, demonstrating that the 6-O-sulfation of N-acetylglucosamine (GlcNAc-6-O-sulfation) is highly conserved in PNS myelin between these species. P-0 protein, the most abundant glycoprotein in PNS myelin and mutations in which at the glycosylation site cause Charcot-Marie-Tooth neuropathy, has abundant GlcNAc-6-O-sulfated N-glycans. Mice deficient in N-acetylglucosamine-6-O-sulfotransferase-1 (GlcNAc6ST-1) failed to synthesize sulfated N-glycans and exhibited abnormal myelination and axonal degeneration in the PNS. Taken together, this study demonstrates that GlcNAc6ST-1 modulates PNS myelination and myelinated axonal survival through the GlcNAc-6-O-sulfation of N-glycans on glycoproteins. These findings may provide novel insights into the pathogenesis of peripheral neuropathy.
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