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1.
Several anecdotal reports indicate that walruses (Odobenus rosmarus) occasionally attack seabirds, which potentially impacts local bird populations. However, the manner in which walruses interact with seabirds and the motivational basis of such interactions have not been investigated. Here, we describe and characterize the behaviour of wild Pacific walruses (O. r. divergens) directed at seabirds in water near the summer haulout in the Chukchi Sea. Although most walruses showed no interest in seabirds nearby, some individuals intentionally approached them both alone and in groups. A total of 74 seabird encounters for 71 individually identified walruses were registered. Behavioural analysis based on detailed observations, photography and video recording showed that the most common types of walrus behaviour toward a bird were approach by surfacing and splash, approach by surfacing and hit and attack from below. Immature individuals initiated 82% of encounters. The motivation to approach a bird was low in adult individuals, with the majority of encounters involving adults initiated by males. Walrus encounters with live birds showed a very low rate of bird kill. Encounters with dead birds were followed by further manipulations with bird carcasses, which included both the consumption of bird soft tissue and object play taking the form of drop–catch behaviour. In addition eight cases of the object-oriented play with a bird carcass in a group of walruses were observed. Object play in wild walruses is reported for the first time. Our results indicate that in seabird encounters, walruses display diverse behavioural patterns, not limited to predatory responses. 相似文献
2.
Emanuele Scollo David Neville M. Jose Oruna‐Concha Martine Trotin Rainer Cramer 《Proteomics》2018,18(3-4)
Cocoa seed storage proteins play an important role in flavour development as aroma precursors are formed from their degradation during fermentation. Major proteins in the beans of Theobroma cacao are the storage proteins belonging to the vicilin and albumin classes. Although both these classes of proteins have been extensively characterized, there is still limited information on the expression and abundance of other proteins present in cocoa beans. This work is the first attempt to characterize the whole cocoa bean proteome by nano‐UHPLC‐ESI MS/MS analysis using tryptic digests of cocoa bean protein extracts. The results of this analysis show that >1000 proteins could be identified using a species‐specific Theobroma cacao database. The majority of the identified proteins were involved with metabolism and energy. Additionally, a significant number of the identified proteins were linked to protein synthesis and processing. Several proteins were also involved with plant response to stress conditions and defence. Albumin and vicilin storage proteins showed the highest intensity values among all detected proteins, although only seven entries were identified as storage proteins. A comparison of MS/MS data searches carried out against larger non‐specific databases confirmed that using a species‐specific database can increase the number of identified proteins, and at the same time reduce the number of false positives. The results of this work will be useful in developing tools that can allow the comparison of the proteomic profile of cocoa beans from different genotypes and geographic origins. Data are available via ProteomeXchange with identifier PXD005586. 相似文献
3.
A. N. Giljov K. A. Karenina T. V. Ivkovich Y. B. Malashichev 《Russian Journal of Marine Biology》2016,42(2):196-198
Asymmetrical forelimb use is characteristic of many mammalian species. However, little is known about this phenomenon in cetaceans. We examined the asymmetry in pectoral flipper use by the wild orca Orcinus orca (Linnaeus, 1758). During observations from motor boats in the Avachinskii Bay (East Kamchatka) we recorded the use of flippers in slapping the water by individually identified resident (fish-eating) orcas. The studied individuals mostly used their right flipper. The revealed right-sided bias presumably reflects the pivotal role of the left brain hemisphere in the control of forelimb movements, which is consistent with the data that have been obtained for other cetacean species. 相似文献
4.
Andrea Aroldi Mario Mauri Daniele Ramazzotti Matteo Villa Federica Malighetti Valentina Crippa Federica Cocito Chiara Borella Elisa Bossi Carolina Steidl Chiara Scollo Claudia Voena Roberto Chiarle Luca Mologni Rocco Piazza Carlo Gambacorti-Passerini 《Journal of cellular and molecular medicine》2023,27(20):3053-3064
Mantle-cell lymphoma (MCL) is a B-cell non-Hodgkin Lymphoma (NHL) with a poor prognosis, at high risk of relapse after conventional treatment. MCL-associated tumour microenvironment (TME) is characterized by M2-like tumour-associated macrophages (TAMs), able to interact with cancer cells, providing tumour survival and resistance to immuno-chemotherapy. Likewise, monocyte-derived nurse-like cells (NLCs) present M2-like profile and provide proliferation signals to chronic lymphocytic leukaemia (CLL), a B-cell malignancy sharing with MCL some biological and phenotypic features. Antibodies against TAMs targeted CD47, a ‘don't eat me’ signal (DEMs) able to quench phagocytosis by TAMs within TME, with clinical effectiveness when combined with Rituximab in pretreated NHL. Recently, CD24 was found as valid DEMs in solid cancer. Since CD24 is expressed during B-cell differentiation, we investigated and identified consistent CD24 in MCL, CLL and primary human samples. Phagocytosis increased when M2-like macrophages were co-cultured with cancer cells, particularly in the case of paired DEMs blockade (i.e. anti-CD24 + anti-CD47) combined with Rituximab. Similarly, unstimulated CLL patients-derived NLCs provided increased phagocytosis when DEMs blockade occurred. Since high levels of CD24 were associated with worse survival in both MCL and CLL, anti-CD24-induced phagocytosis could be considered for future clinical use, particularly in association with other agents such as Rituximab. 相似文献
5.
Abdulkader F Azevedo-Martins AK Miranda Mde A Brunaldi K 《Advances in physiology education》2005,29(1):51-53
An important challenge for both students and teachers of physiology is to integrate the different areas in which physiological knowledge is didactically divided. In developing countries, such an issue is even more demanding, because budget restrictions often affect the physiology program with laboratory classes being the first on the list when it comes to cuts in expenses. With the aim of addressing this kind of problem, the graduate students of our department organized a physiology summer course offered to undergraduate students. The objective was to present the different physiological systems in an integrated fashion. The strategy pursued was to plan laboratory classes whose experimental results were the basis for the relevant theoretical discussions. The subject we developed to illustrate physiology integration was the study of factors influencing salivary secretion. 相似文献
6.
Background
Factors determining patterns of laterality manifestation in mammals remain unclear. In primates, the upright posture favours the expression of manual laterality across species, but may have little influence within a species. Whether the bipedalism acts the same in non-primate mammals is unknown. Our recent findings in bipedal and quadrupedal marsupials suggested that differences in laterality pattern, as well as emergence of manual specialization in evolution might depend on species-specific body posture. Here, we evaluated the hypothesis that the postural characteristics are the key variable shaping the manual laterality expression across mammalian species.Methodology/Principal Findings
We studied forelimb preferences in a most bipedal marsupial, brush-tailed bettong, Bettongia penicillata in four different types of unimanual behavior. The significant left-forelimb preference at the group level was found in all behaviours studied. In unimanual feeding on non-living food, catching live prey and nest-material collecting, all or most subjects were lateralized, and among lateralized bettongs a significant majority displayed left-forelimb bias. Only in unimanual supporting of the body in the tripedal stance the distribution of lateralized and non-lateralized individuals did not differ from chance. Individual preferences were consistent across all types of behaviour. The direction or the strength of forelimb preferences were not affected by the animals’ sex.Conclusions/Significance
Our findings support the hypothesis that the expression of manual laterality depends on the species-typical postural habit. The interspecies comparison illustrates that in marsupials the increase of bipedality corresponds with the increase of the degree of group-level forelimb preference in a species. Thus, bipedalism can predict pronounced manual laterality at both intra- and interspecific levels in mammals. We also conclude that quadrupedal position in biped species can slightly hinder the expression of manual laterality, but the evoked biped position in quadrupedal species does not necessarily lead to the enhanced manifestation of manual laterality. 相似文献7.
Marzocco S Di Paola R Genovese T Sorrentino R Britti D Scollo G Pinto A Cuzzocrea S Autore G 《Life sciences》2004,75(12):1417-1433
In the present study we evaluate the effect of methylguanidine (MG), a product of protein catabolism, in a model of acute inflammation (zymosan induced inflammation) in mice where oxyradical and nitric oxide (NO) play a crucial role. Our data show that MG, given intraperitoneally at the dose of 30 mg/Kg, inhibits the inflammatory response reducing significantly (P < 0.05) peritoneal exudates formation, mononuclear cell infiltration and histological injury in mice. Furthermore, our data suggests that there is a significant (P < 0.05) reduction in kidney, liver and pancreas injury as demonstrated by the reduction in amylase, lipase, creatinine, AST, ALT, bilirubine and alkaline phosfatase levels. MG is also able to reduce the appearance of nitrotyrosine and of the nuclear enzyme poly (adenosine diphosphate [ADP]-ribose) synthase (PARS) immunoreactivity in the inflamed intestinal and lung tissues. The histological examination revealed a significant reduction in zymosan-induced intestinal and lung damage in MG-treated mice. Taken together, the present results demonstrate that MG exerts potent anti-inflammatory effects on zymosan-induced shock. 相似文献
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9.
Jacqueline Bua Bibiana J. Volta Alina E. Perrone Karenina Scollo Elsa B. Velázquez Andres M. Ruiz Ana M. De Rissio Rita L. Cardoni 《PLoS neglected tropical diseases》2013,7(10)