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91.
The ex situ population of maned wolves is not self‐sustaining due to poor reproduction, caused primarily by parental incompetence. Studies have shown that environmental enrichment can promote natural parental behaviors in zoo animals. The objective of this study was to determine the effects of environmental enrichment on behavioral and physiological responses of maned wolves. During an 8‐week experimental period, daily behavior observations and fecal sample collection were conducted on four adult wolves (2.2) individually housed in environments without enrichment. After 2 weeks, the wolves were chronologically provided with 2‐week intervals of hiding dead mice around the exhibit, no enrichment, and introduction of boomer balls. Responses of the wolves to enrichment were assessed based on activity levels and exploratory rates, as well as the level of corticoid metabolites in fecal samples collected daily throughout the study period. Providing wolves with environmental enrichment significantly increased exploratory behaviors (P<0.05), especially when mice were hidden in the enclosure. Fecal corticoid concentrations were increased during periods of enrichment in males (P<0.05), but not in females. Overall, there were no correlations between behavioral responses to enrichment and fecal corticoid levels. Behavioral results suggest that environmental enrichment elicits positive effects on the behavior of captive maned wolves. There is evidence suggesting that providing animals with ability to forage for food is a more effective enrichment strategy than introducing objects. There is need for a longer term study to determine the impact of environmental enrichment in this species. Zoo Biol 26:331–343, 2007. © 2007 Wiley‐Liss, Inc. 相似文献
92.
El-Mogharbel N Wakefield M Deakin JE Tsend-Ayush E Grützner F Alsop A Ezaz T Marshall Graves JA 《Genomics》2007,89(1):10-21
We isolated and characterized a cluster of platypus DMRT genes and compared their arrangement, location, and sequence across vertebrates. The DMRT gene cluster on human 9p24.3 harbors, in order, DMRT1, DMRT3, and DMRT2, which share a DM domain. DMRT1 is highly conserved and involved in sexual development in vertebrates, and deletions in this region cause sex reversal in humans. Sequence comparisons of DMRT genes between species have been valuable in identifying exons, control regions, and conserved nongenic regions (CNGs). The addition of platypus sequences is expected to be particularly valuable, since monotremes fill a gap in the vertebrate genome coverage. We therefore isolated and fully sequenced platypus BAC clones containing DMRT3 and DMRT2 as well as DMRT1 and then generated multispecies alignments and ran prediction programs followed by experimental verification to annotate this gene cluster. We found that the three genes have 58-66% identity to their human orthologues, lie in the same order as in other vertebrates, and colocate on 1 of the 10 platypus sex chromosomes, X5. We also predict that optimal annotation of the newly sequenced platypus genome will be challenging. The analysis of platypus sequence revealed differences in structure and sequence of the DMRT gene cluster. Multispecies comparison was particularly effective for detecting CNGs, revealing several novel potential regulatory regions within DMRT3 and DMRT2 as well as DMRT1. RT-PCR indicated that platypus DMRT1 and DMRT3 are expressed specifically in the adult testis (and not ovary), but DMRT2 has a wider expression profile, as it does for other mammals. The platypus DMRT1 expression pattern, and its location on an X chromosome, suggests an involvement in monotreme sexual development. 相似文献
93.
Meister J Weber D Martino V Sterner O Anke T 《Zeitschrift für Naturforschung. C, Journal of biosciences》2007,62(1-2):11-15
The medicinal plant Eupatorium arnottianum can be found in the Northeast and center of Argentina and the South of Bolivia. From plant material collected in Argentina an endophytic Phomopsis was isolated. The fungus was identified by microscopic features and analysis of its ITS sequence. Cultures yielded, besides mellein and nectriapyrone, a novel depsidone derivative for which we propose the name phomopsidone (1). The structure of 1 was determined from its spectroscopic data. 相似文献
94.
Janine M Ramsey A Townsend Peterson Oscar Carmona-Castro David A Moo-Llanes Yoshinori Nakazawa Morgan Butrick Ezequiel Tun-Ku Keynes de la Cruz-Félix Carlos N Ibarra-Cerde?a 《Memórias do Instituto Oswaldo Cruz》2015,110(3):339-352
Chagas disease is one of the most important yet neglected parasitic diseases in
Mexico and is transmitted by Triatominae. Nineteen of the 31 Mexican triatomine
species have been consistently found to invade human houses and all have been found
to be naturally infected with Trypanosoma cruzi. The present paper
aims to produce a state-of-knowledge atlas of Mexican triatomines and analyse their
geographic associations with T. cruzi, human demographics and
landscape modification. Ecological niche models (ENMs) were constructed for the 19
species with more than 10 records in North America, as well as for T.
cruzi. The 2010 Mexican national census and the 2007 National Forestry
Inventory were used to analyse overlap patterns with ENMs. Niche breadth was greatest
in species from the semiarid Nearctic Region, whereas species richness was associated
with topographic heterogeneity in the Neotropical Region, particularly along the
Pacific Coast. Three species, Triatoma longipennis, Triatoma
mexicana and Triatoma barberi, overlapped with the
greatest numbers of human communities, but these communities had the lowest
rural/urban population ratios. Triatomine vectors have urbanised in most regions,
demonstrating a high tolerance to human-modified habitats and broadened historical
ranges, exposing more than 88% of the Mexican population and leaving few areas in
Mexico without the potential for T. cruzi transmission. 相似文献
95.
96.
97.
Brent W. Simpson Janine M. May David J. Sherman Daniel Kahne Natividad Ruiz 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2015,370(1679)
The cell surface of most Gram-negative bacteria is covered with lipopolysaccharide (LPS). The network of charges and sugars provided by the dense packing of LPS molecules in the outer leaflet of the outer membrane interferes with the entry of hydrophobic compounds into the cell, including many antibiotics. In addition, LPS can be recognized by the immune system and plays a crucial role in many interactions between bacteria and their animal hosts. LPS is synthesized in the inner membrane of Gram-negative bacteria, so it must be transported across their cell envelope to assemble at the cell surface. Over the past two decades, much of the research on LPS biogenesis has focused on the discovery and understanding of Lpt, a multi-protein complex that spans the cell envelope and functions to transport LPS from the inner membrane to the outer membrane. This paper focuses on the early steps of the transport of LPS by the Lpt machinery: the extraction of LPS from the inner membrane. The accompanying paper (May JM, Sherman DJ, Simpson BW, Ruiz N, Kahne D. 2015 Phil. Trans. R. Soc. B
370, 20150027. (doi:10.1098/rstb.2015.0027)) describes the subsequent steps as LPS travels through the periplasm and the outer membrane to its final destination at the cell surface. 相似文献
98.
99.
Epstein-Barr-related herpesviruses, or lymphocryptoviruses (LCV), naturally infect humans and nonhuman primates (NHP), but their host range is not well characterized. Using LCV and B cells from multiple species of Hominidae and Cercopithecidae, we show that LCV can immortalize B cells from some nonnative species but that growth transformation is restricted to B cells from their own family of hominoids or Old World NHP, suggesting a high degree of LCV adaptation to their natural primate host. 相似文献
100.