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991.
Design‐ and model‐based recommendations for detecting and quantifying an amphibian pathogen in environmental samples 下载免费PDF全文
Brittany A. Mosher Kathryn P. Huyvaert Tara Chestnut Jacob L. Kerby Joseph D. Madison Larissa L. Bailey 《Ecology and evolution》2017,7(24):10952-10962
Accurate pathogen detection is essential for developing management strategies to address emerging infectious diseases, an increasingly prominent threat to wildlife. Sampling for free‐living pathogens outside of their hosts has benefits for inference and study efficiency, but is still uncommon. We used a laboratory experiment to evaluate the influences of pathogen concentration, water type, and qPCR inhibitors on the detection and quantification of Batrachochytrium dendrobatidis (Bd) using water filtration. We compared results pre‐ and post‐inhibitor removal, and assessed inferential differences when single versus multiple samples were collected across space or time. We found that qPCR inhibition influenced both Bd detection and quantification in natural water samples, resulting in biased inferences about Bd occurrence and abundance. Biases in occurrence could be mitigated by collecting multiple samples in space or time, but biases in Bd quantification were persistent. Differences in Bd concentration resulted in variation in detection probability, indicating that occupancy modeling could be used to explore factors influencing heterogeneity in Bd abundance among samples, sites, or over time. Our work will influence the design of studies involving amphibian disease dynamics and studies utilizing environmental DNA (eDNA) to understand species distributions. 相似文献
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Multiple predators often have effects on their common prey populations that cannot be predicted by summing the effects of each predator at a time. When predators forage on the same vegetation substrate, intraguild interactions might cause emergent outcomes for the plants on which the predators co‐occur. We experimentally evaluated the effects of spiders and ants on herbivory and reproduction in the extrafloral nectary‐bearing tree Qualea multiflora (Vochysiaceae). Plants were divided in four experimental groups, depending on the presence or absence of ants and spiders. We compared the effects of each treatment on richness and abundance of chewing and sucking herbivores and on herbivory (leaf area loss). We also evaluated the impact of predators on the production of buds, fruits and seeds, and weight of the fruits. The presence of ants reduced the abundance and richness of spiders, but spiders did not affect the abundance and richness of ants. Only the removal of ants resulted in a significant increase in the abundance of herbivores and herbivore richness. Herbivory, however, was also affected by spiders. In addition, we found a significant interaction effect of ants and spiders on herbivory, indicating an emergent multiple predator effect. Neither ants nor spiders had an impact on the number of buds produced, number of fruits per bud, and seeds per fruits or fruit weight. This study highlights the importance of evaluating the effect of the predator fauna as a whole and not only one specific group on herbivory. 相似文献
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Larissa de Oliveira Souza Beltrão Mayara Pangracio Cacilda da Silva Souza 《Mycopathologia》2018,183(5):847-852
We discuss the sarcoid-like clinical presentation, a rare type of infiltrative paracoccidioidomycosis (PCM) that is almost exclusively cutaneous, involves the face and histologically has a tuberculoid granulomatous pattern with few fungi. It is often misdiagnosed. In endemic regions of Brazil, PCM is more common among men from rural areas, while women of a reproductive age appear to be protected. We report the sarcoid-like PCM in a female urban dweller and highlight the main findings of a literature review. 相似文献
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Xiaolei Wang Larissa Krasnova Kevin Binchia Wu Wei-Shen Wu Ting-Jen Cheng Chi-Huey Wong 《Bioorganic & medicinal chemistry letters》2018,28(16):2708-2712
Described here is the asymmetric synthesis of iminosugar 2b, a Lipid II analog, designed to mimic the transition state of transglycosylation catalyzed by the bacterial transglycosylase. The high density of functional groups, together with a rich stereochemistry, represents an extraordinary challenge for chemical synthesis. The key 2,6-anti- stereochemistry of the iminosugar ring was established through an iridium-catalyzed asymmetric allylic amination. The developed synthetic route is suitable for the synthesis of focused libraries to enable the structure–activity relationship study and late-stage modification of iminosugar scaffold with variable lipid, peptide and sugar substituents. Compound 2b showed 70% inhibition of transglycosylase from Acinetobacter baumannii, providing a basis for further improvement. 相似文献
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Kirrilly R. Thompson Larissa Clarkson Christopher B. Riley Mariette van den Berg 《Journal of applied animal welfare science : JAAWS》2018,21(4):347-361
Little is known about the horse health management practices of Australian horse caregivers (owners). This article presents findings from a convenience sample of 505 horse owners who participated in an online survey. No large-scale welfare issues were identified, but there were some areas of potential concern, including owners who did not regularly deworm their horses (4%), a lack of strategic parasite control (3.1%), and a lack of regular dental care (11%). Several participants did not have their horse’s hooves regularly shod or trimmed (2%), and 14% had an unqualified person maintain their horse’s hooves. One in five owners (19%) did not vaccinate their horses against tetanus. The findings are discussed in relation to current Australian horse health guidelines and traditional sources of horse health information, together with recommendations for providing horse owners with relevant information in relevant forms. 相似文献
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Larissa Osten Marion Kubitza Anna Rachel Gallagher Jürgen Kastner Heike Olbrich Uwe de Vries Frieder Kees Brigitte Lelongt Stefan Somlo Heymut Omran Ralph Witzgall 《Histochemistry and cell biology》2009,132(2):199-210
Nephronophthisis belongs to a family of recessive cystic kidney diseases and may arise from mutations in multiple genes. In
this report we have used a spontaneous mouse mutant of type 3 nephronophthisis to examine whether the doxycycline-inducible
synthesis of Timp-2, a natural inhibitor of matrix metalloproteinases, can influence renal cyst growth in transgenic mice.
Metalloproteinases may exert either a negative or a positive effect on the progression of cystic kidney disease, and we reasoned
that this may be most effectively examined by using a natural inhibitor. Surprisingly, already the application of doxycycline,
which also inhibits matrix metalloproteinases, accelerated renal cyst growth and led to increased renal fibrosis, an additional
effect of Timp-2 was not detected. The positive effect of doxycycline on kidney size was not due to a non-specific “anabolic
effect” but was specific for cystic kidneys because it was not observed in non-cystic kidneys. When looking for potential
metabolic changes we noticed that the urine of control animals led to an increase in the calcium response of LLC-PK1 cells, whereas the urine of doxycycline-treated mice showed the opposite effect and even antagonized the urine of control
animals. Further experiments demonstrated that the urine of control animals contained a heat-labile, proteinase K-resistant
substance which appears to be responsible for the induction of a calcium response in LLC-PK1 cells. We conclude that doxycycline accelerates cyst growth possibly by the induction of a substance which lowers the intracellular
calcium concentration. Our data also add a note of caution when interpreting phenotypes of animal models based upon the tet
system.
Larissa Osten and Marion Kubitza have contributed equally. 相似文献
1000.
Larissa Rosa de Oliveira Joseph I. Hoffman Erika Hingst-Zaher Patricia Majluf Mônica M. C. Muelbert João Stenghel Morgante William Amos 《Conservation Genetics》2008,9(6):1451-1466
The South American fur seal (Arctocephalus australis) is widely distributed, occurring along both the Atlantic and the Pacific coasts of South America. Previous work suggests
there may be more than one subspecies, highlighting the need for further study. Here, we combine traditional and geometric
morphometric analysis of skull shape and size with genetic data to compare two populations of South American fur seals, one
from Uruguay and one from Peru. As a control group we used material from the closely related species Arctocephalus gazella. Both techniques of morphometric analysis reveal pronounced geographic variation in size and shape of the skull, with Peruvian
specimens (n = 102) being larger than Uruguayan skulls (n = 133) and significant shape differences concentrated in the rostral region. Similarly, seven highly polymorphic microsatellite
loci reveal highly significant differences in allele frequency. Moreover, Bayesian analysis implemented using the program
structure reveals two separate clusters corresponding perfectly to the two populations, with an assignment test correctly placing over
98% of specimens in their population of origin. This degree of differentiation for both genetic and morphological traits suggests
complete and possibly prolonged isolation to the extent that we believe these populations should be considered distinct evolutionarily
significant units. 相似文献