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51.
H. B. Fantham M.A. D.Sc. F.R.S.S.Af. F.Z.S. Annie Porter D.Sc. F.R.S.S.Af. 《Journal of Zoology》1943,113(1-2):25-30
The morphology of Plasmodium struthionis , sp. n., parasitic in Sudanese ostriches, Struthio camelus , is described and figured. It is shown to differ morphologically from the species now considered valid, and also is smaller and different from the unnamed Plasmodium from the emu, described shortly by Carini and Maciel. The hosts belong to nearly related families and the parasites may eventually prove to belong to a small natural group.
The occurrence of Sarcosporidia in fishes is recorded for the first time. Sarcocystis salvelini , sp. n., parasitic in the abdominal muscles of Canadian speckled trout, Salvelinus fontinalis , is described and illustrated. A different species of Sarcocystis is notified from the eel pout, Zoarces angularis , obtained in Montreal. 相似文献
The occurrence of Sarcosporidia in fishes is recorded for the first time. Sarcocystis salvelini , sp. n., parasitic in the abdominal muscles of Canadian speckled trout, Salvelinus fontinalis , is described and illustrated. A different species of Sarcocystis is notified from the eel pout, Zoarces angularis , obtained in Montreal. 相似文献
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We describe a novel 3D fibrin matrix model using recombinant hematopoietic stem cell cytokines under serum-free defined conditions which promotes the assembly of human endothelial cell (EC) tubes with co-associated pericytes. Individual ECs and pericytes are randomly mixed together and EC tubes form that is accompanied by pericyte recruitment to the EC tube abluminal surface over a 3-5 day period. These morphogenic processes are stimulated by a combination of the hematopoietic stem cell cytokines, stem cell factor, interleukin-3, stromal derived factor-1α, and Flt-3 ligand which are added in conjunction with fibroblast growth factor (FGF)-2 into the fibrin matrix. In contrast, this tube morphogenic response does not occur under serum-free defined conditions when VEGF and FGF-2 are added together in the fibrin matrices. We recently demonstrated that VEGF and FGF-2 are able to prime EC tube morphogenic responses (i.e. added overnight prior to the morphogenic assay) to hematopoietic stem cell cytokines in collagen matrices and, interestingly, they also prime EC tube morphogenesis in 3D fibrin matrices. EC-pericyte interactions in 3D fibrin matrices leads to marked vascular basement membrane assembly as demonstrated using immunofluorescence and transmission electron microscopy. Furthermore, we show that hematopoietic stem cell cytokines and pericytes stimulate EC sprouting in fibrin matrices in a manner dependent on the α5β1 integrin. This novel co-culture system, under serum-free defined conditions, allows for a molecular analysis of EC tube assembly, pericyte recruitment and maturation events in a critical ECM environment (i.e. fibrin matrices) that regulates angiogenic events in postnatal life. 相似文献
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Zavala-Ortiz Daniel Arturo Ebel Bruno Guedon Emmanuel Marc Annie Barradas-Dermitz Dulce María Hayward-Jones Patricia Margaret Aguilar-Uscanga María Guadalupe 《Bioprocess and biosystems engineering》2020,43(4):747-752
Bioprocess and Biosystems Engineering - Plant suspension culture is attracting interest as a promising platform to produce biological medicines due to the absence of virus, prions or DNA related to... 相似文献
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Ping Ren Valrie Nron Sergio Rossi Eryuan Liang Mathieu Bouchard Annie Deslauriers 《Global Change Biology》2020,26(4):2072-2080
Climate change is altering phenology; however, the magnitude of this change varies among taxa. Compared with phenological mismatch between plants and herbivores, synchronization due to climate has been less explored, despite its potential implications for trophic interactions. The earlier budburst induced by defoliation is a phenological strategy for plants against herbivores. Here, we tested whether warming can counteract defoliation‐induced mismatch by increasing herbivore‐plant phenological synchrony. We compared the larval phenology of spruce budworm and budburst in balsam fir, black spruce, and white spruce saplings subjected to defoliation in a controlled environment at temperatures of 12, 17, and 22°C. Budburst in defoliated saplings occurred 6–24 days earlier than in the controls, thus mismatching needle development from larval feeding. This mismatch decreased to only 3–7 days, however, when temperatures warmed by 5 and 10°C, leading to a resynchronization of the host with spruce budworm larvae. The increasing synchrony under warming counteracts the defoliation‐induced mismatch, disrupting trophic interactions and energy flow between forest ecosystem and insect populations. Our results suggest that the predicted warming may improve food quality and provide better growth conditions for larval development, thus promoting longer or more intense insect outbreaks in the future. 相似文献
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Oliver Selmoni Elia Vajana Annie Guillaume Estelle Rochat Stphane Joost 《Molecular ecology resources》2020,20(1):154-169
An increasing number of studies are using landscape genomics to investigate local adaptation in wild and domestic populations. Implementation of this approach requires the sampling phase to consider the complexity of environmental settings and the burden of logistical constraints. These important aspects are often underestimated in the literature dedicated to sampling strategies. In this study, we computed simulated genomic data sets to run against actual environmental data in order to trial landscape genomics experiments under distinct sampling strategies. These strategies differed by design approach (to enhance environmental and/or geographical representativeness at study sites), number of sampling locations and sample sizes. We then evaluated how these elements affected statistical performances (power and false discoveries) under two antithetical demographic scenarios. Our results highlight the importance of selecting an appropriate sample size, which should be modified based on the demographic characteristics of the studied population. For species with limited dispersal, sample sizes above 200 units are generally sufficient to detect most adaptive signals, while in random mating populations this threshold should be increased to 400 units. Furthermore, we describe a design approach that maximizes both environmental and geographical representativeness of sampling sites and show how it systematically outperforms random or regular sampling schemes. Finally, we show that although having more sampling locations (between 40 and 50 sites) increase statistical power and reduce false discovery rate, similar results can be achieved with a moderate number of sites (20 sites). Overall, this study provides valuable guidelines for optimizing sampling strategies for landscape genomics experiments. 相似文献
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Prasanna Maruthi Podsiadla-Bialoskorska Malgorzata Mielecki Damian Ruffier Nicolas Fateh Amina Lambert Annie Fanuel Mathieu Camberlein Emilie Szolajska Ewa Grandjean Cyrille 《Glycoconjugate journal》2021,38(4):437-446
Glycoconjugate Journal - Virus-Like Particles (VLPs) have been used as immunogenic molecules in numerous recombinant vaccines. VLPs can also serve as vaccine platform to exogenous antigens, usually... 相似文献
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Bobby G. Ng Paulina Sosicka François Fenaille Annie Harroche Sandrine Vuillaumier-Barrot Mindy Porterfield Zhi-Jie Xia Shannon Wagner Michael J. Bamshad Marie-Christine Vergnes-Boiteux Sophie Cholet Stephen Dalton Anne Dell Thierry Dupré Mathieu Fiore Stuart M. Haslam Yohann Huguenin Tadahiro Kumagai Hudson H. Freeze 《American journal of human genetics》2021,108(6):1040-1052
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