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A phylogeographical perspective on the ex situ conservation of Aylacostoma (Thiaridae,Gastropoda) from the High Paraná River (Argentina–Paraguay)
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Roberto E. Vogler Ariel A. Beltramino Ellen E. Strong Juana G. Peso Alejandra Rumi 《Zoological Journal of the Linnean Society》2015,174(3):487-499
Aylacostoma Spix, 1827, contains species that are the subject of focused conservation efforts under the auspices of the ‘Aylacostoma Project’, the only ex situ conservation programme for freshwater gastropods in South America. Two species from the High Paraná River (Argentina–Paraguay) are included in this programme (Aylacostoma chloroticum Hylton Scott, 1954 and Aylacostoma brunneum Vogler & Peso, 2014), as their habitats have disappeared as a consequence of the filling of the Yacyretá Reservoir in the 1990s. At present, A. chloroticum is restricted to only one known wild population in a small and fragile habitat, and wild populations of A. brunneum are presumed to have gone extinct. We used partial sequences of the cytochrome oxidase subunit I gene to provide the first phylogeographical perspective on these species from a limited dataset containing representatives of several wild populations that are successfully being bred in captivity. We found low genetic diversity and two haplotypes in A. chloroticum, and absence of variation with one haplotype in A. brunneum. The reservoir's entry zone was identified to be of great interest for conservation, and is where we suggest re‐introductions and translocations should be targeted, to preserve the future evolutionary potential of the extant diversity. © 2015 The Linnean Society of London 相似文献
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Cristina Lemini Ruth Jaimez Alejandra Figueroa Lucía Martinez-Mota María Estela Avila Martha Medina 《Experimental Animals》2015,64(1):81-89
Rodent ovariectomy is an experimental method to eliminate the main source of sexual
steroids. This work explored for the first time the ovariectomy temporal changes induced
in the hemostatic coagulation markers: prothrombin time (PT), activated partial
thromboplastin time (aPTT), thrombin time (TT), and fibrinogen concentration (FIB) along
with uterine weight on adult female CD1 mice and Wistar rats. Uterine weight (Uw) was
assessed before ovariectomy (control), and 1, 3, 5, 7, 9, 16, and 21 days after surgery.
PT, aPTT, TT and FIB were estimated the same days, using reported standard techniques.
Ovariectomy decreased Uw, since day 1; and from day 10 to 21 reached the lowest values for
both species. After day 1, mice hemostatic parameters changed (PT +10%,
P<0.05; aPTT +53%, P<0.05; TT −24%,
P<0.05; FIB +67%, P<0.05). Rats showed
significant changes only in TT and FIB (TT −13%, P<0.001; FIB +65%,
P<0.001). Neither mice PT, aPTT and TT, recovered control values
after 21 days. In the rats from day 5 to 16 aPTT diminished (18–23%,
P<0.05) recovering to control values on day 21, TT after 9 days and PT
on day 16. In both species, FIB returned to its control values after 9 days. Ovariectomy
differentially altered the PT hemostatic parameter of mice and rats indicating a
non-equivalence among both species behaviour for experimental studies of blood
coagulation. 相似文献
126.
Fernández-Miranda G Trakala M Martín J Escobar B González A Ghyselinck NB Ortega S Cañamero M Pérez de Castro I Malumbres M 《Development (Cambridge, England)》2011,138(13):2661-2672
Mitosis is controlled by multiple kinases that drive cell cycle progression and prevent chromosome mis-segregation. Aurora kinase B interacts with survivin, borealin and incenp to form the chromosomal passenger complex (CPC), which is involved in the regulation of microtubule-kinetochore attachments and cytokinesis. Whereas genetic ablation of survivin, borealin or incenp results in early lethality at the morula stage, we show here that aurora B is dispensable for CPC function during early cell divisions and aurora B-null embryos are normally implanted. This is due to a crucial function of aurora C during these early embryonic cycles. Expression of aurora C decreases during late blastocyst stages resulting in post-implantation defects in aurora B-null embryos. These defects correlate with abundant prometaphase figures and apoptotic cell death of the aurora B-deficient inner cell mass. Conditional deletion of aurora B in somatic cells that do not express aurora C results in chromosomal misalignment and lack of chromosome segregation. Re-expression of wild-type, but not kinase-dead, aurora C rescues this defect, suggesting functional overlap between these two kinases. Finally, aurora B-null cells partially arrest in the presence of nocodazole, suggesting that this kinase is not essential for the spindle assembly checkpoint. 相似文献
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Claudia Alejandra Reyes-Valdez Gorgonio Ruiz-Campos Faustino Camarena-Rosales José Luis Castro-Aguirre Giacomo Bernardi 《Reviews in Fish Biology and Fisheries》2011,21(3):543-558
The population morphometric variation of the endangered freshwater killifish (Fundulus lima) was evaluated and compared with that of its euryhaline coastal relatives (F. parvipinnis parvipinnis and F. p. brevis) on the basis of 384 specimens from the Baja California peninsula, Mexico. Forty five standardized body distances were compared
by means of discriminant function analysis (DFA). Sixteen body distances were significant to distinguish two groups of populations
for F. lima: a first group represented by the Bebelamas and San Javier basins, and second group composed by the basins of San Ignacio,
La Purísima, San Luis, San Pedro and Las Pocitas. When all freshwater and coastal populations were compared, the southernmost
population of F. lima (Las Pocitas) showed a higher morphometric similarity with the southern coastal subspecies (F. p. brevis), while another southern population (San Pedro) had an intermediate position between the freshwater and coastal forms. This
study suggests the presence of five evolutionary units (three freshwater and two coastal) for the genus Fundulus in the Baja California peninsula. 相似文献
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Allorhogas cordobensis sp. nov. (Hymenoptera: Braconidae: Doryctinae) is described from the province of Córdoba, Argentina. Its representatives can be distinguished from all other known species of the genus by the unusual morphology of the ovipositor tip and the expanded clypeus apically. Remarkably, this species is also characterized by having a tridentate mandible, a feature known only in exodont braconids, mostly of the subfamily Alysiinae. The new species was reared from stem galls on Lycium cestroides, which constitutes the second record of an Allorhogas species associated with galls on representatives of the plant family Solanaceae. 相似文献
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