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de la Fuente Mireia Bonada Núria Bêche Leah Dahm Clifford N. Mendez Patina K. Tockner Klement Uehlinger Urs Acuña Vicenç 《Hydrobiologia》2018,808(1):353-370
Hydrobiologia - Natural disturbances are agents of natural selection that drive multiple biological adaptations along evolutionary time. Frequent, high magnitude disturbances are expected to select... 相似文献
53.
Oxidative Stress Promotes Doxorubicin‐Induced Pgp and BCRP Expression in Colon Cancer Cells Under Hypoxic Conditions
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Conservation genetics of the franciscana dolphin in Northern Argentina: population structure,by-catch impacts,and management implications 总被引:1,自引:0,他引:1
Martin Mendez 《Conservation Genetics》2008,9(2):419-435
Evaluating population structure in the marine environment is a challenging task when the species of interest is continuously
distributed, and yet the use of population or stock structure is a crucial component of management and conservation strategies.
The franciscana dolphin (Pontoporia blainvillei), a rare endangered coastal cetacean, suffers high levels of by-catch all along its distribution range in the Western South
Atlantic, and questions have been raised about boundaries or divisions for population management. Here we apply genetic tools
to better understand population structure and migration, sex-biased dispersal, and to assess potential genetic and demographic
impacts of by-catch. Our analyses, based on mtDNA control region sequences, reveal significant genetic division at the regional
level and fine-scale structure within our study area. These results suggest that the population in northern Buenos Aires is
the most isolated population in Argentina. We found no significant departure from an equal sex ratio among the by-caught animals.
A few cases of multiple entanglements appeared to be mother–calf pairs based on field observations and individuals sharing
the same mtDNA control region lineage. The distribution of haplotype frequencies observed could imply that some maternal lineages
are more prone to be subject to higher rates of by-catch, although biopsy sampling is necessary to fully evaluate whether
maternal lineage distributions are the same for biopsy sampled and by-caught animals. A genetic indication of population size
disequilibrium was detected for all populations in Argentina, which is consistent with available rates of by-catch and abundance
estimates. Collectively, our findings support the current scheme of larger recognized Franciscana Management Areas (FMA),
but argue for a finer-scale subdivision within Northern Buenos Aires region (FMA IV). Finally, an integrated approach to promote
conservation of this endangered small cetacean has to involve identification of genetic and demographic threats, a more sustainable
fishery strategy to reduce by-catch, and designation of protected areas that are supported by underlying population structure
for franciscana dolphins. 相似文献
56.
Amogh Boloor Denise Hanway Maria Joshi David T. Winn Gabriel Mendez Marlena Walls Ping Wei Fuxin Qian Xiaoli Zhang Yuliang Zhang Michael E. Hepperle Xinqiang Li David A. Campbell Juan M. Betancort 《Bioorganic & medicinal chemistry letters》2009,19(19):5708-5711
A new series of NS3/4A protease boronic acid inhibitors is described. The compounds show good biochemical potency and cellular activity. The peptidomimetic inhibitors were evaluated against proteases from different HCV genotypes and clinically relevant NS3/4A mutants. Compound 28 displayed subnanomolar to single digit nanomolar potencies in the enzymatic assays and an EC50 of 25 nM in the replicon cell-based assay. 相似文献
57.
Two recombinant barley cystatins, HvCPI5 and HvCPI6, have been tested in vitro against promastigotes and intracellular amastigotes of Leishmania infantum in the J774 monocytic cell line. Toxicity of cystatins for J774 cells was also determined. In addition, a comparison between direct counts of intracellular amastigotes and quantitation of burden by Q-PCR was carried out. Low concentrations (2 μM) from both cystatins were unable to inhibit promastigote replication. HvCPI5 was toxic for mammalian cells; 0.1 μM reduced by more than 50% the cell viability. On the contrary, HvCPI6 did not exhibit any toxicity for J774 cells up to 6 μM and inhibited the intracellular amastigote multiplication. Dose-response analysis showed that 4.8 μM HvCPI6 reduced by >90% the intracellular parasite load and had an approximate IC50 value of 1.5 μM. Comparable results were obtained by direct counting of intracellular amastigotes and Q-PCR. Results point towards the direct inhibition of amastigote multiplication by HvCPI6 and the interest of this recombinant cystatin in the chemotherapy of leishmaniasis. 相似文献
58.
Wilkinson B Gregory MA Moss SJ Carletti I Sheridan RM Kaja A Ward M Olano C Mendez C Salas JA Leadlay PF vanGinckel R Zhang MQ 《Bioorganic & medicinal chemistry letters》2006,16(22):5814-5817
A set of novel borrelidin analogues have been prepared by precursor-directed biosynthesis. Structure-activity relationship analysis suggests that steric structural arrangement within the C17 side chain is important for differentiating cytotoxic and anti-angiogenic activities. A C17-cyclobutyl analogue 3 was found to have markedly increased selectivity for in vitro angiogenesis inhibition over cytotoxicity and is therefore potentially useful as an anticancer agent. 相似文献
59.
Incidental entanglement in fishing gear is arguably the most serious threat to many populations of small cetaceans, judging by the alarming number of captured animals. However, other aspects of this threat, such as the potential capture of mother-offspring pairs or reproductive pairs, could be equally or even more significant but have rarely been evaluated. Using a combination of demographic and genetic data we provide evidence that i) Franciscana dolphin pairs that are potentially reproductive and mother-offspring pairs form temporal bonds, and ii) are entangled simultaneously. Our results highlight potential demographic and genetic impacts of by-catch to cetacean populations: the joint entanglement of mother-offspring or reproductive pairs, compared to random individuals, might exacerbate the demographic consequences of by-catch, and the loss of groups of relatives means that significant components of genetic diversity could be lost together. Given the social nature of many odontocetes (toothed cetaceans), we suggest that these potential impacts could be rather general to the group and therefore by-catch could be more detrimental than previously considered. 相似文献
60.
Mendez M Gross KW Glenn ST Garvin JL Carretero OA 《The Journal of biological chemistry》2011,286(32):28608-28618
Renin is essential for blood pressure control. Renin is stored in granules in juxtaglomerular (JG) cells, located in the pole of the renal afferent arterioles. The second messenger cAMP stimulates renin release. However, it is unclear whether fusion and exocytosis of renin-containing granules is involved. In addition, the role of the fusion proteins, SNAREs (soluble N-ethylmaleimide-sensitive factor attachment proteins), in renin release from JG cells has not been studied. The vesicle SNARE proteins VAMP2 (vesicle associated membrane protein 2) and VAMP3 mediate cAMP-stimulated exocytosis in other endocrine cells. Thus, we hypothesized that VAMP2 and/or -3 mediate cAMP-stimulated renin release from JG cells. By fluorescence-activated cell sorting, we isolated JG cells expressing green fluorescent protein and compared the relative abundance of VAMP2/3 in JG cells versus total mouse kidney mRNA by quantitative PCR. We found that VAMP2 and VAMP3 mRNA are expressed and enriched in JG cells. Confocal imaging of primary cultures of JG cells showed that VAMP2 (but not VAMP3) co-localized with renin-containing granules. Cleavage of VAMP2 and VAMP3 with tetanus toxin blocked cAMP-stimulated renin release from JG cells by ~50% and impaired cAMP-stimulated exocytosis by ~50%, as monitored with FM1-43. Then we specifically knocked down VAMP2 or VAMP3 by adenoviral-mediated delivery of short hairpin silencing RNA. We found that silencing VAMP2 blocked cAMP-induced renin release by ~50%. In contrast, silencing VAMP3 had no effect on basal or cAMP-stimulated renin release. We conclude that VAMP2 and VAMP3 are expressed in JG cells, but only VAMP2 is targeted to renin-containing granules and mediates the stimulatory effect of cAMP on renin exocytosis. 相似文献