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Ignacio Fernández Jorge M.O. Fernandes Vânia P. Roberto Martina Kopp Catarina Oliveira Marta F. Riesco Jorge Dias Cymon J. Cox M. Leonor Cancela Elsa Cabrita Paulo Gavaia 《Biochimica et Biophysica Acta (BBA)/General Subjects》2019,1863(1):39-51
Background
Vitamin K (VK) is a fat-soluble vitamin known for its essential role in blood coagulation, but also on other biological processes (e.g. reproduction, brain and bone development) have been recently suggested. Nevertheless, the molecular mechanisms behind its particular function on reproduction are not yet fully understood.Methods
The potential role of VK on reproduction through nutritional supplementation in Senegalese sole (Solea senegalensis) was assessed by gonadal maturation and 11-ketosterone, testosterone and estriol plasma levels when fed with control or VK supplemented (1250?mg?kg?1 of VK1) diets along a six month trial. At the end, sperm production and quality (viability and DNA fragmentation) were evaluated. Circulating small non-coding RNAs (sncRNAs) in blood plasma from males were also studied through RNA-Seq.Results
Fish fed with dietary VK supplementation had increased testosterone levels and lower sperm DNA fragmentation. SncRNAs from blood plasma were found differentially expressed when nutritional and sperm quality conditions were compared. PiR-675//676//4794//5462 and piR-74614 were found up-regulated in males fed with dietary VK supplementation. Let-7g, let-7e(18nt), let-7a-1, let-7a-3//7a-2//7a-1, let-7e(23nt) and piR-675//676//4794//5462 were found to be up-regulated and miR-146a and miR-146a-1//146a-2//146a-3 down-regulated when fish with low and high sperm DNA fragmentation were compared. Bioinformatic analyses of predicted mRNAs targeted by sncRNAs revealed the potential underlying pathways.Conclusions
VK supplementation improves fish gonad maturation and sperm quality, suggesting an unexpected and complex regulation of the nutritional status and reproductive performance through circulating sncRNAs.General significance
The use of circulating sncRNAs as reliable and less-invasive physiological biomarkers in fish nutrition and reproduction has been unveiled. 相似文献133.
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Lippa B Pan G Corbett M Li C Kauffman GS Pandit J Robinson S Wei L Kozina E Marr ES Borzillo G Knauth E Barbacci-Tobin EG Vincent P Troutman M Baker D Rajamohan F Kakar S Clark T Morris J 《Bioorganic & medicinal chemistry letters》2008,18(11):3359-3363
Based on a high throughput screening hit, pyrrolopyrimidine inhibitors of the Akt kinase are explored. X-ray co-crystal structures of two lead series results in the understanding of key binding interactions, the design of new lead series, and enhanced potency. The syntheses of these series and their biological activities are described. Spiroindoline 13j is found to have an Akt1 kinase IC(50) of 2.4+/-0.6 nM, Akt cell potency of 50+/-19 nM, and provides 68% inhibition of tumor growth in a mouse xenograft model (50 mg/kg, qd, po). 相似文献
136.
Road building, land use and climate change: prospects for environmental governance in the Amazon 总被引:1,自引:0,他引:1
Perz S Brilhante S Brown F Caldas M Ikeda S Mendoza E Overdevest C Reis V Reyes JF Rojas D Schmink M Souza C Walker R 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2008,363(1498):1889-1895
Some coupled land-climate models predict a dieback of Amazon forest during the twenty-first century due to climate change, but human land use in the region has already reduced the forest cover. The causation behind land use is complex, and includes economic, institutional, political and demographic factors. Pre-eminent among these factors is road building, which facilitates human access to natural resources that beget forest fragmentation. While official government road projects have received considerable attention, unofficial road building by interest groups is expanding more rapidly, especially where official roads are being paved, yielding highly fragmented forest mosaics. Effective governance of natural resources in the Amazon requires a combination of state oversight and community participation in a 'hybrid' model of governance. The MAP Initiative in the southwestern Amazon provides an example of an innovative hybrid approach to environmental governance. It embodies a polycentric structure that includes government agencies, NGOs, universities and communities in a planning process that links scientific data to public deliberations in order to mitigate the effects of new infrastructure and climate change. 相似文献
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We extend the existing work on the time-optimal control of the basic SIR epidemic model with mass action contact rate. Previous
results have focused on minimizing an objective function that is a linear combination of the cost associated with using control
and either the outbreak size or the infectious burden. We instead, provide analytic solutions for the control that minimizes
the outbreak size (or infectious burden) under the assumption that there are limited control resources. We provide optimal
control policies for an isolation only model, a vaccination only model and a combined isolation–vaccination model (or mixed
model). The optimal policies described here contain many interesting features especially when compared to previous analyses.
For example, under certain circumstances the optimal isolation only policy is not unique. Furthermore the optimal mixed policy
is not simply a combination of the optimal isolation only policy and the optimal vaccination only policy. The results presented
here also highlight a number of areas that warrant further study and emphasize that time-optimal control of the basic SIR
model is still not fully understood. 相似文献