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101.
Bompadre Thiago F. V. Moretti Débora B. Sakita Gabriel Z. Ieda Egon H. Martinez Maria I. V. Fernandes Elisabete A. N. Machado-Neto Raul Abdalla Adibe L. Louvandini Helder 《Biological trace element research》2020,193(2):414-421
Biological Trace Element Research - Chromium (Cr) is a micromineral that is involved in the metabolism of carbohydrates, lipids, ammonia, and nucleic acids; thus, its supplementation can influence... 相似文献
102.
C. Cuello J. GomisC. Almiñana C. MasideJ. Sanchez-Osorio M.A. GilA. Sánchez I. ParrillaJ.M. Vazquez J. RocaE.A. Martinez 《Animal reproduction science》2013
The aims of this study were (1) to determine the effect of in vitro maturation (IVM) medium supplementation with MEM vitamins on in vitro embryo development and sensitivity to vitrification of Day 6 blastocysts and (2) to evaluate whether the addition of forskolin to in vitro culture (IVC) medium enhances blastocyst survival following Super Open Pulled Straw (SOPS) vitrification. Cumulus–oocyte complexes (COCs; n = 4000) were matured with 0.0% or 0.05% (v/v) MEM vitamins. After 44 h of IVM, the oocytes were in vitro fertilized, and presumptive zygotes were cultured. At Day 5 of IVC, embryos from both experimental groups were cultured for 24 h with 0 or 10 μM forskolin, achieving a 2 × 2 factorial design. The blastocyst formation rate was assessed on Day 6, and subsets of samples from the four experimental groups were vitrified (n = 469) or kept fresh (n = 546). Fresh and vitrified-warmed blastocysts were cultured for 24 h prior to embryo survival and total blastocyst cell number assessment. The MEM vitamins increased (P < 0.001) the blastocyst formation rate at Day 6, but they did not affect embryo survival after vitrification. In contrast, the addition of forskolin to the culture medium enhanced (P < 0.05) the blastocyst vitrification tolerance. The total blastocyst cell number was similar among the groups. In conclusion, supplementation with 0.05% MEM vitamins improved the blastocyst formation rate, and the addition of 10 μM forskolin to the culture medium increased survival in Day 6 in vitro-produced blastocysts after SOPS vitrification. 相似文献
103.
Hugo M. Martinez Jacob V. Maizel Jr Bruce A. Shapiro 《Journal of biomolecular structure & dynamics》2013,31(6):669-683
Abstract Using primary and secondary structure information of an RNA molecule, the program RNA2D3D automatically and rapidly produces a first-order approximation of a 3-dimensional conformation consistent with this information. Applicable to structures of arbitrary branching complexity and pseudoknot content, it features efficient interactive graphical editing for the removal of any overlaps introduced by the initial generating procedure and for making conformational changes favorable to targeted features and subsequent refinement. With emphasis on fast exploration of alternative 3D conformations, one may interactively add or delete base-pairs, adjacent stems can be coaxially stacked or unstacked, single strands can be shaped to accommodate special constraints, and arbitrary subsets can be defined and manipulated as rigid bodies. Compaction, whereby base stacking within stems is optimally extended into connecting single strands, is also available as a means of strategically making the structures more compact and revealing folding motifs. Subsequent refinement of the first-order approximation, of modifications, and for the imposing of tertiary constraints is assisted with standard energy refinement techniques. Previously determined coordinates for any part of the molecule are readily incorporated, and any part of the modeled structure can be output as a PDB or XYZ file. Illustrative applications in the areas of ribozymes, viral kissing loops, viral internal ribosome entry sites, and nanobiology are presented. 相似文献
104.
The leopard seal is widely distributed on the Antarctic pack ice, but a number of individuals are also thought to displace north from the pack ice to the sub-Antarctic Islands or venture even farther north. In Chile, the leopard seal has been reported mainly in the Fueguian Archipelago, with individuals sighted year-round; however, the data to date have been unable to determine whether it is the same individuals who remain year-round. Thus, one of the questions to be resolved is whether there is a northward dispersion of individuals from the Southern Ocean returning to the Antarctic continent, or alternatively if there is a potential sub-Antarctic population that delay or suspend their migration toward the Antarctic region. Opportunistic sightings of a solitary seal at Ballena Sound (53°41′S, 72°37′W), Magellan Region, Chile, were documented in photographs on six occasions from January to May 2012. Based on the review of the photographs, the leopard seal was identified as the same individual. This finding provides the first evidence of a long occupation by a leopard seal in the fjords and channels of Fueguian Region, suggesting the existence of a small population inhabiting the waters of Southern Chile year-round. 相似文献
105.
Chun Jung Chen Jennifer E. Cox Rodney P. Kincaid Angel Martinez Christopher S. Sullivan 《Journal of virology》2013,87(20):11135-11147
Hundreds of virus-encoded microRNAs (miRNAs) have been uncovered, but an in-depth functional understanding is lacking for most. A major challenge for the field is separating those miRNA targets that are biologically relevant from those that are not advantageous to the virus. Here, we show that miRNAs from related variants of the polyomavirus simian vacuolating virus 40 (SV40) have differing host target repertoires (targetomes) while their direct autoregulatory activity on virus-encoded early gene products is completely preserved. These results underscore the importance of miRNA-mediated viral gene autoregulation in some polyomavirus life cycles. More broadly, these findings imply that some host targets of virus-encoded miRNAs are likely to be of little selective advantage to the virus, and our approach provides a strategy for prioritizing relevant targets. 相似文献
106.
Paola Cacchio Rosita Contento Claudia Ercole Giorgio Cappuccio Maria Preite Martinez Aldo Lepidi 《Geomicrobiology journal》2013,30(8):497-509
Much is known about the bacterial precipitation of carbonate rocks, but comparatively little is known about the involvement of microbes in the formation of secondary mineral structures in caves. We hypothesized that bacteria isolated from calcareous stalactites, which are able to mediate CaCO3 precipitation in vitro, play a role in the formation of carbonate speleothems. We collected numerous cultivable calcifying bacteria from calcareous speleothems from Cervo cave, implying that their presence was not occasional. The relative abundance of calcifying bacteria among total cultivable microflora was found to be related to the calcifying activity in the stalactites. We also determined the δ 13C and δ 18 O values of the Cervo cave speleothems from which bacteria were isolated and of the carbonates obtained in vitro to determine whether bacteria were indeed involved in the formation of secondary mineral structures. We identified three groups of biological carbonates produced in vitro at 11°C on the basis of their carbon isotopic composition: carbonates with δ 13C values (a) slightly more positive, (b) more negative, and (c) much more negative than those of the stalactite carbonates. The carbonates belonging to the first group, characterized by the most similar δ 13C values to stalactites, were produced by the most abundant strains. Most of calcifying isolates belonged to the genus Kocuria. Scanning electron microscopy showed that dominant morphologies of the bioliths were sherulithic with fibrous radiated interiors. We suggest a mechanism of carbonate crystal formation by bacteria. 相似文献
107.
Occurrence of alternariol and alternariol monomethyl ether in beverages from the Entre Rios Province market, Argentina 总被引:1,自引:0,他引:1
Leticia Broggi Cora Reynoso Silvia Resnik Fernanda Martinez Vanesa Drunday Ángela Romero Bernal 《Mycotoxin Research》2013,29(1):17-22
One hundred and eighty five samples of red, white and rosé wines and different juices purchased in Entre Rios, Argentina, were analyzed for the Alternaria mycotoxins alternariol (AOH) and alternariol methyl ether (AME). White wines were analyzed after removal of alcohol by a nitrogen stream and concentrated. AOH in red wines was cleaned up by solid-phase extraction columns in series (octadecyl and amino propyl modified silica) and AME quantified directly on the sample. The juices were filtered and concentrated, and then all sample extracts were quantified by high performance liquid chromatography with photodiode array detector that allows confirmation through UV spectra. Method validation revealed a good sensitivity with adequate LOD and LOQ for AME and less sensitivity for AOH (i.e. white wine: AME 0.8 and 1.4 ng/mL, AOH 2 and 3.3 ng/mL; red wine: AME 0.1 and 0.2 ng/mL, AOH 4.5 and 7.5 ng/mL; apple juice: AME 1.7 and 2.8 ng/mL, AOH 5 and 9 ng/mL; other juices: AME 2.0 and 3.1 ng/mL, AOH 6 and 10 ng/mL). Recoveries in all cases were greater than 80 %. Four of 53 white wine samples were contaminated with AOH with a maximum level of 18 ng/mL, 6 of 56 samples of red wine had a maximum of 13 ng/mL, and 3 of 68 samples of juices had traces of AOH. AME was less frequently detected than AOH, and the LOD and LOQ for AME are smaller than for AOH. Only three samples of white wine and one of red wine were contaminated, but in only one white wine sample (AME 225 ng/mL) did the toxin level exceed the LOQ. 相似文献
108.
Christof Nolte Tim Jinks Xinghao Wang María Teresa Martinez Pastor Robb Krumlauf 《Developmental biology》2013
The products of Hox genes function in assigning positional identity along the anterior–posterior body axis during animal development. In mouse embryos, Hox genes located at the 3′ end of HoxA and HoxB complexes are expressed in nested patterns in the progenitors of the secondary heart field during early cardiogenesis and the combined activities of both of these clusters are required for proper looping of the heart. Using Hox bacterial artificial chromosomes (BACs), transposon reporters, and transgenic analyses in mice, we present the identification of several novel enhancers flanking the HoxB complex which can work over a long range to mediate dynamic reporter expression in the endoderm and embryonic heart during development. These enhancers respond to exogenously added retinoic acid and we have identified two retinoic acid response elements (RAREs) within these control modules that play a role in potentiating their regulatory activity. Deletion analysis in HoxB BAC reporters reveals that these control modules, spread throughout the flanking intergenic region, have regulatory activities that overlap with other local enhancers. This suggests that they function as shadow enhancers to modulate the expression of genes from the HoxB complex during cardiac development. Regulatory analysis of the HoxA complex reveals that it also has enhancers in the 3′ flanking region which contain RAREs and have the potential to modulate expression in endoderm and heart tissues. Together, the similarities in their location, enhancer output, and dependence on retinoid signaling suggest that a conserved cis-regulatory cassette located in the 3′ proximal regions adjacent to the HoxA and HoxB complexes evolved to modulate Hox gene expression during mammalian cardiac and endoderm development. This suggests a common regulatory mechanism, whereby the conserved control modules act over a long range on multiple Hox genes to generate nested patterns of HoxA and HoxB expression during cardiogenesis. 相似文献
109.
Daniela Volcan Almeida Camila de Martinez Gaspar Martins M��rcio de Azevedo Figueiredo Carlos Frederico Ceccon Lanes Adalto Bianchini Luis Fernando Marins 《Transgenic research》2013,22(1):75-88
Growth hormone (GH) transgenic fish are at a critical step for possible approval for commercialization. Since this hormone is related to salinity tolerance in fish, our main goal was to verify whether the osmoregulatory capacity of the stenohaline zebrafish (Danio rerio) would be modified by GH-transgenesis. For this, we transferred GH-transgenic zebrafish (T) from freshwater to 11 ppt salinity and analyzed survival as well as relative changes in gene expression. Results show an increased mortality in T versus non-transgenic (NT) fish, suggesting an impaired mechanism of osmotic acclimation in T. The salinity effect on expression of genes related to osmoregulation, the somatotropic axis and energy metabolism was evaluated in gills and liver of T and NT. Genes coding for Na+, K+-ATPase, H+-ATPase, plasma carbonic anhydrase and cytosolic carbonic anhydrase were up-regulated in gills of transgenics in freshwater. The growth hormone receptor gene was down-regulated in gills and liver of both NT and T exposed to 11 ppt salinity, while insulin-like growth factor-1 was down-regulated in liver of NT and in gills of T exposed to 11 ppt salinity. In transgenics, all osmoregulation-related genes and the citrate synthase gene were down-regulated in gills of fish exposed to 11 ppt salinity, while lactate dehydrogenase expression was up-regulated in liver. Na+, K+-ATPase activity was higher in gills of T exposed to 11 ppt salinity as well as the whole body content of Na+. Increased ATP content was observed in gills of both NT and T exposed to 11 ppt salinity, being statistically higher in T than NT. Taking altogether, these findings support the hypothesis that GH-transgenesis increases Na+ import capacity and energetic demand, promoting an unfavorable osmotic and energetic physiological status and making this transgenic fish intolerant of hyperosmotic environments. 相似文献
110.
Victor Vendrell Citlali Vázquez-Echeverría Iris López-Hernández Beatriz Durán Alonso Salvador Martinez Cristina Pujades Thomas Schimmang 《Mechanisms of development》2013,130(2-3):160-168
Fgf and Wnt signalling have been shown to be required for formation of the otic placode in vertebrates. Whereas several Fgfs including Fgf3, Fgf8 and Fgf10 have been shown to participate during early placode induction, Wnt signalling is required for specification and maintenance of the otic placode, and dorsal patterning of the otic vesicle. However, the requirement for specific members of the Wnt gene family for otic placode and vesicle formation and their potential interaction with Fgf signalling has been poorly defined. Due to its spatiotemporal expression during placode formation in the hindbrain Wnt8a has been postulated as a potential candidate for its specification. Here we have examined the role of Wnt8a during formation of the otic placode and vesicle in mouse embryos. Wnt8a expression depends on the presence of Fgf3 indicating a serial regulation between Fgf and Wnt signalling during otic placode induction and specification. Wnt8a by itself however is neither essential for placode specification nor redundantly required together with Fgfs for otic placode and vesicle formation. Interestingly however, Wnt8a and Fgf3 are redundantly required for expression of Fgf15 in the hindbrain indicating additional reciprocal interactions between Fgf and Wnt signalling. Further reduction of Wnt signalling by the inactivation of Wnt1 in a Wnt8a mutant background revealed a redundant requirement for both genes during morphogenesis of the dorsal portion of the otic vesicle. 相似文献