University Catolica Argentina

CABA, Argentina

University Catolica Argentina

CABA, Argentina
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Sansinena M.J.,University Catolica Argentina | Lynn J.,Louisiana State University | Bondioli K.R.,Louisiana State University | Denniston R.S.,Louisiana State University | Godke R.A.,Louisiana State University
Zygote | Year: 2011

Although interspecies somatic cell nuclear transfer (iSCNT) has potential applications in the conservation of exotic species, an in vitro developmental block has been observed in embryos produced by this approach. It has been suggested that mitochondrial mismatch between donor cell and recipient oocyte could cause embryonic developmental arrest. A series of experiments was conducted to investigate the effect of mixed mitochondrial populations (heteroplasmy) on early development of iSCNT-derived cloned embryos. The effect of combining the techniques of ooplasm transfer (OT) and somatic cell nuclear transfer (SCNT) was examined by monitoring in vitro embryonic development; the presence and pattern of migration of foreign mitochondria after OT was analysed by MitoTracker staining. In addition, the effect of transferring caprine ooplasm (iOT) into the bovine enucleated oocytes used in iSCNT was analysed. There was no significant effect of the sequence of events (OT-SCNT or SCNT-OT) on the number of fused, cleaved, blastocyst or hatched blastocyst stage embryos. MitoTracker Green staining of donor oocytes used for OT confirmed the introduction of foreign mitochondria. The distribution pattern of transferred mitochondria most commonly remained in a distinct cluster after 12, 74 and 144 h of in vitro culture. When goat ooplasm was injected into bovine enucleated oocytes (iSCNT), there was a reduction (p < 0.05) in fusion (52 vs. 82%) and subsequent cleavage rates (55 vs. 78%). The procedure of iOT prior to iSCNT had no effect in overcoming the 8-to 16-cell in vitro developmental block, and only parthenogenetic cow and goat controls reached the blastocyst (36 and 32%) and hatched blastocyst (25 and 12%) stages, respectively. This study indicates that when foreign mitochondria are introduced at the time of OT, these organelles tend to remain as distinct clusters without relocation after a few mitotic divisions. Although the bovine cytoplast appears capable of supporting mitotic divisions after iOT-iSCNT, heteroplasmy or mitochondrial incompatibilities may affect nuclear-ooplasmic events occurring at the time of genomic activation. © 2010 Cambridge University Press.


Redelico F.O.,University Catolica Argentina | Redelico F.O.,University of Buenos Aires | Proto A.N.,University Catolica Argentina | Proto A.N.,National University of Central Buenos Aires | And 2 more authors.
Journal of Physics: Conference Series | Year: 2010

This work describes a method for searching for globalization evidence within Latin American countries using correlation networks methods. Two correlation measures are used, one based on the usual Pearsons Correlation Coefficient and the other based on Mutual Information. First, it is pointed out there is a core of globalization, where no trade blocs appear, within Latin American countries and second, a hierarchy, from a globalization point of view, is found within these countries. There is no intention to enter into a political consideration here, though any politically prone reader may guess that some further consideration is in order. © 2010 IOP Publishing Ltd.


Huarte H.R.,University Catolica Argentina | Luna V.,National University of Rio Cuarto | Zavala J.A.,INBA Catedra de Bioquimica | Benech-Arnold R.L.,University of Buenos Aires
Seed Science Research | Year: 2014

Fluctuating temperatures terminate seed dormancy in many species, including Cynara cardunculus (L.) var. sylvestris. Termination of physiological dormancy requires low ratios of abscisic acid (ABA)/gibberellins (GA). In a previous paper we have shown that physiological responses to fluctuating temperatures comprise a reduction of abscisic acid (ABA) content and sensitivity. However, a possible stimulation of GA synthesis was also suggested as part of the mechanism. That possible stimulation, as well as the identification of potential regulatory sites for ABA and GA metabolism and signalling involved in the termination of dormancy by fluctuating temperatures, are yet to be determined. In this study, we measured GA content and sensitivity in seeds incubated under constant and fluctuating temperatures. We also assessed the expression of several genes involved in ABA and GA metabolism and signalling. Our results show that fluctuating temperatures reduce ABA/GA ratios through a reduction in ABA accumulation during incubation but without altering GA synthesis as compared to that observed under constant temperatures. On the other hand, fluctuating temperatures did not increase sensitivity to GA. Fluctuating temperatures reduced the expression of CycaNCED and CycaABI5 (ABA synthesis and signalling genes) with a temporal pattern that coincides with the interruption of ABA accumulation that precedes germination of seeds incubated under fluctuating temperatures. However, fluctuating temperatures did not modify the expression of CycaCYP707A2 (ABA inactivation) as compared to that observed under constant temperatures. Consistent with our determinations of GA content and sensitivity, fluctuating temperatures did not modify the expression of GA synthesis (CycaGA3ox) and signalling genes (CycaRGL2 and CycaGAI) in relation to that observed at constant temperatures. These results show that fluctuating temperatures terminate dormancy in Cynara cardunculus seeds through an interruption in ABA accumulation and a reduction in ABA signalling exerted at the level of CycaNCED and CycaABI5 expression. © 2014 Cambridge University Press.


Huarte H.R.,University Catolica Argentina | Pereyra Zorraquin M.,University Catolica Argentina | Bursztyn E.M.,University Catolica Argentina | Zapiola M.L.,Monsanto Corporation | Zapiola M.L.,University Catolica Argentina
Weed Science | Year: 2016

Common teasel is an invasive and widespread weed in Argentina. Germination experiments were carried out from 2011 to 2014 to determine the effect of various environmental factors on germination and emergence. Germination of recently dispersed seeds was 12% in darkness at constant temperature. In contrast, seed exposure to light and alternating temperatures enhanced germination to 95%. The requirement of light and alternating temperatures suggest that common teasel has physiological dormancy. Several experiments were carried out to determine whether (1) seed responses to light and alternating temperatures have a hormonal basis, (2) seed coats can suppress germination, and (3) time and thermal conditions during seed storage reduce light and alternating temperature requirements. Germination was reduced (≤13%) by a gibberellin synthesis inhibitor. In contrast, the presence of gibberellins and an abscisic acid synthesis inhibitor increased germination to 95 and 38%, respectively. Results suggest that a higher ratio among gibberellins and abscisic acid (GA/ABA) leads to a break in dormancy. Germination was 100% when embryos were excised, suggesting that seed coats may suppress germination by mechanical restriction. Likewise, germination was enhanced by hydrogen peroxide (70%). This compound is known to increase GA/ABA ratio in agreement with a hormonal control of dormancy proposed for common teasel. An increment of storage time reduces light and alternating temperature requirements, allowing seeds to germinate in darkness. Taking these results together confirms that common teasel has physiological dormancy. Seedling emergence was progressively reduced from 70 to 8% by increased burial depth from 0 to 3 cm. Information from these experiments may facilitate development of effective management for common teasel. Nomenclature: Common teasel Dipsacus fullonum L. DIFU2.


In the United Kingdom, during the mid-20th century, Paul Wood appears as the new leader of European cardiology. He introduced rigorous bed-side diagnostic methods and the confirmation of these clinical findings by cardiac catheterization, in an effort to demonstrate the pathophysiological causes of cardiac disease. In his search for the correct diagnosis, his comments, which could be caustic, both impressed and offended many. He had a strong commanding personality and was intensely honest in his appreciations. His showmanship and diagnostic ability became renown. In 1950, the publishing of the first edition of his textbook "Diseases of the Heart and Circulation" brought him worldwide recognition. In this book, Wood introduces his personal fresh style of narrative and his physiologic approach to cardiology. His intense professional activity, teaching, lecturing and preparing the third edition of his book, plus the fact that he was a heavy smoker, must have been the factors that lead to a myocardial infarction and death at the early age of 54. As Paul Dudley White and Ignacio Chávez in America, Paul Wood in Europe will be remembered as the emblematic figure leading the transition of cardiology into the modern era.


Cabeza Monroy G.M.,University Catolica Argentina
Vertex (Buenos Aires, Argentina) | Year: 2010

This study examines Axis I comorbidity in patients with borderline personality disorder as compared with patients with other personality disorders and to patients without personality disorders. A total of 235 clinical histories were evaluated. These were divided into three groups: 92 pertaining to patients with borderline personality disorder, 69 to ones having other personality disorders and 74 to patients without personality disorders. For purposes of statistical analysis, ANOVA and chi-square were employed. There were 89 (96.7%) patients with borderline personality disorder who had at least one Axis I diagnosis, and 13 (16.3%) who had three or more diagnoses, significantly higher in comparison to other groups (p = 0.0001). The comorbidity of Axis I diagnoses and borderline personality disorder was found to be high. Borderline personality disorder was significantly associated with mood, anxiety and substance use disorders. A prospective investigation is suggested.


Redelico F.O.,University Catolica Argentina | Redelico F.O.,University of Buenos Aires | Piacquadio M.N.,University of Buenos Aires
Journal of Physics: Conference Series | Year: 2010

The search for laws governing the occurrence of financial crashes is one of the most important activities in the field of econophysics. In this contribution the daily fluctuation of the price at the close time series before the April 2000 crash NASDAQ100 is analyzed using fractal geometry, two multifractal spectra are derived and a new instability index is presented in order to enlighten the results obtained within these spectra. Using these methods, empirical evidence of the usefullness of the discrete Chakrabarti-Stinchcombre model for earthquakes to describing the rising part of a speculative buble leading a crash is found. © 2010 IOP Publishing Ltd.


Hutin A.,University Catolica Argentina | Turchetti E.,University Catolica Argentina | Montesano J.,University Catolica Argentina | Dipietro A.,University Catolica Argentina
International Journal of Hydrogen Energy | Year: 2010

The intention of the present Paper is to warn of a possible scenario, in reference to the knowledge the population has about the energetic matter, we designed different techniques to know their opinions, ideas and suggestions. The final result of the first stage sheds light on the fact that there is a generalized interest in the energetic theme, but the knowledge about it, is nearly none. Different opinions prove the need to deepen the results obtained and the responsibilities that fall to us as researchers and professors. It is impossible to sustain over time changes in habits of the population in the use of energy, without having created and launched a project with: clear objectives and specific methodologies and techniques, taking into account the areas, regions and socioeconomic situation, in order to carry it out in time. © 2009 Professor T. Nejat Veziroglu. Published by Elsevier Ltd. All rights reserved.


Huarte H.R.,University Catolica Argentina | Carmona A.J.R.,University Catolica Argentina | Zapiola M.L.,University Catolica Argentina
Weed Technology | Year: 2014

Understanding seed biology and onset of germination requirements is a key point for designing effective weed management programs. Gibberellins (GAs) are known to play a role in onset of germination of several species. Onset of germination often requires an increase in de novo GA content or an increase in sensitivity to GAs. Reduced germination of seeds incubated in solutions containing compounds that inhibit GA synthesis provide evidence that GAs are required to trigger germination. Trinexapac-ethyl (TE), a GA synthesis inhibitor, is frequently used as a plant growth regulator in crop production. However, to the best of our knowledge, TE has not been used to study the requirement of GAs in onset of germination. Germination studies were conducted using seeds of artichoke thistle and common teasel under a range of TE concentrations (0 to 500 μM TE), a combined solution of 125 μM TE + 100 μM GA3 for artichoke, and 250 μM TE + 100 μM GA3 for common teasel. Germination tests were conducted at 20/10 C (12-h thermoperiod) in darkness for artichoke and at constant 15 C with 12 h of light for common teasel. Germination of artichoke in 125 μM TE was reduced to 47% when compared with the check (95%), but the combined TE + GA3 solution maintained germination at 84%. Germination of common teasel in 250 μM TE was reduced to 10% when compared with the check (91%), and the combined TE + GA3 solution increased germination to 63%. These results demonstrate the utility of TE to study the role of GAs in onset of germination. This novel use of TE is a valuable option to study germination requirements of weed species, and therefore contributes to the design of weed management programs. Nomenclature: Gibberellins; trinexapac-ethyl; prohexadione-calcium; artichoke thistle, Cynara cardunculus L. CYCA; common teasel, Dipsacus fullonum L. DIFU2.


PubMed | University Catolica Argentina
Type: Journal Article | Journal: Zygote (Cambridge, England) | Year: 2011

Although interspecies somatic cell nuclear transfer (iSCNT) has potential applications in the conservation of exotic species, an in vitro developmental block has been observed in embryos produced by this approach. It has been suggested that mitochondrial mismatch between donor cell and recipient oocyte could cause embryonic developmental arrest. A series of experiments was conducted to investigate the effect of mixed mitochondrial populations (heteroplasmy) on early development of iSCNT-derived cloned embryos. The effect of combining the techniques of ooplasm transfer (OT) and somatic cell nuclear transfer (SCNT) was examined by monitoring in vitro embryonic development; the presence and pattern of migration of foreign mitochondria after OT was analysed by MitoTracker staining. In addition, the effect of transferring caprine ooplasm (iOT) into the bovine enucleated oocytes used in iSCNT was analysed. There was no significant effect of the sequence of events (OT-SCNT or SCNT-OT) on the number of fused, cleaved, blastocyst or hatched blastocyst stage embryos. MitoTracker Green staining of donor oocytes used for OT confirmed the introduction of foreign mitochondria. The distribution pattern of transferred mitochondria most commonly remained in a distinct cluster after 12, 74 and 144 h of in vitro culture. When goat ooplasm was injected into bovine enucleated oocytes (iSCNT), there was a reduction (p < 0.05) in fusion (52 vs. 82%) and subsequent cleavage rates (55 vs. 78%). The procedure of iOT prior to iSCNT had no effect in overcoming the 8- to 16-cell in vitro developmental block, and only parthenogenetic cow and goat controls reached the blastocyst (36 and 32%) and hatched blastocyst (25 and 12%) stages, respectively. This study indicates that when foreign mitochondria are introduced at the time of OT, these organelles tend to remain as distinct clusters without relocation after a few mitotic divisions. Although the bovine cytoplast appears capable of supporting mitotic divisions after iOT-iSCNT, heteroplasmy or mitochondrial incompatibilities may affect nuclear-ooplasmic events occurring at the time of genomic activation.

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