Valeria Godoy | Universidad Finis Terrae (original) (raw)

Papers by Valeria Godoy

It is known that human syncytiotrophoblast (hSCT) actively transports more than 80% of the Ca 2þ ... more It is known that human syncytiotrophoblast (hSCT) actively transports more than 80% of the Ca 2þ that goes from maternal to fetal circulation. Transepithelial transport of Ca 2þ is carried out through channels, transporters and exchangers located in both microvillous (MVM) and basal (BM) plasma membranes. The plasma membrane Ca-ATPase (PMCA) is the most important mechanism of Ca 2þ homeostasis control in the human placenta. In this work, we reexamined the distribution of PMCA in isolated hSCT of term placenta. The PMCA activity was determined in isolated hSCT plasma membranes. A partial characterization of the PMCA activity was performed, including an evaluation of the sensitivity of this enzyme to an in vitro induced lipid peroxidation. Expression of the PMCA in hSCT plasma membranes and tissue sections was investigated using Western blots and immunohistochemistry, respectively. Our study demonstrates, for the first time, a correlation between the activity and structural distribution of PMCA in both MVM and BM of hSCT. It also demonstrates a higher PMCA activity and expression in MVM as compared to BM. Finally, PMCA4 seems to be preferentially distributed in both hSCT plasma membranes, while PMCA1 is shown to be present in the hSCT homogenate. However, the membrane fractions did not show any PMCA1 labeling. Our results must be taken into account in order to propose a new model for the transport of calcium across the hSCT.

The European Physical Journal Plus

Violeta Parra’s visual art is characterized by the integration of the popular Chilean artist’s cr... more Violeta Parra’s visual art is characterized by the integration of the popular Chilean artist’s craftsmanship, her field research, the role of women, poverty and injustice, as well as the use of everyday and modern art materials. Today, fifty years after her passing, Parra’s creations are still being debated on the grounds of a solid narrative that supports the current socio-political discussion of the Chilean and Latin American scenario, for which she has earned a fundamental place in the collective memory. “Justice” (1964, 149.5×109.5 cm) is an oil painting on burlap canvas from the collection of the “Museo Violeta Parra” (Violeta Parra Museum). For the first time, the recent conservation treatment of the painting has allowed the development of a scientific multi-analytical approach. This research aimed to study the color palette and understand the studio practice used by the artist in the creation of the oil painting. The scientific strategy included visual documentation, canvas characterization, noninvasive portable X-ray fluorescence spectroscopy (pXRF) to determine elemental composition, and vibrational spectroscopy analysis to identify pigments. In addition, a stratigraphic study was conducted to understand the painting technique used by Parra. However, due to the rich elemental composition found in the blue areas, consistent with the predominance of this color in the composition of the painting, a chemometric analysis was performed that allowed the identification of five characteristic elements: iron (Fe), cobalt (Co), manganese (Mn), chromium (Cr) and copper (Cu). By using Raman spectrometry and attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) analysis, the blue pigments were later identified as ultramarine blue, copper phthalocyanine blue, anthraquinone blue, and manganese blue. In contrast, no specific pigments could be identified to explain the systematic appearance of cobalt and iron. Since commercial production of manganese blue was limited to a narrow time frame, its identification could be further used as a marker for Parra’s color palette. Furthermore, the findings of the stratigraphic study showed that the artist made an overall application of a white ground layer, used a block distribution of underlying colors, and suggested the application of a varnish. Results correlated with previous documentation about Parra paying close attention to the facial expressions of the figures in her oil paintings, which is consistent with the application of multiple pictorial layers using a wet-on-wet painting technique. Due to the lack of evidence or studies on the subject, this research represents the first scientific milestone on the studio practice and use of materials in Parra’s visual artwork.

European Physical Journal Plus, 2023

Violeta Parra’s visual art is characterized by the integration of the popular Chilean artist’s cr... more Violeta Parra’s visual art is characterized by the integration of the popular Chilean artist’s craftsmanship, her field research, the role of women, poverty and injustice, as well as the use of everyday and modern art materials. Today, fifty years after her passing, Parra’s creations are still being debated on the grounds of a solid narrative that supports the current socio-political discussion of the Chilean and Latin American scenario, for which she has earned a fundamental place in the collective memory. “Justice” (1964, 149.5×109.5 cm) is an oil painting on burlap canvas from the collection of the “Museo Violeta Parra” (Violeta Parra Museum). For the first time, the recent conservation treatment of the painting has allowed the development of a scientific multi-analytical approach.
This research aimed to study the color palette and understand the studio practice used by the artist in the creation of the oil painting. The scientific strategy included visual documentation, canvas characterization, noninvasive portable X-ray fluorescence spectroscopy (pXRF) to determine elemental composition, and vibrational spectroscopy analysis to identify pigments. In addition, a stratigraphic study was conducted to understand the painting technique used by Parra. However, due to the rich elemental composition found in the blue areas, consistent with the predominance of this color in the composition of the painting, a chemometric analysis was performed that allowed the identification of five characteristic elements: iron (Fe), cobalt (Co), manganese (Mn), chromium (Cr) and copper (Cu). By using Raman spectrometry and attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) analysis, the blue pigments were later identified as ultramarine blue, copper phthalocyanine blue, anthraquinone blue, and manganese blue.
In contrast, no specific pigments could be identified to explain the systematic appearance of cobalt and iron. Since commercial
production of manganese blue was limited to a narrow time frame, its identification could be further used as a marker for Parra’s color palette. Furthermore, the findings of the stratigraphic study showed that the artist made an overall application of a white ground layer, used a block distribution of underlying colors, and suggested the application of a varnish. Results correlated with previous documentation about Parra paying close attention to the facial expressions of the figures in her oil paintings, which is consistent with the application of multiple pictorial layers using a wet-on-wet painting technique. Due to the lack of evidence or studies on the subject, this research represents the first scientific milestone on the studio practice and use of materials in Parra’s visual artwork.

La consulta d'aquesta tesi queda condicionada a l'acceptació de les següents condicions d'ús: La ... more La consulta d'aquesta tesi queda condicionada a l'acceptació de les següents condicions d'ús: La difusió d'aquesta tesi per mitjà del servei TDX (www.tdx.cat) i a través del Dipòsit Digital de la UB (diposit.ub.edu) ha estat autoritzada pels titulars dels drets de propietat intel•lectual únicament per a usos privats emmarcats en activitats d'investigació i docència. No s'autoritza la seva reproducció amb finalitats de lucre ni la seva difusió i posada a disposició des d'un lloc aliè al servei TDX ni al Dipòsit Digital de la UB. No s'autoritza la presentació del seu contingut en una finestra o marc aliè a TDX o al Dipòsit Digital de la UB (framing). Aquesta reserva de drets afecta tant al resum de presentació de la tesi com als seus continguts. En la utilització o cita de parts de la tesi és obligat indicar el nom de la persona autora. ADVERTENCIA. La consulta de esta tesis queda condicionada a la aceptación de las siguientes condiciones de uso: La difusión de esta tesis por medio del servicio TDR (www.tdx.cat) y a través del Repositorio Digital de la UB (diposit.ub.edu) ha sido autorizada por los titulares de los derechos de propiedad intelectual únicamente para usos privados enmarcados en actividades de investigación y docencia. No se autoriza su reproducción con finalidades de lucro ni su difusión y puesta a disposición desde un sitio ajeno al servicio TDR o al Repositorio Digital de la UB. No se autoriza la presentación de su contenido en una ventana o marco ajeno a TDR o al Repositorio Digital de la UB (framing). Esta reserva de derechos afecta tanto al resumen de presentación de la tesis como a sus contenidos. En la utilización o cita de

Los Centros de Detención, Tortura y Exterminio (CDTyE), se presentan en la actualidad, en su cali... more Los Centros de Detención, Tortura y Exterminio (CDTyE), se presentan en la actualidad, en su calidad de Sitios de Memorias, como lugares donde la materialidad y sus transformaciones, constituyen elementos que dialogan en el presente con el pasado traumático. En ese sentido los inmuebles son contenedores de evidencia, y por ende su investigación, desde una aproximación arqueológica y de conservación, aporta información útil para los procesos de verdad, justicia y memoria. El objetivo de este trabajo es presentar, a partir de una metodología participativa e interdisciplinaria, una serie de técnicas adoptadas de la arqueometría y la arqueología de la arquitectura, para apoyar el estudio de huellas y evidencias en Sitios de memoria.Clandestine centers for detention, torture and extermination, understood as sites of memory, are currently presented as places where materiality and its tr...

Biochemical and Biophysical Research Communications, 2012

The H syndrome (OMIM 612391) is an autosomal recessive disorder characterized by hyperpigmentatio... more The H syndrome (OMIM 612391) is an autosomal recessive disorder characterized by hyperpigmentation, hypertrichosis, histiocytosis and short stature. It is caused by mutations in the SLC29A3 gene, which encodes for the equilibrative nucleoside transporter 3 protein (ENT3), of still uncertain subcellular localisation. Here we report a new case of H syndrome with the novel mutation c.243delA, which has been concomitantly described by others [A. Bolze, A. Abhyankar, A.V. Grant, B. Patel, R. Yadav, M. Byun, D. Caillez, J.F. Emile, M. Pastor-Anglada, L. Abel, A. Puel, R. Govindarajan, L. de Pontual, J.L. Casanova, A mild form of SLC29A3 disorder: a frameshift deletion leads to the paradoxical translation of an otherwise noncoding mRNA splice variant, PLoS ONE 7 (2012) e29708]. Patient-derived primary skin fibroblasts and B-lymphoblastoid cell lines (B-LCL) were obtained and, although no differences were found in mRNA levels of ENT3, a significant increase in plasma membrane equilibrative transport activity was found in fibroblasts from the patient. Loss of function of key proteins implicated in nucleoside metabolism can lead to mitochondrial DNA (mtDNA) depletion syndromes (MDS). Measurement of respiratory chain complex activity revealed that mitochondrial function was unaltered. Neither fibroblasts nor B-LCL showed mtDNA depletion when compared with controls. Fibroblasts and B-LCL from the patient were not particularly protected when mitochondrial damage was induced using nucleoside-derived drugs susceptible to being transported by ENT3. Analysis of mtDNA amounts in tissues obtained at autopsy proved inconclusive with respect to mitochondrial involvement in the pathogenesis of this syndrome. Overall, the data do not support the inclusion of H syndrome among the MDS and these findings are compatible with its recent inclusion among the lysosomal storage diseases.

The plasma membrane distribution and related biological activity of nucleoside transporter protei... more The plasma membrane distribution and related biological activity of nucleoside transporter proteins (NT) have been investigated in human syncytiotrophoblast from term placenta using a variety of approaches, including nucleoside uptake measurements into vesicles from selected plasma membrane domains, NT immunohistochemistry and subcellular localization (basal, heavy and light apical membranes as well as raft enriched membranes from the apical domain). Conversely to other epithelia, we have identified the high-affinity pyrimidine-preferring concentrative nucleoside transporter hCNT1 as the only hCNT-type protein expressed at both the basal and apical membranes of this epithelium. hCNT1 localization in lipid rafts is also dependent upon its subcellular localization in the apical plasma membrane, suggesting a complex cellular and regional expression. Overall, this favours the view that the placenta is a pyrimidine-preferring nucleoside sink from both maternal and fetal sides and hCNT1 plays a major role in promoting pyrimidine salvage and placental growth. This finding may be of pharmacological relevance, because hCNT1 is known to interact with anticancer nucleoside-derived drugs and other molecules, such as nicotine and caffeine, for which a great variety of harmful effects on placental and fetal development, including IUGR, have been reported.

The plasma membrane distribution and related biological ac-tivity of nucleoside transporter prote... more The plasma membrane distribution and related biological ac-tivity of nucleoside transporter proteins (NTs) were investigated in human syncytiotrophoblast from term placenta using a vari-ety of approaches, including nucleoside uptake measurements into vesicles from selected plasma membrane domains, NT immunohistochemistry, and subcellular localization (basal, heavy, and light apical membranes as well as raft-enriched membranes from the apical domain). In contrast with other epithelia, in this epithelium, we have identified the high-affinity pyrimidine-preferring human concentrative nucleoside trans-porter (hCNT) 1 as the only hCNT-type protein expressed at both the basal and apical membranes. hCNT1 localization in lipid rafts is also dependent on its subcellular localization in the apical plasma membrane, suggesting a complex cellular and regional expression. Overall, this result favors the view that the placenta is a pyrimidine-preferring nucleoside sink from both maternal and fetal...

Journal of Hepatology, 2011

POSTERS immunoprecipitations, immunoblot, immunofluorescence) to investigate the functions of AGR... more POSTERS immunoprecipitations, immunoblot, immunofluorescence) to investigate the functions of AGR2 in the ER. Results: We show that AGR2 localizes to the lumen of the ER, using immunofluorescence microscopy, and that AGR2 associates to ER membrane-bound ribosomes through nascent polypeptides, using ribosome pull-down strategies. In addition, we demonstrate that AGR2 expression is up-regulated upon ER stress through the Unfolded Protein Response. Finally, we show that AGR2 participates to productive protein folding in the ER lumen using 35 S-Methionine pulse-chase experiments followed by immunoprecipitation of selected AGR2 substrates in cells knocked-down or not for AGR2 and covalently binds to its substrates through mixed disulfide bonds. This led us to postulate that AGR2 might be involved in protecting free cysteines from engaging too prematurely in disulfide bridges, events important for optimal maturation of slowly folding proteins such as mucins. Conclusion: Our study shows that expression of AGR2 is a phenotypic feature of all ECC and mucus-secreting ICC. This observation may reflect an adaptive mechanism of CC tumor cells to cope with increased secretory protein load (in particular mucins) and challenging environments (such as hypoxia).

Journal of Hepatology, 2012

Journal of hepatology, 2014

Both hepatocytes and cholangiocytes release ATP into the bile, where it acts as a potent autocrin... more Both hepatocytes and cholangiocytes release ATP into the bile, where it acts as a potent autocrine/paracrine stimulus that activates biliary secretory mechanisms. ATP is known to be metabolized into multiple breakdown products, ultimately yielding adenosine. However, the elements implicated in the adenosine-dependent purinergic regulation of cholangiocytes are not known. Normal rat cholangiocytes (NRCs) were used to study the expression of adenosine receptors and transporters and their functional interactions at the apical and basolateral membrane domains of polarized cholangiocytes. We found that: (1) cholangiocytes exclusively express two concentrative nucleoside transporters (CNT) known to be efficient adenosine carriers: CNT3, located at the apical membrane, and CNT2, located at apical and basolateral membrane domains; (2) in both domains, NRCs also express the high affinity adenosine receptor A2A, which modulated the activity of apical CNT3 in a domain-specific manner; (3) the ...

Molecular Pharmacology, 2011

The plasma membrane distribution and related biological activity of nucleoside transporter protei... more The plasma membrane distribution and related biological activity of nucleoside transporter proteins (NTs) were investigated in human syncytiotrophoblast from term placenta using a variety of approaches, including nucleoside uptake measurements into vesicles from selected plasma membrane domains, NT immunohistochemistry, and subcellular localization (basal, heavy, and light apical membranes as well as raft-enriched membranes from the apical domain). In contrast with other epithelia, in this epithelium, we have identified the high-affinity pyrimidine-preferring human concentrative nucleoside transporter (hCNT) 1 as the only hCNT-type protein expressed at both the basal and apical membranes. hCNT1 localization in lipid rafts is also dependent on its subcellular localization in the apical plasma membrane, suggesting a complex cellular and regional expression. Overall, this result favors the view that the placenta is a pyrimidine-preferring nucleoside sink from both maternal and fetal sides, and hCNT1 plays a major role in promoting pyrimidine salvage and placental growth. This finding may be of pharmacological relevance, because hCNT1 is known to interact with anticancer nucleoside-derived drugs and other molecules, such as nicotine and caffeine, for which a great variety of harmful effects on placental and fetal development, including intrauterine growth retardation, have been reported. Innovación [Grant AP2003-3938] (to E.E.-M.). G.R. and M.P.-A. contributed equally to this work.

The Journal of Membrane Biology, 2011

Intrauterine growth restriction (IUGR) and preeclampsia (PE) are leading causes of perinatal and ... more Intrauterine growth restriction (IUGR) and preeclampsia (PE) are leading causes of perinatal and maternal morbidity and mortality. Previously we reported the expression of lipid rafts in classical microvillous membrane (MVM) and light microvillous membrane (LMVM), two subdomains in apical membrane from the human placental syncytiotrophoblast (hSTB), which constitute the epithelium responsible for maternal-fetal transport. Here the aim was to study the raft and cytoskeletal proteins from PE and IUGR. Microdomains from MVM and LMVM were tested with raft markers (placental alkaline phosphatase, lipid ganglioside, and annexin 2) and a nonraft marker (hTf-R). No changes were detected with those markers in whole purified apical membranes in normal, PE, and IUGR pregnancies; however, their patterns of distribution in lipid rafts were different in PE and IUGR. Cholesterol depletion modified their segregation, confirming their presence in lipid rafts, although unlike normal placenta, in these pathologies there is only one type of microdomain. Additionally, the cytoskeleton proteins actin, ezrin, and cytokeratin-7 showed clear differences between normal and pathological membranes. Cytokeratin-7 expression decreased to 50% in PE, and the distribution between LMVM and MVM (*43 and 57%, respectively) changed in both PE and IUGR, in contrast with the asymmetrical enrichment obtained in normal LMVM (*62%). In conclusion, lipid rafts from IUGR and PE have different features compared to rafts from normal placentae, and this is associated with alterations in the expression and distribution of cytoskeletal proteins.

Biochemical and Biophysical Research Communications, 2012

The H syndrome (OMIM 612391) is an autosomal recessive disorder characterized by hyperpigmentatio... more The H syndrome (OMIM 612391) is an autosomal recessive disorder characterized by hyperpigmentation, hypertrichosis, histiocytosis and short stature. It is caused by mutations in the SLC29A3 gene, which encodes for the equilibrative nucleoside transporter 3 protein (ENT3), of still uncertain subcellular localisation. Here we report a new case of H syndrome with the novel mutation c.243delA, which has been concomitantly described by others [A. Bolze, A. Abhyankar, A.V. Grant, B. Patel, R. Yadav, M. Byun, D. Caillez, J.F. Emile, M. Pastor-Anglada, L. Abel, A. Puel, R. Govindarajan, L. de Pontual, J.L. Casanova, A mild form of SLC29A3 disorder: a frameshift deletion leads to the paradoxical translation of an otherwise noncoding mRNA splice variant, PLoS ONE 7 (2012) e29708]. Patient-derived primary skin fibroblasts and B-lymphoblastoid cell lines (B-LCL) were obtained and, although no differences were found in mRNA levels of ENT3, a significant increase in plasma membrane equilibrative transport activity was found in fibroblasts from the patient. Loss of function of key proteins implicated in nucleoside metabolism can lead to mitochondrial DNA (mtDNA) depletion syndromes (MDS). Measurement of respiratory chain complex activity revealed that mitochondrial function was unaltered. Neither fibroblasts nor B-LCL showed mtDNA depletion when compared with controls. Fibroblasts and B-LCL from the patient were not particularly protected when mitochondrial damage was induced using nucleoside-derived drugs susceptible to being transported by ENT3. Analysis of mtDNA amounts in tissues obtained at autopsy proved inconclusive with respect to mitochondrial involvement in the pathogenesis of this syndrome. Overall, the data do not support the inclusion of H syndrome among the MDS and these findings are compatible with its recent inclusion among the lysosomal storage diseases.

Journal of Membrane Biology, 2008

We report on the characteristics of raft domains in the apical membrane from human placental sync... more We report on the characteristics of raft domains in the apical membrane from human placental syncytiotrophoblast (hSTB), an epithelium responsible for maternal–fetal exchange. Previously, we described two isolated fractions of the hSTB apical membrane: a classical microvillous membrane (MVM) and a light microvillous membrane (LMVM). Detergent-resistant microdomains (DRMs) from MVM and LMVM were prepared with Triton X-100 followed by flotation in a sucrose gradient and tested by Western and dot blot with raft markers (placental alkaline phosphatase, lipid ganglioside, annexin 2) and transferrin receptor as a nonraft marker. DRMs from both fractions showed a consistent peak for these markers, except that the DRMs from MVM had no annexin 2 mark. Cholesterol depletion modified the segregation in both groups of DRMs. Our results show two distinguishable lipid raft subsets from MVM and LMVM. Additionally, we found significant differences between MVM and LMVM in cholesterol content and in expression of cytoskeletal proteins. MVM is enriched in ezrin and β-actin; in contrast, cholesterol and cytokeratin-7 are more abundant in LMVM. These differences may explain the distinct properties of the lipid raft subtypes.

It is known that human syncytiotrophoblast (hSCT) actively transports more than 80% of the Ca 2þ ... more It is known that human syncytiotrophoblast (hSCT) actively transports more than 80% of the Ca 2þ that goes from maternal to fetal circulation. Transepithelial transport of Ca 2þ is carried out through channels, transporters and exchangers located in both microvillous (MVM) and basal (BM) plasma membranes. The plasma membrane Ca-ATPase (PMCA) is the most important mechanism of Ca 2þ homeostasis control in the human placenta. In this work, we reexamined the distribution of PMCA in isolated hSCT of term placenta. The PMCA activity was determined in isolated hSCT plasma membranes. A partial characterization of the PMCA activity was performed, including an evaluation of the sensitivity of this enzyme to an in vitro induced lipid peroxidation. Expression of the PMCA in hSCT plasma membranes and tissue sections was investigated using Western blots and immunohistochemistry, respectively. Our study demonstrates, for the first time, a correlation between the activity and structural distribution of PMCA in both MVM and BM of hSCT. It also demonstrates a higher PMCA activity and expression in MVM as compared to BM. Finally, PMCA4 seems to be preferentially distributed in both hSCT plasma membranes, while PMCA1 is shown to be present in the hSCT homogenate. However, the membrane fractions did not show any PMCA1 labeling. Our results must be taken into account in order to propose a new model for the transport of calcium across the hSCT.

The European Physical Journal Plus

Violeta Parra’s visual art is characterized by the integration of the popular Chilean artist’s cr... more Violeta Parra’s visual art is characterized by the integration of the popular Chilean artist’s craftsmanship, her field research, the role of women, poverty and injustice, as well as the use of everyday and modern art materials. Today, fifty years after her passing, Parra’s creations are still being debated on the grounds of a solid narrative that supports the current socio-political discussion of the Chilean and Latin American scenario, for which she has earned a fundamental place in the collective memory. “Justice” (1964, 149.5×109.5 cm) is an oil painting on burlap canvas from the collection of the “Museo Violeta Parra” (Violeta Parra Museum). For the first time, the recent conservation treatment of the painting has allowed the development of a scientific multi-analytical approach. This research aimed to study the color palette and understand the studio practice used by the artist in the creation of the oil painting. The scientific strategy included visual documentation, canvas characterization, noninvasive portable X-ray fluorescence spectroscopy (pXRF) to determine elemental composition, and vibrational spectroscopy analysis to identify pigments. In addition, a stratigraphic study was conducted to understand the painting technique used by Parra. However, due to the rich elemental composition found in the blue areas, consistent with the predominance of this color in the composition of the painting, a chemometric analysis was performed that allowed the identification of five characteristic elements: iron (Fe), cobalt (Co), manganese (Mn), chromium (Cr) and copper (Cu). By using Raman spectrometry and attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) analysis, the blue pigments were later identified as ultramarine blue, copper phthalocyanine blue, anthraquinone blue, and manganese blue. In contrast, no specific pigments could be identified to explain the systematic appearance of cobalt and iron. Since commercial production of manganese blue was limited to a narrow time frame, its identification could be further used as a marker for Parra’s color palette. Furthermore, the findings of the stratigraphic study showed that the artist made an overall application of a white ground layer, used a block distribution of underlying colors, and suggested the application of a varnish. Results correlated with previous documentation about Parra paying close attention to the facial expressions of the figures in her oil paintings, which is consistent with the application of multiple pictorial layers using a wet-on-wet painting technique. Due to the lack of evidence or studies on the subject, this research represents the first scientific milestone on the studio practice and use of materials in Parra’s visual artwork.

European Physical Journal Plus, 2023

Violeta Parra’s visual art is characterized by the integration of the popular Chilean artist’s cr... more Violeta Parra’s visual art is characterized by the integration of the popular Chilean artist’s craftsmanship, her field research, the role of women, poverty and injustice, as well as the use of everyday and modern art materials. Today, fifty years after her passing, Parra’s creations are still being debated on the grounds of a solid narrative that supports the current socio-political discussion of the Chilean and Latin American scenario, for which she has earned a fundamental place in the collective memory. “Justice” (1964, 149.5×109.5 cm) is an oil painting on burlap canvas from the collection of the “Museo Violeta Parra” (Violeta Parra Museum). For the first time, the recent conservation treatment of the painting has allowed the development of a scientific multi-analytical approach.
This research aimed to study the color palette and understand the studio practice used by the artist in the creation of the oil painting. The scientific strategy included visual documentation, canvas characterization, noninvasive portable X-ray fluorescence spectroscopy (pXRF) to determine elemental composition, and vibrational spectroscopy analysis to identify pigments. In addition, a stratigraphic study was conducted to understand the painting technique used by Parra. However, due to the rich elemental composition found in the blue areas, consistent with the predominance of this color in the composition of the painting, a chemometric analysis was performed that allowed the identification of five characteristic elements: iron (Fe), cobalt (Co), manganese (Mn), chromium (Cr) and copper (Cu). By using Raman spectrometry and attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) analysis, the blue pigments were later identified as ultramarine blue, copper phthalocyanine blue, anthraquinone blue, and manganese blue.
In contrast, no specific pigments could be identified to explain the systematic appearance of cobalt and iron. Since commercial
production of manganese blue was limited to a narrow time frame, its identification could be further used as a marker for Parra’s color palette. Furthermore, the findings of the stratigraphic study showed that the artist made an overall application of a white ground layer, used a block distribution of underlying colors, and suggested the application of a varnish. Results correlated with previous documentation about Parra paying close attention to the facial expressions of the figures in her oil paintings, which is consistent with the application of multiple pictorial layers using a wet-on-wet painting technique. Due to the lack of evidence or studies on the subject, this research represents the first scientific milestone on the studio practice and use of materials in Parra’s visual artwork.

La consulta d'aquesta tesi queda condicionada a l'acceptació de les següents condicions d'ús: La ... more La consulta d'aquesta tesi queda condicionada a l'acceptació de les següents condicions d'ús: La difusió d'aquesta tesi per mitjà del servei TDX (www.tdx.cat) i a través del Dipòsit Digital de la UB (diposit.ub.edu) ha estat autoritzada pels titulars dels drets de propietat intel•lectual únicament per a usos privats emmarcats en activitats d'investigació i docència. No s'autoritza la seva reproducció amb finalitats de lucre ni la seva difusió i posada a disposició des d'un lloc aliè al servei TDX ni al Dipòsit Digital de la UB. No s'autoritza la presentació del seu contingut en una finestra o marc aliè a TDX o al Dipòsit Digital de la UB (framing). Aquesta reserva de drets afecta tant al resum de presentació de la tesi com als seus continguts. En la utilització o cita de parts de la tesi és obligat indicar el nom de la persona autora. ADVERTENCIA. La consulta de esta tesis queda condicionada a la aceptación de las siguientes condiciones de uso: La difusión de esta tesis por medio del servicio TDR (www.tdx.cat) y a través del Repositorio Digital de la UB (diposit.ub.edu) ha sido autorizada por los titulares de los derechos de propiedad intelectual únicamente para usos privados enmarcados en actividades de investigación y docencia. No se autoriza su reproducción con finalidades de lucro ni su difusión y puesta a disposición desde un sitio ajeno al servicio TDR o al Repositorio Digital de la UB. No se autoriza la presentación de su contenido en una ventana o marco ajeno a TDR o al Repositorio Digital de la UB (framing). Esta reserva de derechos afecta tanto al resumen de presentación de la tesis como a sus contenidos. En la utilización o cita de

Los Centros de Detención, Tortura y Exterminio (CDTyE), se presentan en la actualidad, en su cali... more Los Centros de Detención, Tortura y Exterminio (CDTyE), se presentan en la actualidad, en su calidad de Sitios de Memorias, como lugares donde la materialidad y sus transformaciones, constituyen elementos que dialogan en el presente con el pasado traumático. En ese sentido los inmuebles son contenedores de evidencia, y por ende su investigación, desde una aproximación arqueológica y de conservación, aporta información útil para los procesos de verdad, justicia y memoria. El objetivo de este trabajo es presentar, a partir de una metodología participativa e interdisciplinaria, una serie de técnicas adoptadas de la arqueometría y la arqueología de la arquitectura, para apoyar el estudio de huellas y evidencias en Sitios de memoria.Clandestine centers for detention, torture and extermination, understood as sites of memory, are currently presented as places where materiality and its tr...

Biochemical and Biophysical Research Communications, 2012

The H syndrome (OMIM 612391) is an autosomal recessive disorder characterized by hyperpigmentatio... more The H syndrome (OMIM 612391) is an autosomal recessive disorder characterized by hyperpigmentation, hypertrichosis, histiocytosis and short stature. It is caused by mutations in the SLC29A3 gene, which encodes for the equilibrative nucleoside transporter 3 protein (ENT3), of still uncertain subcellular localisation. Here we report a new case of H syndrome with the novel mutation c.243delA, which has been concomitantly described by others [A. Bolze, A. Abhyankar, A.V. Grant, B. Patel, R. Yadav, M. Byun, D. Caillez, J.F. Emile, M. Pastor-Anglada, L. Abel, A. Puel, R. Govindarajan, L. de Pontual, J.L. Casanova, A mild form of SLC29A3 disorder: a frameshift deletion leads to the paradoxical translation of an otherwise noncoding mRNA splice variant, PLoS ONE 7 (2012) e29708]. Patient-derived primary skin fibroblasts and B-lymphoblastoid cell lines (B-LCL) were obtained and, although no differences were found in mRNA levels of ENT3, a significant increase in plasma membrane equilibrative transport activity was found in fibroblasts from the patient. Loss of function of key proteins implicated in nucleoside metabolism can lead to mitochondrial DNA (mtDNA) depletion syndromes (MDS). Measurement of respiratory chain complex activity revealed that mitochondrial function was unaltered. Neither fibroblasts nor B-LCL showed mtDNA depletion when compared with controls. Fibroblasts and B-LCL from the patient were not particularly protected when mitochondrial damage was induced using nucleoside-derived drugs susceptible to being transported by ENT3. Analysis of mtDNA amounts in tissues obtained at autopsy proved inconclusive with respect to mitochondrial involvement in the pathogenesis of this syndrome. Overall, the data do not support the inclusion of H syndrome among the MDS and these findings are compatible with its recent inclusion among the lysosomal storage diseases.

The plasma membrane distribution and related biological activity of nucleoside transporter protei... more The plasma membrane distribution and related biological activity of nucleoside transporter proteins (NT) have been investigated in human syncytiotrophoblast from term placenta using a variety of approaches, including nucleoside uptake measurements into vesicles from selected plasma membrane domains, NT immunohistochemistry and subcellular localization (basal, heavy and light apical membranes as well as raft enriched membranes from the apical domain). Conversely to other epithelia, we have identified the high-affinity pyrimidine-preferring concentrative nucleoside transporter hCNT1 as the only hCNT-type protein expressed at both the basal and apical membranes of this epithelium. hCNT1 localization in lipid rafts is also dependent upon its subcellular localization in the apical plasma membrane, suggesting a complex cellular and regional expression. Overall, this favours the view that the placenta is a pyrimidine-preferring nucleoside sink from both maternal and fetal sides and hCNT1 plays a major role in promoting pyrimidine salvage and placental growth. This finding may be of pharmacological relevance, because hCNT1 is known to interact with anticancer nucleoside-derived drugs and other molecules, such as nicotine and caffeine, for which a great variety of harmful effects on placental and fetal development, including IUGR, have been reported.

The plasma membrane distribution and related biological ac-tivity of nucleoside transporter prote... more The plasma membrane distribution and related biological ac-tivity of nucleoside transporter proteins (NTs) were investigated in human syncytiotrophoblast from term placenta using a vari-ety of approaches, including nucleoside uptake measurements into vesicles from selected plasma membrane domains, NT immunohistochemistry, and subcellular localization (basal, heavy, and light apical membranes as well as raft-enriched membranes from the apical domain). In contrast with other epithelia, in this epithelium, we have identified the high-affinity pyrimidine-preferring human concentrative nucleoside trans-porter (hCNT) 1 as the only hCNT-type protein expressed at both the basal and apical membranes. hCNT1 localization in lipid rafts is also dependent on its subcellular localization in the apical plasma membrane, suggesting a complex cellular and regional expression. Overall, this result favors the view that the placenta is a pyrimidine-preferring nucleoside sink from both maternal and fetal...

Journal of Hepatology, 2011

POSTERS immunoprecipitations, immunoblot, immunofluorescence) to investigate the functions of AGR... more POSTERS immunoprecipitations, immunoblot, immunofluorescence) to investigate the functions of AGR2 in the ER. Results: We show that AGR2 localizes to the lumen of the ER, using immunofluorescence microscopy, and that AGR2 associates to ER membrane-bound ribosomes through nascent polypeptides, using ribosome pull-down strategies. In addition, we demonstrate that AGR2 expression is up-regulated upon ER stress through the Unfolded Protein Response. Finally, we show that AGR2 participates to productive protein folding in the ER lumen using 35 S-Methionine pulse-chase experiments followed by immunoprecipitation of selected AGR2 substrates in cells knocked-down or not for AGR2 and covalently binds to its substrates through mixed disulfide bonds. This led us to postulate that AGR2 might be involved in protecting free cysteines from engaging too prematurely in disulfide bridges, events important for optimal maturation of slowly folding proteins such as mucins. Conclusion: Our study shows that expression of AGR2 is a phenotypic feature of all ECC and mucus-secreting ICC. This observation may reflect an adaptive mechanism of CC tumor cells to cope with increased secretory protein load (in particular mucins) and challenging environments (such as hypoxia).

Journal of Hepatology, 2012

Journal of hepatology, 2014

Both hepatocytes and cholangiocytes release ATP into the bile, where it acts as a potent autocrin... more Both hepatocytes and cholangiocytes release ATP into the bile, where it acts as a potent autocrine/paracrine stimulus that activates biliary secretory mechanisms. ATP is known to be metabolized into multiple breakdown products, ultimately yielding adenosine. However, the elements implicated in the adenosine-dependent purinergic regulation of cholangiocytes are not known. Normal rat cholangiocytes (NRCs) were used to study the expression of adenosine receptors and transporters and their functional interactions at the apical and basolateral membrane domains of polarized cholangiocytes. We found that: (1) cholangiocytes exclusively express two concentrative nucleoside transporters (CNT) known to be efficient adenosine carriers: CNT3, located at the apical membrane, and CNT2, located at apical and basolateral membrane domains; (2) in both domains, NRCs also express the high affinity adenosine receptor A2A, which modulated the activity of apical CNT3 in a domain-specific manner; (3) the ...

Molecular Pharmacology, 2011

The plasma membrane distribution and related biological activity of nucleoside transporter protei... more The plasma membrane distribution and related biological activity of nucleoside transporter proteins (NTs) were investigated in human syncytiotrophoblast from term placenta using a variety of approaches, including nucleoside uptake measurements into vesicles from selected plasma membrane domains, NT immunohistochemistry, and subcellular localization (basal, heavy, and light apical membranes as well as raft-enriched membranes from the apical domain). In contrast with other epithelia, in this epithelium, we have identified the high-affinity pyrimidine-preferring human concentrative nucleoside transporter (hCNT) 1 as the only hCNT-type protein expressed at both the basal and apical membranes. hCNT1 localization in lipid rafts is also dependent on its subcellular localization in the apical plasma membrane, suggesting a complex cellular and regional expression. Overall, this result favors the view that the placenta is a pyrimidine-preferring nucleoside sink from both maternal and fetal sides, and hCNT1 plays a major role in promoting pyrimidine salvage and placental growth. This finding may be of pharmacological relevance, because hCNT1 is known to interact with anticancer nucleoside-derived drugs and other molecules, such as nicotine and caffeine, for which a great variety of harmful effects on placental and fetal development, including intrauterine growth retardation, have been reported. Innovación [Grant AP2003-3938] (to E.E.-M.). G.R. and M.P.-A. contributed equally to this work.

The Journal of Membrane Biology, 2011

Intrauterine growth restriction (IUGR) and preeclampsia (PE) are leading causes of perinatal and ... more Intrauterine growth restriction (IUGR) and preeclampsia (PE) are leading causes of perinatal and maternal morbidity and mortality. Previously we reported the expression of lipid rafts in classical microvillous membrane (MVM) and light microvillous membrane (LMVM), two subdomains in apical membrane from the human placental syncytiotrophoblast (hSTB), which constitute the epithelium responsible for maternal-fetal transport. Here the aim was to study the raft and cytoskeletal proteins from PE and IUGR. Microdomains from MVM and LMVM were tested with raft markers (placental alkaline phosphatase, lipid ganglioside, and annexin 2) and a nonraft marker (hTf-R). No changes were detected with those markers in whole purified apical membranes in normal, PE, and IUGR pregnancies; however, their patterns of distribution in lipid rafts were different in PE and IUGR. Cholesterol depletion modified their segregation, confirming their presence in lipid rafts, although unlike normal placenta, in these pathologies there is only one type of microdomain. Additionally, the cytoskeleton proteins actin, ezrin, and cytokeratin-7 showed clear differences between normal and pathological membranes. Cytokeratin-7 expression decreased to 50% in PE, and the distribution between LMVM and MVM (*43 and 57%, respectively) changed in both PE and IUGR, in contrast with the asymmetrical enrichment obtained in normal LMVM (*62%). In conclusion, lipid rafts from IUGR and PE have different features compared to rafts from normal placentae, and this is associated with alterations in the expression and distribution of cytoskeletal proteins.

Biochemical and Biophysical Research Communications, 2012

The H syndrome (OMIM 612391) is an autosomal recessive disorder characterized by hyperpigmentatio... more The H syndrome (OMIM 612391) is an autosomal recessive disorder characterized by hyperpigmentation, hypertrichosis, histiocytosis and short stature. It is caused by mutations in the SLC29A3 gene, which encodes for the equilibrative nucleoside transporter 3 protein (ENT3), of still uncertain subcellular localisation. Here we report a new case of H syndrome with the novel mutation c.243delA, which has been concomitantly described by others [A. Bolze, A. Abhyankar, A.V. Grant, B. Patel, R. Yadav, M. Byun, D. Caillez, J.F. Emile, M. Pastor-Anglada, L. Abel, A. Puel, R. Govindarajan, L. de Pontual, J.L. Casanova, A mild form of SLC29A3 disorder: a frameshift deletion leads to the paradoxical translation of an otherwise noncoding mRNA splice variant, PLoS ONE 7 (2012) e29708]. Patient-derived primary skin fibroblasts and B-lymphoblastoid cell lines (B-LCL) were obtained and, although no differences were found in mRNA levels of ENT3, a significant increase in plasma membrane equilibrative transport activity was found in fibroblasts from the patient. Loss of function of key proteins implicated in nucleoside metabolism can lead to mitochondrial DNA (mtDNA) depletion syndromes (MDS). Measurement of respiratory chain complex activity revealed that mitochondrial function was unaltered. Neither fibroblasts nor B-LCL showed mtDNA depletion when compared with controls. Fibroblasts and B-LCL from the patient were not particularly protected when mitochondrial damage was induced using nucleoside-derived drugs susceptible to being transported by ENT3. Analysis of mtDNA amounts in tissues obtained at autopsy proved inconclusive with respect to mitochondrial involvement in the pathogenesis of this syndrome. Overall, the data do not support the inclusion of H syndrome among the MDS and these findings are compatible with its recent inclusion among the lysosomal storage diseases.

Journal of Membrane Biology, 2008

We report on the characteristics of raft domains in the apical membrane from human placental sync... more We report on the characteristics of raft domains in the apical membrane from human placental syncytiotrophoblast (hSTB), an epithelium responsible for maternal–fetal exchange. Previously, we described two isolated fractions of the hSTB apical membrane: a classical microvillous membrane (MVM) and a light microvillous membrane (LMVM). Detergent-resistant microdomains (DRMs) from MVM and LMVM were prepared with Triton X-100 followed by flotation in a sucrose gradient and tested by Western and dot blot with raft markers (placental alkaline phosphatase, lipid ganglioside, annexin 2) and transferrin receptor as a nonraft marker. DRMs from both fractions showed a consistent peak for these markers, except that the DRMs from MVM had no annexin 2 mark. Cholesterol depletion modified the segregation in both groups of DRMs. Our results show two distinguishable lipid raft subsets from MVM and LMVM. Additionally, we found significant differences between MVM and LMVM in cholesterol content and in expression of cytoskeletal proteins. MVM is enriched in ezrin and β-actin; in contrast, cholesterol and cytokeratin-7 are more abundant in LMVM. These differences may explain the distinct properties of the lipid raft subtypes.