karina torres - Academia.edu (original) (raw)

Papers by karina torres

Dataismo, 2021

El presente estudio describe los niveles de inteligencia emocional en adolescentes de escuelas pú... more El presente estudio describe los niveles de inteligencia emocional en adolescentes de escuelas públicas. Dicha investigación presenta una metodología dada en Declaración PRISMA, que presenta información relevante e importante obtenida en diferentes bases de datos bibliográficas como Scopus, EBSCO y Springer dado en un tiempo final de un año y siete meses. El proceso de identificación, cribado, elegibilidad e inclusión se desarrolló en dos meses. De los 120 artículos de investigación que dio origen a la búsqueda científica, se eligieron 15 que ayudaron a establecer el objetivo planteado. Los criterios de incorporación como artículos de investigación, revisiones sistemáticas y estudios de caso; revisados por pares, relacionados o interrelacionados con la temática a la variable inteligencia emocional fueron pieza clave para la elaboración de la revisión sistemática. Los criterios de eliminación e indagación que no fueron elegidos y sujetos a una elaboración de trabajo presentaron defic...

Dataismo, 2021

El objetivo de esta revisión sistemática fue analizar el desarrollo de las habilidades sociales e... more El objetivo de esta revisión sistemática fue analizar el desarrollo de las habilidades sociales en los docentes del magisterio. El estudio se desarrolló siguiendo la metodología establecida en la declaración PRISMA, la información científica se recuperó principalmente de Ebsco, Scopus y Springer en un periodo de dos meses. El proceso de identificación, cribado, elegibilidad e inclusión se desarrolló en un mes. De los 134 estudios que arrojó la búsqueda especializada, solamente se incluyeron 15. Criterios de inclusión: artículos de investigación, revisiones sistemáticas y estudio de casos, relacionados con las palabras habilidades sociales, docentes, habilidades básicas, planificación, sentimientos. Criterios de exclusión: investigaciones con deficiencias metodológicas o que no tienen relación con el objetivo del estudio. Los resultados indican que el desarrollo de las habilidades sociales son determinantes en los docentes del magisterio para el logro de una mejor calidad de vida en ...

Presentaciones orales A low degranulation ability of activated CD8 + T cells is associated with t... more Presentaciones orales A low degranulation ability of activated CD8 + T cells is associated with the persistent systemic immune activation in HIV-infected patients, despite viral suppression induced by the anti-retroviral therapy

Viruses, Sep 7, 2018

The high levels of dengue-virus (DENV) seroprevalence in areas where the Zika virus (ZIKV) is cir... more The high levels of dengue-virus (DENV) seroprevalence in areas where the Zika virus (ZIKV) is circulating and the cross-reactivity between these two viruses have raised concerns on the risk of increased ZIKV disease severity for patients with a history of previous DENV infections. To determine the role of DENV preimmunity in ZIKV infection, we analyzed the T- and B-cell responses against ZIKV in donors with or without previous DENV infection. Using peripheral blood mononuclear cells (PBMCs) from donors living in an endemic area in Colombia, we have identified, by interferon (IFN)-γ enzyme-linked immunospot (ELISPOT) assay, most of the immunodominant ZIKV T-cell epitopes in the nonstructural (NS) proteins NS1, NS3, and NS5. Analyses of the T- and B-cell responses in the same donors revealed a stronger T-cell response against peptides conserved between DENV and ZIKV, with a higher level of ZIKV-neutralizing antibodies in DENV-immune donors in comparison with DENV-naïve donors. Strikin...

Neotropical Biodiversity, 2016

Examining dispersal is critical for understanding the diversity of Andean-centered plant lineages... more Examining dispersal is critical for understanding the diversity of Andean-centered plant lineages, like Burmeistera (Campanulaceae). One-third of its species present an unusual inflated berry. Unlike the bright colors of non-inflated fruits in the genus, these fruits are typically dull-green; however, the fact that the seeds are loosely held in the placenta and easily removed when touched seems to suggest adaptation to animal dispersal. We studied two inflated-baccate species, Burmeistera glabrata and B. borjensis, with the aim of testing the non-exclusive hypotheses that their seeds are dispersed by (1) small mammals, (2) slugs, or (3) adult flies that develop inside the fruits. In two sites in the Ecuadorian Andes, we performed observations at dusk and dawn to examine the fate of fruits and seeds; recording fruit fall, formation of holes in the fruits, and seed loss from the placenta. We documented fruit visitors with cameras, and surveyed unopened fruits for the presence of insect larvae and seed condition. Finally, we performed an experiment to examine the effect of holes and rain in germination, in order to evaluate if holes are required for seeds to leave the fruits and subsequently germinate. For both species, most fruits fell and decomposed beneath the mother plant. However, we found limited support for small mammal dispersal; videos and observations revealed that mice and squirrels are potential, but rare, seed dispersers. We found no evidence for slug or fly dispersal; fly larvae were common inside fruits, but acted exclusively as seed predators. Crickets often chewed holes in fruits on plants and on the ground. Holes did not have an effect on germination, which was induced only by rain. Hence, the majority of seeds end up under the mother plant, with rare but potentially important events of primary or secondary dispersal by small mammals. The combination of limited dispersal due to gravity and rare events of mammal dispersal may have played a critical role in the rapid diversification of Burmeistera.

Projektet handlar om att forbattra diabetikers livskvalitet genom att forska kring hur en framtid... more Projektet handlar om att forbattra diabetikers livskvalitet genom att forska kring hur en framtida insulinpump med integrerad blodsockermatare bor utformas for att tilltala anvandarna. Det syftar t ...

For many years, the United States has been known as the great “melting pot” with a mixture of peo... more For many years, the United States has been known as the great “melting pot” with a mixture of people representing different races and ethnicities that have come together to form one nation and one American identity. The American educational system has attempted to facilitate the creation of one national identity through the process of assimilation and through its insistence that

Molecular Reproduction and Development, 2011

The prevalence of spontaneous mutations increases with age in the male germline; consequently, ol... more The prevalence of spontaneous mutations increases with age in the male germline; consequently, older men have an increased risk of siring children with genetic disease due to de novo mutations. The lacI transgenic mouse can be used to study paternal age effects, and in this system, the prevalence of de novo mutations increases in the male germline at old ages. Mutagenesis is linked with DNA repair capacity, and base excision repair, which can ameliorate spontaneous DNA damage, decreases in nuclear extracts of spermatogenic cells from old mice. Mice heterozygous for a null allele of the Apex1 gene, which encodes apurinic/apyrimidinic endonuclease I (APEN), an essential base excision repair enzyme, display an accelerated increase in spontaneous germline mutagenesis early in life. Here, the consequences of lifelong reduction of APEN on genetic instability in the male germline were examined, for the first time, at middle and old ages. Mutation frequency increased earlier in spermatogenic cells from Apex1 +/− mice (by 6 months of age). Nuclear DNA damage increased with age in the spermatogenic lineage for both wild-type and Apex1 +/− mice. By old age, mutation frequencies were similar for wild-type and APEN-deficient mice. Mitochondrial genome repair also depends on APEN, and novel analysis of mitochondrial DNA damage revealed an increase in the Apex1 +/− spermatogenic cells by middle age. Thus, Apex1 heterozygosity results in accelerated damage to mitochondrial DNA and spontaneous mutagenesis, consistent with an essential role for APEN in maintaining nuclear and mitochondrial DNA integrity in spermatogenic cells throughout life.

Mitochondrion, 2010

p140 catalytic subunit. The aim of the current work is to biochemically characterize p55 proteins... more p140 catalytic subunit. The aim of the current work is to biochemically characterize p55 proteins that individually harbor these seven mutations. Biochemical assays have been set up to address: (1) whether the seven p55 variants bind to and stimulate p140, (2) whether these mutations affect folding or stability of p55; and (3) whether altered DNA binding is associated with any of the p55 variants? Preliminary results suggest that at least some of the variants are defective at stimulating p140 by monitoring the extension of a 5 0-end-labeled primer hybridized to M13 DNA. The ultimate goal of this work is to discover biochemical defects associated with novel POLG2 mutations that may give insights into the pathogenesis of mitochondrial disease.

DNA Repair, 2009

Many forms of neurodegeneration are associated with oxidative stress and mitochondrial dysfunctio... more Many forms of neurodegeneration are associated with oxidative stress and mitochondrial dysfunction. Mitochondria are prominent targets of oxidative damage, however, it is not clear whether mitochondrial DNA (mtDNA) damage and/or its lack of repair are primary events in the delayed onset observed in Huntington's disease (HD). We hypothesize that an age-dependent increase in mtDNA damage contributes to mitochondrial dysfunction in HD. Two HD mouse models were studied, the 3-nitropropionic acid (3-NPA) chemically induced model and the HD transgenic mice of the R6/2 strain containing 115-150 CAG repeats in the huntingtin gene. The mitochondrial toxin 3-NPA inhibits complex II of the electron transport system and causes neurodegeneration that resembles HD in the striatum of human and experimental animals. We measured nuclear and mtDNA damage by quantitative PCR (QPCR) in striatum of 5-and 24month-old untreated and 3-NPA treated C57BL/6 mice. Aging caused an increase in damage in both nuclear and mitochondrial genomes. 3-NPA induced 4-6 more damage in mtDNA than nuclear DNA in 5-month-old mice, and this damage was repaired by 48 h in the mtDNA. In 24month-old mice 3NPA caused equal amounts of nuclear and mitochondrial damage and this damage persistent in both genomes for 48 h. QPCR analysis showed a progressive increase in the levels of mtDNA damage in the striatum and cerebral cortex of 7-12-week-old R6/2 mice. Striatum exhibited eight-fold more damage to the mtDNA compared with a nuclear gene. These data suggest that mtDNA damage is an early biomarker for HD-associated neurodegeneration and supports the hypothesis that mtDNA lesions may contribute to the pathogenesis observed in HD.

Dataismo, 2021

El presente estudio describe los niveles de inteligencia emocional en adolescentes de escuelas pú... more El presente estudio describe los niveles de inteligencia emocional en adolescentes de escuelas públicas. Dicha investigación presenta una metodología dada en Declaración PRISMA, que presenta información relevante e importante obtenida en diferentes bases de datos bibliográficas como Scopus, EBSCO y Springer dado en un tiempo final de un año y siete meses. El proceso de identificación, cribado, elegibilidad e inclusión se desarrolló en dos meses. De los 120 artículos de investigación que dio origen a la búsqueda científica, se eligieron 15 que ayudaron a establecer el objetivo planteado. Los criterios de incorporación como artículos de investigación, revisiones sistemáticas y estudios de caso; revisados por pares, relacionados o interrelacionados con la temática a la variable inteligencia emocional fueron pieza clave para la elaboración de la revisión sistemática. Los criterios de eliminación e indagación que no fueron elegidos y sujetos a una elaboración de trabajo presentaron defic...

Dataismo, 2021

El objetivo de esta revisión sistemática fue analizar el desarrollo de las habilidades sociales e... more El objetivo de esta revisión sistemática fue analizar el desarrollo de las habilidades sociales en los docentes del magisterio. El estudio se desarrolló siguiendo la metodología establecida en la declaración PRISMA, la información científica se recuperó principalmente de Ebsco, Scopus y Springer en un periodo de dos meses. El proceso de identificación, cribado, elegibilidad e inclusión se desarrolló en un mes. De los 134 estudios que arrojó la búsqueda especializada, solamente se incluyeron 15. Criterios de inclusión: artículos de investigación, revisiones sistemáticas y estudio de casos, relacionados con las palabras habilidades sociales, docentes, habilidades básicas, planificación, sentimientos. Criterios de exclusión: investigaciones con deficiencias metodológicas o que no tienen relación con el objetivo del estudio. Los resultados indican que el desarrollo de las habilidades sociales son determinantes en los docentes del magisterio para el logro de una mejor calidad de vida en ...

Presentaciones orales A low degranulation ability of activated CD8 + T cells is associated with t... more Presentaciones orales A low degranulation ability of activated CD8 + T cells is associated with the persistent systemic immune activation in HIV-infected patients, despite viral suppression induced by the anti-retroviral therapy

Viruses, Sep 7, 2018

The high levels of dengue-virus (DENV) seroprevalence in areas where the Zika virus (ZIKV) is cir... more The high levels of dengue-virus (DENV) seroprevalence in areas where the Zika virus (ZIKV) is circulating and the cross-reactivity between these two viruses have raised concerns on the risk of increased ZIKV disease severity for patients with a history of previous DENV infections. To determine the role of DENV preimmunity in ZIKV infection, we analyzed the T- and B-cell responses against ZIKV in donors with or without previous DENV infection. Using peripheral blood mononuclear cells (PBMCs) from donors living in an endemic area in Colombia, we have identified, by interferon (IFN)-γ enzyme-linked immunospot (ELISPOT) assay, most of the immunodominant ZIKV T-cell epitopes in the nonstructural (NS) proteins NS1, NS3, and NS5. Analyses of the T- and B-cell responses in the same donors revealed a stronger T-cell response against peptides conserved between DENV and ZIKV, with a higher level of ZIKV-neutralizing antibodies in DENV-immune donors in comparison with DENV-naïve donors. Strikin...

Neotropical Biodiversity, 2016

Examining dispersal is critical for understanding the diversity of Andean-centered plant lineages... more Examining dispersal is critical for understanding the diversity of Andean-centered plant lineages, like Burmeistera (Campanulaceae). One-third of its species present an unusual inflated berry. Unlike the bright colors of non-inflated fruits in the genus, these fruits are typically dull-green; however, the fact that the seeds are loosely held in the placenta and easily removed when touched seems to suggest adaptation to animal dispersal. We studied two inflated-baccate species, Burmeistera glabrata and B. borjensis, with the aim of testing the non-exclusive hypotheses that their seeds are dispersed by (1) small mammals, (2) slugs, or (3) adult flies that develop inside the fruits. In two sites in the Ecuadorian Andes, we performed observations at dusk and dawn to examine the fate of fruits and seeds; recording fruit fall, formation of holes in the fruits, and seed loss from the placenta. We documented fruit visitors with cameras, and surveyed unopened fruits for the presence of insect larvae and seed condition. Finally, we performed an experiment to examine the effect of holes and rain in germination, in order to evaluate if holes are required for seeds to leave the fruits and subsequently germinate. For both species, most fruits fell and decomposed beneath the mother plant. However, we found limited support for small mammal dispersal; videos and observations revealed that mice and squirrels are potential, but rare, seed dispersers. We found no evidence for slug or fly dispersal; fly larvae were common inside fruits, but acted exclusively as seed predators. Crickets often chewed holes in fruits on plants and on the ground. Holes did not have an effect on germination, which was induced only by rain. Hence, the majority of seeds end up under the mother plant, with rare but potentially important events of primary or secondary dispersal by small mammals. The combination of limited dispersal due to gravity and rare events of mammal dispersal may have played a critical role in the rapid diversification of Burmeistera.

Projektet handlar om att forbattra diabetikers livskvalitet genom att forska kring hur en framtid... more Projektet handlar om att forbattra diabetikers livskvalitet genom att forska kring hur en framtida insulinpump med integrerad blodsockermatare bor utformas for att tilltala anvandarna. Det syftar t ...

For many years, the United States has been known as the great “melting pot” with a mixture of peo... more For many years, the United States has been known as the great “melting pot” with a mixture of people representing different races and ethnicities that have come together to form one nation and one American identity. The American educational system has attempted to facilitate the creation of one national identity through the process of assimilation and through its insistence that

Molecular Reproduction and Development, 2011

The prevalence of spontaneous mutations increases with age in the male germline; consequently, ol... more The prevalence of spontaneous mutations increases with age in the male germline; consequently, older men have an increased risk of siring children with genetic disease due to de novo mutations. The lacI transgenic mouse can be used to study paternal age effects, and in this system, the prevalence of de novo mutations increases in the male germline at old ages. Mutagenesis is linked with DNA repair capacity, and base excision repair, which can ameliorate spontaneous DNA damage, decreases in nuclear extracts of spermatogenic cells from old mice. Mice heterozygous for a null allele of the Apex1 gene, which encodes apurinic/apyrimidinic endonuclease I (APEN), an essential base excision repair enzyme, display an accelerated increase in spontaneous germline mutagenesis early in life. Here, the consequences of lifelong reduction of APEN on genetic instability in the male germline were examined, for the first time, at middle and old ages. Mutation frequency increased earlier in spermatogenic cells from Apex1 +/− mice (by 6 months of age). Nuclear DNA damage increased with age in the spermatogenic lineage for both wild-type and Apex1 +/− mice. By old age, mutation frequencies were similar for wild-type and APEN-deficient mice. Mitochondrial genome repair also depends on APEN, and novel analysis of mitochondrial DNA damage revealed an increase in the Apex1 +/− spermatogenic cells by middle age. Thus, Apex1 heterozygosity results in accelerated damage to mitochondrial DNA and spontaneous mutagenesis, consistent with an essential role for APEN in maintaining nuclear and mitochondrial DNA integrity in spermatogenic cells throughout life.

Mitochondrion, 2010

p140 catalytic subunit. The aim of the current work is to biochemically characterize p55 proteins... more p140 catalytic subunit. The aim of the current work is to biochemically characterize p55 proteins that individually harbor these seven mutations. Biochemical assays have been set up to address: (1) whether the seven p55 variants bind to and stimulate p140, (2) whether these mutations affect folding or stability of p55; and (3) whether altered DNA binding is associated with any of the p55 variants? Preliminary results suggest that at least some of the variants are defective at stimulating p140 by monitoring the extension of a 5 0-end-labeled primer hybridized to M13 DNA. The ultimate goal of this work is to discover biochemical defects associated with novel POLG2 mutations that may give insights into the pathogenesis of mitochondrial disease.

DNA Repair, 2009

Many forms of neurodegeneration are associated with oxidative stress and mitochondrial dysfunctio... more Many forms of neurodegeneration are associated with oxidative stress and mitochondrial dysfunction. Mitochondria are prominent targets of oxidative damage, however, it is not clear whether mitochondrial DNA (mtDNA) damage and/or its lack of repair are primary events in the delayed onset observed in Huntington's disease (HD). We hypothesize that an age-dependent increase in mtDNA damage contributes to mitochondrial dysfunction in HD. Two HD mouse models were studied, the 3-nitropropionic acid (3-NPA) chemically induced model and the HD transgenic mice of the R6/2 strain containing 115-150 CAG repeats in the huntingtin gene. The mitochondrial toxin 3-NPA inhibits complex II of the electron transport system and causes neurodegeneration that resembles HD in the striatum of human and experimental animals. We measured nuclear and mtDNA damage by quantitative PCR (QPCR) in striatum of 5-and 24month-old untreated and 3-NPA treated C57BL/6 mice. Aging caused an increase in damage in both nuclear and mitochondrial genomes. 3-NPA induced 4-6 more damage in mtDNA than nuclear DNA in 5-month-old mice, and this damage was repaired by 48 h in the mtDNA. In 24month-old mice 3NPA caused equal amounts of nuclear and mitochondrial damage and this damage persistent in both genomes for 48 h. QPCR analysis showed a progressive increase in the levels of mtDNA damage in the striatum and cerebral cortex of 7-12-week-old R6/2 mice. Striatum exhibited eight-fold more damage to the mtDNA compared with a nuclear gene. These data suggest that mtDNA damage is an early biomarker for HD-associated neurodegeneration and supports the hypothesis that mtDNA lesions may contribute to the pathogenesis observed in HD.