458 research outputs found

    EL PROMISORIO CAMINO DE LA TECNOLOGÍA CRISPR-CAS9 EN LA EDICIÓN GENÓMICA

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    CRISPR, grupo de repeticiones cortas palindrómicas regularmente espaciadas (clustered regularly interspaced short palindromicrepeat), es un sistema de defensa viral encontrado en el genoma de bacterias y arqueas. La transcripción de estas secuencias CRISPR, que portan ADN viral asimilado previamente (espaciadores), produce crARNs que, en complejo con complejos  multiproteicos asociados a CRISPR, Cas (CRISPR associated), catalizan la degradación de material genético invasor que porte secuencias complementarias a los crARNs (protoespaciadores). En Streptococcus pyogenes, Cas9 en la única proteína encargada de efectuar los cortes de doble hebra en el ADN extraño, proporcionando un sistema in vitro e in vivo rápido, simple y barato para introducir cortes y mutaciones en cualquier región deseada, en tanto Cas9 sea programada con un crARN específico, llamado específicamente gARN, sgARN o chiARN. La tecnología CRISPR-Cas9 puede aplicarse eficientemente a una gran variedad de organismos procariotas y eucariotas, es decir, constituye una herramienta de inestimable poder en la edición genómica y estudio de la función de los genes.&nbsp

    Photoluminescence Enhancement by Band Alignment Engineering in MoS2/FePS3 van der Waals Heterostructures

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    Single-layer semiconducting transition metal dichalcogenides (2H-TMDs) display robust excitonic photoluminescence emission, which can be improved by controlled changes to the environment and the chemical potential of the material. However, a drastic emission quench has been generally observed when TMDs are stacked in van der Waals heterostructures, which often favor the nonradiative recombination of photocarriers. Herein, we achieve an enhancement of the photoluminescence of single-layer MoS2 on top of van der Waals FePS3. The optimal energy band alignment of this heterostructure preserves light emission of MoS2 against nonradiative interlayer recombination processes and favors the charge transfer from MoS2, an n-type semiconductor, to FePS3, a p-type narrow-gap semiconductor. The strong depletion of carriers in the MoS2 layer is evidenced by a dramatic increase in the spectral weight of neutral excitons, which is strongly modulated by the thickness of the FePS3 underneath, leading to the increase of photoluminescence intensity. The present results demonstrate the potential for the rational design of van der Waals heterostructures with advanced optoelectronic properties.The authors acknowledge funding from Generalitat Valenciana through grants IDIFEDER/2020/005, IDIFEDER/2018/061, PROMETEO Program and PO FEDER Program, the APOSTD/2020/249 fellowship for M.R., and support from the Plan Gen-T of Excellence for J.J.B. (CDEIGENT/ 2019/022), J.C.-F. (CIDEGENT/2018/005), and M.R.C (CideGenT2018004); from the Spanish MCINN through grants PLASTOP PID2020-119124RB-I00, 2D-HETEROS PID2020-117152RB-100, and Excellence Unit “María de Maeztu” CEX2019-000919-M; and from the European Union (ERC-2021-StG-101042680 2D-SMARTiES and ERC AdG Mol-2D 788222)

    What kinds of value motives guide people in their moral attitudes? The role of personal and prescriptive values at the culture level and individual level

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    Opinions about moralized issues are arguably one of the most difficult issues in interpersonal dialogues given that they can result in intolerance and prejudicial behavior toward those with divergent moral beliefs. Recent research has shown that moral attitudes vary not only depending on the individual's characteristics but also as a function of culture. Individuals from individualistic-oriented cultures exhibit more lenient judgments toward moralized issues than those from collectivistic-oriented cultures. What is unclear to date is what kinds of cultural value motives underlie these attitudesAre they driven only by intrinsic value motives (personal values) or also by extrinsic value motives (prescriptive values in the form of societal expectations about what should be valued)? The cultural press to conform is arguably stronger if moral attitudes are predicted by the latter. Participants from eight countries (N = 1,456) responded to a questionnaire containing a modified version of the Schwartz Value Survey assessing personal and prescriptive values. The results showed that personal value ratings of openness-to-change versus conservation at the culture and individual levels were predictive of individuals' moral attitudes consistent with previous findings. Prescriptive value ratings of openness-to-change versus conservation also predicted individuals' moral attitudes, but only at the aggregated culture level. This suggests that the prescriptive values concept is a truly group-level phenomenon and that attitudes toward moralized issues are guided by cultural values with normative qualities. We discuss the implications for intercultural contact situations.info:eu-repo/semantics/acceptedVersio

    Exploring Dietary Behavior Changes Due to the COVID-19 Confinement in Colombia: A National and Regional Survey Study

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    The authors would like to extend their gratitude and acknowledgments to all study participants and to all Foundations, Institutions, and Societies that supported the survey, helping in the process of dissemination: Asociacion Colombiana de Dietistas y Nutricionistas, ACODIN, Asociacion Colombiana de Facultades de Nutricion y Dietetica (ACOFANUD), Asociacion de Egresados de Nutricion y Dietetica de la Universidad Nacional (ANDUN), Colegio colombiano de nutricionistas Dietistas-COLNUD, Observatorio de Soberania y Seguridad alimentaria y Nutricional de la Universidad Nacional de Colombia (OBSSAN UN). The authors are also thankful to Gloria Esperanza Prada Gomez from Universidad Industrial de Santander (Facultad de Salud, Escuela de Nutricion y Dietetica), who also supported the dissemination of the survey in the Eastern region of Colombia. Sonia Liliana Pertuz Cruz is thankful to Fundacion Carolina, for a doctoral scholarship award.The aim of this study was to evaluate the impact of coronavirus SARS-Cov2 (COVID-19) confinement measures in Colombia on the dietary behaviors of a large population sample, at national and regional levels. A survey was conducted to assess dietary behaviors during the COVID-19 confinement. The survey involved 2,745 participants, aged 18 years or older, from six regions of the country (Atlantica, Bogota, Central, Oriental, Orinoquia and Amazonia, and Pacifica). Dietary intake of foods and foods groups in grams per day before and during the confinement was estimated by considering standard serving sizes of foods. One-way ANOVA was used to analyze differences between the regions with regard to dietary behavior changes during the confinement. Differences were deemed significant at p-value < 0.05. Dietary patterns (DPs) before and during the confinement were derived from principal component analysis. Certain dietary habits were adopted by the study population during the confinement (e.g., higher frequency of snacking and home cooking), with significant differences by regions with regard to these habits, as well as regarding culinary processes. The levels of consumption of several foods also changed during the confinement, nationally and regionally. We identified three DPs before the confinement (protein-rich, carbohydrate-rich, and sugar foods patterns) and four DPs during the confinement (westernized, carbohydrate-rich, protein-rich, fish and fruits-vegetable patterns), with an explained total variance of 33 and 45%, respectively. The profile of these DPs varied to some extent between the regions; their adherence to each DP also varied (p-value < 0.001). Our results show that there were marked differences by regions in the dietary behaviors of this population during the confinement, with an overall trend toward unhealthier DPs. These results may help to shape public health nutrition interventions in Colombia during the COVID-19 pandemic and in a post-COVID stage.Fundacion CarolinaAsociacion Colombiana de Dietistas y Nutricionistas, ACODINAsociacion Colombiana de Facultades de Nutricion y Dietetica (ACOFANUD)Asociacion de Egresados de Nutricion y Dietetica de la Universidad Nacional (ANDUN)Colegio colombiano de nutricionistas Dietistas-COLNUDObservatorio de Soberania y Seguridad alimentaria y Nutricional de la Universidad Nacional de Colombia (OBSSAN UN

    Excitotoxic inactivation of constitutive oxidative stress detoxification pathway in neurons can be rescued by PKD1

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    Excitotoxicity, a critical process in neurodegeneration, induces oxidative stress and neuronal death through mechanisms largely unknown. Since oxidative stress activates protein kinase D1 (PKD1) in tumor cells, we investigated the effect of excitotoxicity on neuronal PKD1 activity. Unexpectedly, we find that excitotoxicity provokes an early inactivation of PKD1 through a dephosphorylation-dependent mechanism mediated by protein phosphatase-1 (PP1) and dual specificity phosphatase-1 (DUSP1). This step turns off the IKK/NF-κB/SOD2 antioxidant pathway. Neuronal PKD1 inactivation by pharmacological inhibition or lentiviral silencing in vitro, or by genetic inactivation in neurons in vivo, strongly enhances excitotoxic neuronal death. In contrast, expression of an active dephosphorylation-resistant PKD1 mutant potentiates the IKK/NF-κB/SOD2 oxidative stress detoxification pathway and confers neuroprotection from in vitro and in vivo excitotoxicity. Our results indicate that PKD1 inactivation underlies excitotoxicity-induced neuronal death and suggest that PKD1 inactivation may be critical for the accumulation of oxidation-induced neuronal damage during aging and in neurodegenerative disorders

    Consecuencias del estrés calórico sobre la reproducción del ganado vacuno

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    Heat stress represents one of the major environmental factors that adversely affect the reproductive performance of cattle. In this paper the behavioral adjustments, physical mechanisms and physiological responses to heat loss are described; bos indicus adaptive advantages with respect to bos Taurus, pathophysiology of heat stress and heat stress effects in animal reproduction, both the male and the female.El estrés calórico representa unos de los principales factores del medio ambiente que repercuten negativamente en el desempeño reproductivo del ganado vacuno. En este trabajo se describen los ajustes conductuales, mecanismos físicos y respuestas fisiológicas para la pérdida calórica; ventajas adaptativas del bos indicus con respecto al bos Taurus, fisiopatología del estrés calórico y repercusiones del estrés calórico en la reproducción animal, tanto en el macho como en la hembra

    Mapping of Mycobacterium tuberculosis Complex Genetic Diversity Profiles in Tanzania and Other African Countries

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    The aim of this study was to assess and characterize Mycobacterium tuberculosis complex (MTBC) genotypic diversity in Tanzania, as well as in neighbouring East and other several African countries. We used spoligotyping to identify a total of 293 M. tuberculosis clinical isolates (one isolate per patient) collected in the Bunda, Dar es Salaam, Ngorongoro and Serengeti areas in Tanzania. The results were compared with results in the SITVIT2 international database of the Pasteur Institute of Guadeloupe. Genotyping and phylogeographical analyses highlighted the predominance of the CAS, T, EAI, and LAM MTBC lineages in Tanzania. The three most frequent Spoligotype International Types (SITs) were: SIT21/CAS1-Kili (n = 76; 25.94%), SIT59/LAM11-ZWE (n = 22; 7.51%), and SIT126/EAI5 tentatively reclassified as EAI3-TZA (n = 18; 6.14%). Furthermore, three SITs were newly created in this study (SIT4056/EAI5 n = 2, SIT4057/T1 n = 1, and SIT4058/EAI5 n = 1). We noted that the East-African-Indian (EAI) lineage was more predominant in Bunda, the Manu lineage was more common among strains isolated in Ngorongoro, and the Central-Asian (CAS) lineage was more predominant in Dar es Salaam (p-value<0.0001). No statistically significant differences were noted when comparing HIV status of patients vs. major lineages (p-value = 0.103). However, when grouping lineages as Principal Genetic Groups (PGG), we noticed that PGG2/3 group (Haarlem, LAM, S, T, and X) was more associated with HIV-positive patients as compared to PGG1 group (Beijing, CAS, EAI, and Manu) (p-value = 0.03). This study provided mapping of MTBC genetic diversity in Tanzania (containing information on isolates from different cities) and neighbouring East African and other several African countries highlighting differences as regards to MTBC genotypic distribution between Tanzania and other African countries. This work also allowed underlining of spoligotyping patterns tentatively grouped within the newly designated EAI3-TZA lineage (remarkable by absence of spacers 2 and 3, and represented by SIT126) which seems to be specific to Tanzania. However, further genotyping information would be needed to confirm this specificity

    INFECCIONES OPORTUNISTAS PRESENTES EN INDIVIDUOS CON VIH/SIDA: VIRUS DEL HERPES SIMPLE TIPO 1 Y 2, CITOMEGALOVIRUS Y HERPESVIRUS TIPO 8 ASOCIADO A SARCOMA DE KAPOSI

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    Las enfermedades oportunistas abarcan un conjunto de patologías que, como su nombre lo indica, aprovechan "oportunamente" la disminución en la calidad de respuesta del sistema inmune de los pacientes VIH-1 positivos para proliferar en el organismo. En muchos casos, se trata de enfermedades que no aparecerían si el sistema inmunológico se encontrara en su estado normal, sin embargo, esto no significa que sean enfermedades exclusivas de las personas con VIH. Cuando una persona esta infectada con VIH, su sistema inmunológico se ve comprometido es decir, disminuye notablemente su capacidad de atacar a microorganismos patógenos, debido a una reducción en las cuentas de linfocitos T CD4+ (&lt; 200/μl). A partir de este momento, en el que el sistema inmune se encuentra suprimido, diversos microorganismos oportunistas desencadenan una serie de infecciones y algunos tipos de cáncer en el individuo. Una gran proporción de las co-infecciones virales observadas en la infección VIH-SIDA son producidas por miembros de la familia Herpesviridae. En un estudio efectuado en nuestro laboratorio de  seroprevalencia por Citomegalovirus, Virus del Herpes Simple tipo 2 y Virusdel Herpes tipo 8 relacionado con Sarcoma de Kaposi, en pacientes infectados con VIH/SIDA bajo tratamiento antiretroviral encontramos que, de un total de 31 individuos infectados con VIH, el 100% presentaron anticuerpos para Citomegalovirus, un 35% para el Virus del Herpes Simple tipo 2 y un 22% para el Virus del Herpes tipo 8 relacionado con el Sarcoma de Kaposi.Palabras Clave: VIH-1, Infecciones Oportunistas, Herpesviridae.HIV-1, Opportunistic infections, Herpesviridae

    Towards actionable knowledge: A systematic analysis of mobile patient portal use

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    As the aging population grows, chronic illness increases, and our healthcare costs sharply increase, patient portals are positioned as a central component of patient engagement through the potential to change the physician-patient relationship and enable chronic disease self-management. A patient’s engagement in their healthcare contributes to improving health outcomes, and information technologies can support health engagement. In this chapter, we extend the existing literature by discovering design gaps for patient portals from a systematic analysis of negative users’ feedback from the actual use of patient portals. Specifically, we adopt a topic modeling approach, latent Dirichlet allocation (LDA) algorithm, to discover design gaps from online low rating user reviews of a common mobile patient portal, EPIC’s mychart. To validate the extracted gaps, we compared the results of LDA analysis with that of human analysis. Overall, the results revealed opportunities to improve collaboration and to enhance the design of portals intended for patient-centered care. Incorporating these changes may enable the technologies to have stronger position to influence health improvement and wellness

    From Nuevo León to the USA and Back Again: Transnational Students in Mexico

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    The movement of Mexicans to the United States is both longstanding and long studied and from that study we know that for many newcomers the attachment to the receiving community is fraught and tentative. The experience of immigrant children in U.S. schools is also relatively well studied and reveals challenges of intercultural communication as well as concurrent and contradictory features of welcome and unwelcome. What is less well known, in the study of migration generally and of transnational students in particular, is how students moving in a less common direction — from the U.S. to Mexico — experience that movement. Based on visits to 173 randomly selected classrooms in the state of Nuevo León Mexico, this study shares survey and interview data from 208 of the 242 students encountered who had previous experience attending school in the United States
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