148 research outputs found

    SLC30A3 (ZnT3) Oligomerization by Dityrosine Bonds Regulates Its Subcellular Localization and Metal Transport Capacity

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    Non-covalent and covalent homo-oligomerization of membrane proteins regulates their subcellular localization and function. Here, we described a novel oligomerization mechanism affecting solute carrier family 30 member 3/zinc transporter 3 (SLC30A3/ZnT3). Oligomerization was mediated by intermolecular covalent dityrosine bonds. Using mutagenized ZnT3 expressed in PC12 cells, we identified two critical tyrosine residues necessary for dityrosine-mediated ZnT3 oligomerization. ZnT3 carrying the Y372F mutation prevented ZnT3 oligomerization, decreased ZnT3 targeting to synaptic-like microvesicles (SLMVs), and decreased resistance to zinc toxicity. Strikingly, ZnT3 harboring the Y357F mutation behaved as a “gain-of-function” mutant as it displayed increased ZnT3 oligomerization, targeting to SLMVs, and increased resistance to zinc toxicity. Single and double tyrosine ZnT3 mutants indicate that the predominant dimeric species is formed between tyrosine 357 and 372. ZnT3 tyrosine dimerization was detected under normal conditions and it was enhanced by oxidative stress. Covalent species were also detected in other SLC30A zinc transporters localized in different subcellular compartments. These results indicate that covalent tyrosine dimerization of a SLC30A family member modulates its subcellular localization and zinc transport capacity. We propose that dityrosine-dependent membrane protein oligomerization may regulate the function of diverse membrane protein in normal and disease states

    Evaluación del proceso de comunicación vivido en la ejecución del programa Liderazgo Juvenil del Instituto FES de Liderazgo

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    Tesis (Comunicador Social-Periodista)-- Corporación Universitaria Autónoma de Occidente. División Comunicación Social-Periodismo, 1991PregradoComunicador(a) Social – Periodist

    Colegio de Educadores de Párvulos de Chile AG

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    This paper describes the Colegio de Educadores de Párvulos de Chile AG, its organization, operation and activities concerning professional practice and nation wide’s Early Childhood Educational Development. It also presents some collegiate approaches referred to Chilean Educational Reform, at this level.Este artículo intenta describir al Colegio de Educadores de Párvulos de Chile AG, su organización, funcionamiento y actividades realizadas en cuanto al ejercicio profesional y al desarrollo de la Educación Parvularia del país. Presenta también planteamientos de algunas colegiadas referidos al deber ser de la Reforma Educacional chilena en este nivel

    The Interpretation and application of the law with a gender perspective in Spain: challenges and outstanding issues

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    This work, situated within the Spanish legal context, presents a reflection upon the need to apply and interpret the law bearing in mind the mandate of the gender perspective contained in national and international legislation. In spite of the significant advances, in questions of gender equality, evidenced by the Spanish legal system in recent decades, these have not led to real, effective equality. In the spheres of both private and public law, this task should be prioritised and undertaken in transversal fashion by all legal operators, judges in particular. Without this commitment, the guarantee of women’s human rights will continue to be hindered by the shortcomings of an androcentric legal culture that perpetuates structural discrimination against women

    Genetic Susceptibility Loci of Idiopathic Interstitial Pneumonia do not Represent Risk for Systemic Sclerosis: a Case Control Study in Caucasian Patients

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    Background: Systemic sclerosis (SSc)-related interstitial lung disease (ILD) has phenotypic similarities to lung involvement in idiopathic interstitial pneumonia (IIP). We aimed to assess whether genetic susceptibility loci recently identified in the large IIP genome-wide association studies (GWASs) were also risk loci for SSc overall or severity of ILD in SSc. Methods: A total of 2571 SSc patients and 4500 healthy controls were investigated from the US discovery GWAS and additional US replication cohorts. Thirteen IIP-related selected single nucleotide polymorphisms (SNPs) were genotyped and analyzed for their association with SSc. Results: We found an association of SSc with the SNP rs6793295 in the LRRC34 gene (OR = 1.14, CI 95 % 1.03 to 1.25, p value = 0.009) and rs11191865 in the OBFC1 gene (OR = 1.09, CI 95 % 1.00 to 1.19, p value = 0.043) in the discovery cohort. Additionally, rs7934606 in MUC2 (OR = 1.24, CI 95 % 1.01 to 1.52, p value = 0.037) was associated with SSc-ILD defined by imaging. However, these associations failed to replicate in the validation cohort. Furthermore, SNPs rs2076295 in DSP ( β = -2.29, CI 95 % -3.85 to -0.74, p value = 0.004) rs17690703 in SPPL2C ( β = 2.04, CI 95 % 0.21 to 3.88, p value = 0.029) and rs1981997 in MAPT ( β = 2.26, CI 95 % 0.35 to 4.17, p value = 0.02) were associated with percent predicted forced vital capacity (FVC%) even after adjusting for the anti-topoisomerase (ATA)-positive subset. However, these associations also did not replicate in the validation cohort. Conclusions: Our results add new evidence that SSc and SSc-related ILD are genetically distinct from IIP, although they share phenotypic similarities

    Dengue en el embarazo: efectos en el feto y el recién nacido.

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    The risk of dengue virus infection during pregnancy has increased due to the current rash of frequent and severe dengue epidemics. The effects of dengue virus in the fetus and newborn children have been studied only superficially and with contradictory results. Therefore, a retrospective cohort study was conducted in Medellin, Colombia, to describe the fetal and postnatal effects of dengue virus infection acquired during pregnancy. Twenty-two babies born from mothers who suffered dengue during the epidemics of 1998 were compared with babies from non-infected mothers. In the exposed cohort, three premature births occurred, three children suffered from fetal anomalies and four children were born with low weight. In the non-exposed children, none of these problems were found. Psychomotor development was normal in both groups. Only the low weight subgroup was statistically significant (Fisher test, p = 0.045). These results suggested that the children from women with dengue during pregnancy present low weight, greater frequency of premature birth and increased fetal distress. A larger sample is necessary to confirm these results.El riesgo de infección por el virus del dengue durante el embarazo se está incrementando ante mayores y más severas epidemias, y las consecuencias sobre el feto y el recién nacido han sido poco estudiadas y, en otros casos, los resultados han sido contradictorios. Por esta razón, se realizó en Medellín un estudio de cohorte retrospectiva, cuyo objetivo fue determinar los efectos que produce el dengue durante el embarazo sobre el feto y el recién nacido. En dicho estudio se evaluaron 22 recién nacidos hijos de mujeres que presentaron dengue durante la epidemia de 1998 y se compararon con 24 recién nacidos, hijos de mujeres embarazadas sin dengue. En la cohorte con dengue se encontraron 3 niños prematuros, 3 niños con sufrimiento fetal y 4 niños con bajo peso al nacer. En la cohorte no expuesta no se encontraron niños con estos problemas. El desarrollo psicomotor fue normal en ambos grupos. De las observaciones anteriores, sólo fue estadísticamente significativa la frecuencia de niños con bajo peso al nacer (prueba exacta de Fisher, p=0,045). Estos resultados preliminares muestran que los recién nacidos de madres que sufrieron dengue durante la gestación tuvieron riesgo de bajo peso al nacer y presentaron con mayor frecuencia prematurez y sufrimiento fetal, aunque se requiere aumentar el tamaño de la muestra para confirmar estos resultados. Sin embargo, es necesario estrechar la vigilancia a las madres embarazadas con dengue dados los efectos nocivos sobre la evolución del recién nacido

    Unique functions for Notch4 in murine embryonic lymphangiogenesis

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    Publisher Copyright: © 2021, The Author(s).In mice, embryonic dermal lymphatic development is well understood and used to study gene functions in lymphangiogenesis. Notch signaling is an evolutionarily conserved pathway that modulates cell fate decisions, which has been shown to both inhibit and promote dermal lymphangiogenesis. Here, we demonstrate distinct roles for Notch4 signaling versus canonical Notch signaling in embryonic dermal lymphangiogenesis. Actively growing embryonic dermal lymphatics expressed NOTCH1, NOTCH4, and DLL4 which correlated with Notch activity. In lymphatic endothelial cells (LECs), DLL4 activation of Notch induced a subset of Notch effectors and lymphatic genes, which were distinctly regulated by Notch1 and Notch4 activation. Treatment of LECs with VEGF-A or VEGF-C upregulated Dll4 transcripts and differentially and temporally regulated the expression of Notch1 and Hes/Hey genes. Mice nullizygous for Notch4 had an increase in the closure of the lymphangiogenic fronts which correlated with reduced vessel caliber in the maturing lymphatic plexus at E14.5 and reduced branching at E16.5. Activation of Notch4 suppressed LEC migration in a wounding assay significantly more than Notch1, suggesting a dominant role for Notch4 in regulating LEC migration. Unlike Notch4 nulls, inhibition of canonical Notch signaling by expressing a dominant negative form of MAML1 (DNMAML) in Prox1+ LECs led to increased lymphatic density consistent with an increase in LEC proliferation, described for the loss of LEC Notch1. Moreover, loss of Notch4 did not affect LEC canonical Notch signaling. Thus, we propose that Notch4 signaling and canonical Notch signaling have distinct functions in the coordination of embryonic dermal lymphangiogenesis.Peer reviewe

    Angiotensin II Requires Zinc and Downregulation of the Zinc Transporters ZnT3 and ZnT10 to Induce Senescence of Vascular Smooth Muscle Cells

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    Senescence, a hallmark of mammalian aging, is associated with the onset and progression of cardiovascular disease. Angiotensin II (Ang II) signaling and zinc homeostasis dysfunction are increased with age and are linked to cardiovascular disease, but the relationship among these processes has not been investigated. We used a model of cellular senescence induced by Ang II in vascular smooth muscle cells (VSMCs) to explore the role of zinc in vascular dysfunction. We found that Ang II-induced senescence is a zinc-dependent pathway mediated by the downregulation of the zinc transporters ZnT3 and ZnT10, which work to reduce cytosolic zinc. Zinc mimics Ang II by increasing reactive oxygen species (ROS), activating NADPH oxidase activity and Akt, and by downregulating ZnT3 and ZnT10 and inducing senescence. Zinc increases Ang II-induced senescence, while the zinc chelator TPEN, as well as overexpression of ZnT3 or ZnT10, decreases ROS and prevents senescence. Using HEK293 cells, we found that ZnT10 localizes in recycling endosomes and transports zinc into vesicles to prevent zinc toxicity. Zinc and ZnT3/ZnT10 downregulation induces senescence by decreasing the expression of catalase. Consistently, ZnT3 and ZnT10 downregulation by siRNA increases ROS while downregulation of catalase by siRNA induces senescence. Zinc, siZnT3 and siZnT10 downregulate catalase by a post-transcriptional mechanism mediated by decreased phosphorylation of ERK1/2. These data demonstrate that zinc homeostasis dysfunction by decreased expression of ZnT3 or ZnT10 promotes senescence and that Ang II-induced senescence is a zinc and ROS-dependent process. Our studies suggest that zinc might also affect other ROS-dependent processes induced by Ang II, such as hypertrophy and migration of smooth muscle cells

    A novel modelling toolkit for unpacking the Water-Energy-Food-Environment (WEFE) nexus of agricultural development

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    Increasing food demand has led to significant agricultural expansion globally with negative impacts on resources and the environment, a perfect manifestation of the Water-Energy-Food-Environment nexus. Whilst many tools have been developed to understand the complexity of the Water-Energy-Food-Environment nexus most have failed to explicitly consider biophysical and socio-economic aspects simultaneously. A novel Water-Energy-Food-Environment modelling toolkit is developed that integrates both these components by combining different modelling approaches including irrigation simulation, economic modelling and life cycle environmental assessment. The toolkit is demonstrated using two major agro-export crops (asparagus and table grapes) in the Ica Valley, Peru, a severely water-stressed region. The toolkit was able to provide novel insights into the implications of different farming practices on resource efficiency at the field level in relation to water and energy, under contrasting future scenarios reflecting socio-economic outcomes at the local to regional levels (e.g., food prices, employment, and income) as well as environmental impacts at local to global scales. This information enables different stakeholders to better understand the interlinkages and inter-dependences between the Water-Energy-Food-Environment nexus elements and the complex impacts of agricultural expansion beyond the immediate sector and its geographical extent, helping decision makers design more coordinated agricultural policies and support sustainable agricultural transformation.Natural Environment Research Council (NERC): NE/R015759/1. Chilean National Agency for Research and Development (ANID/CONICYT) - FONDE
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