Novel fluorescence membrane fusion assays reveal GTP-dependent fusogenic properties of outer mitochondrial membrane-derived proteins

We have shown that fusion of small unilamellar vesicles (SUV) with outer mitochondrial membranes occurs at physiological pH [Cortese et al., 1991, J. Cell Biol., Vol. 113, 1331-1340]. The proteins driving this process could be involved in mitochondrial membrane fusion, which is presently poorly understood. In this study, we release from rat liver mitochondria a soluble protein fraction (SF) that increases fusion at neutral pH measured by membrane fusion assays (MFAs). Since this fusogenic activity was specifically enhanced by GTP, we separate SF by GTP affinity chromatography into: i) a flow-through subfraction (G1) containing numerous proteins with low GTP affinity; and ii) a subfraction (G2) which may contain GTP-binding proteins. A novel array of MFAs is developed to study the fusogenic properties of these fractions, measuring the merging of membranes (membrane-mixing) or the mixing of intravesicular aqueous contents (content-mixing). The MFAs use: a) SUV/large unilamellar vesicles, lacking mitochondrial membranes; b) SUV/mitochondria, reconstituting membrane-mitochondrial interactions; and c) mitochondria/mitochondria, mimicking mitochondrial fusion. The results indicate that: i) G1 contains GTP-independent, in vitro fusogenic proteins that are not sufficient to induce mitochondrial fusion; and ii) G2 contains GTP-dependent proteins that stimulate mitochondrial fusion at neutral pH. The MFAs described here could be used to monitor the isolation of active proteins from these subfractions and to define the mechanism of intermitochondrial membrane fusion

Aorta macrophage inflammatory and epigenetic changes in a murine model of obstructive sleep apnea: Potential role of CD36

Obstructive sleep apnea (OSA) affects 8-10% of the population, is characterized by chronic intermittent hypoxia (CIH), and causally associates with cardiovascular morbidities. In CIH-exposed mice, closely mimicking the chronicity of human OSA, increased accumulation and proliferation of pro-inflammatory metabolic M1-like macrophages highly expressing CD36, emerged in aorta. Transcriptomic and MeDIP-seq approaches identified activation of pro-atherogenic pathways involving a complex interplay of histone modifications in functionally-relevant biological pathways, such as inflammation and oxidative stress in aorta macrophages. Discontinuation of CIH did not elicit significant improvements in aorta wall macrophage phenotype. However, CIH-induced aorta changes were absent in CD36 knockout mice, Our results provide mechanistic insights showing that CIH exposures during sleep in absence of concurrent pro-atherogenic settings (i.e., genetic propensity or dietary manipulation) lead to the recruitment of CD36(+)high macrophages to the aortic wall and trigger atherogenesis. Furthermore, long-term CIH-induced changes may not be reversible with usual OSA treatment

Single Top Quark Production via FCNC Couplings at Hadron Colliders

We calculate single top-quark production at hadron colliders via the chromo-magnetic flavor-changing neutral current couplings $\bar tcg$ and $\bar tug$. We find that the strength for the anomalous $\bar tcg$ ($\bar tug$) coupling may be probed to $\kappa_c / \Lambda = 0.092 {TeV}^{-1}$ ($\kappa_u / \Lambda = 0.026 {TeV}^{-1}$) at the Tevatron with $2 {fb}^{-1}$ of data and $\kappa_c / \Lambda = 0.013 {TeV}^{-1}$ ($\kappa_u / \Lambda = 0.0061 {TeV}^{-1}$) at the LHC with $10 {fb}^{-1}$ of data. The two couplings may be distinguished by a comparision of the single top signal with the direct top and top decay signals for these couplings.Comment: 18 pages, 6 figures, 3 table

Mice Lacking Phosphatidylinositol Transfer Protein-α Exhibit Spinocerebellar Degeneration, Intestinal and Hepatic Steatosis, and Hypoglycemia

Phosphatidylinositol transfer proteins (PITPs) regulate the interface between lipid metabolism and cellular functions. We now report that ablation of PITP alpha function leads to aponecrotic spinocerebellar disease, hypoglycemia, and intestinal and hepatic steatosis in mice. The data indicate that hypoglycemia is in part associated with reduced proglucagon gene expression and glycogenolysis that result from pancreatic islet cell defects. The intestinal and hepatic steatosis results from the intracellular accumulation of neutral lipid and free fatty acid mass in these organs and suggests defective trafficking of triglycerides and diacylglycerols from the endoplasmic reticulum. We propose that deranged intestinal and hepatic lipid metabolism and defective proglucagon gene expression contribute to hypoglycemia in PITP alpha-/- mice, and that hypoglycemia is a significant contributing factor in the onset of spinocerebellar disease. Taken together, the data suggest an unanticipated role for PITP alpha in with glucose homeostasis and in mammalian endoplasmic reticulum functions that interface with transport of specific luminal lipid cargoes

La puesta en valor de los servicios ecosistémicos que ofrecen los arroyos de llanura como una medida de mitigación de las inundaciones: el caso del A° del Gato en el partido de La Plata

El concepto de servicios ecosistémicos surge en la década de los 70 como una forma de dar a conocer a la sociedad y a los tomadores de decisiones el vínculo directo que existe entre el bienestar humano y el mantenimiento de las funciones básicas del planeta. Más específicamente los servicios ecosistémicos hidrológicos se relacionan con la conservación de las cuencas hidrográficas entre los que se reconocen la regulación de flujos hidrológicos, reducción del impacto de las inundaciones, de la erosión del suelo, de la sedimentación en los cursos de agua, incluyendo también el mantenimiento o mejoramiento de la calidad del agua, de la recarga de acuíferos y de los hábitats acuáticos, entre otros. Desde el punto de vista del abastecimiento humano se pueden reconocer las principales fuentes de agua para beber, cocinar, asearse y cultivar en zonas donde las precipitaciones son insuficientes, además de generar energía eléctrica para manufacturar diversos productos, como así también ser fuente de alimentos. Asimismo, desde el punto de vista hidrológico, cumplen un rol en el ciclo global del agua ya que junto con los acuíferos subterráneos acumulan la precipitación que es conducida por escurrimientos hacia el mar, desde donde continúa el ciclo hidrológico. Cabe resaltar que los humedales y las planicies de inundación de los ríos absorben el agua de lluvia, reducen el escurrimientos disminuyendo así de los daños por inundaciones y ayudan a la recarga de aguas subterráneas contribuyendo también a mitigar las sequías. Asimismo considerando los aspectos culturales cumplen un importante rol en actividades de recreación, además de proporcionar beneficios estéticos, educativos y espirituales. Atendiendo la conservación de la biodiversidad desempeñan un papel destacado como proveedores de hábitats para diversas especies de flora y fauna, constituyendo reservorios ricos en diversidad genética (Brauman et al., 2007, Brauman, 2015, Thorp et al., 2013).Hydrological ecosystem services involve the regulation of water flows, the reduction of the flooding impact, the soil erosion and the sediment accumulation in the watercourses, also including the maintenance and improvement of the water quality, the aquiferous recharge and the aquatic habitats. The impermeability of the soil due to urbanization, the acceleration of drainings, the building of obstacles to the water flow in streams and rivers together with pollution are recognized as the main causes contributing to magnify the consequences of storms in urban and suburban areas. With the aim of showing the consequences of this type of interferences and the lossesin services and goods of the Pampean plain water flows, the case of the Gato stream is here explained. Its basin is inhabited by over 400,000 people, with approximately 50% of urbanized area and a deficient drainage system. The occupation of the alluvial valley and the lack of an integral plan for flooding risks are acknowleged as the main causes for the recurrent floods in this basin. The extreme expression of these events was observed on 2nd and 3rd April, 2013, as a consequence of a meteorological phenomenon which reached over 301 mm of water in four hours with an average intensity of 100.3 mm/h, causing the death of 89 people and over 2200 evacuated people together with an immense material loss. A study carried out in three areas of the basin, in order to identify the main causes that reduce the ecological quality of the stream, revealed that in sectors of the mid and low basin there is a deficient water quality with habitat destruction and the consequent loss of biodiversity. On the other hand, a detailed analysis of a fluvial overflow swamp, located on the upper basin, demonstrated the capacity of these areas of the basin which contribute to the improvement of water quality functioning as green filters and generating a proper environment to host diverse flora and fauna. They also retain water during storms and favor the regulation of the increase of the downstream flow contributing to alleviate the effects of floods. The review of the draining management techniques of the basin is essential. It is, therefore, necessary to count with the integral knowledge of the structure and functioning of the different areas of the basin. It is also very important to make the population aware of the necessity of their contribution, in order to regain the ecosystem services which have been partially or completely lost

La puesta en valor de los servicios ecosistémicos que ofrecen los arroyos de llanura como una medida de mitigación de las inundaciones: el caso del A° del Gato en el partido de La Plata

El concepto de servicios ecosistémicos surge en la década de los 70 como una forma de dar a conocer a la sociedad y a los tomadores de decisiones el vínculo directo que existe entre el bienestar humano y el mantenimiento de las funciones básicas del planeta. Más específicamente los servicios ecosistémicos hidrológicos se relacionan con la conservación de las cuencas hidrográficas entre los que se reconocen la regulación de flujos hidrológicos, reducción del impacto de las inundaciones, de la erosión del suelo, de la sedimentación en los cursos de agua, incluyendo también el mantenimiento o mejoramiento de la calidad del agua, de la recarga de acuíferos y de los hábitats acuáticos, entre otros. Desde el punto de vista del abastecimiento humano se pueden reconocer las principales fuentes de agua para beber, cocinar, asearse y cultivar en zonas donde las precipitaciones son insuficientes, además de generar energía eléctrica para manufacturar diversos productos, como así también ser fuente de alimentos. Asimismo, desde el punto de vista hidrológico, cumplen un rol en el ciclo global del agua ya que junto con los acuíferos subterráneos acumulan la precipitación que es conducida por escurrimientos hacia el mar, desde donde continúa el ciclo hidrológico. Cabe resaltar que los humedales y las planicies de inundación de los ríos absorben el agua de lluvia, reducen el escurrimientos disminuyendo así de los daños por inundaciones y ayudan a la recarga de aguas subterráneas contribuyendo también a mitigar las sequías. Asimismo considerando los aspectos culturales cumplen un importante rol en actividades de recreación, además de proporcionar beneficios estéticos, educativos y espirituales. Atendiendo la conservación de la biodiversidad desempeñan un papel destacado como proveedores de hábitats para diversas especies de flora y fauna, constituyendo reservorios ricos en diversidad genética (Brauman et al., 2007, Brauman, 2015, Thorp et al., 2013).Hydrological ecosystem services involve the regulation of water flows, the reduction of the flooding impact, the soil erosion and the sediment accumulation in the watercourses, also including the maintenance and improvement of the water quality, the aquiferous recharge and the aquatic habitats. The impermeability of the soil due to urbanization, the acceleration of drainings, the building of obstacles to the water flow in streams and rivers together with pollution are recognized as the main causes contributing to magnify the consequences of storms in urban and suburban areas. With the aim of showing the consequences of this type of interferences and the lossesin services and goods of the Pampean plain water flows, the case of the Gato stream is here explained. Its basin is inhabited by over 400,000 people, with approximately 50% of urbanized area and a deficient drainage system. The occupation of the alluvial valley and the lack of an integral plan for flooding risks are acknowleged as the main causes for the recurrent floods in this basin. The extreme expression of these events was observed on 2nd and 3rd April, 2013, as a consequence of a meteorological phenomenon which reached over 301 mm of water in four hours with an average intensity of 100.3 mm/h, causing the death of 89 people and over 2200 evacuated people together with an immense material loss. A study carried out in three areas of the basin, in order to identify the main causes that reduce the ecological quality of the stream, revealed that in sectors of the mid and low basin there is a deficient water quality with habitat destruction and the consequent loss of biodiversity. On the other hand, a detailed analysis of a fluvial overflow swamp, located on the upper basin, demonstrated the capacity of these areas of the basin which contribute to the improvement of water quality functioning as green filters and generating a proper environment to host diverse flora and fauna. They also retain water during storms and favor the regulation of the increase of the downstream flow contributing to alleviate the effects of floods. The review of the draining management techniques of the basin is essential. It is, therefore, necessary to count with the integral knowledge of the structure and functioning of the different areas of the basin. It is also very important to make the population aware of the necessity of their contribution, in order to regain the ecosystem services which have been partially or completely lost.Instituto de Limnología "Dr. Raúl A. Ringuelet

La puesta en valor de los servicios ecosistémicos que ofrecen los arroyos de llanura como una medida de mitigación de las inundaciones : El caso del Arroyo del Gato en el partido de La Plata

Fil: Gómez, Nora. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Instituto de Limnología Dr. Raúl A. Ringuelet; ArgentinaFil: Rodrigues Capítulo, Alberto. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Instituto de Limnología Dr. Raúl A. Ringuelet; ArgentinaFil: Colautti, Darío César. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Instituto de Limnología Dr. Raúl A. Ringuelet; ArgentinaFil: Mariñelarena, Alejandro J.. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Instituto de Limnología Dr. Raúl A. Ringuelet; ArgentinaFil: Licursi, Magdalena. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Instituto de Limnología Dr. Raúl A. Ringuelet; ArgentinaFil: Cochero, Joaquín. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Instituto de Limnología Dr. Raúl A. Ringuelet; ArgentinaFil: Armendariz, Laura Cecila. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Instituto de Limnología Dr. Raúl A. Ringuelet; ArgentinaFil: Maroñas, Miriam Edith. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Instituto de Limnología Dr. Raúl A. Ringuelet; ArgentinaFil: Donadelli, Jorge L.. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Instituto de Limnología Dr. Raúl A. Ringuelet; ArgentinaFil: Jensen, Roberto F.. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Instituto de Limnología Dr. Raúl A. Ringuelet; ArgentinaFil: García de Souza, Javier Ricardo. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Instituto de Limnología Dr. Raúl A. Ringuelet; ArgentinaFil: Maiztegui, Tomás. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Instituto de Limnología Dr. Raúl A. Ringuelet; ArgentinaFil: García, Ignacio. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Instituto de Limnología Dr. Raúl A. Ringuelet; ArgentinaFil: Sathicq, María Belén. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Instituto de Limnología Dr. Raúl A. Ringuelet; ArgentinaFil: Suarez, Jimena Camila. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Instituto de Limnología Dr. Raúl A. Ringuelet; ArgentinaFil: Cortese, Bianca. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Instituto de Limnología Dr. Raúl A. Ringuelet; Argentin

Progressive multifocal leukoencephalopathy genetic risk variants for pharmacovigilance of immunosuppressant therapies

BackgroundProgressive multifocal leukoencephalopathy (PML) is a rare and often lethal brain disorder caused by the common, typically benign polyomavirus 2, also known as JC virus (JCV). In a small percentage of immunosuppressed individuals, JCV is reactivated and infects the brain, causing devastating neurological defects. A wide range of immunosuppressed groups can develop PML, such as patients with: HIV/AIDS, hematological malignancies (e.g., leukemias, lymphomas, and multiple myeloma), autoimmune disorders (e.g., psoriasis, rheumatoid arthritis, and systemic lupus erythematosus), and organ transplants. In some patients, iatrogenic (i.e., drug-induced) PML occurs as a serious adverse event from exposure to immunosuppressant therapies used to treat their disease (e.g., hematological malignancies and multiple sclerosis). While JCV infection and immunosuppression are necessary, they are not sufficient to cause PML.MethodsWe hypothesized that patients may also have a genetic susceptibility from the presence of rare deleterious genetic variants in immune-relevant genes (e.g., those that cause inborn errors of immunity). In our prior genetic study of 184 PML cases, we discovered 19 candidate PML risk variants. In the current study of another 152 cases, we validated 4 of 19 variants in both population controls (gnomAD 3.1) and matched controls (JCV+ multiple sclerosis patients on a PML-linked drug ≥ 2 years).ResultsThe four variants, found in immune system genes with strong biological links, are: C8B, 1-57409459-C-A, rs139498867; LY9 (alias SLAMF3), 1-160769595-AG-A, rs763811636; FCN2, 9-137779251-G-A, rs76267164; STXBP2, 19-7712287-G-C, rs35490401. Carriers of any one of these variants are shown to be at high risk of PML when drug-exposed PML cases are compared to drug-exposed matched controls: P value = 3.50E-06, OR = 8.7 [3.7–20.6]. Measures of clinical validity and utility compare favorably to other genetic risk tests, such as BRCA1 and BRCA2 screening for breast cancer risk and HLA-B*15:02 pharmacogenetic screening for pharmacovigilance of carbamazepine to prevent Stevens-Johnson Syndrome and Toxic Epidermal Necrolysis.ConclusionFor the first time, a PML genetic risk test can be implemented for screening patients taking or considering treatment with a PML-linked drug in order to decrease the incidence of PML and enable safer use of highly effective therapies used to treat their underlying disease

Integrating education for sustainable development into a higher education institution: beginning the journey

Much of the current literature on integrating sustainability into HEIs is focussed on why HEIs should embrace sustainable development (SD) and what is still missing or hindering work and the integration of efforts. There is much less exploration of how SD has been interpreted at the individual HEI level and action taken as a result. This case study reflects on important elements of the journey Nottingham Trent University (NTU) in the UK has taken to integrate sustainability, focussing on key decisions and activity in 2009/10. In highlighting this, the authors seek to empower those looking to support and/or lead the embedding of Education for Sustainable Development (ESD), separately or as part of an integrated effort, in their own institution. Today in 2019, NTU is a global leader in integrating ESD as part of a wider SD agenda. The work which this paper presents, to understand and establish a baseline of key elements of NTU’s existing ESD activity and systems, was an important turning point. Activities undertaken to review and assess ‘where are we now?’, primarily through an institution-wide survey in 2009/10, led to important insights and supported dialogue, as well as the connection and underpinning of core administrative elements of the NTU SD framework and systems. Further recommendations are given in the final section of this paper on other drivers that can help to embed ESD within an HEI