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Since its introduction in Spain in 2004, Aedes albopictus has rapidly spread across the country. Its aggressive biting behaviour causes nuisance, limiting outdoor activities. Also, its role as a vector of several arboviruses implies a major public health risk, with several cases of autochthonous dengue having been reported nationwide over the past few years. Control strategies usually focus on interventions in breeding sites. As such, accurate knowledge of the main larval habitats becomes a major priority in infested areas. A detailed identification of breeding sites of Ae. albopictus was carried out in the outdoors of 60 residential properties during July-August 2022 in El Vedat de Torrent (Valencia, Eastern Spain), an area recently colonised by this species. A total of 1444 real and potential breeding sites were examined. The most abundant potential larval habitat were plant pot plates (6.48 units/house), although a low infestation level was found, both for larvae (2.06% positivity, xÌ = 30.5 larvae/container), and pupae (0.51%, xÌ = 2.5 pupae/container). A total of 7715 larvae and 205 pupae were found in a disused flooded water pool depuration system. Animal drinkers, buckets and irrigation water containers were found to be the most common positive containers. No statistical difference was observed among the different container materials. A general statistical increase of 1 larva per 11.7 ml of water in breeding sites was detected. Breeding sites of other species such as Culex pipiens (n = 2) and Culex modestus (n = 1) were also rarely found in this residential area. To our knowledge, this is the first aedic index study carried out in Europe, and it provides valuable information about the main domestic breeding habitats of Ae. albopictus, which can greatly improve control programmes.
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The central nervous system (CNS) of Drosophila is comprised of the brain and the ventral nerve cord (VNC), which are the homologous structures of the vertebrate brain and the spinal cord, respectively. Neurons of the CNS arise from neural stem cells called neuroblasts (NBs). Each neuroblast gives rise to a specific repertory of cell types whose fate is unknown in most lineages. A combination of spatial and temporal genetic cues defines the fate of each neuron. We studied the origin and specification of a group of peptidergic neurons present in several abdominal segments of the larval VNC that are characterized by the expression of the neuropeptide GPB5, the GPB5-expressing neurons (GPB5-ENs). Our data reveal that the progenitor NB that generates the GPB5-ENs also generates the abdominal leucokinergic neurons (ABLKs) in two different temporal windows. We also show that these two set of neurons share the same axonal projections in larvae and in adults and, as previously suggested, may both function in hydrosaline regulation. Our genetic analysis of potential specification determinants reveals that Klumpfuss (klu) and huckebein (hkb) are involved in the specification of the GPB5 cell fate. Additionally, we show that GPB5-ENs have a role in starvation resistance and longevity; however, their role in desiccation and ionic stress resistance is not as clear. We hypothesize that the neurons arising from the same neuroblast lineage are both architecturally similar and functionally related.
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Sistema Nervioso Central/metabolismo , Neuronas/metabolismo , Neuropéptidos/metabolismo , Animales , Modelos Animales de Enfermedad , Drosophila melanogaster , RatasRESUMEN
Hexokinase 2 (Hxk2) fromSaccharomyces cerevisiaeis a bi-functional enzyme, being both a catalyst in the cytosol and an important regulator of the glucose repression signal in the nucleus. Despite considerable recent progress, little is known about the regulatory mechanism that controls nuclear Hxk2 association with theSUC2promoter chromatin and how this association is necessary forSUC2gene repression. Our data indicate that in theSUC2promoter context, Hxk2 functions through a variety of structurally unrelated factors, mainly the DNA-binding Mig1 and Mig2 repressors and the regulatory Snf1 and Reg1 factors. Hxk2 sustains the repressor complex architecture maintaining transcriptional repression at theSUC2gene. Using chromatin immunoprecipitation assays, we discovered that the Hxk2 in its open configuration, at low glucose conditions, leaves the repressor complex that induces its dissociation and promotesSUC2gene expression. In high glucose conditions, Hxk2 adopts a close conformation that promotes Hxk2 binding to the Mig1 protein and the reassembly of theSUC2repressor complex. Additional findings highlight the possibility that Hxk2 constitutes an intracellular glucose sensor that operates by changing its conformation in response to cytoplasmic glucose levels that regulate its interaction with Mig1 and thus its recruitment to the repressor complex of theSUC2promoter. Thus, our data indicate that Hxk2 is more intimately involved in gene regulation than previously thought.
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Glucosa/metabolismo , Hexoquinasa/metabolismo , Complejos Multiproteicos/metabolismo , Proteínas Represoras/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/metabolismo , Glucosa/genética , Hexoquinasa/genética , Complejos Multiproteicos/genética , Unión Proteica , Proteína Fosfatasa 1/genética , Proteína Fosfatasa 1/metabolismo , Proteínas Serina-Treonina Quinasas/genética , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Represoras/genética , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/biosíntesis , Proteínas de Saccharomyces cerevisiae/genética , beta-Fructofuranosidasa/biosíntesis , beta-Fructofuranosidasa/genéticaRESUMEN
Although the Hox genes are the main factors involved in the generation of diversity along the anterior/posterior body axis of segmented organisms, it is still largely unknown how these genes act in single cells to determine specific traits at precise developmental stages. The aim of this study was to understand the mechanisms by which Hox genes of the Bithorax complex (Bx-C) of Drosophila act to define segmental differences in the ventral nerve cord of the central nervous system. To achieve this, we have focused on the specification of the leucokinin-expressing neurons. We find that these neurons are specified from the same progenitor neuroblast at two different developmental stages: embryonic and larval neurogenesis. We show that genes of the Bx-C acted in postmitotic cells to specify the segment-specific appearance of leucokinergic cells in the larval and adult ventral nerve cord.
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Drosophila melanogaster/embriología , Regulación del Desarrollo de la Expresión Génica , Proteínas de Homeodominio/metabolismo , Sistema Nervioso/embriología , Animales , Tipificación del Cuerpo , Linaje de la Célula , Sistema Nervioso Central/embriología , Sistema Nervioso Central/metabolismo , Cruzamientos Genéticos , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/genética , Genotipo , Inmunohistoquímica , Neuropéptidos/metabolismo , Fenotipo , Células Madre/citología , Factores de TiempoRESUMEN
Type 2 diabetes, obesity, and sex difference affect myocardial glucose uptake and utilization. However, their effect on the intramyocellular fate of glucose in humans has been unknown. How the heart uses glucose is important, because it affects energy production and oxygen efficiency, which in turn affect heart function and adaptability. We hypothesized that type 2 diabetes, sex difference, and obesity affect myocardial glucose oxidation, glycolysis, and glycogen production. In a first-in-human study, we measured intramyocardiocellular glucose metabolism from time-activity curves generated from previously obtained positron emission tomography scans of 110 subjects in 3 groups: nonobese, obese, and diabetes. Group and sex difference interacted in the prediction of all glucose uptake, utilization, and metabolism rates. Group independently predicted fractional glucose uptake and its components: glycolysis, glycogen deposition, and glucose oxidation rates. Sex difference predicted glycolysis rates. However, there were fewer differences in glucose metabolism between diabetic patients and others when plasma glucose levels were included in the modeling. The potentially detrimental effects of obesity and diabetes on myocardial glucose metabolism are more pronounced in men than women. This sex difference dimorphism needs to be taken into account in the design, trials, and application of metabolic modulator therapy. Slightly higher plasma glucose levels improve depressed glucose oxidation and glycogen deposition rates in diabetic patients.
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Glucemia/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Metabolismo Energético , Miocardio/metabolismo , Obesidad/metabolismo , Adulto , Anciano , Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/diagnóstico por imagen , Diabetes Mellitus Tipo 2/fisiopatología , Femenino , Glucógeno/metabolismo , Glucólisis , Hemodinámica , Humanos , Cinética , Masculino , Persona de Mediana Edad , Obesidad/sangre , Obesidad/diagnóstico por imagen , Obesidad/fisiopatología , Oxidación-Reducción , Tomografía de Emisión de Positrones , Factores Sexuales , Adulto JovenRESUMEN
BACKGROUND: The Drosophila central nervous system contains many types of neurons that are derived from a limited number of progenitors as evidenced in the ventral ganglion. The situation is much more complex in the developing brain. The main neuronal structures in the adult brain are generated in the larval neurogenesis, although the basic neuropil structures are already laid down during embryogenesis. The embryonic factors involved in adult neuron origin are largely unknown. To shed light on how brain cell diversity is achieved, we studied the early temporal and spatial cues involved in the specification of lateral horn leucokinin peptidergic neurons (LHLKs). RESULTS: Our analysis revealed that these neurons have an embryonic origin. We identified their progenitor neuroblast as Pcd6 in the Technau and Urbach terminology. Evidence was obtained that a temporal series involving the transcription factors Kr, Pdm, and Cas participates in the genesis of the LHLK lineage, the Castor window being the one in which the LHLKs neurons are generated. It was also shown that Notch signalling and Dimmed are involved in the specification of the LHLKs. CONCLUSIONS: Serial homologies with the origin and factors involved in specification of the abdominal leucokinergic neurons (ABLKs) have been detected.
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Encéfalo , Proteínas de Drosophila/biosíntesis , Regulación del Desarrollo de la Expresión Génica/fisiología , Células-Madre Neurales/metabolismo , Neurogénesis/fisiología , Neurópilo , Factores de Transcripción/biosíntesis , Animales , Encéfalo/citología , Encéfalo/embriología , Proteínas de Drosophila/genética , Drosophila melanogaster , Células-Madre Neurales/citología , Neurópilo/citología , Neurópilo/metabolismo , Factores de Transcripción/genéticaRESUMEN
Nucleocytoplasmic shuttling of Hxk2 induced by glucose levels has been reported recently. Here we present evidence that indicates that Hxk2 nucleocytoplasmic traffic is regulated by phosphorylation and dephosphorylation at serine 14. Moreover, we identified the protein kinase Snf1 and the protein phosphatase Glc7-Reg1 as novel regulatory partners for the nucleocytoplasmic shuttling of Hxk2. Functional studies revealed that, in contrast to the wild-type protein, the dephosphorylation-mimicking mutant of Hxk2 retains its nuclear localization in low glucose conditions, and the phosphomimetic mutant of Hxk2 retains its cytoplasmic localization in high glucose conditions. Interaction experiments of Hxk2 with Kap60 and Xpo1 indicated that nuclear import of the S14D mutant of Hxk2 is severely decreased but that the export is significantly enhanced. Conversely, nuclear import of the S14A mutant of Hxk2 was significantly enhanced, although the export was severely decreased. The interaction of Hxk2 with Kap60 and Xpo1 was found to occur in the dephosphorylated and phosphorylated states of the protein, respectively. In addition, we found that Hxk2 is a substrate for Snf1. Mutational analysis indicated that serine 14 is a major in vitro and in vivo phosphorylation site for Snf1. We also provide evidence that dephosphorylation of Hxk2 at serine 14 is a protein phosphatase Glc7-Reg1-dependent process. Taken together, this study establishes a functional link between Hxk2, Reg1, and Snf1 signaling, which involves the regulation of Hxk2 nucleocytoplasmic shuttling by phosphorylation-dephosphorylation of serine 14.
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Núcleo Celular/enzimología , Citoplasma/enzimología , Hexoquinasa/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/enzimología , Transporte Activo de Núcleo Celular/fisiología , Sustitución de Aminoácidos , Núcleo Celular/genética , Citoplasma/genética , Hexoquinasa/genética , Carioferinas/genética , Carioferinas/metabolismo , Mutación Missense , Fosforilación/fisiología , Proteína Fosfatasa 1/genética , Proteína Fosfatasa 1/metabolismo , Proteínas Serina-Treonina Quinasas/genética , Proteínas Serina-Treonina Quinasas/metabolismo , Receptores Citoplasmáticos y Nucleares/genética , Receptores Citoplasmáticos y Nucleares/metabolismo , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/genética , Transducción de Señal/fisiología , Proteína Exportina 1RESUMEN
Hexokinase 2 (Hxk2) from Saccharomyces cerevisiae was one of the first metabolic enzymes described as a multifunctional protein. Hxk2 has a double subcellular localization and role, it functions as a glycolytic enzyme in the cytoplasm and as a regulator of gene transcription of several Mig1-regulated genes in the nucleus. However, the mechanism by which Hxk2 enters in the nucleus was unknown until now. Here, we report that the Hxk2 protein is an import substrate of the carriers α-importin (Kap60 in yeast) and ß-importin (Kap95 in yeast). We also show that the Hxk2 nuclear import and the binding of Hxk2 with Kap60 are glucose-dependent and involve one lysine-rich nuclear localization sequence (NLS), located between lysine 6 and lysine 12. Moreover, Kap95 facilitates the recognition of the Hxk2 NLS1 motif by Kap60 and both importins are essential for Hxk2 nuclear import. It is also demonstrated that Hxk2 nuclear import and its binding to Kap95 and Kap60 depend on the Gsp1-GTP/GDP protein levels. Thus, our study uncovers Hxk2 as a new cargo for the α/ß-importin pathway of S. cerevisiae.
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Núcleo Celular/metabolismo , Hexoquinasa/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/metabolismo , Factores de Transcripción/metabolismo , alfa Carioferinas/metabolismo , beta Carioferinas/metabolismo , Transporte Activo de Núcleo Celular/fisiología , Secuencias de Aminoácidos , Núcleo Celular/genética , Guanosina Difosfato/genética , Guanosina Difosfato/metabolismo , Guanosina Trifosfato/genética , Guanosina Trifosfato/metabolismo , Hexoquinasa/genética , Proteínas de Unión al GTP Monoméricas/genética , Proteínas de Unión al GTP Monoméricas/metabolismo , Señales de Localización Nuclear/genética , Señales de Localización Nuclear/metabolismo , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Proteínas Represoras/genética , Proteínas Represoras/metabolismo , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/genética , Factores de Transcripción/genética , alfa Carioferinas/genética , beta Carioferinas/genéticaRESUMEN
Increased myocardial lipid delivery is a determinant of myocardial substrate metabolism and function in animal models of type 2 diabetes (T2DM). Sex also has major effects on myocardial metabolism in the human heart. Our aims were to determine whether 1) sex affects the myocardial metabolic response to lipid lowering in T2DM, 2) altering lipid [fatty acid (FA) or triglyceride] delivery to the heart would lower the elevated myocardial lipid metabolism associated with T2DM, and 3) decreasing lipid delivery improves diastolic dysfunction in T2DM. To this end, we studied 78 T2DM patients (43 women) with positron emission tomography, echocardiography, and whole body tracer studies before and 3 mo after randomization to metformin (MET), metformin + rosiglitazone (ROSI), or metformin + Lovaza (LOV). No treatment main effects were found for myocardial substrate metabolism, partly because men and women often had different responses to a given treatment. In men, MET decreased FA clearance, which was linked to increased plasma FA levels, myocardial FA utilization and oxidation, and lower myocardial glucose utilization. In women, ROSI increased FA clearance, thereby decreasing plasma FA levels and myocardial FA utilization. Although LOV did not change triglyceride levels, it improved diastolic function, particularly in men. Group and sex also interacted in determining myocardial glucose uptake. Thus, in T2DM, different therapeutic regimens impact myocardial metabolism and diastolic function in a sex-specific manner. This suggests that sex should be taken into account when designing a patient's diabetes treatment.
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Diabetes Mellitus Tipo 2/tratamiento farmacológico , Suplementos Dietéticos , Ácidos Docosahexaenoicos/uso terapéutico , Ácido Eicosapentaenoico/uso terapéutico , Metabolismo Energético/efectos de los fármacos , Ácidos Grasos Omega-3/uso terapéutico , Disparidades en el Estado de Salud , Hipoglucemiantes/uso terapéutico , Metformina/uso terapéutico , Miocardio/metabolismo , Tiazoles/uso terapéutico , Función Ventricular Izquierda/efectos de los fármacos , Análisis de Varianza , Distribución de Chi-Cuadrado , Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/fisiopatología , Diástole/efectos de los fármacos , Método Doble Ciego , Combinación de Medicamentos , Ecocardiografía Doppler , Ácidos Grasos/metabolismo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Missouri , Tomografía de Emisión de Positrones , Recuperación de la Función , Factores Sexuales , Volumen Sistólico/efectos de los fármacos , Factores de Tiempo , Resultado del Tratamiento , Triglicéridos/metabolismo , Presión Ventricular/efectos de los fármacosRESUMEN
A transmission electron microscopy study of nanogratings formed in bulk amorphous silica by direct writing with an ultrafast pulsed laser with a radiation wavelength of 1030 nm and pulse duration of 560 fs is presented. The results achieved show that the nanogratings are composed of planar nanostructures with an average periodicity of 250 nm and typical thickness of about 30 nm, consisting of alternating layers of heavily damaged material and layers of material where a dense precipitation of nanocrystals occurred. The crystallization of silica to form these nanocrystals can be explained by the large pressures and temperatures reached in these regions as a result of nanoplasma formation and recombination.
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BACKGROUND: Individuals with HIV infection and peripheral metabolic complications have impaired basal myocardial insulin sensitivity that is related to left ventricular (LV) diastolic dysfunction. It is unknown whether interventions shown to be effective in improving peripheral insulin sensitivity can improve basal myocardial insulin sensitivity and diastolic function in people with HIV and peripheral metabolic complications. OBJECTIVE: In a pilot study, we evaluated whether the peroxisome proliferator-activated receptor-gamma (PPAR-γ) agonist pioglitazone or combined endurance and resistance exercise training improves basal myocardial insulin sensitivity and diastolic function in HIV+ adults with peripheral metabolic complications. DESIGN: Twenty-four HIV+ adults with metabolic complications including peripheral insulin resistance were randomly assigned to 4 months of pioglitazone (PIO; 30 mg/d) or supervised, progressive endurance and resistance exercise training (EXS; 90-120 min/d, 3 d/wk). Basal myocardial substrate metabolism was quantified by radioisotope tracer methodology and positron emission tomography (PET) imaging, and LV function was measured by echocardiography. RESULTS: Twenty participants completed the study. Neither PIO nor EXS resulted in a detectable improvement in basal myocardial insulin sensitivity or diastolic function. Post hoc analyses revealed sample sizes of more than 100 participants are needed to detect significant effects of these interventions on basal myocardial insulin sensitivity and function. CONCLUSIONS: PIO or EXS alone did not significantly increase basal myocardial insulin sensitivity or LV diastolic function in HIV+ individuals with peripheral metabolic complications.
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Ejercicio Físico , Infecciones por VIH/complicaciones , Hipoglucemiantes/uso terapéutico , Miocardio/metabolismo , Tiazolidinedionas/uso terapéutico , Función Ventricular Izquierda/fisiología , Adulto , Femenino , Infecciones por VIH/metabolismo , Infecciones por VIH/fisiopatología , Humanos , Resistencia a la Insulina/fisiología , Masculino , Proyectos Piloto , Pioglitazona , Estudios ProspectivosRESUMEN
Considering that teleworking and online training are on the rise following the pandemic, studying how school-life balance affects the development of VET competences in online learning during COVID-19 can provide relevant information to enhance educational equity in the future. A longitudinal study was conducted employing an on-line questionnaire to meet the following aims: to explore the development of cross-disciplinary competences in VET during COVID-19; to identify different students' profiles according to their school-life balance during the pandemic; and, to analyse whether the school-life balance was affecting competency development and propose improvements to training as a result. Results show that cross-disciplinary competences did not undergo important changes between the pre-pandemic scenario and during it, except for a decrease in metacognitive self-regulation. Similarly, most students reported having spent the same time studying before and during the pandemic. However, three main profiles of students are revealed, highlighting certain school-life imbalances. While all agree that remote teaching was critical in coping with the situation, differences were found by age and gender, with some participants experiencing more challenging situations. These results provide a fertile context for VET designers and teachers to generate new learning scenarios that meet all students' potential needs. Supplementary Information: The online version contains supplementary material available at 10.1007/s12186-023-09314-1.
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Asthma is a chronic respiratory disease with a high health, social and economic impact, particularly in the case of Severe Uncontrolled Asthma (SUA). For this reason, new strategies are especially necessary to improve its approach, with a personalized approach to each patient and from a multidisciplinary perspective, in addition to integrating the new telemedicine and telepharmacy practices promoted as a result of the COVID-19 pandemic. In this context, the TEAM 2.0 project ("Work in Multidisciplinary Asthma Teams") has been developed, following the TEAM project carried out in 2019, with the aim of updating and prioritizing good multidisciplinary work practices in SUA in a post pandemic context and analyze the progress made. A coordinating group, made up of eight multidisciplinary teams of hospital pharmacists, pulmonologists, and allergists, carried out an updated bibliographic review, sharing of good multidisciplinary practices, and analysis of advances. Through five regional meetings with other experts with experience in SUA, the good practices identified were shared and subjected to debate, evaluation and prioritization. In total, 23 good multidisciplinary work practices in SUA, grouped into five work areas: 1) Organization of work in multidisciplinary teams, 2) Patient education, self-management and adherence, 3) Health results, data monitoring and persistence, 4) Telepharmacy and experiences implemented during the COVID-19 pandemic and 5) Training and research, were evaluated and prioritized by 57 professionals from the field of Hospital Pharmacy, Pulmonology, Allergology and Nursing. This work has made it possible to update the roadmap of priority actions to continue advancing in optimal models of care for patients with AGNC in a post-COVID-19 context.
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Asma , COVID-19 , Humanos , Pandemias , Farmacéuticos , Asma/terapia , Grupo de Atención al PacienteRESUMEN
Asthma is a chronic respiratory disease with a high health, social and economic impact, particularly in the case of Severe Uncontrolled Asthma (SUA). For this reason, new strategies are especially necessary to improve its approach, with a personalized approach to each patient and from a multidisciplinary perspective, in addition to integrating the new telemedicine and telepharmacy practices promoted as a result of the COVID-19 pandemic. In this context, the TEAM 2.0 project ("Work in Multidisciplinary Asthma Teams") has been developed, following the TEAM project carried out in 2019, with the aim of updating and prioritizing good multidisciplinary work practices in SUA in a post pandemic context and analyze the progress made. A coordinating group, made up of eight multidisciplinary teams of hospital pharmacists, pulmonologists, and allergists, carried out an updated bibliographic review, sharing of good multidisciplinary practices, and analysis of advances. Through five regional meetings with other experts with experience in SUA, the good practices identified were shared and subjected to debate, evaluation and prioritization. In total, 23 good multidisciplinary work practices in SUA, grouped into five work areas: 1) Organization of work in multidisciplinary teams, 2) Patient education, self-management and adherence, 3) Health results, data monitoring and persistence, 4) Telepharmacy and experiences implemented during the COVID-19 pandemic and 5) Training and research, were evaluated and prioritized by 57 professionals from the field of Hospital Pharmacy, Pulmonology, Allergology and Nursing. This work has made it possible to update the roadmap of priority actions to continue advancing in optimal models of care for patients with AGNC in a post-COVID-19 context.
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Asma , COVID-19 , Humanos , Pandemias , Farmacéuticos , Asma/terapia , Grupo de Atención al PacienteRESUMEN
BACKGROUND: Mig2 has been described as a transcriptional factor that in the absence of Mig1 protein is required for glucose repression of the SUC2 gene. Recently it has been reported that Mig2 has two different subcellular localizations. In high-glucose conditions it is a nuclear modulator of several Mig1-regulated genes, but in low-glucose most of the Mig2 protein accumulates in mitochondria. Thus, the Mig2 protein enters and leaves the nucleus in a glucose regulated manner. However, the mechanism by which Mig2 enters into the nucleus was unknown until now. RESULTS: Here, we report that the Mig2 protein is an import substrate of the carrier Kap95 (importin-ß). The Mig2 nuclear import mechanism bypasses the requirement for Kap60 (importin-α) as an adaptor protein, since Mig2 directly binds to Kap95 in the presence of Gsp1(GDP). We also show that the Mig2 nuclear import and the binding of Mig2 with Kap95 are not glucose-dependent processes and require a basic NLS motif, located between lysine-32 and arginine-37. Mig2 interaction with Kap95 was assessed in vitro using purified proteins, demonstrating that importin-ß, together with the GTP-binding protein Gsp1, is able to mediate efficient Mig2-Kap95 interaction in the absence of the importin-α (Kap60). It was also demonstrated, that the directionality of Mig2 transport is regulated by association with the small GTPase Gsp1 in the GDP- or GTP-bound forms, which promote cargo recognition and release, respectively. CONCLUSIONS: The Mig2 protein accumulates in the nucleus through a Kap95 and NLS-dependent nuclear import pathway, which is independent of importin-α in Saccharomyces cerevisiae.
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Proteínas Represoras/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/metabolismo , beta Carioferinas/metabolismo , Transporte Activo de Núcleo Celular , Secuencias de Aminoácidos , Núcleo Celular/metabolismo , Carioferinas/metabolismo , Proteínas de Unión al GTP Monoméricas/metabolismo , Mutación , Proteínas Nucleares/metabolismo , Unión Proteica , Proteínas Represoras/química , Proteínas de Saccharomyces cerevisiae/química , alfa Carioferinas/genética , alfa Carioferinas/metabolismo , beta Carioferinas/genéticaRESUMEN
Understanding vocational learning and transfer is vital to European citizens. We need to understand how transfer works, which factors influence it, and how these factors affect employee behaviour. Research in online training specific to Southern Europe is needed to move the field forward. The Unified Model of Motivation for Training Transfer (MTT) was proposed to understand behaviour change after training. It conceives three phases: (1) forming transfer intentions, (2) actualizing implementation intentions for transfer, and (3) strengthening transfer commitment. We analysed initial transfer intention and transfer following online training in three Spanish organisations. We used an ex post facto prospective design with one group (n = 204). We applied the online version of the Initial Transfer Intention questionnaire (ITI) three days before the training, and the Transfer Questionnaire (TrQ) three to four months after the training. Training consisted of 22 online courses offered by the three participating organisations. A cluster analysis and post hoc analysis were performed. We identified three groups (k = 3), indicating that there were significant differences in the means between employees with low and high intention to transfer. Results showed a greater difference in the factor profile between participants with LowPT and HighPT. We identified common characteristics among people with low levels of transfer; this information can help understand what type of employee will transfer less and provide cues on how to prevent this from happening in future training activities. Limitations and recommendations for research and practice are discussed.
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BACKGROUND: In the general population, peripheral metabolic complications (MC) increase the risk for left ventricular dysfunction. Human immunodeficiency virus infection (HIV) and combination anti-retroviral therapy (cART) are associated with MC, left ventricular dysfunction, and a higher incidence of cardiovascular events than the general population. We examined whether myocardial nutrient metabolism and left ventricular dysfunction are related to one another and worse in HIV infected men treated with cART vs. HIV-negative men with or without MC. METHODS: Prospective, cross-sectional study of myocardial glucose and fatty acid metabolism and left ventricular function in HIV+ and HIV-negative men with and without MC. Myocardial glucose utilization (GLUT), and fatty acid oxidation and utilization rates were quantified using 11C-glucose and 11C-palmitate and myocardial positron emission tomography (PET) imaging in four groups of men: 23 HIV+ men with MC+ (HIV+/MC+, 42 ± 6 yrs), 15 HIV+ men without MC (HIV+/MC-, 41 ± 6 yrs), 9 HIV-negative men with MC (HIV-/MC+, 33 ± 5 yrs), and 22 HIV-negative men without MC (HIV-/MC-, 25 ± 6 yrs). Left ventricular function parameters were quantified using echocardiography. RESULTS: Myocardial glucose utilization was similar among groups, however when normalized to fasting plasma insulin concentration (GLUT/INS) was lower (p < 0.01) in men with metabolic complications (HIV+: 9.2 ± 6.2 vs. HIV-: 10.4 ± 8.1 nmol/g/min/µU/mL) than men without metabolic complications (HIV+: 45.0 ± 33.3 vs. HIV-: 60.3 ± 53.0 nmol/g/min/µU/mL). Lower GLUT/INS was associated with lower myocardial relaxation velocity during early diastole (r = 0.39, p < 0.001). CONCLUSION: Men with metabolic complications, irrespective of HIV infection, had lower basal myocardial glucose utilization rates per unit insulin that were related to left ventricular diastolic impairments, indicating that well-controlled HIV infection is not an independent risk factor for blunted myocardial glucose utilization per unit of insulin. TRIAL REGISTRATION: NIH Clinical Trials NCT00656851.
Asunto(s)
Circulación Coronaria , Metabolismo Energético , Infecciones por VIH/tratamiento farmacológico , Enfermedades Metabólicas/etiología , Miocardio/metabolismo , Consumo de Oxígeno , Disfunción Ventricular Izquierda/etiología , Adulto , Análisis de Varianza , Terapia Antirretroviral Altamente Activa/efectos adversos , Biomarcadores/sangre , Estudios Transversales , Ecocardiografía , Ácidos Grasos/metabolismo , Glucosa/metabolismo , Infecciones por VIH/complicaciones , Infecciones por VIH/diagnóstico , Infecciones por VIH/metabolismo , Infecciones por VIH/fisiopatología , Humanos , Insulina/sangre , Resistencia a la Insulina , Modelos Lineales , Masculino , Enfermedades Metabólicas/diagnóstico , Enfermedades Metabólicas/metabolismo , Enfermedades Metabólicas/fisiopatología , Persona de Mediana Edad , Missouri , Análisis Multivariante , Tomografía de Emisión de Positrones , Estudios Prospectivos , Medición de Riesgo , Factores de Riesgo , Disfunción Ventricular Izquierda/diagnóstico , Disfunción Ventricular Izquierda/metabolismo , Disfunción Ventricular Izquierda/fisiopatología , Función Ventricular Izquierda , Adulto JovenRESUMEN
BACKGROUND: Because studies in animal models of type-2 diabetes mellitus (DM) show that excessive myocardial fatty acid (FA) metabolism (at the expense of glucose metabolism) cause cardiac dysfunction, we hypothesized that women with DM would have more FA and less glucose myocardial metabolism than normal or even obese (OB) women. RESEARCH DESIGN AND METHODS: Women who were lean volunteers (NV) (N = 14; age 35 ± 17 years, body mass index 23 ± 1 kg/m(2)), OB (N = 28;31 ± 6 years, BMI 39 ± 7 kg/m2), and DM (n = 22; 54 ± 11 years, BMI 38 ± 5 kg/m2) were studied. Cardiac positron emission tomography was performed for the determination of myocardial blood flow, oxygen consumption, FA and glucose metabolism. Cardiac work was measured by echocardiography and efficiency by the ratio of work to myocardial oxygen consumption. RESULTS: Fractional glucose uptake was comparable between NV and OB but lower in DM (P < .05 versus NV). Myocardial FA utilization and oxidation were both higher in DM compared with NV and OB (P < .0001). Myocardial FA utilization and oxidation had positive correlations with HOMA (R = 0.35, P = .005 and R = 0.40, P = .001, respectively) whereas fractional glucose uptake exhibited an inverse correlation (R = -.31, P = .01). Cardiac work and efficiency were similar among the three groups. CONCLUSIONS: In women, the presence of OB and DM compared with OB alone is associated with a greater reliance on myocardial FA metabolism at the expense of glucose metabolism. These perturbations in myocardial metabolism are not associated in a decline left ventricular efficiency or function suggesting that the metabolic perturbations may precede an eventual decline left ventricular function as is seen in animal models of DM.
Asunto(s)
Cardiomiopatías/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Ácidos Grasos/metabolismo , Glucosa/metabolismo , Resistencia a la Insulina , Miocardio/metabolismo , Obesidad/metabolismo , Adulto , Cardiomiopatías/complicaciones , Diabetes Mellitus Tipo 2/complicaciones , Femenino , HumanosRESUMEN
Hkx2 (hexokinase 2) from Saccharomyces cerevisiae was one of the first metabolic enzymes described as a multifunctional protein. Hxk2 has a double subcellular localization: it functions as a glycolytic enzyme in the cytoplasm and as a regulator of gene transcription of several Mig1-regulated genes in the nucleus. To get more insights into the structure-function relationships of the Hxk2 protein, we followed two different approaches. In the first, we deleted the last eight amino acids of Hxk2 and replaced Ser³°4 with phenylalanine to generate Hxk2(wca). Analysis of this mutant demonstrated that these domains play an essential role in the catalytic activity of yeast Hxk2, but has no effect on the regulatory function of this protein. In the second, we analysed whether amino acids from Lys6 to Met¹5 of Hxk2 (Hxk2(wrf)) are essential for the regulatory role of Hxk2 and whether there is an effect on the hexose kinase activity of this protein. In the present paper, we report that the Hxk2(wca) mutant protein interacts with the Mig1 transcriptional repressor and the Snf1 protein kinase in the nucleus at the level of the SUC2-Mig1 repressor complex. We have demonstrated that Hxk2(wca) maintained full regulatory function because the glucose-repression signalling of the wild-type machinery is maintained. We also report that the Hxk2(wrf) mutant allele is incapable of glucose repression signalling because it does not interact with Mig1 at the level of the SUC2-Mig1 repressor complex. The two mutants, Hxk2(wca) and Hxk2(wrf) retain single functions, as a transcriptional factor or as an enzyme with hexose-phosphorylating activity, but have lost the original bifunctionality of Hxk2.