Imaging the complexity, plasticity, and dynamics of caveolae

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Caveolae: Mechanosensing and mechanotransduction devices linking membrane trafficking to mechanoadaptation.

Mechanical forces (extracellular matrix stiffness, vascular shear stress, and muscle stretching) reaching the plasma membrane (PM) determine cell behavior. Caveolae are PM-invaginated nanodomains with specific lipid and protein composition. Being highly abundant in mechanically challenged tissues (muscles, lungs, vessels, and adipose tissues), they protect cells from mechanical stress damage. Caveolae flatten upon increased PM tension, enabling both force sensing and accommodation, critical for cell mechanoprotection and homeostasis. Thus, caveolae are highly plastic, ranging in complexity from flattened membranes to vacuolar invaginations surrounded by caveolae-rosettes-which also contribute to mechanoprotection. Caveolar components crosstalk with mechanotransduction pathways and recent studies show that they translocate from the PM to the nucleus to convey stress information. Furthermore, caveolae components can regulate membrane traffic from/to the PM to adapt to environmental mechanical forces. The interdependence between lipids and caveolae starts to be understood, and the relevance of caveolae-dependent membrane trafficking linked to mechanoadaption to different physiopathological processes is emerging.This study was supported by grants from the Spanish Ministry of Science and Innovation(MICIIN)/Agencia Estatal de Investigación (AEI)/European Regional Development Fund (ERDF/FEDER) “A way to make Europe” – (SAF2014-51876-R, SAF2017-83130-R, IGP-SO grant MINSEV1512-07-2016, CSD2009-0016 and BFU2016-81912-REDC), Comunidad Autónoma de Madrid (Tec4Bio-CM, S2018/NMT¬4443), Fundació La Marató de TV3 (385/C/2019) and the Worldwide Cancer Research Foundation (15-0404), all to M.A.d.P. We received funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement No 641639. The CNIC is supported by the Instituto de Salud Carlos III (ISCIII), the Ministerio de Ciencia e Innovación (MICIIN) and the Pro CNIC Foundation, and is a Severo Ochoa Center of Excellence (SEV-2015-0505).S

Mediciones de transitorios durante las maniobras de seccionadores en estaciones transformadoras de 500 KV

La falla o el deterioro dieléctrico de Transformadores de Intensidad (TI) en Estaciones Transformadoras (ET) de 500 kV, motivaron el estudio del tema orientado a medir uno de los tipos de solicitaciones transitorias a las que están sometidos los TI en las playas de las ET. Los transitorios medidos y presentados en el presente trabajo son los que se manifiestan durante la maniobra de apertura y cierre de seccionadores. Para la medición de los transitorios de tensión generados en las barras, se emplearon sensores de campo eléctrico que no requieren ninguna vinculación galvánica con las barras de la ET. Este método de medición resulta innovador, dado que su modalidad de sensado de campo permite compatibilizar el gran ancho de banda de medición requerido, con la contaminación electromagnética existente en la playa de la ET. Además es posible la instalación de los sensores sin producir cortes de energía en la ET. Se midieron los transitorios generados en dos bahías de dos ET. Cada una de las bahías poseía distintos tipos de seccionadores. Dada la versatilidad de los casos en los que se registraron los transitorios de las maniobras de los seccionadores, es posible indicar que se cubrieron los casos usuales en arreglos de 500 kV para interruptor y medio. En los registros fue posible encontrar las características de las solicitaciones que inciden en los TI, representadas por las amplitudes de tensión, tiempos de frente, duración y cantidad de reencendidos de arcos. Conociendo las solicitaciones que se generan en las barras, será posible determinar las corrientes impulsivas que inciden en los TI asociados a la barra. La captación de los transitorios mediante la medición del campo eléctrico generado, ha sido la base que posibilitó obtener, con la apropiada respuesta, el detalle del fenómeno generado por el reencendido de arcos. Tanto los sensores de campo eléctrico, fibras ópticas, transductores y registradores resultan de un reducido tamaño y peso, factores que facilitan su transporte hasta el sitio de uso y su correspondiente instalación. La selección adecuada de los componentes en la construcción de sensores, transductores y otras partes del equipamiento de captación, ha permitido implementar un sistema que registra con 10 MHz de ancho de banda.Instituto de Investigaciones Tecnológicas para Redes y Equipos Eléctricos (IITREE

Mediciones de transitorios durante las maniobras de seccionadores en estaciones transformadoras de 500 KV

La falla o el deterioro dieléctrico de Transformadores de Intensidad (TI) en Estaciones Transformadoras (ET) de 500 kV, motivaron el estudio del tema orientado a medir uno de los tipos de solicitaciones transitorias a las que están sometidos los TI en las playas de las ET. Los transitorios medidos y presentados en el presente trabajo son los que se manifiestan durante la maniobra de apertura y cierre de seccionadores. Para la medición de los transitorios de tensión generados en las barras, se emplearon sensores de campo eléctrico que no requieren ninguna vinculación galvánica con las barras de la ET. Este método de medición resulta innovador, dado que su modalidad de sensado de campo permite compatibilizar el gran ancho de banda de medición requerido, con la contaminación electromagnética existente en la playa de la ET. Además es posible la instalación de los sensores sin producir cortes de energía en la ET. Se midieron los transitorios generados en dos bahías de dos ET. Cada una de las bahías poseía distintos tipos de seccionadores. Dada la versatilidad de los casos en los que se registraron los transitorios de las maniobras de los seccionadores, es posible indicar que se cubrieron los casos usuales en arreglos de 500 kV para interruptor y medio. En los registros fue posible encontrar las características de las solicitaciones que inciden en los TI, representadas por las amplitudes de tensión, tiempos de frente, duración y cantidad de reencendidos de arcos. Conociendo las solicitaciones que se generan en las barras, será posible determinar las corrientes impulsivas que inciden en los TI asociados a la barra. La captación de los transitorios mediante la medición del campo eléctrico generado, ha sido la base que posibilitó obtener, con la apropiada respuesta, el detalle del fenómeno generado por el reencendido de arcos. Tanto los sensores de campo eléctrico, fibras ópticas, transductores y registradores resultan de un reducido tamaño y peso, factores que facilitan su transporte hasta el sitio de uso y su correspondiente instalación. La selección adecuada de los componentes en la construcción de sensores, transductores y otras partes del equipamiento de captación, ha permitido implementar un sistema que registra con 10 MHz de ancho de banda.Instituto de Investigaciones Tecnológicas para Redes y Equipos Eléctricos (IITREE

Generalized erythematous scaly rash after glucocorticoids

A 65-years-old woman with a medical history of idiopathic throm- bocytopenic purpura and psoriasis in treatment with topical glucocor- ticoids presented with a three-month history of burning, generalized erythematous, scaly rash, and chills. A few weeks before the rash, the patient presented petechiae on her thighs due to a low platelet count (28.000 platelets per microliter), for which she started treatment with prednisone 25 mg/week. The rash was initially treated with topical ointments including clobetasol, urea, salicylic acid, ammonium lactate, and propylene glycol without improvement. The physical examination showed generalized erythroderma (Fig. 1A) from neck to feet (Fig. 1B), with thick silvery desquamation respecting the face and back of the legs (Fig. 1C), involving more than 90% of the patient’s body surface area and erythematous scaly plaques on the scalp. Laboratory test results were normal. A punch biopsy specimen obtained from an arm area showed increased keratinization at the level of the corneal layer with compact parakeratosis with abundant polymorphonuclear cells. The epidermis presented psoriasiform hyperplasia with significant spongio- sis. What is the diagnosis

Field measurements and modelling of high frequency transients during disconnect switch operations in EHV Substations : Assessment of their effects on Current Transformers

The article describes the complete procedure carried out in order to determine the cause of high levels of gases detected in chromatographic determinations performed in Current Transformers (CT) oil. These analyses of gases are normally included in routine maintenance work. The obtained results could evidence some possible damage in the machine insulation. According to the electrical stresses that Current Transformers are typically subjected to, it was presumed that the cause of the possible damaged could be the high-frequency transients that take place during air disconnect switch operations. Therefore, with the aim of determining the presence of such electrical stress, field measurements were performed. A specially designed measuring system was utilized to accomplish this goal. Taking into account the difficulties normally encountered when measuring currents flowing through Current Transformers to ground, especially in terms of accuracy, it was decided to perform voltage measurements. Then, by determining the real frequency response of the CT in the range of interest, it was possible to achieve such currents by computer simulations. In order to achieve accurate results in the simulations, it was necessary to develop an appropriate electrical model of this type of transformers in the analyzed frequency range. Once the model was carefully adjusted, computer simulations were performed. As a result, both shape and magnitude of such currents were also achieved. Finally, one of the Current Transformers with high levels of gases was taken out of service. Then, it was completely disassembled so as to confirm the suspected damage in the insulation. The results yielded in the inspection of the insulation are commented at the end of this work.Instituto de Investigaciones Tecnológicas para Redes y Equipos Eléctricos (IITREE

Pneumatocele formation following COVID-19 pneumonia

A 61-year-old man with no significant medical history presented to the emergency department with worsening dyspnea a week after close con-tact with someonewhohad COVID-19. Hewas unvaccinated. He washypoxemic, and the chest radiograph showed bilateralopacities consistent withCOVID-19 pneumonia and tested positive for RNA from SARS-CoV-2. Blood tests showed raised inflammatory markers. Computed tomography (CT)of the chest demonstrated bilateralground-glass opacities. Thepatient washospitalized andtreated with high-flow nasaloxygentherapy, dexameth-asone, and sarilumab. His clinical status improved, and hewas discharged home after 1 week of hospitalization.Three weekslater, hepresented againwith worsening dyspnea, fever, and pleuritic chest pain. A CT pulmonary angiography ruled out pulmonary embolism (Fig. 1A, B) but demonstrated athin-walled cystic lesion with an air–fluid level (Fig. 1A, arrowheads) that suggested an infected pneumatocele. The patient was managed conserva-tively with amoxicillin/clavulanic acid for 3 weeks. During the follow-up, the patient reported the disappearance of symptomatology

Simultaneous multi-frequency observation of the unknown redshift blazar PG1553+113 in March-April 2008

5 páginas, 2 figuras, 3 tablas.-- El Pdf del artículo es la versión pre-print: arXiv: arXiv:0911.1088.-- MAGIC Collaboration: et al.The blazar PG 1553+113 is a well known TeV γ-ray emitter. In this paper we determine its spectral energy distribution through simultaneous multi-frequency data to study its emission processes. An extensive campaign was carried out between March and April 2008, where optical, X-ray, high-energy (HE) γ-ray, and very-high-energy (VHE) γ-ray data were obtained with the KVA, Abastumani, REM, RossiXTE/ASM, AGILE and MAGIC telescopes, respectively. We combine the data to derive the source's spectral energy distribution and interpret its double-peaked shape within the framework of a synchrotron self-Compton model.Major support from Germany’s Bundesministerium f¨ur Bildung, Wissenschaft, Forschung und Technologie and Max-Planck-Gesellschaft, Italy’s Istituto Nazionale di Fisica Nucleare (INFN) and Istituto Nazionale di Astrofisica (INAF), and Spain’s Ministerio de Ciencia e Innovacion is gratefully acknowledged. The work was also supported by Switzerland’s ETH Research grant TH34/043, Poland’s Ministertwo Nauki i Szkolnictwa Wy˙zszego grant N N203 390834, and Germany’s Young Investigator Program of the Helmholtz Gemeinschaft. This work was also supported by Georgian National Science Foundation grant GNSF/ST07/4-180. EP acknowledges support from the Italian Space Agency through grants ASI-INAF I/023/05/0 and ASI I/088/06/0.Peer reviewe

MAGIC observation of the GRB 080430 afterglow

6 páginas, 1 figura.-- El Pdf del artículo es la versión pre-print: arXiv:1004.3665v2.-- MAGIC Collaboration: et al.[Context]: Gamma-ray bursts are cosmological sources emitting radiation from the gamma-rays to the radio band. Substantial observational efforts have been devoted to the study of gamma-ray bursts during the prompt phase, i.e. the initial burst of high-energy radiation, and during the long-lasting afterglows. In spite of many successes in interpreting these phenomena, there are still several open key questions about the fundamental emission processes, their energetics and the environment. [Aims]: Independently of specific gamma-ray burst theoretical recipes, spectra in the GeV/TeV range are predicted to be remarkably simple, being satisfactorily modeled with power-laws, and therefore offer a very valuable tool to probe the extragalactic background light distribution. Furthermore, the simple detection of a component at very-high energies, i.e. at ~100 GeV, would solve the ambiguity about the importance of various possible emission processes, which provide barely distinguishable scenarios at lower energies. [Methods]: We used the results of the MAGIC telescope observation of the moderate resdhift (z ~ 0.76) GRB 080430 at energies above about 80 GeV, to evaluate the perspective for late-afterglow observations with ground based GeV/TeV telescopes. [Results]: We obtained an upper limit of F95% CL = 5.5 × 10-11 erg cm-2 s-1 for the very-high energy emission of GRB 080430, which cannot set further constraints on the theoretical scenarios proposed for this object also due to the difficulties in modeling the low-energy afterglow. Nonetheless, our observations show that Cherenkov telescopes have already reached the required sensitivity to detect the GeV/TeV emission of GRBs at moderate redshift (z ≲ 0.8), provided the observations are carried out at early times, close to the onset of their afterglow phase.The support of the German BMBF and MPG, the Italian INFN and Spanish MICINN is gratefully acknowledged. This work was also supported by ETH Research Grant TH 34/043, by the Polish MNiSzW Grant N N203 390834, and by the YIP of the Helmholtz Gemeinschaft.Peer reviewe

Glucose Levels as a Mediator of the Detrimental E ect of Abdominal Obesity on Relative Handgrip Strength in Older Adults

Excess central adiposity accelerates the decline of muscle strength in older people. Additionally, hyperglycemia, independent of associated comorbidities, is related to the loss of muscle mass and strength, and contributes to functional impairment in older adults. We studied the mediation e ect of glucose levels, in the relationship between abdominal obesity and relative handgrip strength (HGS). A total of 1571 participants (60.0% women, mean age 69.1 7.0 years) from 86 municipalities were selected following a multistage area probability sampling design. Measurements included demographic and anthropometric/adiposity markers (weight, height, body mass index, and waist circumference). HGS was measured using a digital dynamometer for three sets and the mean value was recorded. The values were normalized to body weight (relative HGS). Fasting glucose was analyzed by enzymatic colorimetric methods. Mediation analyses were performed to identify associations between the independent variable (abdominal obesity) and outcomes (relative HGS), as well as to determine whether fasting glucose levels mediated the relationship between excess adiposity and relative HGS. A total of 1239 (78.8%) had abdominal obesity. Abdominal obesity had a negative e ect on fasting glucose ( ß = 9.04, 95% CI = 5.87 to 12.21); while fasting glucose to relative HGS was inversely related ( ß = -0.003, 95% CI = -0.005 to -0.001), p < 0.001. The direct e ect of abdominal obesity on relative HGS was statistically significant ( ß = -0.069, 95% CI = -0.082 to -0.057), p < 0.001. Lastly, fasting glucose levels mediates the detrimental e ect of abdominal obesity on relative HGS (indirect effect = -0.002, 95% CI = -0.004 to -0.001), p < 0.001. Our results suggest that the glucose level could worsen the association between abdominal obesity status and lower HGS. Thus, it is plausible to consider fasting glucose levels when assessing older adults with excess adiposity and/or suspected loss of muscle mass