55 research outputs found
Unusual magneto-transport of YBa2Cu3O7-d films due to the interplay of anisotropy, random disorder and nanoscale periodic pinning
We study the general problem of a manifold of interacting elastic lines whose
spatial correlations are strongly affected by the competition between random
and ordered pinning. This is done through magneto-transport experiments with
YBa2Cu3O7-d thin films that contain a periodic vortex pinning array created via
masked ion irradiation, in addition to the native random pinning. The strong
field-matching effects we observe suggest the prevalence of periodic pinning,
and indicate that at the matching field each vortex line is bound to an
artificial pinning site. However, the vortex-glass transition dimensionality,
quasi-2D instead of the usual 3D, evidences reduced vortex-glass correlations
along the vortex line. This is also supported by an unusual angular dependence
of the magneto-resistance, which greatly differs from that of Bose-glass
systems. A quantitative analysis of the angular magnetoresistance allows us to
link this behaviour to the enhancement of the system anisotropy, a collateral
effect of the ion irradiation
A high-temperature superconducting weak-link defined by ferroelectric field-effect
In all-oxide ferroelectric (FE) - superconductor (S) bilayers, due to the low
carrier concentration of oxides compared to transition metals, the FE
interfacial polarization charges induce an accumulation (or depletion) of
charge carriers in the S. This leads either to an enhancement or a depression
of its critical temperature depending on FE polarization direction.Here we
exploit this effect at a local scale to define planar weak-links in
high-temperature superconducting wires. This is realized in
BiFeO3(FE)/YBa2Cu3O7(S)bilayers in which the remnant FE domain structure is
written at will by locally applying voltage pulses with a conductive-tip atomic
force microscope. In this fashion, the FE domain pattern defines a spatial
modulation of superconductivity. This allows us to write a device whose
electrical transport shows different temperature regimes and magnetic field
matching effects that are characteristic of Josephson coupled weak-links. This
illustrates the potential of the ferroelectric approach for the realization of
high-temperature superconducting devices
Long-range propagation and interference of d-wave superconducting pairs in graphene
Resumen del trabajo presentado a la Conference Low dimensional superconducting hybrids for novel quantum functionalities, celebrada en Paris (Francia) del 12 al 14 de octubre de 2021.Peer reviewe
Severe manifestations of SARS-CoV-2 in children and adolescents: from COVID-19 pneumonia to multisystem inflammatory syndrome: a multicentre study in pediatric intensive care units in Spain
Background
Multisystem inflammatory syndrome temporally associated with COVID-19 (MIS-C) has been described as a novel and often severe presentation of SARS-CoV-2 infection in children. We aimed to describe the characteristics of children admitted to Pediatric Intensive Care Units (PICUs) presenting with MIS-C in comparison with those admitted with SARS-CoV-2 infection with other features such as COVID-19 pneumonia.
Methods
A multicentric prospective national registry including 47 PICUs was carried out. Data from children admitted with confirmed SARS-CoV-2 infection or fulfilling MIS-C criteria (with or without SARS-CoV-2 PCR confirmation) were collected. Clinical, laboratory and therapeutic features between MIS-C and non-MIS-C patients were compared.
Results
Seventy-four children were recruited. Sixty-one percent met MIS-C definition. MIS-C patients were older than non-MIS-C patients (pâ=â0.002): 9.4 years (IQR 5.5â11.8) vs 3.4 years (IQR 0.4â9.4). A higher proportion of them had no previous medical history of interest (88.2% vs 51.7%, pâ=â0.005). Non-MIS-C patients presented more frequently with respiratory distress (60.7% vs 13.3%, pâ<â0.001). MIS-C patients showed higher prevalence of fever (95.6% vs 64.3%, pâ<â0.001), diarrhea (66.7% vs 11.5%, pâ<â0.001), vomits (71.1% vs 23.1%, pâ=â0.001), fatigue (65.9% vs 36%, pâ=â0.016), shock (84.4% vs 13.8%, pâ<â0.001) and cardiac dysfunction (53.3% vs 10.3%, pâ=â0.001). MIS-C group had a lower lymphocyte count (pâ<â0.001) and LDH (pâ=â0.001) but higher neutrophil count (pâ=â0.045), neutrophil/lymphocyte ratio (pâ<â0.001), C-reactive protein (pâ<â0.001) and procalcitonin (pâ<â0.001). Patients in the MIS-C group were less likely to receive invasive ventilation (13.3% vs 41.4%, pâ=â0.005) but were more often treated with vasoactive drugs (66.7% vs 24.1%, pâ<â0.001), corticosteroids (80% vs 44.8%, pâ=â0.003) and immunoglobulins (51.1% vs 6.9%, pâ<â0.001). Most patients were discharged from PICU by the end of data collection with a median length of stay of 5 days (IQR 2.5â8 days) in the MIS-C group. Three patients died, none of them belonged to the MIS-C group.
Conclusions
MIS-C seems to be the most frequent presentation among critically ill children with SARS-CoV-2 infection. MIS-C patients are older and usually healthy. They show a higher prevalence of gastrointestinal symptoms and shock and are more likely to receive vasoactive drugs and immunomodulators and less likely to need mechanical ventilation than non-MIS-C patients
The type 2C phosphatase Wip1: An oncogenic regulator of tumor suppressor and DNA damage response pathways
The Wild-type p53-induced phosphatase 1, Wip1 (or PPM1D), is unusual in that it is a serine/threonine phosphatase with oncogenic activity. A member of the type 2C phosphatases (PP2CÎŽ), Wip1 has been shown to be amplified and overexpressed in multiple human cancer types, including breast and ovarian carcinomas. In rodent primary fibroblast transformation assays, Wip1 cooperates with known oncogenes to induce transformed foci. The recent identification of target proteins that are dephosphorylated by Wip1 has provided mechanistic insights into its oncogenic functions. Wip1 acts as a homeostatic regulator of the DNA damage response by dephosphorylating proteins that are substrates of both ATM and ATR, important DNA damage sensor kinases. Wip1 also suppresses the activity of multiple tumor suppressors, including p53, ATM, p16INK4a and ARF. We present evidence that the suppression of p53, p38 MAP kinase, and ATM/ATR signaling pathways by Wip1 are important components of its oncogenicity when it is amplified and overexpressed in human cancers
Incidence, clinical characteristics and management of inflammatory bowel disease in Spain: large-scale epidemiological study
(1) Aims: To assess the incidence of inflammatory bowel disease (IBD) in Spain, to describe the main epidemiological and clinical characteristics at diagnosis and the evolution of the disease, and to explore the use of drug treatments. (2) Methods: Prospective, population-based nationwide registry. Adult patients diagnosed with IBDâCrohnâs disease (CD), ulcerative colitis (UC) or IBD unclassified (IBD-U)âduring 2017 in Spain were included and were followed-up for 1 year. (3) Results: We identified 3611 incident cases of IBD diagnosed during 2017 in 108 hospitals covering over 22 million inhabitants. The overall incidence (cases/100, 000 person-years) was 16 for IBD, 7.5 for CD, 8 for UC, and 0.5 for IBD-U; 53% of patients were male and median age was 43 years (interquartile range = 31â56 years). During a median 12-month follow-up, 34% of patients were treated with systemic steroids, 25% with immunomodulators, 15% with biologics and 5.6% underwent surgery. The percentage of patients under these treatments was significantly higher in CD than UC and IBD-U. Use of systemic steroids and biologics was significantly higher in hospitals with high resources. In total, 28% of patients were hospitalized (35% CD and 22% UC patients, p < 0.01). (4) Conclusion: The incidence of IBD in Spain is rather high and similar to that reported in Northern Europe. IBD patients require substantial therapeutic resources, which are greater in CD and in hospitals with high resources, and much higher than previously reported. One third of patients are hospitalized in the first year after diagnosis and a relevant proportion undergo surgery. © 2021 by the authors. Licensee MDPI, Basel, Switzerland
Spread of a SARS-CoV-2 variant through Europe in the summer of 2020.
Following its emergence in late 2019, the spread of SARS-CoV-21,2 has been tracked by phylogenetic analysis of viral genome sequences in unprecedented detail3â5. Although the virus spread globally in early 2020 before borders closed, intercontinental travel has since been greatly reduced. However, travel within Europe resumed in the summer of 2020. Here we report on a SARS-CoV-2 variant, 20E (EU1), that was identified in Spain in early summer 2020 and subsequently spread across Europe. We find no evidence that this variant has increased transmissibility, but instead demonstrate how rising incidence in Spain, resumption of travel, and lack of effective screening and containment may explain the variantâs success. Despite travel restrictions, we estimate that 20E (EU1) was introduced hundreds of times to European countries by summertime travellers, which is likely to have undermined local efforts to minimize infection with SARS-CoV-2. Our results illustrate how a variant can rapidly become dominant even in the absence of a substantial transmission advantage in favourable epidemiological settings. Genomic surveillance is critical for understanding how travel can affect transmission of SARS-CoV-2, and thus for informing future containment strategies as travel resumes. © 2021, The Author(s), under exclusive licence to Springer Nature Limited
Higher COVID-19 pneumonia risk associated with anti-IFN-α than with anti-IFN-Ï auto-Abs in children
We found that 19 (10.4%) of 183 unvaccinated children hospitalized for COVID-19 pneumonia had autoantibodies (auto-Abs) neutralizing type I IFNs (IFN-alpha 2 in 10 patients: IFN-alpha 2 only in three, IFN-alpha 2 plus IFN-omega in five, and IFN-alpha 2, IFN-omega plus IFN-beta in two; IFN-omega only in nine patients). Seven children (3.8%) had Abs neutralizing at least 10 ng/ml of one IFN, whereas the other 12 (6.6%) had Abs neutralizing only 100 pg/ml. The auto-Abs neutralized both unglycosylated and glycosylated IFNs. We also detected auto-Abs neutralizing 100 pg/ml IFN-alpha 2 in 4 of 2,267 uninfected children (0.2%) and auto-Abs neutralizing IFN-omega in 45 children (2%). The odds ratios (ORs) for life-threatening COVID-19 pneumonia were, therefore, higher for auto-Abs neutralizing IFN-alpha 2 only (OR [95% CI] = 67.6 [5.7-9,196.6]) than for auto-Abs neutralizing IFN-. only (OR [95% CI] = 2.6 [1.2-5.3]). ORs were also higher for auto-Abs neutralizing high concentrations (OR [95% CI] = 12.9 [4.6-35.9]) than for those neutralizing low concentrations (OR [95% CI] = 5.5 [3.1-9.6]) of IFN-omega and/or IFN-alpha 2
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