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2.
Nature ; 562(7725): 82-85, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30283106

RESUMO

SS 433 is a binary system containing a supergiant star that is overflowing its Roche lobe with matter accreting onto a compact object (either a black hole or neutron star)1-3. Two jets of ionized matter with a bulk velocity of approximately 0.26c (where c is the speed of light in vacuum) extend from the binary, perpendicular to the line of sight, and terminate inside W50, a supernova remnant that is being distorted by the jets2,4-8. SS 433 differs from other microquasars (small-scale versions of quasars that are present within our own Galaxy) in that the accretion is believed to be super-Eddington9-11, and the luminosity of the system is about 1040 ergs per second2,9,12,13. The lobes of W50 in which the jets terminate, about 40 parsecs from the central source, are expected to accelerate charged particles, and indeed radio and X-ray emission consistent with electron synchrotron emission in a magnetic field have been observed14-16. At higher energies (greater than 100 gigaelectronvolts), the particle fluxes of γ-rays from X-ray hotspots around SS 433 have been reported as flux upper limits6,17-20. In this energy regime, it has been unclear whether the emission is dominated by electrons that are interacting with photons from the cosmic microwave background through inverse-Compton scattering or by protons that are interacting with the ambient gas. Here we report teraelectronvolt γ-ray observations of the SS 433/W50 system that spatially resolve the lobes. The teraelectronvolt emission is localized to structures in the lobes, far from the centre of the system where the jets are formed. We have measured photon energies of at least 25 teraelectronvolts, and these are certainly not Doppler-boosted, because of the viewing geometry. We conclude that the emission-from radio to teraelectronvolt energies-is consistent with a single population of electrons with energies extending to at least hundreds of teraelectronvolts in a magnetic field of about 16 microgauss.

3.
Neurol Sci ; 45(7): 3183-3189, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38300400

RESUMO

BACKGROUND: Comorbidity between myasthenia gravis (MG) and other autoimmune diseases is well-documented. However, concurrent MG and Parkinson's disease (PD) have rarely been described. This concurrence has mostly been considered coincidental in cases reported to date. MATERIAL/METHODS: We characterized patients with concurrent MG and PD within a cohort of 631 MG patients by gender, age, MGFA class, quantitative MG score at diagnosis, UPDRS score at diagnosis, and the DaTSCAN uptake pattern, to determine the frequency and the phenotype of individuals with these two concurrent entities. Meta-analysis of cases in the literature was used for comparison with our series. RESULTS: Eighteen cases were identified in which the two diseases were concurrent. The major characteristics of the phenotype are male prevalence, late-onset MG, and frequent initial symptoms of dropped head and oculobulbar involvement. DAT confirmed reduced bilateral uptake in eleven patients and reduced unilateral uptake in the others. CONCLUSIONS: To our knowledge, this is the largest reported series of concurrent MG and PD. This concurrence is more common than expected (2.85%). Either MG or PD may appear first. We found no iatrogenic relationship for the order of appearance. The overlapping of symptoms sometimes leads physicians to overlook the second disease, instead viewing it as a deterioration of the first. This study describes patients with well-documented diagnoses of both MG and PD, thus providing further indications of a shared etiology of these two diseases. Prospective studies including genetic, immunological, and environmental analysis are necessary to identify possible common pathogenic mechanisms.


Assuntos
Miastenia Gravis , Doença de Parkinson , Humanos , Miastenia Gravis/epidemiologia , Miastenia Gravis/complicações , Doença de Parkinson/epidemiologia , Doença de Parkinson/complicações , Masculino , Feminino , Idoso , Pessoa de Meia-Idade , Espanha/epidemiologia , Estudos de Coortes , Idoso de 80 Anos ou mais , Comorbidade , Adulto
4.
Public Health ; 225: 63-65, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37922587

RESUMO

OBJECTIVE: We investigated a possible pandemic fatigue effect, comparing adherence to compulsory mask use outdoors in Barcelona during the fourth and sixth waves of the pandemic. STUDY DESIGN: We used naturalistic observation to determine the degree of pedestrians' compliance. METHODS: We assessed mask use outdoors in a sample of pedestrians in Barcelona between 28 December 2021 and 9 February 2022 (during the sixth wave in Spain), and compared it with the fourth wave (which was between 5 April 2021 and 29 April 2021). Masks were compulsory in both periods. RESULTS: The population studied amounted to 45,116 people (21,246 in the fourth wave and 23,870 in the sixth wave). In the sixth wave, only 67.3% wore a mask correctly, 18.6% did so incorrectly and 14.1% did not wear a mask, while the figures for the fourth wave were 78.2%, 16.3% and 5.5%, respectively (P = 0.001). CONCLUSION: Our results suggest that adherence was high in the population studied, but with an evident fatigue effect when the two waves were compared, as the proportion of individuals wearing a mask correctly declined compared to the fourth wave. These results suggest that policymakers need guidance on adopting clear and enforceable guidelines during future mask mandates, assessing advantages and drawbacks in terms of the population's behavior to prevent the fatigue effect.


Assuntos
Fadiga , Pedestres , Humanos , Espanha/epidemiologia , Fadiga/epidemiologia , Fadiga/prevenção & controle , Pandemias , Máscaras
5.
Phys Rev Lett ; 124(13): 131101, 2020 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-32302173

RESUMO

Because of the high energies and long distances to the sources, astrophysical observations provide a unique opportunity to test possible signatures of Lorentz invariance violation (LIV). Superluminal LIV enables the decay of photons at high energy. The high altitude water Cherenkov (HAWC) observatory is among the most sensitive gamma-ray instruments currently operating above 10 TeV. HAWC finds evidence of 100 TeV photon emission from at least four astrophysical sources. These observations exclude, for the strongest of the limits set, the LIV energy scale to 2.2×10^{31} eV, over 1800 times the Planck energy and an improvement of 1 to 2 orders of magnitude over previous limits.

6.
Phys Rev Lett ; 124(2): 021102, 2020 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-32004015

RESUMO

We present the first catalog of gamma-ray sources emitting above 56 and 100 TeV with data from the High Altitude Water Cherenkov Observatory, a wide field-of-view observatory capable of detecting gamma rays up to a few hundred TeV. Nine sources are observed above 56 TeV, all of which are likely galactic in origin. Three sources continue emitting past 100 TeV, making this the highest-energy gamma-ray source catalog to date. We report the integral flux of each of these objects. We also report spectra for three highest-energy sources and discuss the possibility that they are PeVatrons.

7.
Clin Genet ; 93(3): 450-458, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-28671287

RESUMO

Protein misfolding has been linked to numerous inherited diseases. Loss- and gain-of-function mutations (common features of genetic diseases) may cause the destabilization of proteins, leading to alterations in their properties and/or cellular location, resulting in their incorrect functioning. Misfolded proteins can, however, be rescued via the use of proteostasis regulators and/or pharmacological chaperones, suggesting that treatments with small molecules might be developed for a range of genetic diseases. This work describes the potential of these small molecules in this respect, including for the treatment of congenital disorder of glycosylation (CDG) due to phosphomannomutase 2 deficiency (PMM2-CDG).


Assuntos
Deficiências na Proteostase/tratamento farmacológico , Deficiências na Proteostase/etiologia , Animais , Ensaios Clínicos como Assunto , Descoberta de Drogas , Predisposição Genética para Doença , Glicosilação/efeitos dos fármacos , Humanos , Mitocôndrias , Mutação , Deficiências na Proteostase/diagnóstico , Deficiências na Proteostase/metabolismo
8.
Clin Exp Allergy ; 47(1): 129-138, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27859832

RESUMO

Inconsistent results have been reported regarding IL-5 blockade treatment in asthma. There were no direct between-treatment comparisons. Only differences between each drug and placebo were studied. We identified all RCTs with anti-IL5 treatments for patients with asthma over the 1990-September 2015 period. RCTs were searched on Medline, Cochrane and Embase. At least 50 patients were enrolled in each study. Outcomes considered were exacerbation rate reduction, FEV1 changes, ACQ-5 improvement, adverse events and serious adverse events. A global meta-analysis was first conducted followed by an indirect comparison of each IL-5-targeting drug: benralizumab, reslizumab and mepolizumab. Further eosinophilic subgroup analysis and sensitivity analysis were also conducted in case of heterogeneity. Ten trials involving 3421 patients were eligible for meta-analysis. IL-5 blockade significantly reduced annual exacerbation rates vs. placebo by 40% [29-50] (P < 0.01, I2 = 0.61). ACQ-5 was significantly improved vs. placebo but below the recognized MCID level (-0.31 [-0.41, -0.21], P < 0.01, I2 = 0.11). FEV1 changes from baseline were improved vs. placebo by 0.09 L [0.05-0.12] (P < 0.01, I2 = 0.28). The subgroup analysis identified a slight additional improvement in mean treatment effects in eosinophilic (> 300 mm3 /L) patients with severe asthma. Similar patterns and rates of adverse events and severe adverse events were reported with the three drugs. The data interpretations were not affected by the sensitivity analysis. IL-5 blockade appears to be a relevant treatment strategy to improve severe asthma management, particularly for eosinophilic patients. No clear superiority appeared between the drugs when appropriate doses were compared.


Assuntos
Antiasmáticos/uso terapêutico , Anticorpos Monoclonais/uso terapêutico , Asma/tratamento farmacológico , Interleucina-5/antagonistas & inibidores , Antiasmáticos/administração & dosagem , Antiasmáticos/efeitos adversos , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais/efeitos adversos , Asma/diagnóstico , Asma/imunologia , Asma/metabolismo , Biomarcadores , Progressão da Doença , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Testes de Função Respiratória , Índice de Gravidade de Doença , Resultado do Tratamento
9.
Learn Behav ; 45(3): 211-227, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28039580

RESUMO

Four experiments in human instrumental learning explored the associations involving the context that develop after three trials of training on simple discriminations. Experiments 1 and 4 found a deleterious effect of switching the learning context that cannot be explained by the context-outcome binary associations commonly used to explain context-switch effects after short training in human predictive learning and in animal Pavlovian conditioning. Evidence for context-outcome (Experiment 2), context-discriminative stimulus (Experiment 3), and context-instrumental response (Experiment 4) binary associations was found within the same training paradigm, suggesting that contexts became associated with all the elements of the situation, regardless of whether those associations played a role in a specific context-switch effect detected on performance.


Assuntos
Aprendizagem por Associação , Condicionamento Operante , Aprendizagem por Discriminação , Meio Ambiente , Adolescente , Adulto , Feminino , Humanos , Masculino , Adulto Jovem
10.
Clin Genet ; 87(1): 42-8, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-24720419

RESUMO

Deficiencies in glycosyltransferases, glycosidases or nucleotide-sugar transporters involved in protein glycosylation lead to congenital disorders of glycosylation (CDG), a group of genetic diseases mostly showing multisystem phenotype. Despite recent advances in the biochemical and molecular knowledge of these diseases, no effective therapy exists for most. Efforts are now being directed toward therapies based on identifying new targets, which would allow to treat specific patients in a personalized way. This work presents proof-of concept for the antisense RNA rescue of the Golgi-resident protein TMEM165, a gene involved in a new type of CDG with a characteristic skeletal phenotype. Using a functional in vitro splicing assay based on minigenes, it was found that the deep intronic change c.792+182G>A is responsible for the insertion of an aberrant exon, corresponding to an intronic sequence. Antisense morpholino oligonucleotide therapy targeted toward TMEM165 mRNA recovered normal protein levels in the Golgi apparatus of patient-derived fibroblasts. This work expands the application of antisense oligonucleotide-mediated pseudoexon skipping to the treatment of a Golgi-resident protein, and opens up a promising treatment option for this specific TMEM165-CDG.


Assuntos
Defeitos Congênitos da Glicosilação/enzimologia , Defeitos Congênitos da Glicosilação/terapia , Éxons/genética , Terapia Genética/métodos , Proteínas de Membrana/genética , Mutagênese Insercional/genética , RNA Antissenso/genética , Análise de Variância , Antiporters , Proteínas de Transporte de Cátions , Primers do DNA/genética , DNA Complementar/genética , Fibroblastos , Complexo de Golgi/genética , Humanos , Immunoblotting , Técnicas In Vitro/métodos , Microscopia de Fluorescência , Oligorribonucleotídeos Antissenso/genética , Oligorribonucleotídeos Antissenso/uso terapêutico
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