Nonthermal processes and neutrino emission from the black hole GRO J0422+32 in a bursting state

Context. GRO J0422+32 is a member of the class of low-mass X-ray binaries (LMXBs). It was discovered during an outburst in 1992. During the entire episode a persistent power-law spectral component extending up to ∼1 MeV was observed, which suggests that nonthermal processes should have occurred in the system. Aims. We study relativistic particle interactions and the neutrino production in the corona of GRO J0422+32, and explain the behavior of GRO J0422+32 during its recorded flaring phase. Methods. We have developed a magnetized corona model to fit the spectrum of GRO J0422+32 during the low-hard state. We also estimate neutrino emission and study the detectability of neutrinos with 1 km 3 detectors, such as IceCube. Results. The short duration of the flares (∼hours) and an energy cutoff around a few TeV in the neutrino spectrum make neutrino detection difficult. There are, however, many factors that can enhance neutrino emission. Conclusions. The northern-sky coverage and full duty cycle of IceCube make it possible to detect neutrino bursts from objects of this kind through time-dependent analysis.Facultad de Ciencias Astronómicas y Geofísica

Nonthermal processes and neutrino emission from the black hole GRO J0422+32 in a bursting state

Context. GRO J0422+32 is a member of the class of low-mass X-ray binaries (LMXBs). It was discovered during an outburst in 1992. During the entire episode a persistent power-law spectral component extending up to ∼1 MeV was observed, which suggests that nonthermal processes should have occurred in the system. Aims. We study relativistic particle interactions and the neutrino production in the corona of GRO J0422+32, and explain the behavior of GRO J0422+32 during its recorded flaring phase. Methods. We have developed a magnetized corona model to fit the spectrum of GRO J0422+32 during the low-hard state. We also estimate neutrino emission and study the detectability of neutrinos with 1 km 3 detectors, such as IceCube. Results. The short duration of the flares (∼hours) and an energy cutoff around a few TeV in the neutrino spectrum make neutrino detection difficult. There are, however, many factors that can enhance neutrino emission. Conclusions. The northern-sky coverage and full duty cycle of IceCube make it possible to detect neutrino bursts from objects of this kind through time-dependent analysis.Facultad de Ciencias Astronómicas y Geofísica

Bibliometric analysis in paediatric dental journals listed in journal citation reports. Current trends

Aim The aim of this study was to analyse articles published in paediatric dental journals included in Journal Citation Reports (JCR), to determine current trends in paediatric publishing. Methods Articles included in paediatric dentistry journals in 2020 JCR were selected, published during the period 2008– 2020. After applying inclusion criteria, author-based parameters (article title, first author’s name, institution, sex and number of authors, number of affiliations, first/last author’s origin and geographic origin), and article-based parameters (article type, main topic, research design) were registered for each article. Results A total of 3,027 articles were analysed. The percentage of female authors showed an increasing positive tendency over the decade and the top producing country was the USA (16.5%). Dental surgery was the most recurrent topic (23.4%). Regarding the origin of the first author’s affiliation, 51% proceeded from the paediatric dentistry departments belonging to public institutions, with a decreasing trend in non-academic/ private affiliations. Positive and negative correlations exist between citation count and other variables. Conclusions International Journal of Paediatric Dentistry, Journal of Clinical Pediatric Dentistry, European Journal of Paediatric Dentistry and Pediatric Dentistry were the four main journals in terms of production volume, USA being the most productive country. The most recurrent topic was dental surgery, and the most common design was observational studies. Study design, geographic origin of the articles, article type and main subject of the article might predict citation.Odontologí

Characteristics associated with the transition to partial breastfeeding prior to 6 months of age : Data from seven sites in a birth cohort study

ACKNOWLEDGMENTS The Etiology, Risk Factors and Interactions of Enteric Infections and Malnutrition and the Consequences for Child Health and Development Project (MAL-ED) was carried out as a collaborative project supported by the Bill & Melinda Gates Foundation, the Foundation for the NIH and the NIH/Fogarty International Center.Peer reviewedPublisher PD

Manejo de la cesación tabáquica entre residentes de cardiología de Iberoamérica

Si bien los cardiólogos asisten cotidianamente a pacientes que sufren daño por el tabaquismo, no se conoce el grado de formación que reciben sobre esta problemática durante su residencia. Debido a ello nos propusimos evaluar las preferencias y prácticas de los residentes de cardiología para la cesación tabáquica de los pacientes que asisten. Encuesta cerrada, prefijada, voluntaria y anónima entre médicos que realizaban la especialidad de cardiología en cinco países de Latinoamérica y España. Se encuestaron 716 residentes: un 62.4% de Argentina, un 19% de México, un 6.8% de España, un 6.7% de Chile, un 3.2% de Uruguay y un 1.9% de Paraguay. Con respecto a la importancia que asignaban a esta problemática (empleando una escala de 1-10), el 85.8% le asignó a esta pregunta una puntuación de 8 o mayor. Mientras el 80.5% de los participantes expresó dar consejo breve antitabáquico sistemáticamente, solamente un 27.7% empleaban terapia farmacológica con este fin. Entre quienes no empleaban terapia farmacológica, el 58.3% manifestó que el motivo era no encontrarse familiarizados con los tratamientos. El 62.9% de los encuestados dijo no haber recibido ningún tipo de formación en esta problemática. Aquellos residentes que recibieron algún tipo de formación manifestaron sentirse más preparados (p < 0.0001). Encontramos un bajo conocimiento sobre el tratamiento farmacológico y relativamente poca seguridad por parte de los residentes de cardiología para brindar asistencia en cesación tabáquica. Consideramos esencial incluir este tópico en la formación de los futuros cardiólogos a fin de lograr una prevención cardiovascular más integral

What Drives the Expansion of Giant HII Regions?: A Study of Stellar Feedback in 30 Doradus

Observations show that star formation is an inefficient and slow process. This result can be attributed to the injection of energy and momentum by stars that prevents free-fall collapse of molecular clouds. The mechanism of this stellar feedback is debated theoretically: possible sources of pressure include the classical warm HII gas, the hot gas generated by shock-heating from stellar winds and supernovae, direct radiation of stars, and the dust-processed radiation field trapped inside the HII shell. In this paper, we measure observationally the pressures associated with each component listed above across the giant HII region 30 Doradus in the Large Magellanic Cloud. We exploit high-resolution, multi-wavelengh images (radio, infrared, optical, and X-ray) to map these pressures as a function of position. We find that radiation pressure dominates within 75 pc of the central star cluster, R136, while the HII gas pressure dominates at larger radii. By contrast, the dust-processed radiation pressure and hot gas pressure are generally weak and not dynamically important, although the hot gas pressure may have played a more significant role at early times. Based on the low X-ray gas pressures, we demonstrate that the hot gas is only partially confined and must be leaking out the HII shell. Additionally, we consider the implications of a dominant radiation pressure on the early dynamics of 30 Doradus.Comment: 14 pages, 17 figures; ApJ in pres

Leigh syndrome is the main clinical characteristic of PTCD3 deficiency

Mitochondrial translation defects are a continuously growing group of disorders showing a large variety of clinical symptoms including a wide range of neurological abnormalities. To date, mutations in PTCD3, encoding a component of the mitochondrial ribosome, have only been reported in a single individual with clinical evidence of Leigh syndrome. Here, we describe three additional PTCD3 individuals from two unrelated families, broadening the genetic and phenotypic spectrum of this disorder, and provide definitive evidence that PTCD3 deficiency is associated with Leigh syndrome. The patients presented in the first months of life with psychomotor delay, respiratory insufficiency and feeding difficulties. The neurologic phenotype included dystonia, optic atrophy, nystagmus and tonic-clonic seizures. Brain MRI showed optic nerve atrophy and thalamic changes, consistent with Leigh syndrome. WES and RNA-seq identified compound heterozygous variants in PTCD3 in both families: c.[1453-1G>C];[1918C>G] and c.[710del];[902C>T]. The functional consequences of the identified variants were determined by a comprehensive characterization of the mitochondrial function. PTCD3 protein levels were significantly reduced in patient fibroblasts and, consistent with a mitochondrial translation defect, a severe reduction in the steady state levels of complexes I and IV subunits was detected. Accordingly, the activity of these complexes was also low, and high-resolution respirometry showed a significant decrease in the mitochondrial respiratory capacity. Functional complementation studies demonstrated the pathogenic effect of the identified variants since the expression of wild-type PTCD3 in immortalized fibroblasts restored the steady-state levels of complexes I and IV subunits as well as the mitochondrial respiratory capacity. Additionally, minigene assays demonstrated that three of the identified variants were pathogenic by altering PTCD3 mRNA processing. The fourth variant was a frameshift leading to a truncated protein. In summary, we provide evidence of PTCD3 involvement in human disease confirming that PTCD3 deficiency is definitively associated with Leigh syndrome.© 2022 The Authors. Brain Pathology published by John Wiley & Sons Ltd on behalf of International Society of Neuropathology

Hemoparasites effect on interferon-gamma and miRNA 125b expression in Bubalus bubalis

This study aimed to determine and evaluate the effect of the g4467 G>A SNP on the expression profile of IFN-γ and miRNA 125b in dairy buffaloes (Bubalus bubalis) with and without hemoparasites. Molecular diagnosis was performed by Polymerase Chain Reaction (PCR) on 145 buffaloes for Babesia spp., Trypanosoma vivax, and Anaplasma marginale. All buffaloes were investigated for the presence or absence of the polymorphism and genotyped using the restriction enzyme. Real-time PCR (RT-qPCR) quantified the expression of IFN-γ and miRNA 125b. All buffaloes were negative for Babesia spp. and A. marginale, and only 12 were positive for T. vivax. The genotypes GG, GA, and AA were found in proportions of 3.4%, 2.1%, and 94.5%, respectively. The A allele was the most frequent (95.5%). The SNP showed deviation from Hardy-Weinberg equilibrium (HWE) (P<0.05) and a deficit of heterozygotes with FIS 0.759. All animals of the found genotypes expressed both genes, except for GG positive for T. vivax. IFN-γ expression was higher for GA and GG negative (P<0.05) and AA positive. However, miRNA 125b expression was lower for AA and GA positive and higher for AA, GA, and GG negative. AA-positive buffaloes for T. vivax may exhibit susceptibility due to higher IFN-γ expression and lower miRNA 125b. GG and GA-negative buffaloes exhibited higher expression in both, suggesting they have greater resistance to positive ones

Advancing in Schaaf-Yang syndrome pathophysiology: from bedside to subcellular analyses of truncated MAGEL2

Background Schaaf-Yang syndrome (SYS) is caused by truncating mutations in MAGEL2, mapping to the Prader-Willi region (15q11-q13), with an observed phenotype partially overlapping that of Prader-Willi syndrome. MAGEL2 plays a role in retrograde transport and protein recycling regulation. Our aim is to contribute to the characterisation of SYS pathophysiology at clinical, genetic and molecular levels. Methods We performed an extensive phenotypic and mutational revision of previously reported patients with SYS. We analysed the secretion levels of amyloid-β 1-40 peptide (Aβ1-40) and performed targeted metabolomic and transcriptomic profiles in fibroblasts of patients with SYS (n=7) compared with controls (n=11). We also transfected cell lines with vectors encoding wild- type (WT) or mutated MAGEL2 to assess stability and subcellular localisation of the truncated protein. Results Functional studies show significantly decreased levels of secreted Aβ1-40 and intracellular glutamine in SYS fibroblasts compared with WT. We also identified 132 differentially expressed genes, including non-coding RNAs (ncRNAs) such as HOTAIR, and many of them related to developmental processes and mitotic mechanisms. The truncated form of MAGEL2 displayed a stability similar to the WT but it was significantly switched to the nucleus, compared with a mainly cytoplasmic distribution of the WT MAGEL2. Based on the updated knowledge, we offer guidelines for the clinical management of patients with SYS. Conclusion A truncated MAGEL2 protein is stable and localises mainly in the nucleus, where it might exert a pathogenic neomorphic effect. Aβ1-40 secretion levels and HOTAIR mRNA levels might be promising biomarkers for SYS. Our findings may improve SYS understanding and clinical management

Elevated Plasma Endothelin-1 and Pulmonary Arterial Pressure in Children Exposed to Air Pollution

BackgroundControlled exposures of animals and humans to particulate matter (PM) or ozone air pollution cause an increase in plasma levels of endothelin-1, a potent vasoconstrictor that regulates pulmonary arterial pressure.ObjectivesThe primary objective of this field study was to determine whether Mexico City children, who are chronically exposed to levels of PM and O3 that exceed the United States air quality standards, have elevated plasma endothelin-1 levels and pulmonary arterial pressures.MethodsWe conducted a study of 81 children, 7.9 ± 1.3 years of age, lifelong residents of either northeast (n = 19) or southwest (n = 40) Mexico City or Polotitlán (n = 22), a control city with PM and O3 levels below the U.S. air quality standards. Clinical histories, physical examinations, and complete blood counts were done. Plasma endothelin-1 concentrations were determined by immunoassay, and pulmonary arterial pressures were measured by Doppler echocardiography.ResultsMexico City children had higher plasma endothelin-1 concentrations compared with controls (p < 0.001). Mean pulmonary arterial pressure was elevated in children from both northeast (p < 0.001) and southwest (p < 0.05) Mexico City compared with controls. Endothelin-1 levels in Mexico City children were positively correlated with daily outdoor hours (p = 0.012), and 7-day cumulative levels of PM air pollution < 2.5 μm in aerodynamic diameter (PM2.5) before endothelin-1 measurement (p = 0.03).ConclusionsChronic exposure of children to PM2.5 is associated with increased levels of circulating endothelin-1 and elevated mean pulmonary arterial pressure