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1.
Ann Med Surg (Lond) ; 86(8): 4921-4926, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39118732

RESUMEN

Introduction and importance: Schwannomas are benign tumors that arise from Schwann cells commonly located in peripheral nerves. Depending on the size and location of sciatic nerve Schwannoma clinical manifestations can either varies from symptoms simulating radiculopathies such as positive Lasegue sign on the affected side, gait weakness and paresthesia or just present with pain and an associated palpable mass. Case presentation: The authors present a case of a 34-year-old female patient suffering from pain, gait weakness, and a palpable mass since many months. The palpable mass was present in the posterior region of the left lower limb. Imaging studies reveal an extensive lesion measuring 35 cm×8 cm that extends from the gluteal region to the left popliteal fossa. Clinical discussion: The finding of a palpable mass during physical examination guided us towards the diagnostic suspicion and thus necessitating the direct imaging studies. When approaching such type of patients, a history of neurofibromatosis must be ruled out due to its frequent association. Surgical resection should focus on the preservation of neurovascular structures, which offers improvement of the symptoms and the quality of life of patients. Conclusion: Giant sciatic nerve schwannoma if excised completely can lead to relieve of symptoms. Although recurrences are uncommon follow-up for years is necessary.

2.
Nature ; 627(8002): 130-136, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38355793

RESUMEN

Genomic instability arising from defective responses to DNA damage1 or mitotic chromosomal imbalances2 can lead to the sequestration of DNA in aberrant extranuclear structures called micronuclei (MN). Although MN are a hallmark of ageing and diseases associated with genomic instability, the catalogue of genetic players that regulate the generation of MN remains to be determined. Here we analyse 997 mouse mutant lines, revealing 145 genes whose loss significantly increases (n = 71) or decreases (n = 74) MN formation, including many genes whose orthologues are linked to human disease. We found that mice null for Dscc1, which showed the most significant increase in MN, also displayed a range of phenotypes characteristic of patients with cohesinopathy disorders. After validating the DSCC1-associated MN instability phenotype in human cells, we used genome-wide CRISPR-Cas9 screening to define synthetic lethal and synthetic rescue interactors. We found that the loss of SIRT1 can rescue phenotypes associated with DSCC1 loss in a manner paralleling restoration of protein acetylation of SMC3. Our study reveals factors involved in maintaining genomic stability and shows how this information can be used to identify mechanisms that are relevant to human disease biology1.


Asunto(s)
Inestabilidad Genómica , Micronúcleos con Defecto Cromosómico , Animales , Humanos , Ratones , Cromosomas/genética , Daño del ADN , Inestabilidad Genómica/genética , Fenotipo , Sirtuina 1 , Mutaciones Letales Sintéticas
3.
Rev. panam. salud pública ; 48: e11, 2024. tab, graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1551020

RESUMEN

ABSTRACT Objective. To provide a comprehensive overview of geographical patterns (2001-2010) and time trends (1993-2012) of cancer incidence in children aged 0-19 years in Latin America and the Caribbean (LAC) and interpret the findings in the context of global patterns. Methods. Geographical variations in 2001-2010 and incidence trends over 1993-2012 in the population of LAC younger than 20 years were described using the database of the third volume of the International Incidence of Childhood Cancer study containing comparable data. Age-specific incidence per million person-years (ASR) was calculated for population subgroups and age-standardized (WSR) using the world standard population. Results. Overall, 36 744 unique cases were included in this study. In 2001-2010 the overall WSR in age 0-14 years was 132.6. The most frequent were leukemia (WSR 48.7), central nervous system neoplasms (WSR 23.0), and lymphoma (WSR 16.6). The overall ASR in age group 15-19 years was 152.3 with lymphoma ranking first (ASR 30.2). Incidence was higher in males than in females, and higher in South America than in Central America and the Caribbean. Compared with global data LAC incidence was lower overall, except for leukemia and lymphoma at age 0-14 years and the other and unspecified tumors at any age. Overall incidence at age 0-19 years increased by 1.0% per year (95% CI [0.6, 1.3]) over 1993-2012. The included registries covered 16% of population aged 0-14 years and 10% of population aged 15-19 years. Conclusions. The observed patterns provide a baseline to assess the status and evolution of childhood cancer occurrence in the region. Extended and sustained support of cancer registration is required to improve representativeness and timeliness of data for childhood cancer control in LAC.


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RESUMO Objetivo. Apresentar uma visão abrangente dos padrões geográficos (2001 a 2010) e das tendências temporais (1993 a 2012) da incidência de câncer em crianças e jovens de 0 a 19 anos na América Latina e no Caribe (ALC) e interpretar os resultados no contexto de padrões mundiais. Métodos. Foram descritas variações geográficas de 2001 a 2010 e tendências de incidência de 1993 a 2012 na população com menos de 20 anos da ALC usando informações comparáveis da base de dados do terceiro volume do estudo International Incidence of Childhood Cancer. Foram calculadas taxas de incidência específica por idade por milhão de pessoas-ano (ASR, na sigla em inglês) para subgrupos populacionais e taxas padronizadas por idade usando a população padrão mundial (WSR, na sigla em inglês). Resultados. No total, foram incluídos 36 744 casos únicos. No período de 2001 a 2010, a WSR para todos os tumores combinados na faixa etária de 0 a 14 anos foi de 132,6. Os diagnósticos mais frequentes foram leucemia (WSR de 48,7), neoplasias do sistema nervoso central (WSR de 23,0) e linfoma (WSR de 16,6). A ASR para todos os tumores combinados na faixa etária de 15 a 19 anos foi de 152,3, e a maior taxa foi a de linfoma (ASR de 30,2). A incidência foi maior no sexo masculino do que no sexo feminino e maior na América do Sul do que na América Central e no Caribe. De modo geral, em comparação com as estimativas mundiais, a incidência na ALC foi menor, exceto para leucemia e linfoma entre 0 e 14 anos e para outros tumores e tumores não especificados em qualquer idade. A taxa de incidência na faixa etária de 0 a 19 anos aumentou em 1,0% ao ano (IC de 95% [0,6, 1,3]) entre 1993 e 2012. Os registros incluídos cobriam 16% da população de 0 a 14 anos e 10% da população de 15 a 19 anos. Conclusões. Os padrões observados servem de referência para avaliar o status e a evolução da ocorrência de câncer infantil na região. É necessário garantir um apoio ampliado e consistente aos registros de câncer para aprimorar a representatividade e a disponibilidade das informações em tempo adequado para o controle do câncer infantil na ALC.

4.
Dis Model Mech ; 16(9)2023 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-37681401

RESUMEN

Despite the clear benefit of studying biological samples from diverse genetic backgrounds and geographical locations, our current knowledge of disease is mostly derived from the study of European-descent individuals. In the cancer field, this is reflected in the poor representation of African and Amerindian/Latino samples in most large public data repositories. This lack of diversity is due to several reasons, but here we focus on (1) the lack of support for studies on non-European populations that are performed in low- and middle-income countries (LMICs), and (2) unequal partnerships between scientists in LMICs and those in high-income countries. We argue that expanding access to research funding, increasing the participation of underrepresented scientists in editorial boards and international conferences, facilitating the publication of studies conducted in these countries, and properly acknowledging LMIC researchers' contributions in publications and grant applications will promote equity for scientists working in LMICs. We envisage that this will translate to more impactful research in these countries, which will include more samples from diverse populations. For the cancer field, this will broaden our understanding of pathomechanisms and may help to improve the treatment of patients from all backgrounds.


Asunto(s)
Neoplasias , Investigación , Humanos , Investigadores , Antecedentes Genéticos , Neoplasias/genética
5.
Phys Rev Lett ; 131(5): 051201, 2023 Aug 04.
Artículo en Inglés | MEDLINE | ID: mdl-37595214

RESUMEN

We report the first detection of a TeV γ-ray flux from the solar disk (6.3σ), based on 6.1 years of data from the High Altitude Water Cherenkov (HAWC) observatory. The 0.5-2.6 TeV spectrum is well fit by a power law, dN/dE=A(E/1 TeV)^{-γ}, with A=(1.6±0.3)×10^{-12} TeV^{-1} cm^{-2} s^{-1} and γ=3.62±0.14. The flux shows a strong indication of anticorrelation with solar activity. These results extend the bright, hard GeV emission from the disk observed with Fermi-LAT, seemingly due to hadronic Galactic cosmic rays showering on nuclei in the solar atmosphere. However, current theoretical models are unable to explain the details of how solar magnetic fields shape these interactions. HAWC's TeV detection thus deepens the mysteries of the solar-disk emission.

6.
Steroids ; 196: 109248, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37169217

RESUMEN

Five new brassinosteroid analogues were synthetized from 3ß-acetoxy-23,24-dinorchol-4-en-22-oic acid. All the obtained compound showed significant activity in the Rice Lamina Inclination Test. Interestingly the effects of the methyl ester of 3ß-hydroxy-6-oxo-23,24-dinorcholan-22-oic acid (14) at concentrations of 1 × 10-7 and 1 × 10-6 M proved to be higher than those produced by brassinolide. In silico Molecular Docking and Induced fit docking (IFD) simulations for the compounds with the highest biological activity data were carried out to investigate the binding mode interactions into the brassinolide-binding groove which revealed that the compound 14 had high binding energy values and a good affinity.


Asunto(s)
Brasinoesteroides , Ésteres , Brasinoesteroides/farmacología , Simulación del Acoplamiento Molecular , Factores de Crecimiento Nervioso
7.
J Neurol Psychol ; 10(1)2023.
Artículo en Inglés | MEDLINE | ID: mdl-37206541

RESUMEN

Background: Depression is a debilitating and difficult-to-treat condition in people with HIV (PWH) despite viral suppression on antiretroviral therapy (ART). Depression is associated with activation of the PKR-like ER kinase (PERK) pathway, which regulates protein synthesis in response to metabolic stress. We evaluated common PERK haplotypes that influence PERK expression in relation to depressed mood in PWH. Methods: PWH from 6 research centers were enrolled in the study. Genotyping was conducted using targeted sequencing with TaqMan. The major PERK haplotypes A, B, and D were identified. Depressive symptom severity was assessed using the Beck Depression Inventory-II (BDI-II). Covariates including genetically-defined ancestry, demographics, HIV disease/treatment parameters and antidepressant treatments were assessed. Data were analyzed using multivariable regression models. Results: A total of 287 PWH with a mean (SD) age of 57.1±7.8 years were enrolled. Although the largest ethnic group was non-Hispanic white (n=129, 45.3%), African-American (n=124, 43.5%) and Hispanic (n=30, 10.5%) made up over half the sample. 20.3% were female and 96.5% were virally suppressed. Mean BDI-II was 9.6±9.5, and 28.9% scored above the cutoff for mild depression (BDI-II>13). PERK haplotype frequencies were AA57.8%, AB25.8%, AD 10.1%, and BB4.88%. PERK haplotypes were differentially represented according to genetic ancestry (p=6.84e-6). BDI-II scores were significantly higher in participants with the AB haplotype (F=4.45, p=0.0007).This finding was robust to consideration of potential confounds. Conclusion: PERK haplotypes were associated with depressed mood in PWH.Consequently, pharmacological targeting of PERK-related pathways might amelioratedepression in PWH.

8.
Sci Total Environ ; 872: 162220, 2023 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-36796694

RESUMEN

An intertidal fish assemblage was studied in central Chile for 15 years in three localities: Isla Negra, El Tabo, and Las Cruces. Analyses of their multivariate dissimilarities were carried out considering temporal and spatial factors. Temporal factors included intra-annual and year-to-year variability. Spatial factors included locality, intertidal tidepool height, and each tidepool considered as a unique unit. Complementary to this, we tested the hypothesis that the El Niño Southern Oscillation (ENSO) would help explain year-to-year dissimilarities in the multivariate structure of this fish assemblage for the 15 years of data. To this end, the ENSO was regarded as a continuous inter-annual process as well as a set of discrete events. Additionally, dissimilarities in the temporal dynamics of the fish assemblage were evaluated considering each locality and tidepool unique units. Results indicated the following: (i) The most representative species for the whole area and period of the study were Scartichthys viridis (44 %), Helcogrammoides chilensis (17 %), Girella laevifrons (10 %), Graus nigra (7 %), Auchenionchus microcirrhis (5 %), and Helcogrammoides cunninghami (4 %); (ii) there is intra-annual (i.e., seasonality) and year-to-year multivariate variability in fish assemblage dissimilarities throughout the entire area of study, including all the tidepools and localities; (iii) when considering the spatial factor specifically, each tidepool unit, as well as their heights and localities, presented their own unique temporal year-to-year dynamics. The latter can be explained by the ENSO factor, also considering the intensity of the El Niño and La Niña events. In summary, the multivariate structure of the intertidal fish assemblage was statistically dissimilar when comparing neutral periods with El Niño and La Niña events. This structure was observed for the entire area of study, for each locality, and primarily for each tidepool as a unique unit. Fish physiological mechanisms underlying the identified patterns are discussed.


Asunto(s)
Ecosistema , El Niño Oscilación del Sur , Animales , Océano Pacífico , Peces , Regiones Antárticas
9.
Oper Dent ; 46(1): 4-14, 2021 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-33882132

RESUMEN

CLINICAL RELEVANCE: Lithium disilicate veneers for esthetic restorations show great accuracy and similarity, regardless of the type of fabrication technique.


Asunto(s)
Cerámica , Calor , Diseño Asistido por Computadora , Coronas , Porcelana Dental , Diseño de Prótesis Dental , Ensayo de Materiales
11.
Rev Esp Quimioter ; 34(1): 12-17, 2021 Feb.
Artículo en Español | MEDLINE | ID: mdl-33210107

RESUMEN

OBJECTIVE: The increase in infections with multidrug resistant bacteria has forced to return to the use of colistin, antibiotic with known nephrotoxicity. The aim of the study is to determine the incidence of colistin nephrotoxicity nowadays. METHODS: Retrospective-observational-unicentric study was collected hospitalized patients in intravenous colistin treatment during the years 2018-2019. Nephrotoxicity was defined according to the RIFLE scale. The variables to determine it were serum creatinine (sCr) and glomerular filtration (GF). The variables analyzed were age, sex, treatment duration, loading and cumulative dose, empirical/targeted treatment, chronic kidney disease, concomitant use of intravenous contrast and nephrotoxic drugs. RESULTS: A total of 90 patients (60% men) were included, with an average age of 58.2±18.1 years. The mean duration of treatment was 9±8.3 days, with an average cumulative dose of 69.8±71MU. There were no differences between sCr and GF at the beginning and end of treatment. The incidence of nephrotoxicity was 1.73 cases/100 days of treatment (prevalence of 15.56%). CONCLUSIONS: Colistin nephrotoxicity has an important incidence, without developing severe illness.


Asunto(s)
Antibacterianos , Colistina , Adulto , Anciano , Antibacterianos/efectos adversos , Colistina/efectos adversos , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Riesgo
12.
J Healthc Qual Res ; 35(5): 313-318, 2020.
Artículo en Español | MEDLINE | ID: mdl-32737015

RESUMEN

BACKGROUND AND OBJECTIVES: Medication errors are the most common adverse events in healthcare. Pharmaceutical validation (PV) seeks to reduce them. The aims of this study were to assess the impact of the introduction of an automated tool for the validation (VPAT) of the high clinical relevance drugs prescription (HCRD) over time of pharmaceutical intervention (PI), and to quantify the number of medication errors detected before and after its implementation. MATERIAL AND METHODS: A two phase retrospective-observational single centre study was designed. A pre-intervention phase (Pre-P): PV of beds with Unit Dose Dispensing (October 2015 - February 2016), was followed by a post-intervention phase (Post-P): PV using a VPAT of HCRD in hospital patients (October 2016 - February 2017). HCRD were selected from the list of high-risk drugs of Institute for Safe Medication Practices. The data was obtained from the PI record (Access®) and the computerised prescription. The variables collected were: age and gender of the patients included, data of drugs prescription, and time to PI. RESULTS: A total of 477 PI were analysed in 404 patients, with a mean age of 65.9±19.5 years (53.22% women). The mean time up to PI was 25.6±24.72h in the Pre-P, and 18.87±20.44h in the Post-P (P=0.01). In Pre-P, 106 PI were performed (35.85% prevention of adverse reactions) compared to 371 PI (39.62% medication reconciliation) in Post-P. CONCLUSIONS: The VPAT enabled a greater number of medication errors to be detected and intervened in hospitalised patients, with a significantly reduced time to PI.


Asunto(s)
Errores de Medicación , Mejoramiento de la Calidad , Anciano , Anciano de 80 o más Años , Prescripciones de Medicamentos , Femenino , Humanos , Masculino , Errores de Medicación/prevención & control , Conciliación de Medicamentos , Persona de Mediana Edad , Estudios Retrospectivos
13.
Oper Dent ; 45(5): 457b-466, 2020 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-32243251

RESUMEN

CLINICAL RELEVANCE: This article presents the dental restoration of a young female patient complaining of erosive dental wear using a three-step restorative technique, an alternative approach with some novel adjustments. SUMMARY: For successful tooth wear treatment, determining the etiological systemic and local factors is the main priority before deciding on effective and long-term preventive and/or therapeutic restorative approaches. In addition to professional intervention, achieving optimal outcomes requires patients to control their diet and/or gastric issues, thus minimizing the wear process. However, continuous wear constitutes the most challenging scenario, mainly when it affects young patients' dentitions. This article describes the dental restoration of posterior teeth with reestablishment of occlusal vertical dimension before treating the anterior teeth, while educating the patient and providing medical monitoring. The three-step restorative technique seems to be properly applicable in cases of significant dental compromise due mainly to erosive wear and is based on direct procedures, which can assure a reliable and feasible approach.


Asunto(s)
Desgaste de los Dientes , Restauración Dental Permanente , Dieta , Femenino , Humanos , Desgaste de los Dientes/terapia , Dimensión Vertical
14.
Phys Rev Lett ; 124(13): 131101, 2020 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-32302173

RESUMEN

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.

15.
Phys Rev Lett ; 124(2): 021102, 2020 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-32004015

RESUMEN

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.

17.
Am J Surg ; 218(5): 918-927, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-30853093

RESUMEN

BACKGROUND: Aim of the study was to describe characteristics and outcomes of Hartmann's procedure (HP) and subsequent intestinal restoration. METHODS: Retrospective study including all patients who underwent HP over a period of 16 consecutive years. We propose a classification and regression tree for a more accurate view of the relationship between the variables related to intestinal restoration and their weighting in the decision to reverse HP. RESULTS: 533 patients were included. Overall morbidity rate of HP was 53.5% and mortality 21.0%. Overall morbidity of the intestinal continuity reconstruction was 47.3% and mortality 0.9%. Patients with a benign disease, aged under 69 years and with low comorbidity, had an 84.4% probability of undergoing intestinal reconstruction. CONCLUSIONS: HP is associated with high morbidity and mortality. Restoration of intestinal continuity involves minor, but frequent, morbidity and a low mortality rate. Age and comorbidities can decrease, and even override, the decision to reverse HP.


Asunto(s)
Colon Descendente/cirugía , Colon Sigmoide/cirugía , Enfermedades del Colon/cirugía , Recto/cirugía , Anciano , Anciano de 80 o más Años , Anastomosis Quirúrgica , Colectomía/efectos adversos , Colectomía/métodos , Colostomía/efectos adversos , Colostomía/métodos , Femenino , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Proctectomía/efectos adversos , Proctectomía/métodos , Estudios Retrospectivos , Resultado del Tratamiento
18.
Br J Dermatol ; 181(1): 105-113, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-30451293

RESUMEN

BACKGROUND: Germline mutations in telomere-related genes such as POT1 and TERT predispose individuals to familial melanoma. OBJECTIVES: To evaluate the prevalence of germline mutations in POT1 and TERT in a large cohort of Spanish melanoma-prone families (at least two affected first- or second-degree relatives). METHODS: Overall, 228 CDKN2A wild-type melanoma-prone families were included in the study. Screening of POT1 was performed in one affected person from each family and TERT was sequenced in one affected patient from 202 families (26 families were excluded owing to DNA exhaustion/degradation). TERT promoter sequencing was extended to an additional 30 families with CDKN2A mutation and 70 patients with sporadic multiple primary melanoma (MPM) with a family history of other cancers. RESULTS: We identified four families with potentially pathogenic POT1 germline mutations: a missense variant c.233T>C (p.Ile78Thr); a nonsense variant c.1030G>T (p.Glu344*); and two other variants, c.255G>A (r.125_255del) and c.1792G>A (r.1791_1792insAGTA, p.Asp598Serfs*22), which we confirmed disrupted POT1 mRNA splicing. A TERT promoter variant of unknown significance (c.-125C>A) was detected in a patient with MPM, but no germline mutations were detected in TERT promoter in cases of familial melanoma. CONCLUSIONS: Overall, 1·7% of our CDKN2A/CDK4-wild type Spanish melanoma-prone families carry probably damaging mutations in POT1. The frequency of TERT promoter germline mutations in families with melanoma in our population is extremely rare.


Asunto(s)
Predisposición Genética a la Enfermedad , Melanoma/genética , Regiones Promotoras Genéticas/genética , Neoplasias Cutáneas/genética , Telomerasa/genética , Proteínas de Unión a Telómeros/genética , Adulto , Anciano , Codón sin Sentido , Estudios de Cohortes , Inhibidor p16 de la Quinasa Dependiente de Ciclina/genética , Análisis Mutacional de ADN , Femenino , Pruebas Genéticas , Mutación de Línea Germinal , Humanos , Masculino , Anamnesis , Melanoma/epidemiología , Persona de Mediana Edad , Mutación , Mutación Missense , Linaje , Complejo Shelterina , Neoplasias Cutáneas/epidemiología , España/epidemiología , Melanoma Cutáneo Maligno
20.
Nature ; 562(7725): 82-85, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-30283106

RESUMEN

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.

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