Range-wide genetic structure in the thorn-tailed rayadito suggests limited gene flow towards peripheral populations

Indexación ScopusUnderstanding the population genetic consequences of habitat heterogeneity requires assessing whether patterns of gene flow correspond to landscape configuration. Studies of the genetic structure of populations are still scarce for Neotropical forest birds. We assessed range-wide genetic structure and contemporary gene flow in the thorn-tailed rayadito (Aphrastura spinicauda), a passerine bird inhabiting the temperate forests of South America. We used 12 microsatellite loci to genotype 582 individuals from eight localities across a large latitudinal range (30°S–56°S). Using population structure metrics, multivariate analyses, clustering algorithms, and Bayesian methods, we found evidence for moderately low regional genetic structure and reduced gene flow towards the range margins. Genetic differentiation increased with geographic distance, particularly in the southern part of the species’ distribution where forests are continuously distributed. Populations in the north seem to experience limited gene flow likely due to forest discontinuity, and may comprise a demographically independent unit. The southernmost population, on the other hand, is genetically depauperate and different from all other populations. Different analytical approaches support the presence of three to five genetic clusters. We hypothesize that the genetic structure of the species follows a hierarchical clustered pattern. © 2020, The Author(s).https://www-nature-com.recursosbiblioteca.unab.cl/articles/s41598-020-66450-

Tocilizumab in patients admitted to hospital with COVID-19 (RECOVERY): a randomised, controlled, open-label, platform trial

Background: In this study, we aimed to evaluate the effects of tocilizumab in adult patients admitted to hospital with COVID-19 with both hypoxia and systemic inflammation. Methods: This randomised, controlled, open-label, platform trial (Randomised Evaluation of COVID-19 Therapy [RECOVERY]), is assessing several possible treatments in patients hospitalised with COVID-19 in the UK. Those trial participants with hypoxia (oxygen saturation <92% on air or requiring oxygen therapy) and evidence of systemic inflammation (C-reactive protein ≥75 mg/L) were eligible for random assignment in a 1:1 ratio to usual standard of care alone versus usual standard of care plus tocilizumab at a dose of 400 mg–800 mg (depending on weight) given intravenously. A second dose could be given 12–24 h later if the patient's condition had not improved. The primary outcome was 28-day mortality, assessed in the intention-to-treat population. The trial is registered with ISRCTN (50189673) and ClinicalTrials.gov (NCT04381936). Findings: Between April 23, 2020, and Jan 24, 2021, 4116 adults of 21 550 patients enrolled into the RECOVERY trial were included in the assessment of tocilizumab, including 3385 (82%) patients receiving systemic corticosteroids. Overall, 621 (31%) of the 2022 patients allocated tocilizumab and 729 (35%) of the 2094 patients allocated to usual care died within 28 days (rate ratio 0·85; 95% CI 0·76–0·94; p=0·0028). Consistent results were seen in all prespecified subgroups of patients, including those receiving systemic corticosteroids. Patients allocated to tocilizumab were more likely to be discharged from hospital within 28 days (57% vs 50%; rate ratio 1·22; 1·12–1·33; p<0·0001). Among those not receiving invasive mechanical ventilation at baseline, patients allocated tocilizumab were less likely to reach the composite endpoint of invasive mechanical ventilation or death (35% vs 42%; risk ratio 0·84; 95% CI 0·77–0·92; p<0·0001). Interpretation: In hospitalised COVID-19 patients with hypoxia and systemic inflammation, tocilizumab improved survival and other clinical outcomes. These benefits were seen regardless of the amount of respiratory support and were additional to the benefits of systemic corticosteroids. Funding: UK Research and Innovation (Medical Research Council) and National Institute of Health Research

Convalescent plasma in patients admitted to hospital with COVID-19 (RECOVERY): a randomised controlled, open-label, platform trial

Background: Many patients with COVID-19 have been treated with plasma containing anti-SARS-CoV-2 antibodies. We aimed to evaluate the safety and efficacy of convalescent plasma therapy in patients admitted to hospital with COVID-19. Methods: This randomised, controlled, open-label, platform trial (Randomised Evaluation of COVID-19 Therapy [RECOVERY]) is assessing several possible treatments in patients hospitalised with COVID-19 in the UK. The trial is underway at 177 NHS hospitals from across the UK. Eligible and consenting patients were randomly assigned (1:1) to receive either usual care alone (usual care group) or usual care plus high-titre convalescent plasma (convalescent plasma group). The primary outcome was 28-day mortality, analysed on an intention-to-treat basis. The trial is registered with ISRCTN, 50189673, and ClinicalTrials.gov, NCT04381936. Findings: Between May 28, 2020, and Jan 15, 2021, 11558 (71%) of 16287 patients enrolled in RECOVERY were eligible to receive convalescent plasma and were assigned to either the convalescent plasma group or the usual care group. There was no significant difference in 28-day mortality between the two groups: 1399 (24%) of 5795 patients in the convalescent plasma group and 1408 (24%) of 5763 patients in the usual care group died within 28 days (rate ratio 1·00, 95% CI 0·93–1·07; p=0·95). The 28-day mortality rate ratio was similar in all prespecified subgroups of patients, including in those patients without detectable SARS-CoV-2 antibodies at randomisation. Allocation to convalescent plasma had no significant effect on the proportion of patients discharged from hospital within 28 days (3832 [66%] patients in the convalescent plasma group vs 3822 [66%] patients in the usual care group; rate ratio 0·99, 95% CI 0·94–1·03; p=0·57). Among those not on invasive mechanical ventilation at randomisation, there was no significant difference in the proportion of patients meeting the composite endpoint of progression to invasive mechanical ventilation or death (1568 [29%] of 5493 patients in the convalescent plasma group vs 1568 [29%] of 5448 patients in the usual care group; rate ratio 0·99, 95% CI 0·93–1·05; p=0·79). Interpretation: In patients hospitalised with COVID-19, high-titre convalescent plasma did not improve survival or other prespecified clinical outcomes. Funding: UK Research and Innovation (Medical Research Council) and National Institute of Health Research

Análisis del caudal de aire en un disco de freno automotriz con perfiles de ventilación tipo N-38

The braking system of a car must meet a complex set of requirements, with safety being the most important. In the design of these systems, it directly influences a correct geometry and an adequate selection of the material for its correct operation. The objective of this work is to propose a new geometric arrangement for the optimization of airflow in an automotive brake disc, taking into account the ventilation pillars based on aerodynamic profiles type N-38. In the validation of this design proposal, a 1:1 scale prototype was built by means of additive manufacturing and thus be able to measure the field of generating speeds in the suction and discharge zone using Particle Image Velocimetry (VIP). The geometric arrangement was carried out under two angular velocity conditions: 541 and 941 rpm. The results showed the optimization of the air velocity in the discharge zone of 0.2121 and 0.743 m/s respectively for the speed ranges; which demonstrates the importance of experimental designs with which the geometry of self-ventilated disc brakes can be improved and thus the efficiency and safety of the system are required.El sistema de frenado de un automóvil debe satisfacer un conjunto complejo de requerimientos, siendo la seguridad lo más importante. En el diseño de estos sistemas, influye directamente una correcta geometría y una selección adecuada del material para garantizar su correcto funcionamiento. El objetivo de este trabajo, es proponer un nuevo arreglo geométrico para la optimización del flujo de aire en un disco de freno automotriz, teniendo en cuenta pilares de ventilación fundamentado en perfiles aerodinámicos tipo N-38. Para validar esta propuesta de diseño, fue construido un prototipo a escala 1:1 por medio de manufactura aditiva y de esta manera poder medir el campo de velocidades generado en la zona de succión y descarga utilizando Velocimetría por Imágenes de Partícula (VIP). El arreglo geométrico se llevó a cabo bajo dos condiciones de velocidad angular: 541 y 941 rpm. Los resultados obtenidos muestran la optimización de la velocidad del aire en la zona de descarga de 0.2121 y 0.743 m/s respectivamente para los rangos de velocidades; con lo que se evidencio la importancia de diseños experimentales con los cuales se pueda mejorar la geometría de los frenos de disco autoventilados y de esta manera garantizar la eficiencia y seguridad del sistema

Complete multilineage CD4 expression defect associated with warts due to an inherited homozygous CD4 gene mutation

On behalf of the EuroFlow Consortium.Idiopathic T-CD4 lymphocytopenia (ICL) is a rare and heterogeneous syndrome characterized by opportunistic infections due to reduced CD4 T-lymphocytes (<300 cells/μl or <20% T-cells) in the absence of HIV infection and other primary causes of lymphopenia. Molecular testing of ICL has revealed defects in genes not specific to CD4 T-cells, with pleiotropic effects on other cell types. Here we report for the first time an absolute CD4 lymphocytopenia (<0.01 CD4+ T-cells/μl) due to an autosomal recessive CD4 gene mutation that completely abrogates CD4 protein expression on the surface membrane of T-cells, monocytes, and dendritic cells. A 45-year-old female born to consanguineous parents consulted because of exuberant, relapsing, and treatment-refractory warts on her hands and feet since the age of 10 years, in the absence of other recurrent infections or symptoms. Serological studies were negative for severe infections, including HIV 1/2, HTLV-1, and syphilis, but positive for CMV and EBV. Blood analysis showed the absence of CD4+ T-cells (<0.01%) with repeatedly increased counts of B-cells, naïve CD8+ T-lymphocytes, and particularly, CD4/CD8 double-negative (DN) TCRαβ+ TCRγδ− T-cells (30% of T-cells; 400 cells/μl). Flow cytometric staining of CD4 using monoclonal antibodies directed against five different epitopes, located in two different domains of the protein, confirmed no cell surface membrane or intracytoplasmic expression of CD4 on T-cells, monocytes, and dendritic cells but normal soluble CD4 plasma levels. DN T-cells showed a phenotypic and functional profile similar to normal CD4+ T-cells as regards expression of maturation markers, T-helper and T-regulatory chemokine receptors, TCRvβ repertoire, and in vitro cytokine production against polyclonal and antigen-specific stimuli. Sequencing of the CD4 gene revealed a homozygous (splicing) mutation affecting the last bp on intron 7–8, leading to deletion of the juxtamembrane and intracellular domains of the protein and complete abrogation of CD4 expression on the cell membrane. These findings support previous studies in CD4 KO mice suggesting that surrogate DN helper and regulatory T-cells capable of supporting antigen-specific immune responses are produced in the absence of CD4 signaling and point out the need for better understanding the role of CD4 on thymic selection and the immune response.EB was supported by a grant from the Junta de Castilla y León (Fondo Social Europeo, ORDEN EDU/346/2013, Valladolid, Spain). This work was supported by: the CB16/12/00400 grant (CIBERONC, Instituto de Salud Carlos III, Ministerio de Economía y Competitividad, Madrid, Spain and FONDOS FEDER), the FIS PI12/00905-FEDER grant (Fondo de Investigación Sanitaria of Instituto de Salud Carlos III, Madrid, Spain), and a grant from Fundación Mutua Madrileña (Madrid, Spain).Peer reviewe

Clinical case series: Sedoanalgesia for thoracoscopic procedures

Thoracoscopy is a procedure increasingly used because it is minimally invasive and assists in the diagnosis and treatment of different types of pathologies. The anaesthetic technique has evolved over time. In the beginning it was necessarily invasive, by selective or non-selective intubation; now it is non-invasive with appropriate regional anaesthesia and intravenous analgesia/sedation in selected cases. At the Hospital General de México “Dr. Eduardo Liceaga”, in a significant proportion of cases thoracoscopy is currently done with the patient awake so we consider it necessary to report some of these cases along with the results obtained. Resumen: La toracoscopia es un procedimiento cada vez más utilizado al ser poco invasivo y coadyuvar en el diagnóstico y tratamiento de diferentes tipos de patologías. La técnica anestésica ha evolucionado con el paso de tiempo de ser necesariamente invasiva, mediante la intubación selectiva o no selectiva, a ser no invasiva con una adecuada anestesia regional y analgesia/sedación intravenosa en casos seleccionados. En el Hospital General de México “Dr. Eduardo Liceaga” actualmente se realiza la toracoscopia con el paciente despierto en una proporción importante de casos por lo que consideramos necesario reportar algunos de estos casos acompañados de los resultados obtenidos. Keywords: Anaesthesia, Thoracoscopy, Sedation, Palabras clave: Anestesia, Toracoscopia, Sedació

Levels of Organochlorine Pesticides in Blood Plasma from Residents of Malaria-Endemic Communities in Chiapas, Mexico

Organochlorine (OC) pesticides have been extensively used for pest control in agriculture and against malaria vectors in the region of Soconusco, Chiapas, in southern Mexico. Our study aimed to identify whether the inhabitants of four Soconusco communities at different locations (i.e., altitudes) and with different history of use of OC pesticides, have been similarly exposed to residues of these pesticides. In particular, we analyzed the potential relationship between levels of OC pesticides in plasma and the age, gender, and residence of the study population (n = 60). We detected seven pesticides in total (gamma-HCH, beta-HCH, heptachlor, p,p'-DDE, p,p'-DDT, beta-endosulfan, endrin aldehyde). Of these, p,p'-DDE and beta-endosulfan were the most frequently found (in 98% and 38% of the samples, respectively). The low-altitude (60 years) had the highest p,p'-DDE level (56.94 +/- 57.81 mu g/L) of all age groups, while men had higher p,p'-DDE (34.00 +/- 46.76 mu g/L) than women. Our results demonstrate that residents of the Soconusco region are exposed to p,p'-DDE because of high exposure to DDT in the past and current environmental exposure to this DDT-breakdown product