163 research outputs found
Efficacy of antiplatelet therapy in secondary prevention following lacunar stroke:Pooled analysis of randomized trials
Background and Purpose: Lacunar stroke accounts for ≈25% of ischemic stroke, but optimal antiplatelet regimen to prevent stroke recurrence remains unclear. We aimed to evaluate the efficacy of antiplatelet agents in secondary stroke prevention after a lacunar stroke. Methods: We searched MEDLINE, Embase, and the Cochrane library for randomized controlled trials that reported risk of recurrent stroke or death with antiplatelet therapy in patients with lacunar stroke. We used random effects meta-analysis and evaluated heterogeneity with I2. Results: We included 17 trials with 42 234 participants (mean age 64.4 years, 65% male) and follow up ranging from 4 weeks to 3.5 years. Compared with placebo, any single antiplatelet agent was associated with a significant reduction in recurrence of any stroke (risk ratio [RR] 0.77, 0.62–0.97, 2 studies) and ischemic stroke (RR 0.48, 0.30–0.78, 2 studies), but not for the composite outcome of any stroke, myocardial infarction, or death (RR 0.89, 0.75–1.05, 2 studies). When other antiplatelet agents (ticlodipine, cilostazol, and dipyridamole) were compared with aspirin, there was no consistent reduction in stroke recurrence (RR 0.91, 0.75–1.10, 3 studies). Dual antiplatelet therapy did not confer clear benefit over monotherapy (any stroke RR 0.83, 0.68–1.00, 3 studies; ischemic stroke RR 0.80, 0.62–1.02, 3 studies; composite outcome RR 0.90, 0.80–1.02, 3 studies). Conclusions: Our results suggest that any of the single antiplatelet agents compared with placebo in the included trials is adequate for secondary stroke prevention after lacunar stroke. Dual antiplatelet therapy should not be used for long-term stroke prevention in this stroke subtype
Crystal and anion structure, TGA, DTA, and infrared and Raman spectra of managanese(II) nitroprusside dihydrate, Mn [Fe(CN)5NO]·2H2O
The single crystal and anion structure of Mn[Fe(CN)5NO·2H2O, obtained by slow interdiffusion of reactant solutions through a TMS gel, was solved by X-ray diffraction methods and refined toR1=0.036. Spatial group: orthorhombic, Pnma, a=14.069(2), b=7.538(1), c=10.543(1)A, Z=4. The Mn(II) ion and the water molecules are sited on mirror planes, which bisect the nitroprusside ions. One of the water molecules is coordinated to Mn(II) and the other, strongly hydrogen (as acceptor) bonded to the first molecule. The IR spectrum confirms the bonding of the water molecules and TGA results are in accordance with the dihydrate character of the substance and its dehydration in two successive steps. DTA results and the Raman spectrum agree with other results and the comparison between IR and Raman vNO wavenumbers confirms the expected strong vibrational interaction between the closely packed antiparallel (eclipsed) NO groups. There is a topotactic relationship between the dihydrate and the trihydrate, which crystallizes in the space subgroupP2; 1/n.Centro de Química Inorgánic
SISTEMA DE ACTIVIDADES FÍSICAS PARA LA FORMACIÓN BÁSICA EN LA NATACIÓN CON NIÑOS SÍNDROME DE DOWN DE 5 Y 6 AÑOS DEL MUNICIPIO CIEGO DE ÁVILA / SYSTEM OF PHYSICAL ACTIVITIES FOR BASIC TRAINING IN SWIMMING WITH CHILDREN DOWN SYNDROME OF 5 AND 6 YEARS OF THE CIEGO MUNICIPALITY OF ÁVILA
El avance del deporte de natación en el Municipio y las ofertas que tiene el Sistema del INDER para la enseñanza del deporte en niños síndrome de Down no es acorde a su patología, se realiza la presente investigación titulada: Sistema de actividades físicas para la formación básica en la natación con niños síndrome de Down de 5 y 6 años del municipio Ciego de Ávila, en un primer momento se aborda los diferentes teóricos generales que fueron necesarios para la elaboración del sistema. Se realizó el diagnóstico con la población y la utilización de los métodos investigativos del nivel teórico y empírico; contiene el diagnóstico del estado inicial de la enseñanza de la natación que permitieron el análisis de los resultados, desde la situación real encontrada en el proceso de enseñanza de la natación en niños síndrome de Down del Municipio, se precisan los ejercicios y juegos concebidos en el sistema de actividades y su evaluación final después de ponerse en práctica.
High Efficiency Power Amplifier Based on Envelope Elimination and Restoration Technique
Due to complex envelope and phase modulation employed in modern transmitters it is necessary to use power amplifiers that have high linearity. Linear power amplifiers (classes A, B and AB) are commonly used, but they suffer from low efficiency especially if the transmitted signal has high peak to average power ratio (PAPR). Kahn's technique based on envelope elimination and restoration (EER) is based on idea that high efficiency power supply (envelope amplifier) could be used to modulate the envelope of high efficient non linear power amplifiers (classes D or E). This paper presents solutions for power amplifier that performs envelope modulation and class E amplifier that is used as a non linear amplifier. The envelope amplifier is implemented as a multilevel converter in series with linear regulator and can provide up to 100 W of instantaneous power and reproduce 2 MHz sine wave. The implemented Class E amplifier can operate at 120 MHz with efficiency near to 85%. The envelope amplifier and class E amplifier have been integrated and efficiency and linearity of the implemented transmitter has been measured and presente
Design and use of an evaluation tool for assessment of instrumental skills within a subject related to materials science
[Otros] The interest in a competence-based approach in the university, continues increasing at a considerable rate in the European Higher Education Area. Generic competences (specific of the sort of education) assessment is nowadays considered crucial to support socio-educational demands. Nevertheless, the methodologies for the assessment/evaluation of the generic competences and their inclusion in the curriculum has yet to be adequately achieved. Competency-based learning requires either the development of new evaluation tools or adjustment of the existing ones in order to support marking changes needed for new learning-oriented active methodologies. In this sense, questionnaires are an innovative educational tool for competence evaluation although the development of a solid body of knowledge is still a pending task.
For this reason, this study proposes a methodological tool based on a questionnaire for rating the assessment (or not) of Specific Instrumental generic competence (instrumental skills), as defined in our university, by undergraduate students. In this regard, a practical intervention was designed to integrate the evaluation of activities related to Instrumental Skills in undergraduate students of Chemical Engineering, taking advantage of a computer practice session programmed as a part of the Materials Science subject. The appropriateness of the developed questionnaire, based on some learning outcomes, as a tool to properly score the competence of interest has been analysed by comparison of the obtained marks with the ones coming from more regular evaluation tools. The results may lead to some interesting conclusions to university professors when creating appropriate competency-based scoring questionnaires.Authors gratefully acknowledge the financial support of the Vicerrectorado de Estudios, Calidad y
Acreditación and the Vicerrectorado de Recursos Digitales y Documentación of the Universitat
Politècnica de València (Project PIME B/19-20/165 and Project PIME C/20-21/201) and the Instituto de
Ciencias de la Educación of the Universitat Politècnica de València (EICE INTEGRAL).Andrés-Ruiz, VT.; Sonseca Olalla, A.; Sahuquillo, O.; Benavente Martínez, R. (2021). Design and use of an evaluation tool for assessment of instrumental skills within a subject related to materials science. IATED Academy. 3964-3970. https://doi.org/10.21125/edulearn.2021.0837S3964397
Determination of Diagnostic Reference Levels (DRLs) in General Radiographyin Latin America
The International Atomic Energy Agency (IAEA) through the International Action Plan on Radiation Protection of Patients and the International Commission on Radiological Protection have for some time carried out important efforts to assure that in the medical applications of the ionising radiations, the optimisation of radiological protection of patients is fundamental, to such a point that the IAEA includes it directly as a requirement for these practices (in its International Basic Safety Standards for Protection against Ionising Radiation and for the Safety of Radiation Sources (BSS)-GSR Part 1, 2011). For this reason, among the objectives of Regional Project RLA/9/057 and Regional Project RLA/9/067, the intention was to establish the dose references in conventional radiology for Latin America, for the purposes of determining whether these doses comply with the requirements of the BSS and to tend to improve practices, in order to minimise the dose received by the patients.Fil: Blanco, Susana Alicia Ana. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Belgrano. Facultad de Ingenieria; ArgentinaFil: Mora, Patricia. Centro de Investigación en Ciencias Atómicas, Nucleares y Moleculares; Costa RicaFil: Almonte, Narkiss. Comisión Nacional de Energía. Dirección Nuclear; República DominicanaFil: Benavente, Tony. Instituto Peruano de Energía Nuclear; PerúFil: Benson, Nadja. Ministerio de Salud. Dirección General de Salud; Reino UnidoFil: Blanco, Daniel. Universidad de la República. Centro de Investigaciones Nucleares; UruguayFil: Cárdenas, Juan. Centro de Protección e Higiene de las Radiaciones; CubaFil: Defaz Gómez, Yolanda. Hospital Oncológico SOLCA Nucleo de Quito; EcuadorFil: Edding, Oscar. Instituto de Salud Pública; ChileFil: Escobar, Carolina. Ministerio de Salud Pública y Acción Social. Unidad Reguladora de Radiaciones Ionizantes; El SalvadorFil: Fonseca, María. Hospital Nacional Roosevelt; GuatemalaFil: Gamarra, Mirta. Ministerio de Salud Pública y Bienestar Social; ParaguayFil: García Aguilar, Juan. Instituto Nacional de Investigaciones Nucleares; MéxicoFil: Khoury, Helen Jamil. Universidade Federal de Pernambuco; BrasilFil: Quintero, Ana Rosa. Hospital Oncológico "Dr Luis Razetti"; VenezuelaFil: Roas Zuniga, Norma. Universidad Nacional Autónoma de Nicaragua; NicaraguaFil: Zaire, Edgar. Instituto Boliviano de Ciencia y Tecnología Nuclear; BoliviaFil: Nader, Alejandro. International Atomic Energy Agency; Austri
Clinical significance of cerebral microbleeds on MRI
__Background:__ Cerebral microbleeds can confer a high risk of intracerebral hemorrhage, ischemic stroke, death and dementia, but estimated risks remain imprecise and often conflicting. We investigated the association between cerebral microbleeds presence and these outcomes in a large meta-analysis of all published cohorts including: ischemic stroke/TIA, memory clinic, “high risk” elderly populations, and healthy individuals in population-based studies.
__Methods:__ Cohorts (with > 100 participants) that assessed cerebral microbleeds presence on MRI, with subsequent follow-up (≥3 months) were identified. The association between cerebral microbleeds and each of the outcomes (ischemic stroke, intracerebral hemorrhage, death, and dementia) was quantified using random effects models of (a) unadjusted crude odds ratios and (b) covariate-adjusted hazard rations. Results: We identified 31 cohorts (n = 20,368): 19 ischemic stroke/TIA (n = 7672), 4 memory clinic (n = 1957), 3 high risk elderly (n = 1458) and 5 population-based cohorts (n = 11,722). Cerebral microbleeds were associated with an increased risk of ischemic stroke (OR: 2.14; 95% CI: 1.58–2.89 and adj-HR: 2.09; 95% CI: 1.71–2.57), but the relative increase in future intracerebral hemorrhage risk was greater (OR: 4.65; 95% CI: 2.68–8.08 and adj-HR: 3.93; 95% CI: 2.71–5.69). Cerebral microbleeds were an independent predictor of all-cause mortality (adj-HR: 1.36; 95% CI: 1.24–1.48). In three population-based studies, cerebral microbleeds were independently associated with incident dementia (adj-HR: 1.35; 95% CI: 1.00–1.82). Results were overall consistent in analyses stratified by different populations, but with different degrees of heterogeneity.
__Conclusions:__ Our meta-analysis shows that cerebral microbleeds predict an increased risk of stroke, death, and dementia and provides up-to-date effect sizes across different clinical settings. These pooled estimates can inform clinical decisions and trials, further supporting cerebral microbleeds role as biomarkers of underlying subclinical brain pathology in research and clinical settings
Effects of oral anticoagulation in people with atrial fibrillation after spontaneous intracranial haemorrhage (COCROACH): prospective, individual participant data meta-analysis of randomised trials
Background:
The safety and efficacy of oral anticoagulation for prevention of major adverse cardiovascular events in people with atrial fibrillation and spontaneous intracranial haemorrhage are uncertain. We planned to estimate the effects of starting versus avoiding oral anticoagulation in people with spontaneous intracranial haemorrhage and atrial fibrillation.
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Methods:
In this prospective meta-analysis, we searched bibliographic databases and trial registries using the strategies of a Cochrane systematic review (CD012144) on June 23, 2023. We included clinical trials if they were registered, randomised, and included participants with spontaneous intracranial haemorrhage and atrial fibrillation who were assigned to either start long-term use of any oral anticoagulant agent or avoid oral anticoagulation (ie, placebo, open control, another antithrombotic agent, or another intervention for the prevention of major adverse cardiovascular events). We assessed eligible trials using the Cochrane Risk of Bias tool. We sought data for individual participants who had not opted out of data sharing from chief investigators of completed trials, pending completion of ongoing trials in 2028. The primary outcome was any stroke or cardiovascular death. We used individual participant data to construct a Cox regression model of the time to the first occurrence of outcome events during follow-up in the intention-to-treat dataset supplied by each trial, followed by meta-analysis using a fixed-effect inverse-variance model to generate a pooled estimate of the hazard ratio (HR) with 95% CI. This study is registered with PROSPERO, CRD42021246133.
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Findings:
We identified four eligible trials; three were restricted to participants with atrial fibrillation and intracranial haemorrhage (SoSTART [NCT03153150], with 203 participants) or intracerebral haemorrhage (APACHE-AF [NCT02565693], with 101 participants, and NASPAF-ICH [NCT02998905], with 30 participants), and one included a subgroup of participants with previous intracranial haemorrhage (ELDERCARE-AF [NCT02801669], with 80 participants). After excluding two participants who opted out of data sharing, we included 412 participants (310 [75%] aged 75 years or older, 249 [60%] with CHA2DS2-VASc score ≤4, and 163 [40%] with CHA2DS2-VASc score >4). The intervention was a direct oral anticoagulant in 209 (99%) of 212 participants who were assigned to start oral anticoagulation, and the comparator was antiplatelet monotherapy in 67 (33%) of 200 participants assigned to avoid oral anticoagulation. The primary outcome of any stroke or cardiovascular death occurred in 29 (14%) of 212 participants who started oral anticoagulation versus 43 (22%) of 200 who avoided oral anticoagulation (pooled HR 0·68 [95% CI 0·42–1·10]; I2=0%). Oral anticoagulation reduced the risk of ischaemic major adverse cardiovascular events (nine [4%] of 212 vs 38 [19%] of 200; pooled HR 0·27 [95% CI 0·13–0·56]; I2=0%). There was no significant increase in haemorrhagic major adverse cardiovascular events (15 [7%] of 212 vs nine [5%] of 200; pooled HR 1·80 [95% CI 0·77–4·21]; I2=0%), death from any cause (38 [18%] of 212 vs 29 [15%] of 200; 1·29 [0·78–2·11]; I2=50%), or death or dependence after 1 year (78 [53%] of 147 vs 74 [51%] of 145; pooled odds ratio 1·12 [95% CI 0·70–1·79]; I2=0%).
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Interpretation:
For people with atrial fibrillation and intracranial haemorrhage, oral anticoagulation had uncertain effects on the risk of any stroke or cardiovascular death (both overall and in subgroups), haemorrhagic major adverse cardiovascular events, and functional outcome. Oral anticoagulation reduced the risk of ischaemic major adverse cardiovascular events, which can inform clinical practice. These findings should encourage recruitment to, and completion of, ongoing trials.
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Funding:
British Heart Foundation
SARS-CoV-2-encoded small RNAs are able to repress the host expression of SERINC5 to facilitate viral replication
19 páginas, 9 figuras, 1 tablaSerine incorporator protein 5 (SERINC5) is a key innate immunity factor that operates in the cell to restrict the infectivity of certain viruses. Different viruses have developed strategies to antagonize SERINC5 function but, how SERINC5 is controlled during viral infection is poorly understood. Here, we report that SERINC5 levels are reduced in COVID-19 patients during the infection by SARS-CoV-2 and, since no viral protein capable of repressing the expression of SERINC5 has been identified, we hypothesized that SARS-CoV-2 non-coding small viral RNAs (svRNAs) could be responsible for this repression. Two newly identified svRNAs with predicted binding sites in the 3'-untranslated region (3'-UTR) of the SERINC5 gene were characterized and we found that the expression of both svRNAs during the infection was not dependent on the miRNA pathway proteins Dicer and Argonaute-2. By using svRNAs mimic oligonucleotides, we demonstrated that both viral svRNAs can bind the 3'UTR of SERINC5 mRNA, reducing SERINC5 expression in vitro. Moreover, we found that an anti-svRNA treatment to Vero E6 cells before SARS-CoV-2 infection recovered the levels of SERINC5 and reduced the levels of N and S viral proteins. Finally, we showed that SERINC5 positively controls the levels of Mitochondrial Antiviral Signalling (MAVS) protein in Vero E6. These results highlight the therapeutic potential of targeting svRNAs based on their action on key proteins of the innate immune response during SARS-CoV-2 viral infection.This work has been supported by grant CSIC-COV19-106 (202020
E164) from the Spanish National Research Council (CSIC) to FA and
FI, and grant from RTI2018-101291-B-I00 to EE from the Spanish
Ministry of Science and InnovationPeer reviewe
Effects of oral anticoagulation in people with atrial fibrillation after spontaneous intracranial haemorrhage (COCROACH): prospective, individual participant data meta-analysis of randomised trials
Background - The safety and efficacy of oral anticoagulation for prevention of major adverse cardiovascular events in people with atrial fibrillation and spontaneous intracranial haemorrhage are uncertain. We planned to estimate the effects of starting versus avoiding oral anticoagulation in people with spontaneous intracranial haemorrhage and atrial fibrillation.
Methods - In this prospective meta-analysis, we searched bibliographic databases and trial registries using the strategies of a Cochrane systematic review (CD012144) on June 23, 2023. We included clinical trials if they were registered, randomised, and included participants with spontaneous intracranial haemorrhage and atrial fibrillation who were assigned to either start long-term use of any oral anticoagulant agent or avoid oral anticoagulation (ie, placebo, open control, another antithrombotic agent, or another intervention for the prevention of major adverse cardiovascular events). We assessed eligible trials using the Cochrane Risk of Bias tool. We sought data for individual participants who had not opted out of data sharing from chief investigators of completed trials, pending completion of ongoing trials in 2028. The primary outcome was any stroke or cardiovascular death. We used individual participant data to construct a Cox regression model of the time to the first occurrence of outcome events during follow-up in the intention-to-treat dataset supplied by each trial, followed by meta-analysis using a fixed-effect inverse-variance model to generate a pooled estimate of the hazard ratio (HR) with 95% CI. This study is registered with PROSPERO, CRD42021246133.
Findings - We identified four eligible trials; three were restricted to participants with atrial fibrillation and intracranial haemorrhage (SoSTART [NCT03153150], with 203 participants) or intracerebral haemorrhage (APACHE-AF [NCT02565693], with 101 participants, and NASPAF-ICH [NCT02998905], with 30 participants), and one included a subgroup of participants with previous intracranial haemorrhage (ELDERCARE-AF [NCT02801669], with 80 participants). After excluding two participants who opted out of data sharing, we included 412 participants (310 [75%] aged 75 years or older, 249 [60%] with CHA2DS2-VASc score ≤4, and 163 [40%] with CHA2DS2-VASc score >4). The intervention was a direct oral anticoagulant in 209 (99%) of 212 participants who were assigned to start oral anticoagulation, and the comparator was antiplatelet monotherapy in 67 (33%) of 200 participants assigned to avoid oral anticoagulation. The primary outcome of any stroke or cardiovascular death occurred in 29 (14%) of 212 participants who started oral anticoagulation versus 43 (22%) of 200 who avoided oral anticoagulation (pooled HR 0·68 [95% CI 0·42–1·10]; I2=0%). Oral anticoagulation reduced the risk of ischaemic major adverse cardiovascular events (nine [4%] of 212 vs 38 [19%] of 200; pooled HR 0·27 [95% CI 0·13–0·56]; I2=0%). There was no significant increase in haemorrhagic major adverse cardiovascular events (15 [7%] of 212 vs nine [5%] of 200; pooled HR 1·80 [95% CI 0·77–4·21]; I2=0%), death from any cause (38 [18%] of 212 vs 29 [15%] of 200; 1·29 [0·78–2·11]; I2=50%), or death or dependence after 1 year (78 [53%] of 147 vs 74 [51%] of 145; pooled odds ratio 1·12 [95% CI 0·70–1·79]; I2=0%).
Interpretation - For people with atrial fibrillation and intracranial haemorrhage, oral anticoagulation had uncertain effects on the risk of any stroke or cardiovascular death (both overall and in subgroups), haemorrhagic major adverse cardiovascular events, and functional outcome. Oral anticoagulation reduced the risk of ischaemic major adverse cardiovascular events, which can inform clinical practice. These findings should encourage recruitment to, and completion of, ongoing trials.
Funding - British Heart Foundation
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