2,034 research outputs found
Cardiomyocyte hypertrophy induced by Endonuclease G deficiency requires reactive oxygen radicals accumulation and is inhibitable by the micropeptide humanin
The endonuclease G gene (Endog), which codes for a mitochondrial nuclease, was identified as a determinant of cardiac hypertrophy. How ENDOG controls cardiomyocyte growth is still unknown. Thus, we aimed at finding the link between ENDOG activity and cardiomyocyte growth. Endog deficiency induced reactive oxygen species (ROS) accumulation and abnormal growth in neonatal rodent cardiomyocytes, altering the AKT-GSK3 beta and Class-II histone deacethylases (HDAC) signal transduction pathways. These effects were blocked by ROS scavengers. Lack of ENDOG reduced mitochondrial DNA (mtDNA) replication independently of ROS accumulation. Because mtDNA encodes several subunits of the mitochondrial electron transport chain, whose activity is an important source of cellular ROS, we investigated whether Endog deficiency compromised the expression and activity of the respiratory chain complexes but found no changes in these parameters nor in ATP content. MtDNA also codes for humanin, a micropeptide with possible metabolic functions. Nanomolar concentrations of synthetic humanin restored normal ROS levels and cell size in Endog-deficient cardiomyocytes. These results support the involvement of redox signaling in the control of cardiomyocyte growth by ENDOG and suggest a pathway relating mtDNA content to the regulation of cell growth probably involving humanin, which prevents reactive oxygen radicals accumulation and hypertrophy induced by Endog deficiency.This work was supported by Grant SAF2013-44942R from the Ministerio de Economia y Competitividad (MINECO) to DS, Grant 20153810 from Fundacio La Marato de TV3 to DS, Program ``Redes Tematicas de Investigacion Cooperativa en Salud´´ (RETICS) Grants RD12/0042/0035, RD12/0042/0056 and RD12/0042/0021, Red de Investigacion Cardiovascular (RIC) from the Institute de Salud Carlos-III (ISCIII) to DS, DG-D and JV, Grant 2009SGR-346 from the Agencia de Gestic d'Ajuts Universitaris i de Recerca (AGAUR) from the Government of Catalonia to DS. AB is supported by Fundacio La Marato de TV3 and GB is supported by a predoctoral contract from the Universitat de Lleida.S
GHG Balance of Agricultural Intensification & Bioenergy Production in the Orinoquia Region, Colombia
Energy crop expansion can increase land demand and generate displacement of food crops, which impacts greenhouse gas (GHG) emissions mainly through land-use change (LUC). Increased agricultural productivity could compensate for this. Our study aims to evaluate the regional combined GHG emissions of increasing agricultural yields for food crop and beef production and using the generated surplus land for biomass production to replace fossil fuels in the Orinoquia region of Colombia until 2030. The results show that surplus land for biomass production is obtained only when strong measures are applied to increase agricultural productivity. In the medium and high scenario, a land surplus of 0.6 and 2.4 Mha, respectively, could be generated. Such intensification results in up to 83% emission reduction in Orinoquia’s agricultural sector, largely coming from increasing productivity of cattle production and improving degraded pastures. Biofuel potential from the surplus land is projected at 36 to 368 PJ per year, with a low risk of causing indirect LUC, and results in GHG emission reductions of more than 100% compared to its fossil fuel equivalent. An integrated perspective of the agricultural land use enables sustainable production of both food and bioenergy
American Society of Hematology 2019 guidelines for management of venous thromboembolism : prevention of venous thromboembolism in surgical hospitalized patients
Background: Venous thromboembolism (VTE) is a common source of perioperative morbidity and mortality. Objective: These evidence-based guidelines from the American Society of Hematology (ASH) intend to support decision making about preventing VTE in patients undergoing surgery. Methods: ASH formed a multidisciplinary guideline panel balanced to minimize bias from conflicts of interest. The McMaster University GRADE Centre supported the guideline-development process, including performing systematic reviews. The Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach was used to assess evidence and make recommendations, which were subject to public comment. Results: The panel agreed on 30 recommendations, including for major surgery in general (n = 8), orthopedic surgery (n = 7), major general surgery (n = 3), major neurosurgical procedures (n = 2), urological surgery (n = 4), cardiac surgery and major vascular surgery (n = 2), major trauma (n = 2), and major gynecological surgery (n = 2). Conclusions: For patients undergoing major surgery in general, the panel made conditional recommendations for mechanical prophylaxis over no prophylaxis, for pneumatic compression prophylaxis over graduated compression stockings, and against inferior vena cava filters. In patients undergoing total hip or total knee arthroplasty, conditional recommendations included using either aspirin or anticoagulants, as well as for a direct oral anticoagulant over low-molecular-weight heparin (LMWH). For major general surgery, the panel suggested pharmacological prophylaxis over no prophylaxis, using LMWH or unfractionated heparin. For major neurosurgery, transurethral resection of the prostate, or radical prostatectomy, the panel suggested against pharmacological prophylaxis. For major trauma surgery or major gynecological surgery, the panel suggested pharmacological prophylaxis over no prophylaxis.Peer reviewe
End-to-end tests of the TuMag instrument for the SUNRISE III mission
Ground-based and airborne instrumentation for astronomy IX (2022), Montreal, jul 17-22, 2022.--Proceedings of SPIE - The International Society for Optical Engineering vol. 12184 Article number 121842FSUNRISE III mission is a one-meter aperture telescope onboard a balloon within NASA Long Duration Balloon Program. Three post-focus instruments are used for studying the Sun's dynamics and magnetism, among which the Tunable Magnetograph (TuMag) is a tunable imaging spectropolarimeter.
TuMag is a diffraction-limited imager, a high sensitivity polarimeter (< 10(-3)), and a high-resolution spectrometer (Delta lambda similar to 65 m angstrom). It will be able to study solar magnetic fields at high spatial resolution (similar to 100 km on the solar surface). It will make images of the solar surface magnetic field after measuring the state of polarization of light within three selected spectral lines: the Fe I lines at 525.02 nm and 525.06 nm, and the Mg I b2 line at 517.27 nm. It will be sensitive to the solar vector magnetic fields and line-of-sight velocities, in the photospheric and chromospheric layers. TuMag will be the first solar magnetograph onboard an aerospace platform with the capability of tuning the solar line to be observed.
In this paper the TuMag end-to-end tests carried out during the verification phase are described. These tests are performed to characterize and calibrate the instrument. Specifically, they determine the polarimetric and spectroscopic performances of the instrument as well as the image quality. The availability of a singular facility, an ISO6 clean room with a coelostat on the building roof, allowed the use of solar light during the verification campaign. This was key to a complete instrument verification due to the unique spectroscopic and polarimetric characteristics of solar light.The authors would like to thank Ministerio de Ciencia e Innovacion from the Spanish government for the support of this research via the grant Space Solar Physics RTI2018-096886-B-C5 and "Centro de Excelencia Severo Ochoa" grant SEV-2017-0709.Peer reviewe
Weakly haemolytic variants of Brachyspira hyodysenteriae newly emerged in Europe belong to a distinct subclade with unique genetic properties.
Brachyspira (B.) hyodysenteriae is widespread globally, and can cause mucohaemorrhagic colitis (swine dysentery, SD) with severe economic impact in infected herds. Typical strains of B. hyodysenteriae are strongly haemolytic on blood agar, and the haemolytic activity is believed to contribute to virulence in vivo. However, recently there have been reports of atypical weakly haemolytic isolates of B. hyodysenteriae (whBh). In this study, 34 European whBh and 82 strongly haemolytic isolates were subjected to comparative genomic analysis. A phylogenetic tree constructed using core single nucleotide polymorphisms showed that the whBh formed a distinct sub-clade. All eight genes previously associated with haemolysis in B. hyodysenteriae were present in the whBh. No consistent patterns of amino acid substitutions for all whBh were found in these genes. In contrast, a genome region containing six coding sequences (CDSs) had consistent nucleotide sequence differences between strongly and whBh isolates. Two CDSs were predicted to encode ABC transporter proteins, and a TolC family protein, which may have a role in the export of haemolysins from B. hyodysenteriae. Another difference in this region was the presence of three CDSs in whBh that are pseudogenes in strongly haemolytic isolates. One of the intact CDSs from whBh encoded a predicted PadR-like transcriptional repressor that may play a role in repression of haemolysis functions. In summary, a sub-clade of whBh isolates has emerged in Europe, and several genomic differences, that potentially explain the weakly haemolytic phenotype, were identified. These markers may provide targets for discriminatory molecular tests needed in SD surveillance
Rapid reviews of medical tests used many similar methods to systematic reviews but key items were rarely reported: a scoping review.
BACKGROUND
Rapid reviews provide an efficient alternative to standard systematic reviews in response to a high priority or urgent need. Although rapid reviews of interventions have been extensively evaluated, little is known about the characteristics of rapid reviews of diagnostic evidence.
STUDY DESIGN AND SETTING
We performed a scoping review for rapid reviews of medical tests published from 2013 to 2018. We extracted information on review characteristics and methods used to assess the evidence.
RESULTS
We identified 191 rapid reviews. All reviews were developed within a short time (less than 12 months) and were relatively concise (less than 10 pages). The reviews involved multiple index tests (44%), multiple outcomes (88%), and several test applications (29%). Well-known methodological tailoring strategies were infrequently used. Although reporting of several key features was limited, we found that, in general, rapid reviews have similar characteristics to broader knowledge syntheses.
CONCLUSION
Our scoping review is the first to describe the characteristics and methods of rapid reviews of diagnostic evidence. Future research should identify the most appropriate methods for performing rapid reviews of medical tests. Standards for reporting of rapid reviews are needed
The GHG emissions and economic performance of the Colombian palm oil sector; current status and long-term perspectives
Increasing oil palm plantations, both for obtaining crude palm oil (CPO) and for the production of biobased products, have generated growing concern about the impact of greenhouse gas (GHG) emissions on the environment. Colombia has the potential to produce sustainable biobased products from oil palm. Nevertheless, national GHG emissions have not yet been reported by this sector. Achieving the collection of the total primary data from the oil palm sector, in Colombia, entails a tremendous challenge. Notwithstanding, for this study, the data collection of 70% of the production of fresh fruit bunches (FFB) was achieved. Therefore, current situation of CPO production in Colombia is analyzed, including 1) GHG emissions calculation, 2) net energy ratio (NER), and 3) economic performance. Moreover, the analysis includes two future scenarios, where the CPO production chain is optimized to reduce GHG emissions. Future scenario A produces biodiesel (BD), biogas, cogeneration, and compost; while future scenario B produces BD, biogas, cogeneration, and pellets. The methodology, for all the scenarios, includes life-cycle assessment and economic analysis evaluation. The results show a significant potential for improving the current palm oil production, including a 55% reduction in GHG emissions. The impact of land-use change must be mitigated to reduce GHG emissions. Therefore, a sustainable oil palm expansion should be in areas with low carbon stock or areas suitable/available to the crop (e.g., cropland, pastureland). Avoiding the deforestation of natural forests is required. Besides, crop yield should be increased to minimize the land use, using biomass to produce biobased products, and capture biogas to reduce methane emissions. In the biodiesel production life-cycle, the NER analysis shows the fossil energy consumed is lower than the renewable energy produced. Regarding the economic performance, it shows that in an optimized production chain, the capital expenditure and operational expenditure will decrease by approximately 20%
The Astropy Problem
The Astropy Project (http://astropy.org) is, in its own words, "a community
effort to develop a single core package for Astronomy in Python and foster
interoperability between Python astronomy packages." For five years this
project has been managed, written, and operated as a grassroots,
self-organized, almost entirely volunteer effort while the software is used by
the majority of the astronomical community. Despite this, the project has
always been and remains to this day effectively unfunded. Further, contributors
receive little or no formal recognition for creating and supporting what is now
critical software. This paper explores the problem in detail, outlines possible
solutions to correct this, and presents a few suggestions on how to address the
sustainability of general purpose astronomical software
Recommended from our members
Anesthetic action on the transmission delay between cortex and thalamus explains the beta-buzz observed under propofol anesthesia
In recent years, more and more surgeries under general anesthesia have been performed with the assistance of electroencephalogram (EEG) monitors. An increase in anesthetic concentration leads to characteristic changes in the power spectra of the EEG. Although tracking the anesthetic-induced changes in EEG rhythms can be employed to estimate the depth of anesthesia, their precise underlying mechanisms are still unknown. A prominent feature in the EEG of some patients is the emergence of a strong power peak in the β–frequency band, which moves to the α–frequency band while increasing the anesthetic concentration. This feature is called the beta-buzz. In the present study, we use a thalamo-cortical neural population feedback model to reproduce observed characteristic features in frontal EEG power obtained experimentally during propofol general anesthesia, such as this beta-buzz. First, we find that the spectral power peak in the α– and δ–frequency ranges depend on the decay rate constant of excitatory and inhibitory synapses, but the anesthetic action on synapses does not explain the beta-buzz. Moreover, considering the action of propofol on the transmission delay between cortex and thalamus, the model reveals that the beta-buzz may result from a prolongation of the transmission delay by increasing propofol concentration. A corresponding relationship between transmission delay and anesthetic blood concentration is derived. Finally, an analytical stability study demonstrates that increasing propofol concentration moves the systems resting state towards its stability threshold
Comparison of seven prognostic tools to identify low-risk pulmonary embolism in patients aged <50 years
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