130 research outputs found
In vitro characterization of the antiviral activity of fucoidan from Cladosiphon okamuranus against Newcastle Disease Virus
Newcastle Disease Virus (NDV) causes a serious infectious disease in birds that results in severe losses
in the worldwide poultry industry. Despite vaccination, NDV outbreaks have increased the necessity of alternative
prevention and control measures. Several recent studies focused on antiviral compounds obtained from natural
resources. Many extracts from marine organisms have been isolated and tested for pharmacological purposes, and
their antiviral activity has been demonstrated in vitro and in vivo. Fucoidan is a sulfated polysaccharide present in the cell wall matrix of brown algae that has been demonstrated to inhibit certain enveloped viruses with low toxicity. This study evaluated the potential antiviral activity and the mechanism of action of fucoidan from Cladosiphon okamuranus against NDV in the Vero cell lin
Magnetic Nanoparticles of Chitosan for Targeted Delivery System of Plasmids to the Lungs
One of the major problems of gene therapy is the efficient, specific, and targeted delivery as well as the safety of the materials used in such systems. The specific targeted delivery of genes to the lung offers the possibility to treat a variety of specific diseases.
We developed chitosan nanoparticles with the plasmid pCEM-Luc, which contains a promoter activated by magnetic field. Nanoparticles of 200–250 nm obtained by ionic gelation with a 99% retention rate were transfected in B16F10 cells and in vivo in the lungs of Balb/c mice by intratracheal administration. We observed that an external magnetic field increased the expression
of the luciferase reporter gene in B16F10 cells transfected with magnetic nanoparticles and inhomogenized lungs of mice which determined differences in levels of expression between different regions of the lungs (apical or distal and left or right). The highest levels of luciferase activity were observed in the apical left region. The magnetic nanoparticles prove an efficient delivery system to in vitro transfection of cells and lung tissue
El papel de la investigacion accion transformadora en la construccion de paz territorial
A pesar de la amplia gama de temas de investigación sobre el conflicto armado y la construcción de paz en Colombia, poco se habla del rol que puede tener la investigación como motor de cambio en esa transición de la guerra a la paz cuando se hace con los propios actores que han formado parte de las dinámicas del conflicto. Este capítulo ofrece esta perspectiva. Para ello nos basamos en la experiencia del proyecto “Escuela, territorio y posconflicto”, trabajando con organizaciones comunitarias del sur del Tolima en el estudio de sus experiencias de construcción de paz en medio del conflicto armado
Paces locales y estrategias transformadoras: más allá de la paz dominante en el sur del Tolima
Legitimidades en disputa: la construcción estatal en escenarios de posconflicto
Esquemáticamente, se puede plantear que gran parte de las investigaciones sobre la paz en Colombia se centran en las dinámicas de victimización y en la lógica del conflicto. En efecto, las series del Centro Nacional de Memoria Histórica parten de esta perspectiva, aun cuando han referido estrategias de resistencia local y mencionan numerosos casos de construcción de paz en medio de la guerra. La paz desde la perspectiva del conflicto, se define como un proceso de desarme, reintegración y reparación. Sin embargo, vienen emergiendo otras lecturas que enfatizan las capacidades de las comunidades locales para soportar, negociar e, incluso, oponerse a los actores armados (Salamanca y Uribe, 2019). En esta línea, la paz se propone como un proceso que implica la transformación de relaciones de poder y de conflictos que emergen una vez se silencian los fusiles (Mac Ginty, 2008, 2010; Roberts, 2011). Esta perspectiva abre espacios para concepciones que superan la llamada estatalización y securitization de la paz. De esto trata este capitul
Effect of Beauveria bassiana-Seed Treatment on Zea mays L. Response against Spodoptera frugiperda
Spodoptera frugiperda is a widely distributed insect pest that causes major economic losses in various crops, particularly maize. On the other hand, Beauveria bassiana is an entomopathogenic fungus that establishes symbiotic associations with many plants and contributes to tolerance against biotic and abiotic stresses. In the present work, in laboratory experiments, the effects of the B. bassiana strain GHA, in addition to a native strain (PTG4), delivered via seed treatment in maize seedlings, were evaluated on S. frugiperda growth, development, and mortality. We inoculated maize seeds with 1 × 106B. bassiana blastospores; then these seeds were germinated and grown to seedlings under growth chamber conditions. Third-instar S. frugiperda larvae were allowed to feed on B. bassiana-treated and -untreated (negative control) seedlings until reaching the sixth instar and transferred to an artificial diet until reaching adult stage. Results showed that larvae feeding on B. bassiana strain PTG4-treated plants prolonged their larval stage. Furthermore, feeding on plants treated with B. bassiana strains yielded fewer S. frugiperda male moths compared with feeding with the untreated control plants. Under field conditions, 1 × 106 (first trial) and 1 × 108 (second trial) of B. bassiana (GHA strain) blastospores were used for corn seed inoculation. In the first field trial, there were a higher number of larvae in the negative control plants compared to those in the plants treated with B. bassiana. No larvae were found in negative control and B. bassiana-treated plants in the second field trial. In conclusion, seed treatment with B. bassiana in maize reduced S. frugiperda infestation of maize plants in field trials. S. frugiperda development was also affected in laboratory trials
El primer año de la pandemia – ¿Qué hemos aprendido del SARS-CoV-2/COVID-19?
Editorial (no Summary)Editorial (Sin resumen
Clonal chromosomal mosaicism and loss of chromosome Y in elderly men increase vulnerability for SARS-CoV-2
The pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2, COVID-19) had an estimated overall case fatality ratio of 1.38% (pre-vaccination), being 53% higher in males and increasing exponentially with age. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, we found 133 cases (1.42%) with detectable clonal mosaicism for chromosome alterations (mCA) and 226 males (5.08%) with acquired loss of chromosome Y (LOY). Individuals with clonal mosaic events (mCA and/or LOY) showed a 54% increase in the risk of COVID-19 lethality. LOY is associated with transcriptomic biomarkers of immune dysfunction, pro-coagulation activity and cardiovascular risk. Interferon-induced genes involved in the initial immune response to SARS-CoV-2 are also down-regulated in LOY. Thus, mCA and LOY underlie at least part of the sex-biased severity and mortality of COVID-19 in aging patients. Given its potential therapeutic and prognostic relevance, evaluation of clonal mosaicism should be implemented as biomarker of COVID-19 severity in elderly people. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, individuals with clonal mosaic events (clonal mosaicism for chromosome alterations and/or loss of chromosome Y) showed an increased risk of COVID-19 lethality
Cabbage and fermented vegetables : From death rate heterogeneity in countries to candidates for mitigation strategies of severe COVID-19
Large differences in COVID-19 death rates exist between countries and between regions of the same country. Some very low death rate countries such as Eastern Asia, Central Europe, or the Balkans have a common feature of eating large quantities of fermented foods. Although biases exist when examining ecological studies, fermented vegetables or cabbage have been associated with low death rates in European countries. SARS-CoV-2 binds to its receptor, the angiotensin-converting enzyme 2 (ACE2). As a result of SARS-CoV-2 binding, ACE2 downregulation enhances the angiotensin II receptor type 1 (AT(1)R) axis associated with oxidative stress. This leads to insulin resistance as well as lung and endothelial damage, two severe outcomes of COVID-19. The nuclear factor (erythroid-derived 2)-like 2 (Nrf2) is the most potent antioxidant in humans and can block in particular the AT(1)R axis. Cabbage contains precursors of sulforaphane, the most active natural activator of Nrf2. Fermented vegetables contain many lactobacilli, which are also potent Nrf2 activators. Three examples are: kimchi in Korea, westernized foods, and the slum paradox. It is proposed that fermented cabbage is a proof-of-concept of dietary manipulations that may enhance Nrf2-associated antioxidant effects, helpful in mitigating COVID-19 severity.Peer reviewe
Nrf2-interacting nutrients and COVID-19 : time for research to develop adaptation strategies
There are large between- and within-country variations in COVID-19 death rates. Some very low death rate settings such as Eastern Asia, Central Europe, the Balkans and Africa have a common feature of eating large quantities of fermented foods whose intake is associated with the activation of the Nrf2 (Nuclear factor (erythroid-derived 2)-like 2) anti-oxidant transcription factor. There are many Nrf2-interacting nutrients (berberine, curcumin, epigallocatechin gallate, genistein, quercetin, resveratrol, sulforaphane) that all act similarly to reduce insulin resistance, endothelial damage, lung injury and cytokine storm. They also act on the same mechanisms (mTOR: Mammalian target of rapamycin, PPAR gamma:Peroxisome proliferator-activated receptor, NF kappa B: Nuclear factor kappa B, ERK: Extracellular signal-regulated kinases and eIF2 alpha:Elongation initiation factor 2 alpha). They may as a result be important in mitigating the severity of COVID-19, acting through the endoplasmic reticulum stress or ACE-Angiotensin-II-AT(1)R axis (AT(1)R) pathway. Many Nrf2-interacting nutrients are also interacting with TRPA1 and/or TRPV1. Interestingly, geographical areas with very low COVID-19 mortality are those with the lowest prevalence of obesity (Sub-Saharan Africa and Asia). It is tempting to propose that Nrf2-interacting foods and nutrients can re-balance insulin resistance and have a significant effect on COVID-19 severity. It is therefore possible that the intake of these foods may restore an optimal natural balance for the Nrf2 pathway and may be of interest in the mitigation of COVID-19 severity
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