Pedalitin from Isodon japonica, an inactivation of soybean lipoxygenase-1

Pedalitin, isolated from the aerial part of Rabdosia japonica (Labiatae), inhibited soybean lipoxygenase-1 (EC 1.13.11.12, Type I) with an IC50 of 152.5 M. The progress curves for an enzyme reaction, pedalitin inactivate the lipoxygenase-1 in a time dependent, irreversible manner, exhibiting kinetics with a kinact/KI of 59.6 ± 10 mM-1min-1. In the pseudoperoxidase activity, pedalitin is very slowly oxidized by the soybean lipoxygenase-1 catalyzed decomposition of lipid hydroperoxides

Thickness dependence study of current-driven ferromagnetic resonance in Y3Fe5O12/heavy metal bilayers

We use ferromagnetic resonance to study the current-induced torques in YIG/heavy metal bilayers. YIG samples with thickness varying from 14.8 nm to 80 nm, with the Pt or Ta thin film on top, are measured by applying a microwave current into the heavy metals and measuring the longitudinal DC voltage generated by both spin rectification and spin pumping. From a symmetry analysis of the FMR lineshape and its dependence on YIG thickness, we deduce that the Oersted field dominates over spin-transfer torque in driving magnetization dynamics

Spatio-temporal dynamics of dengue 2009 outbreak in Córdoba city, Argentina.

During 2009 the biggest dengue epidemic to date occurred in Argentina, affecting almost half the country. We studied the spatio-temporal dynamics of the outbreak in the second most populated city of the country, Córdoba city. Confirmed cases and the results of an Aedes aegypti monitoring during the outbreak were geolocated. The imported cases began in January, and the autochthonous in March. Thirty-three percent of the 130 confirmed cases were imported, and occurred mainly at the center of the city. The autochthonous cases were more frequent in the outskirts, specially in the NE and SE. Aedes aegypti infestation showed no difference between neighborhoods with or without autochthonous cases, neither between neighborhoods with autochthonous vs. imported cases. The neighborhoods with imported cases presented higher population densities. The majority of autochthonous cases occurred at ages between 25 and 44 years old. Cases formed a spatio-temporal cluster of up to 20 days and 12 km. According to a athematical model that estimates the required number of days needed for transmission according to daily temperature, the number of cases begun to fall when more than 15.5 days were needed. This may be a coarse estimation of mean mosquito survival in the area, provided that the study area is close to the global distribution limit of the vector, and that cases prevalence was very low.Fil: Estallo, Elizabet Lilia. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Centro de Investigaciones Entomológicas de Córdoba; ArgentinaFil: Carbajo, Anibal Eduardo. Universidad Nacional de San Martín. Instituto de Investigación e Ingeniería Ambiental; ArgentinaFil: Grech, Marta Gladys. Universidad Nacional de la Patagonia "San Juan Bosco". Facultad de Ciencias Naturales - Sede Esquel. Departamento de Biología. Laboratorio de Investigaciones en Ecología y Sistemática Animal; ArgentinaFil: Frias Cespedes, M.. Ministerio de Salud de la Provincia de Córdoba; ArgentinaFil: Lopez, L.. Ministerio de Salud de la Provincia de Córdoba; ArgentinaFil: Lanfri, M. A.. Comision Nacional de Actividades Espaciales; ArgentinaFil: Ludueña Almeida, Francisco F.. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Centro de Investigaciones Entomológicas de Córdoba; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Córdoba. Instituto de Investigaciones Biológicas y Tecnológicas; ArgentinaFil: Almiron, Walter Ricardo. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Centro de Investigaciones Entomológicas de Córdoba; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Córdoba. Instituto de Investigaciones Biológicas y Tecnológicas; Argentin

Mast Cell Chymase/Mcpt4 Suppresses the Host Immune Response to Plasmodium yoelii, Limits Malaria-Associated Disruption of Intestinal Barrier Integrity and Reduces Parasite Transmission to Anopheles stephensi

An increase in mast cells (MCs) and MCs mediators has been observed in malaria-associated bacteremia, however, the role of these granulocytes in malarial immunity is poorly understood. Herein, we studied the role of mouse MC protease (Mcpt) 4, an ortholog of human MC chymase, in malaria-induced bacteremia using Mcpt4 knockout (Mcpt4(-/-)) mice and Mcpt4(+/+) C57BL/6J controls, and the non-lethal mouse parasite Plasmodium yoelii yoelii 17XNL. Significantly lower parasitemia was observed in Mcpt4(-/-) mice compared with Mcpt4(+/+) controls by day 10 post infection (PI). Although bacterial 16S DNA levels in blood were not different between groups, increased intestinal permeability to FITC-dextran and altered ileal adherens junction E-cadherin were observed in Mcpt4(-/-) mice. Relative to infected Mcpt4(+/+) mice, ileal MC accumulation in Mcpt4(-/-) mice occurred two days earlier and IgE levels were higher by days 8-10 PI. Increased levels of circulating myeloperoxidase were observed at 6 and 10 days PI in Mcpt4(+/+) but not Mcpt4(-/-) mice, affirming a role for neutrophil activation that was not predictive of parasitemia or bacterial 16S copies in blood. In contrast, early increased plasma levels of TNF-alpha, IL-12p40 and IL-3 were observed in Mcpt4(-/-) mice, while levels of IL-2, IL-10 and MIP1 beta (CCL4) were increased over the same period in Mcpt4(+/+) mice, suggesting that the host response to infection was skewed toward a type-1 immune response in Mcpt4(-/-) mice and type-2 response in Mcpt4(+/+) mice. Spearman analysis revealed an early (day 4 PI) correlation of Mcpt4(-/-) parasitemia with TNF-alpha and IFN-gamma, inflammatory cytokines known for their roles in pathogen clearance, a pattern that was observed in Mcpt4(+/+) mice much later (day 10 PI). Transmission success of P. y. yoelii 17XNL to Anopheles stephensi was significantly higher from infected Mcpt4(-/-) mice compared with infected Mcpt4(+/+) mice, suggesting that Mcpt4 also impacts transmissibility of sexual stage parasites. Together, these results suggest that early MCs activation and release of Mcpt4 suppresses the host immune response to P. y. yoelii 17XNL, perhaps via degradation of TNF-alpha and promotion of a type-2 immune response that concordantly protects epithelial barrier integrity, while limiting the systemic response to bacteremia and parasite transmissibility

Observation of a molecular muonium polaron and its application to probing magnetic and electronic states

We thank the Engineering and Physical Sciences Research Council (EPSRC UK) for support via Grants No. EP/M000923/1, No. EP/K036408/1, No. EP/I004483/1, No. EP/S031081/1, and No. EP/S030263/1. L.L., S.S., D.J. and G.T. acknowledge also support from STFC-ISIS Neutron and Muon Source and Ada Lovelace Centre at STFC-SCD. We acknowledge use of the ARCHER (via the U.K. Car–Parrinello Consortium, EP/P022618/1 and EP/P022189/2), U.K. Materials and Molecular Modelling Hub (EP/P020194/1), and STFC Scientific Computing Department's SCARF HCP facilities. We acknowledge support from the Henry Royce Institute. This work was also supported financially through the EPSRC Grant Nos. EP/ P022464/1, and EP/R00661X/1.Muonium is a combination of first- and second-generation matter formed by the electrostatic interaction between an electron and an antimuon (μ+). Although a well-known physical system, their ability to form collective excitations in molecules had not been observed. Here, we give evidence for the detection of a muonium state that propagates in a molecular semiconductor lattice via thermally activated dynamics: a muonium polaron. By measuring the temperature dependence of the depolarization of the muonium state in C60, we observe a thermal narrowing of the hyperfine distribution that we attribute to the dynamics of the muonium between molecular sites. As a result of the time scale for muonium decay, the energies involved, charge and spin selectivity, this quasiparticle is a widely applicable experimental tool. It is an excellent probe of emerging electronic, dynamic, and magnetic states at interfaces and in low dimensional systems, where direct spatial probing is an experimental challenge owing to the buried interface, nanoscale elements providing the functionality localization and small magnitude of the effects.Publisher PDFPeer reviewe

Social Support and Substance Use as Moderators of the Relationship Between Depressive Symptoms and Suicidal Ideation in Adolescents

Indexación: Scopus.Literature reports that depressive symptoms may precede suicidal ideation. Several studies have identified social support and substance use as moderators of this relationship. However, no study has evaluated these variables together by testing how substance use can affect the moderating effect of social support in this relationship. The purpose of this article is to individually evaluate dimensions of social support (friends, family, significant others, and school) and substance use (alcohol, marijuana, and other illicit drugs), as moderators of the relationship between depressive symptoms and suicidal ideation, as well as analyze the moderating role of substance use in the moderation exerted by social support in this relationship. This study, quantitative and cross-sectional, considered 775 adolescents [Average age = 15.48 (SD = 0.96), 45.9% women], from 20 randomly selected schools in Santiago de Chile. Simple moderation models were used to analyze possible moderators separately, and double moderation models were used to analyze the moderating role of substance use in the moderating effect of social support. The results show that the four dimensions of social support moderate the relationship between depressive symptomatology and suicidal ideation, showing the strongest interaction in the case of family support, followed by support of a significant person, support at school, and support of friends, in that order. On the other hand, alcohol was the only drug that moderated the relationship in question. In addition, the results show that the use of alcohol limits the moderating effect of social support in the fields of family, significant person, and school support, but not in the case of support of friends. The use of marijuana and other illicit drugs did not affect the moderating effects of social support for any of the areas evaluated. The results are discussed according to the different roles that alcohol use can play in adolescence, and how these, together with perceived social support, are related to the emergence of suicidal ideation from depressive symptoms. © Copyright © 2020 Rubio, Oyanedel, Cancino, Benavente, Céspedes, Zisis and Páez.https://www.frontiersin.org/articles/10.3389/fpsyg.2020.539165/ful

Effective theories of single field inflation when heavy fields matter

We compute the low energy effective field theory (EFT) expansion for single-field inflationary models that descend from a parent theory containing multiple other scalar fields. By assuming that all other degrees of freedom in the parent theory are sufficiently massive relative to the inflaton, it is possible to derive an EFT valid to arbitrary order in perturbations, provided certain generalized adiabaticity conditions are respected. These conditions permit a consistent low energy EFT description even when the inflaton deviates off its adiabatic minimum along its slowly rolling trajectory. By generalizing the formalism that identifies the adiabatic mode with the Goldstone boson of this spontaneously broken time translational symmetry prior to the integration of the heavy fields, we show that this invariance of the parent theory dictates the entire non-perturbative structure of the descendent EFT. The couplings of this theory can be written entirely in terms of the reduced speed of sound of adiabatic perturbations. The resulting operator expansion is distinguishable from that of other scenarios, such as standard single inflation or DBI inflation. In particular, we re-derive how certain operators can become transiently strongly coupled along the inflaton trajectory, consistent with slow-roll and the validity of the EFT expansion, imprinting features in the primordial power spectrum, and we deduce the relevant cubic operators that imply distinct signatures in the primordial bispectrum which may soon be constrained by observations.Comment: (v1) 25 pages, 1 figure; (v2) references added and typos corrected, to appear in Journal of High Energy Physic

Synthetic Lethality of Chk1 Inhibition Combined with p53 and/or p21 Loss During a DNA Damage Response in Normal and Tumor Cells

Cell cycle checkpoints ensure genome integrity and are frequently compromised in human cancers. A therapeutic strategy being explored takes advantage of checkpoint defects in p53-deficient tumors in order to sensitize them to DNA-damaging agents by eliminating Chk1-mediated checkpoint responses. Using mouse models, we demonstrated that p21 is a key determinant of how cells respond to the combination of DNA damage and Chk1 inhibition (combination therapy) in normal cells as well as in tumors. Loss of p21 sensitized normal cells to the combination therapy much more than did p53 loss and the enhanced lethality was partially blocked by CDK inhibition. In addition, basal pools of p21 (p53 independent) provided p53 null cells with protection from the combination therapy. Our results uncover a novel p53-independent function for p21 in protecting cells from the lethal effects of DNA damage followed by Chk1 inhibition. As p21 levels are low in a significant fraction of colorectal tumors, they are predicted to be particularly sensitive to the combination therapy. Results reported in this study support this prediction

Change in longitudinal trends in sleep quality and duration following breast cancer diagnosis: results from the Women's Health Initiative

Breast cancer survivors frequently report sleep problems, but little research has studied sleep patterns longitudinally. We examined trends in sleep quality and duration up to 15 years before and 20 years after a diagnosis of breast cancer, over time among postmenopausal women participating in the Women's Health Initiative (WHI). We included 12,098 participants who developed invasive breast cancer after study enrollment. A linear mixed-effects model was used to determine whether the time trend in sleep quality, as measured by the WHI Insomnia Rating Scale (WHIIRS), a measure of perceived insomnia symptoms from the past 4 weeks, changed following a cancer diagnosis. To examine sleep duration, we fit a logistic regression model with random effects for both short (<6 h) and long (≥9 h) sleep. In addition, we studied the association between depressive symptoms and changes in WHIIRS and sleep duration. There was a significantly slower increase in the trend of WHIIRS after diagnosis (β = 0.06; p = 0.03), but there were non-significant increases in the trend of the probability of short or long sleep after diagnosis. The probability of depressive symptoms significantly decreased, though the decrease was more pronounced after diagnosis (p < 0.01). Trends in WHIIRS worsened at a relatively slower rate following diagnosis and lower depression rates may explain the slower worsening in WHIIRS. Our findings suggest that over a long period of time, breast cancer diagnosis does not adversely affect sleep quality and duration in postmenopausal women compared to sleep pre-diagnosis, yet both sleep quality and duration continue to worsen over time.WHI - National Heart, Lung, and Blood Institute, National Institutes of Health, US Department of Health and Human Services [HHSN268201600018C, HHSN268201600001C, HHSN268201600002C, HHSN268201600003C, HHSN268201600004C]; Ohio State University Susan G Komen Graduate Trainee Program [GTDR15334082]Open access journalThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]