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Lopezia racemosa is known as a "mosquito flower or perlilla." It is commonly found in corn crops. In traditional Mexican medicine, this plant is used to treat stomach cancer and urinary tract infections. Likewise, compounds and extracts isolated from plants have shown cytotoxic and anti‐inflammatory effects. The objective of this study was to evaluate the photochemoprotective effect of topical treatment with the methanolic extract of L. racemosa (MELR) as a photochemoprotective agent against the harmful effects of UV irradiation (UVR) on a bacterial model and hairless mice. The MELR components were separated and analyzed via HPLC‐UV‐ESI‐MS. Antioxidant activity was evaluated by the ability of MERL to scavenge DPPH and ABTS free radicals and by its FRAP capacity. The toxicity of MELR was evaluated in keratinocyte cultures. The photoprotective capacity of MELR was assessed through challenge experiments using models with bacteria and hairless CD1 et/et mice; cytokines related to the damage caused by UVR were also measured. In the methanolic extract of L. racemosa, five metabolites were detected and identified: two isomers of quercetin 6‐C glycoside, orientin, quercetin 3‐(6″‐acetylglycoside) and quercetin 3‐(6″‐galloylglycoside) 7‐(2,3‐dihydroxytetrahydro‐2H‐pyran‐4‐yl acetate). MELR exhibited DPPH and ABTS radical scavenging properties, in addition to Fe ion reducing activity. MELR showed a photoprotective effect against UVB radiation‐induced death in Escherichia coli bacteria. At the histological level, topical treatment of CD‐1 et/et mice with MERL reduced the damage caused by UVR. Quantification of interleukins in the blood of mice revealed that the expression of IL‐12 was greater in the control group treated with ultraviolet radiation than in the group protected with MELR. The methanolic extract of L. racemosa has photochemoprotective properties. [ABSTRACT FROM AUTHOR]

Aminoacyl‐tRNA synthetases (aaRSs) establish the genetic code. Each aaRS covalently links a given canonical amino acid to a cognate set of tRNA isoacceptors. Glycyl tRNA aminoacylation is unusual in that it is catalyzed by different aaRSs in different lineages of the Tree of Life. We have investigated the phylogenetic distribution and evolutionary history of bacterial glycyl tRNA synthetase (bacGlyRS). This enzyme is found in early diverging bacterial phyla such as Firmicutes, Acidobacteria, and Proteobacteria, but not in archaea or eukarya. We observe relationships between each of six domains of bacGlyRS and six domains of four different RNA‐modifying proteins. Component domains of bacGlyRS show common ancestry with (i) the catalytic domain of class II tRNA synthetases; (ii) the HD domain of the bacterial RNase Y; (iii) the body and tail domains of the archaeal CCA‐adding enzyme; (iv) the anti‐codon binding domain of the arginyl tRNA synthetase; and (v) a previously unrecognized domain that we call ATL (Ancient tRNA latch). The ATL domain has been found thus far only in bacGlyRS and in the universal alanyl tRNA synthetase (uniAlaRS). Further, the catalytic domain of bacGlyRS is more closely related to the catalytic domain of uniAlaRS than to any other aminoacyl tRNA synthetase. The combined results suggest that the ATL and catalytic domains of these two enzymes are ancestral to bacGlyRS and uniAlaRS, which emerged from common protein ancestors by bricolage, stepwise accumulation of protein domains, before the last universal common ancestor of life. [ABSTRACT FROM AUTHOR]

Cape gooseberry (Physalis peruviana) is Colombia's second most exported fruit, with a market worth 37.8 million USD in 2021. Fusarium oxysporum f sp. physalis (Foph) is arguably the most devastating pathogen causing losses of up to 80%. Managing this disease is challenging due to pathogen resistance or the reduced efficacy of commercial fungicides and the production of resistant structures allowing pathogen survival in the soil for up to 30 years. Thus, new methods of control are necessary. Two cape gooseberry farms (organic vs. conventional) were detected free from Foph in Nariño. We hypothesize that the soil microbiome might have a suppressive effect against vascular wilt, caused by Foph. To test this, farm soils were propagated by adding 10% farm soil and 90% peat soil. Then, peat soil (control) and propagated soils were inoculated with Foph. A decrease of 65%–68% in disease incidence and a 70% in disease severity reduction was observed in seedlings grown in propagated soils compared to peat soil. We then used next‐generation sequencing to study the soil microbiome to understand the possible mechanisms for disease suppression of propagated soils. We conclude that despite the high diversity of soil microbiomes, the relative abundance of some taxa might be a more important indicator of disease suppression than the presence of specific taxa. [ABSTRACT FROM AUTHOR]

Introduction: For many patients with primary immune deficiency (PID), stem‐cell transplantation (SCT) may be life‐saving. Objective: To review our experience of 11 years transplanting children with PID in Mexico. Methods: Chart review of patients who underwent SCT from 2008 to 2018, to describe their diagnoses, time to transplant, conditioning regime, survival rate and outcomes. All patients received post‐transplant cyclophosphamide as graft‐versus‐host‐disease (GVHD) prophylaxis. Results: 19 patients with combined, phagocytic or syndromic PID from 5 states. Twelve of them were male (58%) and 14 survive (79%). Mean age at HSCT was 41.9 months; mean time from diagnosis was 31.2 months. Seven grafts were umbilical cord and 12 haploidentical. The conditioning regime was myeloablative, with five primary graft failures. Two patients had partial and 10 full chimerism. Five patients died within 2 months after transplant. Immune reconstitution was complete in 11 of 19 patients. We found a prevalence of 21% GVHD. Discussion: We describe 19 patients from Mexico with 8 PID diagnoses who underwent allogenic HSCT over a period of 11 years. Survival rate and other outcomes compare well with industrialized countries. We recommend the use of post‐transplant cyclophosphamide to prevent GVHD in scenarios of resource scarcity and a lack of HLA‐identical donors. [ABSTRACT FROM AUTHOR]

The broad distribution of macroparasites and their thriving populations are matters of health and economic concern. Macroparasites cause damage both directly through their feeding habits, which impact host fitness, and indirectly through the transmission of various infectious diseases of relevance to human and domestic animal health and wildlife conservation. Because the impacts of macroparasites on host health and the risk of disease transmission are directly related to their abundance, understanding the drivers of macroparasite burden is of relevance. Various host traits and environmental factors have been associated with differences in macroparasite abundance. In addition to these variables, spatial scale is increasingly incorporated to understand how these drivers vary across space. However, variation in the relative importance of host traits and environmental factors as predictors of abundance at different scales is not well understood. To further clarify the relationship between scale and drivers of macroparasite abundance, we investigated the effects of host traits and environmental factors on flea abundance in rodents of the Chihuahuan Desert in northwestern Mexico on three levels: within a single site, between sampling sites with different vegetation types, and across the region. This partitioning allowed us to compare drivers at both local and regional scales. Fleas provide a natural model to assess the interplay between host and environmental variables across scales because their life cycles alternate between on‐host and off‐host environments and their hosts have varying ranges of distribution. We sampled 1311 fleas from 674 rodent individuals of 14 different species across 40 sampling plots between 2012 and 2013. Using generalized linear mixed models, we found that flea abundance was associated with different combinations of host traits such as size and sex. The specific combination of predictive variables differed across species, while the effects on flea abundance showed context and scale dependency, although this could only be tested at the full level of analysis on the most abundant species, Dipodomys merriami. Sampling season was the only variable consistently significant across scales, reflecting the far‐reaching effects of large‐scale, interannual environmental fluctuations. These results emphasize that integrating spatial scale can strengthen study design for monitoring macroparasite burden. [ABSTRACT FROM AUTHOR]

Background: The disintegrin metalloproteinase 10 (ADAM10) is the main α‐secretase acting in the non‐amyloidogenic processing of APP. Some ADAM10 gene variants (Q170H, R181G) have been associated with higher susceptibility to develop late‐onset AD and have been shown to promote AD‐type changes in mice models. We tested the hypothesis that some ADAM10 rare variants could increase the risk for AD through conferring an earlier age‐related downregulation of a‐secretase activity. Method: ADAM10 gene was sequenced in 103 AD cases (78% with family history) with positive CSF biomarkers, and 96 cognitively preserved nonagenarians. ADAM10 in CSF of the AD cases was analyzed by means of ELISA (total levels) and western blot (segregated by isoforms of 50 kDa, 55 kDa, and 80 kDa) in comparison with controls and non‐AD dementia cases. We examined whether there was an increase of rare gene variants (MAF < 0.01) in the AD group and their potential association with lowers CSF protein levels. Result: Rare variants were found in 15,5% of AD cases (in 23% of early‐onset versus 7,8% in late‐onset, p = 0.058) and in 12,5% of nonagenarians, and several of them were exclusive of the group. However, all were intronic variants except the Q170H change found in three AD cases and one nonagenarian. The SNP rs74016945 (3'UTR), with MAF close to 0.01, was found in 6% of the nonagenarians (OR 0.146, Fisher exact test p = 0.057). ELISA ADAM10 levels were not significantly different comparing AD cases with controls, carriers of rare variants versus non‐carriers, and did not differ consistently according to age at onset or APOE genotype. The three ADAM10 species were also similar in AD cases and controls, and did not differ according to genetic variants or age at onset. Conclusion: Rare ADAM10 exonic variants are uncommon in AD cases and the presence of rare intronic variants (more frequent in early versus late‐onset cases) is not associated with decreased ADAM10 levels in CSF. [ABSTRACT FROM AUTHOR]

Abstract: Oxidative damage to biomolecules is a serious health‐threatening issue, which leads to the development of several diseases. Oxidative conditions are frequently catalyzed by metal ions. In this study, the role of purines in the copper‐catalyzed oxidative stress was investigated using the density functional theory. The obtained results indicate that purines can have a dual behavior, acting as both protectors and promoters of oxidative stress. Their protection role arises from their known radical scavenging activity, as well as their ability to chelate Cu(II) leading to complexes that are—to some extent—harder to reduce than free Cu(II). Conversely, their pro‐oxidant role is a consequence of their reductant behavior, when deprotonated. Thus, the purines’ anions can reduce Cu(II) to Cu(I), making the latter available to be involved in Fenton‐like reactions. Consequently, mixtures of purines and Cu(II), at pHs where the fraction of deprotonated purines is rather significant, would yield •OH radicals. In turn, these very reactive radicals would damage biological targets such as lipids, proteins, and DNA. [ABSTRACT FROM AUTHOR]

Non-marital romantic relationship dissolution is amongst the most stressful life events experienced by young adults. Yet, some individuals experience posttraumatic growth following relationship dissolution. Little is known about the specific and differential contribution of trait-like and event-specific cognitive processing styles to each of these outcomes. A longitudinal design was employed in which trait-like (brooding and reflection) and dissolution-specific (intrusive and deliberate) cognitive processing was examined as predictors of growth (Posttraumatic Growth Inventory) and distress (Breakup Distress Scale) following a recent relationship dissolution. Initially, 148 participants completed measures of trait-like and dissolution-specific cognitive processing, growth, and distress (T1). A subsample completed a seven-month follow-up (T2). Higher frequency of relationship-dissolution intrusive thoughts predicted concurrent distress after accounting for brooding and relationship characteristics. Further, higher brooding and lower reflection predicted higher distress prospectively. Concurrent growth was predicted by both higher brooding and more deliberate relationship-dissolution thoughts. Prospectively, T1 dissolution intrusive thoughts predicted higher T2 deliberate thoughts, and the interaction between these two constructs predicted higher T2 growth. Therefore, deliberately thinking of the dissolution was related to positive psychological outcomes. In contrast, intrusive dissolution cognitions and a tendency for brooding had a mixed (paradoxical) association with psychological adjustment. [ABSTRACT FROM AUTHOR]

The free radical scavenging activity of two Edaravone (EDA) derivatives (C1 and D1) has been studied in aqueous and lipid solutions using the Density Functional Theory. Different mechanisms of reaction have been considered, as well as the acid/base equilibrium in aqueous solution. The studied compounds were found to be rather poor •OOH scavengers in non-polar environments, but better than the parent molecule, EDA, which suggests that the peroxyl scavenging activity of this kind of compounds in lipid media could be increased via structural modifications. In aqueous solution, at physiological pH, D1 is predicted to be a better peroxyl scavenger than C1, and slightly better than its parent molecule, EDA. Their excellent activity, under such conditions, is attributed to the electron transfer from their anionic forms. D1 was found to be among the best peroxyl scavengers known so far, with a rate constant for its reaction with •OOH near the diffusion limit regime (2.3 × 108 M−1s−1). Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The aim of this study is to provide a full comprehensive study of the singular linear parameter-varying (LPV) systems and observer synthesis in a real process. The states and unknown inputs estimation problem for a binary distillation column is solved by using an LPV proportional-integral observer (PI-Observer). A singular LPV model of the process is developed. This model facilitates the design of the PI-Observer for singular LPV systems. The observer proposed is tested using experimental data of a distillation column separating an ethanol-water mixture. The results indicate that the observer is able to accurately reconstruct the product composition dynamics and the unknown inputs of the process. [ABSTRACT FROM AUTHOR]

The free radical scavenging activity of 3-methyl-1-pyridin-2-yl-5-pyrazolone (pyridyl) has been studied in aqueous and lipid solutions, using the density functional theory. Four mechanisms of reaction have been considered: single electron transfer, sequential proton electron transfer (SPET), hydrogen transfer, and radical adduct formation. It was found that the reaction with •OH occur at diffusion-limited rate, which is very similar to that of edaravone, regardless of the polarity of the environment. This indicates that they are both excellent •OH scavengers. Regarding the •OOH scavenging activity of pyridyl, in lipid media it was predicted to be about 15 times higher than that of edaravone. However, in this case they were found to be rather poor •OOH scavengers in lipid media. On the contrary, they are predicted to be excellent •OOH scavengers in aqueous solution. In fact, they were found to be among the best peroxyl radical scavengers in such medium. The rates constants of the •OOH reactions with pyridyl and edaravone, in aqueous solution, were estimated to be 1.1 × 107 and 4.3 × 108 M−1 s−1, respectively. The outstanding scavenging activity of these compounds was attributed to the presence of their anionic forms, which are much more reactive than the neutral species. The reactions with •OOH were found to take place almost exclusively by the SPET mechanism. © 2012 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Summary Bacterial wilt (brown rot) disease of potato caused by Ralstonia solanacearum is one of the most important bacterial diseases and a major constraint on potato production worldwide. Through a comparative genomic analysis between R. solanacearum'race 3 biovar 2' (R3bv2) strains, we identified a 77 kb region in strain UW551 which is specifically absent in the hypoaggressive strain IPO1609. We proved that IPO1609 indeed carries a 77 kb genomic deletion and provide genetic evidence that occurrence of this deletion is responsible for almost complete loss of pathogenicity of this strain. We carried out a functional analysis of this 77 kb region in strain UW551 using a combination of gene deletion and functional complementation approaches which identified the methionine biosynthesis genes metER as having a major contribution to IPO1609 pathogenesis. Deletion of the metER genes significantly impacts pathogenicity of R3bv2 strains but does not lead to methionine auxotrophy nor reduced ability to multiply in planta. In addition, this study indicated that three type III secretion system effectors or a type VI secretion system present within the 77 kb region have no or very minor contribution to pathogenicity. [ABSTRACT FROM AUTHOR]

Oxidative stress mediates chemical damage to DNA yielding a wide variety of products. In this work, the potential capability of melatonin and several of its metabolites to repair directly (chemically) oxidative lesions in DNA was explored. It was found that all the investigated molecules are capable of repairing guanine‐centered radical cations by electron transfer at very high rates, that is, diffusion‐limited. They are also capable of repairing C‐centered radicals in the sugar moiety of 2′‐deoxyguanosine (2dG) by hydrogen atom transfer. Although this was identified as a rather slow process, with rate constants ranging from 1.75 to 5.32 × 102 M−1 s−1, it is expected to be fast enough to prevent propagation of the DNA damage. Melatonin metabolites 6‐hydroxymelatonin (6OHM) and 4‐hydroxymelatonin (4OHM) are also predicted to repair OH adducts in the imidazole ring. In particular, the rate constants corresponding to the repair of 8‐OH‐G adducts were found to be in the order of 104 M−1 s−1 and are assisted by a water molecule. The results presented here strongly suggest that the role of melatonin in preventing DNA damage might be mediated by its capability, combined with that of its metabolites, to directly repair oxidized sites in DNA through different chemical routes. [ABSTRACT FROM AUTHOR]