Search

In order to contribute to the lack of statistical anomaly detection and sensitivity visualization of the response parameters from international seismic codes, this study presents a comparative analysis between multiple Chilean codes for the seismic design of reinforced concrete buildings. The seismic response and its similar implications to the US codes are studied from a model of a reinforced concrete building in the city of Viña del Mar, Chile. The first study case is the NCh433 Of.96 Mod.2009, the second case is the NCh433 Of.96 Mod.2009 + D.S. 117 and 118, and the third case is the NCh433 Of.96 Mod.2009 + D.S. 60 and 61. The results show that the seismic response does not present great differences, but they show noticeable dependencies between multiple parameters within the three study cases. The third case presents the most oversized values of the response parameters, which require a design against a higher base shear. An analysis of the bio-seismic profile is included, which is a procedure commonly used for buildings in Chile, and its indexes are analyzed with statistical models that provide an easy overview of the data structure. Additionally, a pier wall with an opening, and a pier with a T-shaped wall are selected, which present an increase in the amount of reinforcing steel from the first code case to the third, and then to the second code case. [ABSTRACT FROM AUTHOR]

The husk tomato (Physalis spp.) is an exceptional commercial crop for its nutritional and medicinal properties where the whole plant is used. This has led to the search for new micropropagation methods to accelerate plant production in the field. P. angulata and P. chenopodifolia were micropropagated via shoot proliferation of axillary buds and indirect organogenesis. Shoot multiplication was performed on Murashige and Skoog (MS) basal medium supplemented with 2.22, 4.43, or 6.65 μM 6-Benzylaminopurine (BAP) combined with 2.32, 4.64, or 6.96 μM Kinetin (Kin). For P. chenopodifolia, the largest number of new shoots was obtained by adding 4.64 μM Kin (10.47 ± 2.25 shoots per explant); for P. angulata, the best treatment was obtained with a combination of 4.43 μM BAP and 2.32 μM Kin (8.47 ± 2.91 shoots per explant). Indirect organogenesis was performed by placing leaf sections of both Physalis species on MS medium supplemented with 2.22, 4.43, 6.65, or 8.87 BAP combined with 1.13, 2.26, or 3.39 μM 2,4-dichlorophenoxyacetic acid (2,4-D). P. chenopodifolia showed the highest number of new indirect shoots (37.14 ± 3.54) with the addition of 1.13 μM 2,4-D and 6.65 μM BAP; P. angulata had the highest result (22.71 ± 2.5 shoots per explant) with 1.13 μM 2,4-D and 4.43 μM BAP. Stimulation of root induction was obtained in different mediums with auxins 1.07, 2.68, 5.37, or 8.05 μM 1-Naphthaleneacetic acid (NAA) and 1.41, 2.85, 5.70, or 8.55 μM Indoleacetic acid (IAA). The regenerated plantlets resulting from the rooting process were acclimatized and transferred to the greenhouse. The average of shoots per explant in the indirect organogenesis method was higher than the axillary bud culture method. These results could provide an efficient alternative for the micropropagation and conservation of these species with high commercial potential. [ABSTRACT FROM AUTHOR]

Octospora tucumanensis, a new bryophilous ascomycete infecting rhizoids of the pleurocarpous moss Dimerodontium balansae (Fabroniaceae), is described and illustrated based on collections from Argentina. The new species has a unique set of morphological characters and is phylogenetically supported. Morphologically, O. tucumanensis is characterized by the globose to subglobose ascospores ornamented with warts of variable size and shape. Differences from other morphologically similar species of Octospora are discussed. [ABSTRACT FROM AUTHOR]

The urea under high pressure is analyzed from a theoretical point of view using the quantum theory of atoms in molecules and the non-covalent interactions index. For this purpose, four urea crystal structures from X-ray, obtained for different pressures, were used to obtain their electronic structure with the relaxation of hydrogen atom positions using the density functional theory with periodic boundary conditions. From our analysis, the quantum chemistry predictors found N–H ⋯ O hydrogen bonds reported experimentally. Additionally, we found N–H ⋯ N hydrogen bonds, which have not been mentioned or underestimated by experimental arguments. We show that the N–H ⋯ N hydrogen bonds are essential in the description of the urea under high pressure. Furthermore, weak non-covalent interactions, not just hydrogen bonds, become crucial in stabilizing experimental structures under high pressure. This article presents a theoretical description of the molecular interactions involved in urea under high pressure for the first time. [ABSTRACT FROM AUTHOR]

The cortical thickness has been used as a biomarker to assess different cerebral conditions and to detect alterations in the cortical mantle. In this work, we compare methods from the FreeSurfer software, the Computational Anatomy Toolbox (CAT12), a Laplacian approach and a new method here proposed, based on the Euclidean Distance Transform (EDT), and its corresponding computational phantom designed to validate the calculation algorithm. At region of interest (ROI) level, within- and inter-method comparisons were carried out with a test–retest analysis, in a subset comprising 21 healthy subjects taken from the Multi-Modal MRI Reproducibility Resource (MMRR) dataset. From the Minimal Interval Resonance Imaging in Alzheimer's Disease (MIRIAD) data, classification methods were compared in their performance to detect cortical thickness differences between 23 healthy controls (HC) and 45 subjects with Alzheimer's disease (AD). The validation of the proposed EDT-based method showed a more accurate and precise distance measurement as voxel resolution increased. For the within-method comparisons, mean test–retest measures (percentages differences/intraclass correlation/Pearson correlation) were similar for FreeSurfer (1.80%/0.90/0.95), CAT12 (1.91%/0.83/0.91), Laplacian (1.27%/0.89/0.95) and EDT (2.20%/0.88/0.94). Inter-method correlations showed moderate to strong values (R > 0.77) and, in the AD comparison study, all methods were able to detect cortical alterations between groups. Surface- and voxel-based methods have advantages and drawbacks regarding computational demands and measurement precision, while thickness definition was mainly associated to the cortical thickness absolute differences among methods. However, for each method, measurements were reliable, followed similar trends along the cortex and allowed detection of cortical atrophies between HC and patients with AD. [ABSTRACT FROM AUTHOR]

Trace metals have been found in sea turtle blood and tissues and may represent a threat to these endangered species. Essential trace metal (Cu, Zn Cd, Pb, As, and Hg) concentrations were determined in blood of adult female, post-nesting olive ridley turtles Lepidochelys olivacea (n = 35) on Ceuta beach, Sinaloa, Mexico. Essential metals (Zn and Cu) analyzed were found in higher concentrations than toxic metals (Cd and Pb), while As and Hg concentrations were below the limits of detection (0.01 μg g-1). Low Pb concentrations (0.09 μg g-1) were previously observed in sea turtles in the Gulf of California. There were no significant correlations found between curved carapace length (61.00–71.00 ± 2.29) vs metal concentrations (p > 0.05). Cd levels were relatively high when compared to other species and populations of sea turtles worldwide and Cd may represent the greatest risk for sea turtles in the Mexican Pacific. Such concentrations of Cd may pose a further risk to sea turtles through bioaccumulation from the nesting female to offspring which may affect embryo development. [ABSTRACT FROM AUTHOR]

Supramolecular coordination complexes have become of great interest due to their broad spectrum of applicability, mainly in the area of biomedicine. Understanding the role played by the metal center and the weak interactions in the formation and stabilization of these compounds allow us to have a better design of these molecules and therefore a better guide for the examination of novel applications. In this work, we investigate the effect of noncovalent interactions and the presence of metal centers in the stabilization of Tominaga's M12L24 nanoballs. We considered bis(4-pyridyl)-substituted bent frameworks involving two acetylenes spacers as the ligand (L), using –H, –CH3, and a cyanophenyl group as substituents, and two different metal cations: Pd2+ and Ni2+. We found that the bond distance between the metal and the ligand was smaller for the nickel complexes than for the palladium compounds. This is related to the dissociation energies (Ni2+ systems are more stable than Pd2+ compounds). Furthermore, nanoballs with the largest ligand's substituent are significantly more stable than those with the smallest ligand's substituents. Analyzing the frontier states and the Independent Gradient Model isosurfaces, we found that noncovalent interactions contribute to the stabilization of the complexes. Through the charge distribution, we observed that the metal also polarizes the density of the coordination bond. With these results we can conclude that metal centers and noncovalent interactions play an important role in the stabilization of nanoballs. [ABSTRACT FROM AUTHOR]

Vasovagal syncope (VVS) is the most common type of syncope; the lone cardioinhibitory syncope represents only a small group of patients; however, the "cardioinhibitory component" is highly prevalent in reflex syncope and can be severe enough to produce asystole, lasting for a few seconds followed by a recovery to sinus beats. The environment in which syncope occurs can compromise life, and in-depth knowledge of the disease can prevent deaths and guide the appropriate management. The therapeutic cornerstone is general measures (increase water and salt) followed by pharmacologic therapy; for cardioinhibitory syncope, both treatments fail most of the time, and the next therapeutic option is pacemaker implantation. However, although the pacemaker causes a reduction in syncope, recurrence is high, and a one-time, effective, and safe intervention would be ideal. Cardioneuroablation (CNA) therapy has been proposed as a pacemaker alternative with these characteristics. CNA has shown a high reduction or even complete syncope elimination during 3 years of follow-up in some studies. Patients also reported prolonged prodromal periods, which allowed them enough time to abort the syncope. Invasive therapies like CNA require further extensive cohort studies, randomized clinical trials, and more substantial follow-up to evaluate adverse side effects. This review highlights syncope pathophysiology, dividing it into a central theory and a peripheral theory, the diagnosis explaining the head-up tilt test protocols, and treatments like CAN, representing it with figures for a simplified understanding. [ABSTRACT FROM AUTHOR]

The origin, stability, and contribution to the formation of noncovalent interactions, such as hydrogen bonds and π − π stacking, have been already widely discussed. However, there are few discussions about the relevance of these weak interactions in DNA performance. In this work, we seek to shed light on the effect of hydrogen bonds and π − π stacking interactions on the biological behavior of DNA through the description of these intermolecular forces in CpG island–like (GC-rich) chains. Furthermore, we made some comparisons with TATA box–like (TA-rich) chains in order to describe hydrogen bond and π − π stacking interactions as a function of the DNA sequence. For hydrogen bonds, we found that there is not a significant effect related to the number of base pairs. Whereas for π − π stacking interactions, the energy tended to decrease as the number of base pairs increased. We observed anticooperative effects for both hydrogen bonds and π − π stacking interactions. These results are in contrast with those of TATA box–like chains since cooperative and additive effects were found for both hydrogen bonds and π − π stacking, respectively. Based on the chemical hardness and density of states, we can conclude that proteins may interact easier with GC-rich chains. We conclude that regardless of the chain length, a protein could interact more easily with these genomics regions because the π − π stacking energies did not increase as a function of the number of base pairs, making, for the first time, a first approximation of the influence of noncovalent interaction on DNA behavior. We did all this work by means of DFT framework included in the DMol3 code (M06-L/DNP). [ABSTRACT FROM AUTHOR]

In tropical dry forests, a high interspecific variation in the strategies of fruiting phenology has been documented. Therefore, phenological responses may be mediated by influence of environmental variables, functional plant attributes or phylogenetic inertia. During 2 years, we recorded the fruiting phenology of 151 species belonging to 5 different growth forms of a Neotropical dry forest in Mexico. We evaluated the relationships between fruiting phenology, abiotic factors (precipitation, temperature, day-length) and functional attributes (growth form, dispersal syndrome, size and time for fruit development) using phylogenetic least squares models (PGLS). More species had ripe fruits during the dry season (92%) than during rainy months and dispersed their seeds by autochory and endozoochory. We found that fruit development time was positively correlated with fruit size and together the morphological fruit traits (size and dispersal syndrome) showed an important relationship with the growth form, but with a strong phylogenetic signal. Environmental seasonality had a strong influence on fruit ripening time, without a relevant association to the phylogeny of plant species. However, the phenological response to the environment (rainfall and day-length) at the community level was mediated by growth form. In woody species, we documented a high interspecific fruiting variation linked with the different dispersal syndromes. In herbaceous species, fruiting phenology is a trait restricted by the duration of their life cycle by rainfall seasonality, which in turn might have selected some traits (e.g., dry fruit, presence of spines, explosive dehiscence) for maximizing seed dispersal during the dry season. [ABSTRACT FROM AUTHOR]

Background: The prophylactic extraction of third molars is a common practice in dental offices, but divergent opinions are found in the literature regarding the indication of this procedure. The aim of the present study was to determine the prevalence of pathological changes associated with the pericoronal tissue of asymptomatic impacted third molars that could justify prophylactic extraction.Materials and Methods: A cross-sectional observational study was conducted in which 109 pericoronal tissues with no radiographic evidence of pathology were histopathologically analyzed. The specimens were fixed in 10% formalin, embedded in paraffin, stained with hematoxylin and eosin and analyzed individually by two pathologists.Result: The frequency of inflammatory infiltrate in the dental follicle of patients older than 20 years of age was significantly higher than that of younger patients (p = 0.004), demonstrating an association between inflammation in the dental follicle and patient age. The occurrence of squamous metaplasia was also greater in patients older than 20 years (p = 0.042), demonstrating that the prevalence of squamous metaplasia increases with age. A significant association was also found between inflammation and squamous metaplasia (p < 0.001).Conclusion: Pathological changes may be present in the dental follicle of impacted third molars even in the absence of clinical or radiographic signs of disease. [ABSTRACT FROM AUTHOR]

Abstract: Layered double hydroxides (LDH), magnesium-aluminum-carbonates and magnesium-gallium-aluminum-carbonates, were synthesized by sol-gel incorporating during synthesis a part of aluminum as (AlF6)3− blocks in order to incorporate F− as a part of brucite-like layers and not as compensating anions. Structural, textural and surface properties of resulting fluorinated were characterized. Particularly, presence the fluorine as a part of brucite-like layers influenced directly polarity and hydrogen bonding acceptor character at surface of materials. These modifications at surface of LDH greatly changed their catalytic properties. Cyanoethylation reaction between acrylonitrile and methanol was catalyzed by both fluorine-free and fluorinated LDH, pointing out a clear influence of fluorine on the conversion and rate reaction.Graphical Abstract: [ABSTRACT FROM AUTHOR]

Our motivation is to assess the effectiveness of support vector networks (SVN) on the task of detecting deception in texts, as well as to investigate to which degree it is possible to build a domain-independent detector of deception in text using SVN. We experimented with different feature sets for training the SVN: a continuous semantic space model source represented by the latent Dirichlet allocation topics, a word-space model, and dictionary-based features. In this way, a comparison of performance between semantic information and behavioral information is made. We tested several combinations of these features on different datasets designed to identify deception. The datasets used include the DeRev dataset (a corpus of deceptive and truthful opinions about books obtained from Amazon), OpSpam (a corpus of fake and truthful opinions about hotels), and three corpora on controversial topics (abortion, death penalty, and a best friend) on which the subjects were asked to write an idea contrary to what they really believed. We experimented with one-domain setting by training and testing our models separately on each dataset (with fivefold cross-validation), with mixed-domain setting by merging all datasets into one large corpus (again, with fivefold cross-validation), and with cross-domain setting: using one dataset for testing and a concatenation of all other datasets for training. We obtained an average accuracy of 86% in one-domain setting, 75% in mixed-domain setting, and 52 to 64% in cross-domain setting. [ABSTRACT FROM AUTHOR]

Many complex phenomena, from trait selection in biological systems to hierarchy formation in social and economic entities, show signs of competition and heterogeneous performance in the temporal evolution of their components, which may eventually lead to stratified structures such as the worldwide wealth distribution. However, it is still unclear whether the road to hierarchical complexity is determined by the particularities of each phenomena, or if there are generic mechanisms of stratification common to many systems. Human sports and games, with their (varied but simple) rules of competition and measures of performance, serve as an ideal test-bed to look for universal features of hierarchy formation. With this goal in mind, we analyse here the behaviour of performance rankings over time of players and teams for several sports and games, and find statistical regularities in the dynamics of ranks. Specifically the rank diversity, a measure of the number of elements occupying a given rank over a length of time, has the same functional form in sports and games as in languages, another system where competition is determined by the use or disuse of grammatical structures. We use a Gaussian random walk model to reproduce the rank diversity of the studied sports and games. We also discuss the relation between rank diversity and the cumulative rank distribution. Our results support the notion that hierarchical phenomena may be driven by the same underlying mechanisms of rank formation, regardless of the nature of their components. Moreover, such regularities can in principle be used to predict lifetimes of rank occupancy, thus increasing our ability to forecast stratification in the presence of competition. [ABSTRACT FROM AUTHOR]

We present the electrical resistivity model along a profile perpendicular to the Middle America trench in southern Mexico that reveals previously unrecognized tectonic features at upper to mid-crustal depths. Our results support the hypotheses that the upper crust of the Oaxaca terrane is a residual ~20 km thick crust composed by an ~10 km thick faulted crustal upper layer and an ~10 km thick hydrated and/or mineralized layer. Oaxaca basement overthrust the younger Juárez (or Cuicateco) terrane. The electrical resistivity model supports the interpretation of a slab subducting at a low angle below Oaxaca. Uplift in the Oaxaca region appears to be related to fault reactivation induced by low angle subduction. In the Juárez terrane, isostatic forces may contribute to uplift because it is largely uncompensated. In the Sierra Madre del Sur, closer to the coast, uplift is facilitated by slab-dehydration driven buoyancy. Both gravity and resistivity models are consistent with a thinned upper crust in the northeast end of the profile. [ABSTRACT FROM AUTHOR]

Courtship is an innate sexually dimorphic behaviour that can be observed in naive animals without previous learning or experience, suggesting that the neural circuits that mediate this behaviour are developmentally programmed. In Drosophila, courtship involves a complex yet stereotyped array of dimorphic behaviours that are regulated by FruM, a male-specific isoform of the fruitless gene. FruM is expressed in about 2,000 neurons in the fly brain, including three subpopulations of olfactory sensory neurons and projection neurons (PNs). One set of Fru+ olfactory neurons expresses the odorant receptor Or67d and responds to the male-specific pheromone cis-vaccenyl acetate (cVA). These neurons converge on the DA1 glomerulus in the antennal lobe. In males, activation of Or67d+ neurons by cVA inhibits courtship of other males, whereas in females their activation promotes receptivity to other males. These observations pose the question of how a single pheromone acting through the same set of sensory neurons can elicit different behaviours in male and female flies. Anatomical or functional dimorphisms in this neural circuit might be responsible for the dimorphic behaviour. We therefore developed a neural tracing procedure that employs two-photon laser scanning microscopy to activate the photoactivatable green fluorescent protein. Here we show, using this technique, that the projections from the DA1 glomerulus to the protocerebrum are sexually dimorphic. We observe a male-specific axonal arbor in the lateral horn whose elaboration requires the expression of the transcription factor FruM in DA1 projection neurons and other Fru+ cells. The observation that cVA activates a sexually dimorphic circuit in the protocerebrum suggests a mechanism by which a single pheromone can elicit different behaviours in males and in females. [ABSTRACT FROM AUTHOR]

Copyright of Brittonia is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A biophysical model for the interactions between bursting (B) cells and nonbursting (NB) cells in the procerebral lobe of Limax is developed and tested. Phase-sensitivity of the NB cells is exhibited due to the strong inhibition from the rhythmically bursting B cells. Electrical and chemical junctions coupled with a parameter gradient lead to sustained periodic waves in the lobe. Excitatory interactions between the NB cells, which rarely fire, lead to stimulus evoked synchrony in the lobe oscillations. A novel calcium current is suggested to explain the effects of nitric oxide (NO) on the lobe. Gap junctions are shown both experimentally and through simulations to be required for the oscillating field potentials. [ABSTRACT FROM AUTHOR]

Aorto-femoral (A-F) bypass surgery has been performed commonly and safely as an interventional therapy for iliac arterial stenosis or obstruction. Recently, catheter intervention has increasingly replaced this modality. However, no consensus has been reached as to a lesion-specific treatment choice between bypass surgery and catheter intervention. We investigated the patency rates after A-F bypasses according to Trans-Atlantic Inter-Society Consensus (TASC) classifications. This is a multicenter retrospective analysis of 281 patients on whom A-F bypasses were performed between 1991 and 2000. Follow-up extended to a maximum of 10.0 years, with a mean of 3.6 years (± 2.6 years). The overall primary patency rate for all grafts was 94.9% at 5 years. The patency rate for the TASC type-B lesion was lower than that of type-D lesion, with a survival rate at 5 years of 88.0%. The logistic regression analysis revealed that no variables were responsible for the primary patency rate. Renal failure, and peripheral arterial occlusive disease were correlated with a decreased survival rate. We conclude that the late results of A-F bypasses are satisfactory. For the type B lesion, catheter intervention may have a better indication. Chronic renal failure and peripheral arterial occlusive disease may decrease the survival rate. The operative indications should be carefully determined for these cases. [ABSTRACT FROM AUTHOR]

Primary, isolated deep venous incompetence is rare, difficult to diagnose, and can lead to the development of venous stasis ulcers. We herein report a case demonstrating chronic venous stasis ulcers due to primary, isolated deep venous incompetence, which was misdiagnosed as vasculitis ulcers associated with systemic lupus erythematosus (SLE). Although primary, isolated deep venous incompetence is rare, it is important to bear this possibility in mind when a patient presents with leg ulcers. [ABSTRACT FROM AUTHOR]

The ultrastructure of the early spermatogonia in mature testes of the platyfish, Xiphophorus maculatus, was compared to that of oogonia in mature ovaries of X. maculatus and the related X. nigrensis. Both cell types were very similar and, characterized as being large, oval to round cells containing large, central nuclei with prominent nucleoli. Abundant mitochondria with sparse transverse cristae were located at one pole or around the nucleus. Annulate lamellae and electron-dense granular material (nuage) were present. Other organelles were not prominent. A female that had received a testis graft had testicular tissue containing mature spermatozoa within the ovary, indicating that cells were present that could develop along the male line. Special crosses were carried out to obtain all-male embryos of X. maculatus and all-female embryos of X. nigrensis. The ultrastructure of the germ cells in all embryonic gonads was similar to that of the adult cells. These results suggest the presence of sexually undifferentiated germ cells in the adult gonads of both sexes. The support cells investing all of these germ cells were also similar structurally and appeared to be undifferentiated. [ABSTRACT FROM AUTHOR]

Over years of friendly meetings with Professor Aharon Katzir-Katchalsky, many topics of mutual interest were discussed. He was the ideal person to come to with a problem. After being subjected to his critical, analytic mind, most research problems seemed simple, more clearly defined and understandable. His broad biologic and scientific background grew from an apparently insatiable interest in all natural phenomena. He generously shared his knowledge and imparted his wisdom with a share of his own infectious excitement. He was quick to sense the significance of understanding of biological processes to their practical application. For this reason it seems appropriate to relate the progress made in the understanding of cell volume regulation, which had been discussed on several occasions with him, to its possible significance as a factor in disease processes. [ABSTRACT FROM AUTHOR]

A primary abdominal aortic dissection is exceedingly rare, especially in the absence of blunt abdominal trauma. We herein report a case of aortic dissection with aneurysmal dilatation (dissecting aneurysm) of the infrarenal abdominal aorta in a 61-year-old female patient, and discuss the diagnostic and therapeutic management of this rare disorder. [ABSTRACT FROM AUTHOR]

The etiology of femoral artery aneurysms is believed to involve the interaction of a genetic alteration that predisposes to the loss of arterial wall integrity. This is precipitated by local forces such as repeated flexion of the arteries at the hip. We describe herein a case of bilateral femoral and right internal iliac artery aneurysms that developed in a patient with long-standing paraplegia. This could suggest that alterations in the arterial wall caused by stress and kinking during hip flexion may not play a principal role in the pathogenesis of nonspecific femoral artery aneurysms. [ABSTRACT FROM AUTHOR]

Epoxide of oestradiol is one of the main risk factors for the genesis and evolution of breast cancer; hence, in recent years there has been considerable interest in the investigation of new inhibitors capable of reducing its carcinogenic activity. The aim of this article is to study the [2 + 2] cycloaddition reaction of epoxide of oestradiol in different pristine (C76 and D5h-C80) and endohedral metallofullerene (C72@Sc2C2, C76@Sc2 and C80@Sc2) by means of molecular electrostatic potential (MEP) topological analysis. Different from other molecular scalar fields, MEP topology enables to find minima related to lone pairs and π electrons, therefore, this molecular scalar field is appropriate to identify the most reactive sites. In consonance with our results, it was found that C80 was the best candidate to carry out the epoxide of oestradiol cycloaddition since more stable adducts were obtained. Furthermore, it is expected that more than one oestradiol epoxide molecule will be added to C80, forasmuch as C80 reactivity is enhanced once the adduct is formed. The study was carried through DFT framework included in the Gaussian 09 package (MPWB95/6-31G(d,p)). [ABSTRACT FROM AUTHOR]

The phytopathogenic fungus Ustilago maydis causes corn smut by suppressing host plant defenses, including the oxidative burst response. While many studies have investigated how U. maydis responds to oxidative stress during infection, the consequences of heightened resistance to oxidative stress on virulence remain understudied. This study aimed to identify the effects on virulence in U. maydis strains exhibiting enhanced resistance to hydrogen peroxide (H 2 O 2 ).To achieve this, we exposed U. maydis SG200 to 20 escalating H 2 O 2 shocks, resulting in an adapted strain resistant to concentrations as high as 60 mM of H 2 O 2 , a lethal dose for the initial strain. Genetic analysis of the adapted strain revealed five nucleotide substitutions, two minor copy number variants, and a large amplification event on chromosome nine (1-149 kb) encompassing the sole catalase gene. Overexpressing catalase increased resistance to H 2 O 2 ; however, this resistance was lower than that observed in the adapted strain. Additionally, virulence was reduced in both strains with enhanced H 2 O 2 resistance.In summary, enhanced H 2 O 2 resistance, achieved through either continuous exposure to the oxidative agent or through catalase overexpression, decreased virulence. This suggests that the response to the oxidative stress burst in U. maydis is optimal and that increasing the resistance to H 2 O 2 does not translate into increased virulence. These findings illuminate the intricate relationship between oxidative stress resistance and virulence in U. maydis, offering insights into its infection mechanisms., (© 2024. The Author(s).)