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1.
Ecol Evol ; 14(7): e11496, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38983703

RESUMO

Differential expression of genes is key to mediating developmental and stress-related plant responses. Here, we addressed the regulation of plant metabolic responses to biotic stress and the developmental variation of defense-related genes in four species of the genus Datura with variable patterns of metabolite accumulation and development. We combine transcriptome profiling with phylogenomic techniques to analyze gene expression and coexpression in plants subjected to damage by a specialist folivore insect. We found (1) common overall gene expression in species of similar chemical profiles, (2) species-specific responses of proteins involved in specialized metabolism, characterized by constant levels of gene expression coupled with transcriptional rearrangement, and (3) induction of transcriptional rearrangement of major terpene and tropane alkaloid genes upon herbivory. Our results indicate differential modulation of terpene and tropane metabolism linked to jasmonate signaling and specific transcription factors to regulate developmental variation and stress programs, and suggest plastic adaptive responses to cope with herbivory. The transcriptional profiles of specialized metabolism shown here reveal complex genetic control of plant metabolism and contribute to understanding the molecular basis of adaptations and the physiological variation of significant ecological traits.

2.
Healthcare (Basel) ; 12(6)2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38540647

RESUMO

This study explores the integration of large language models (LLMs), like ChatGPT, to improve attention deficit hyperactivity disorder (ADHD) treatments. Utilizing the Delphi method for its systematic forecasting capabilities, we gathered a panel of child ADHD therapy experts. These experts interacted with our custom ChatGPT through a specialized interface, thus engaging in simulated therapy scenarios with behavioral prompts and commands. Using empirical tests and expert feedback, we aimed to rigorously evaluate ChatGPT's effectiveness in therapy settings to integrate AI into healthcare responsibly. We sought to ensure that AI contributes positively and ethically to therapy and patient care, thus filling a gap in ADHD treatment methods. Findings show ChatGPT's empathy, adaptability, and communication strengths, thereby highlighting its potential to significantly improve ADHD care. The study points to ChatGPT's capacity to transform therapy practices through personalized and responsive patient care. However, it also notes the need for enhancements in privacy, cultural sensitivity, and interpreting nonverbal cues for ChatGPT's effective healthcare integration. Our research advocates for merging technological innovation with a comprehensive understanding of patient needs and ethical considerations, thereby aiming to pioneer a new era of AI-assisted therapy. We emphasize the ongoing refinement of AI tools like ChatGPT to meet ADHD therapy and patient care requirements more effectively.

4.
Development ; 151(2)2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38276966

RESUMO

Cell shape is a powerful readout of cell state, fate and function. We describe a custom workflow to perform semi-automated, 3D cell and nucleus segmentation, and spherical harmonics and principal components analysis to distill cell and nuclear shape variation into discrete biologically meaningful parameters. We apply these methods to analyze shape in the neuromast cells of the zebrafish lateral line system, finding that shapes vary with cell location and identity. The distinction between hair cells and support cells accounted for much of the variation, which allowed us to train classifiers to predict cell identity from shape features. Using transgenic markers for support cell subpopulations, we found that subtypes had different shapes from each other. To investigate how loss of a neuromast cell type altered cell shape distributions, we examined atoh1a mutants that lack hair cells. We found that mutant neuromasts lacked the cell shape phenotype associated with hair cells, but did not exhibit a mutant-specific cell shape. Our results demonstrate the utility of using 3D cell shape features to characterize, compare and classify cells in a living developing organism.


Assuntos
Sistema da Linha Lateral , Peixe-Zebra , Animais , Peixe-Zebra/genética , Forma Celular , Animais Geneticamente Modificados , Células Ciliadas Auditivas/fisiologia
5.
Plants (Basel) ; 13(1)2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38202439

RESUMO

When colonizing new ranges, plant populations may benefit from the absence of the checks imposed by the enemies, herbivores, and pathogens that regulated their numbers in their original range. Therefore, rates of plant damage or infestation by natural enemies are expected to be lower in the new range. Exposing both non-native and native plant populations in the native range, where native herbivores are present, can be used to test whether resistance mechanisms have diverged between populations. Datura stramonium is native to the Americas but widely distributed in Spain, where populations show lower herbivore damage than populations in the native range. We established experiments in two localities in the native range (Mexico), exposing two native and two non-native D. stramonium populations to natural herbivores. Plant performance differed between the localities, as did the abundance of the main specialist herbivore, Lema daturaphila. In Teotihuacán, where L. daturaphila is common, native plants had significantly more adult beetles and herbivore damage than non-native plants. The degree of infestation by the specialist seed predator Trichobaris soror differed among populations and between sites, but the native Ticumán population always had the lowest level of infestation. The Ticumán population also had the highest concentration of the alkaloid scopolamine. Scopolamine was negatively related to the number of eggs deposited by L. daturaphila in Teotihuacán. There was among-family variation in herbivore damage (resistance), alkaloid content (scopolamine), and infestation by L. daturaphila and T. soror, indicating genetic variation and potential for further evolution. Although native and non-native D. stramonium populations have not yet diverged in plant resistance/constitutive defense, the differences between ranges (and the two experimental sites) in the type and abundance of herbivores suggest that further research is needed on the role of resource availability and adaptive plasticity, specialized metabolites (induced, constitutive), and the relationship between genealogical origin and plant defense in both ranges.

6.
G3 (Bethesda) ; 14(2)2024 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-38113048

RESUMO

Plant resistance refers to the heritable ability of plants to reduce damage caused by natural enemies, such as herbivores and pathogens, either through constitutive or induced traits like chemical compounds or trichomes. However, the genetic architecture-the number and genome location of genes that affect plant defense and the magnitude of their effects-of plant resistance to arthropod herbivores in natural populations remains poorly understood. In this study, we aimed to unveil the genetic architecture of plant resistance to insect herbivores in the annual herb Datura stramonium (Solanaceae) through quantitative trait loci mapping. We achieved this by assembling the species' genome and constructing a linkage map using an F2 progeny transplanted into natural habitats. Furthermore, we conducted differential gene expression analysis between undamaged and damaged plants caused by the primary folivore, Lema daturaphila larvae. Our genome assembly resulted in 6,109 scaffolds distributed across 12 haploid chromosomes. A single quantitative trait loci region on chromosome 3 was associated with plant resistance, spanning 0 to 5.17 cM. The explained variance by the quantitative trait loci was 8.44%. Our findings imply that the resistance mechanisms of D. stramonium are shaped by the complex interplay of multiple genes with minor effects. Protein-protein interaction networks involving genes within the quantitative trait loci region and overexpressed genes uncovered the key role of receptor-like cytoplasmic kinases in signaling and regulating tropane alkaloids and terpenoids, which serve as powerful chemical defenses against D. stramonium herbivores. The data generated in our study constitute important resources for delving into the evolution and ecology of secondary compounds mediating plant-insect interactions.


Assuntos
Datura stramonium , Animais , Datura stramonium/genética , Herbivoria , Insetos , Ecologia , Plantas , Cromossomos
7.
Ecol Evol ; 13(12): e10794, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38077505

RESUMO

The expression of plant resistance traits against arthropod herbivores often comes with costs to other essential plant functions such as growth and fitness. These trade-offs are shaped by the allocation of limited resources. However, plants might also possess the capability to allocate resources to both resistance and growth, thereby ensuring their survival when under herbivore attacks. Additionally, the extent of damage caused by herbivores could vary across different years or seasons, subsequently impacting plant performance. In this study, we aimed to investigate how the annual variations in herbivore abundance and damage levels affect plant performance. We generated F2 progeny through a cross between two populations of the annual herb Datura stramonium (Solanaceae). These populations are known to have differing levels of chemical defense and herbivory. These F2 plants were cultivated in a common natural environment for two consecutive years (2017 and 2018). Our findings reveal that plants with higher resistance, attained higher seed production but this trend was evident only during 2018. This relationship coincided with a five-fold increase in the abundance of Lema daturaphila (Chrysomelidae) larvae in 2018. Indeed, the plants experienced a 13-fold increase in damage during this second year of study. Furthermore, our results indicated that there was no trade-off between resistance, growth, and fitness in either of the 2 years. In contrast, during 2018, when plants faced stronger herbivore pressure, they allocated all available nutritional resources to enhance both resistance and growth. Our study highlights how the selection for plant resistance is dependent upon the inter-annual variation in herbivore abundance.

8.
An Acad Bras Cienc ; 95(4): e20200042, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38088700

RESUMO

The corn cropping system can influence the natural enemy identity and the number of Spodoptera frugiperda J.E. Smith, 1797 (Lepidoptera: Noctuidae) individuals infesting the cartridge, ear and stem of this plant. The objectives were to identify the S. frugiperda natural enemies and differences in the number of individuals infesting the cartridge, ear and stem of corn plants under conventional and organic cropping systems, in Brazil after an initial collection of adult males through semiochemical traps. We also evaluated key morphometrical parameters of the larva and factors contributing with the viability of S. frugiperda. A total of 16 and 136 adult males was trapped, and 1,124 and 1,112 larvae was recovered from conventional and organic systems with 4.7 and 6.7% of them parasitized by dipteran and hymenopteran, respectively. Most of the parasitoids recovered had occurrence in both cropping systems, except Cremastinae and Ophion flavidus Brullé, 1846 (Hymenoptera: Ichneumonidae), which were recorded only in organic and Campoletis sp. (Hymenoptera: Ichneumonidae) only in conventional corns. The number of parasitoids recovered was similar in corn plant samples between both cropping systems. A total of 152 and 31 larvae was recovered from corn ears under conventional and organic systems, respectively. Doru luteipes (Scudder, 1876) (Dermaptera: Forficulidae) was recovered from all samples under conventional system. The larva length was overall similar between cropping systems. Parasitism by dipteran and hymenopteran, infection by microorganisms, larva mortality by undetermined causes, and differences in viability of S. frugiperda stages were factors contributing with the supression of this pest. The new associations and parasitoids reported represent possibilities of expanding the biological control strategies to manage S. frugiperda in corn crops.


Assuntos
Himenópteros , Mariposas , Humanos , Animais , Masculino , Larva , Spodoptera , Zea mays , Brasil , Agricultura Orgânica
9.
Am J Bot ; 110(12): e16251, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37843974

RESUMO

PREMISE: Phylogeographical studies are fundamental for understanding factors that influence the spatial distribution of genetic lineages within species. Population expansions and contractions, distribution shifts, and climate changes are among the most important factors shaping the genetic compositions of populations. METHODS: We investigated the phylogeography of an endemic oak, Quercus mexicana (Fagaceae), which has a restricted distribution in northeastern Mexico along the Sierra Madre Oriental and adjacent areas. Nuclear and chloroplast DNA microsatellite markers were used to describe the genetic diversity and structure of 39 populations of Q. mexicana along its entire distribution area. We tested whether population expansion or contraction events influenced the genetic diversity and structure of the species. We also modeled the historical distributional range of Q. mexicana (for the Mid Holocene, the Last Glacial Maximum, and the Last Interglacial) to estimate the extent to which climate fluctuations have impacted the distribution of this oak species. RESULTS: Our results revealed high genetic diversity and low genetic structure in Q. mexicana populations. Ecological niche models suggested historical fluctuations in the distributional range of Q. mexicana. Historical range changes, gene flow, and physical barriers seem to have played an important role in shaping the phylogeographic structure of Q. mexicana. CONCLUSIONS: Our study indicates that the genetic structure of Q. mexicana may have been the result of responses of oak trees not only to heterogeneous environments present in the Sierra Madre Oriental and adjacent areas, but also to elevational and latitudinal shifts in response to climate changes in the past.


Assuntos
DNA de Cloroplastos , Quercus , Filogeografia , DNA de Cloroplastos/genética , Quercus/genética , Variação Genética , México , Haplótipos/genética , Filogenia
10.
Cir Cir ; 91(5): 716-718, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37844895

RESUMO

A 40-year-old female with a 24-hour course of abdominal pain suggestive of acute appendicitis. An emergency laparotomy was performed, finding plastron in the cecum and ascending colon, color changes, with purulent liquid and 5 cm in diameter, fixed to Toldt's. It was decided to perform a right hemicolectomy with an ileotransverse end-to-side anastomosis with adequate postsurgical evolution. The histopathological report showed acute purulent diverticulitis of the cecum, which is very low incidence in the Mexican population, that's why this case report is carried out.


Mujer de 40 de años con cuadro de dolor abdominal de 24 h de evolución clínicamente sugestiva de apendicitis aguda. Se realiza laparotomía de urgencia, encontrando plastrón en ciego y colon ascendente, irregular, pétreo, con cambios de coloración, de 5 cm de diámetro, fijo a la fascia de Toldt, con líquido purulento. Se decide realizar hemicolectomía derecha con ileotransverso anastomosis terminolateral, con adecuada evolución posquirúrgica. El reporte histopatológico mostró diverticulitis aguda purulenta de ciego, lo cual es de baja incidencia en la población mexicana, motivo por el que se realiza este reporte de caso.


Assuntos
Apendicite , Doenças do Ceco , Diverticulite , Feminino , Humanos , Adulto , Doenças do Ceco/diagnóstico , Doenças do Ceco/cirurgia , Diverticulite/complicações , Diverticulite/diagnóstico , Diverticulite/cirurgia , Ceco/cirurgia , Apendicite/diagnóstico , Apendicite/cirurgia , Colectomia , Diagnóstico Diferencial
11.
Healthcare (Basel) ; 11(20)2023 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-37893869

RESUMO

Attention deficit hyperactivity disorder (ADHD) is a highly prevalent developmental disorder in children. However, accurately identifying ADHD in early childhood remains a crucial challenge. Electronic health (e-health) systems offer promising possibilities to enhance the diagnostic process for ADHD, particularly concerning the executive functions (EFs) that play a direct role. This study aims to validate an evidence-based tool for screening ADHD through EFs in the school environment. The tool, named Sendero Gris, is designed for tablet devices and is based on a previously validated test with the same name. To ensure its validity, a comparison was made between the results obtained from the tool to be validated and the original format of the test. The analysis revealed no statistically significant differences between the two approaches at a 90% confidence level (p-value = 0.49). Moreover, a user experience study focusing on usability was conducted to assess the children's inclination to use the developed tool, yielding highly positive results. The implementation of Sendero Gris on a tablet device, with its objective and versatile nature, seems to maintain the potential of the original format as a screening tool for ADHD.

12.
Front Aging Neurosci ; 15: 1194203, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37744400

RESUMO

Introduction: Proteolytic processing of amyloid protein precursor by ß-site secretase enzyme (BACE1) is dependent on the cellular lipid composition and is affected by endomembrane trafficking in dementia and Alzheimer's disease (AD). Stearoyl-CoA desaturase 1 (SCD1) is responsible for the synthesis of fatty acid monounsaturation (MUFAs), whose accumulation is strongly associated with cognitive dysfunction. Methods: In this study, we analyzed the relationship between BACE1 and SCD1 in vivo and in vitro neurodegenerative models and their association in familial AD (FAD), sporadic AD (SAD), and cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) using microscopy, biochemical, and mass SPECT approach. Results: Our findings showed that BACE1 and SCD1 immunoreactivities were increased and colocalized in astrocytes of the hippocampus in a rat model of global cerebral ischemia (2-VO). A synergistic effect of double BACE1/SCD1 silencing on the recovery of motor and cognitive functions was obtained. This neuroprotective regulation involved the segregation of phospholipids (PLs) associated with polyunsaturated fatty acids in the hippocampus, cerebrospinal fluid, and serum. The double silencing in the sham and ischemic groups was stronger in the serum, inducing an inverse ratio between total phosphatydilcholine (PC) and lysophosphatidylcholine (LPC), represented mainly by the reduction of PC 38:4 and PC 36:4 and an increase in LPC 16:0 and LPC 18:0. Furthermore, PC 38:4 and PC:36:4 levels augmented in pathological conditions in in vitro AD models. BACE1 and SCD1 increases were confirmed in the hippocampus of FAD, SAD, and CADASIL. Conclusion: Therefore, the findings suggest a novel convergence of BACE-1 and SCD1 in neurodegeneration, related to pro-inflammatory phospholipids.

13.
JMIR Serious Games ; 11: e40284, 2023 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-37099359

RESUMO

BACKGROUND: Currently, many central auditory processing disorder screening tests are available for children, and serious games (SGs) are frequently used as a tool for the diagnosis of different neural deficits and disorders in health care. However, it has not been possible to find a proposal that unifies both ideas. In addition, the validation and improvement of SGs, in general, does not take into account the player-game interaction, thus omitting valuable information about the playability and usability of the game. OBJECTIVE: This study presented Amalia's Planet, a game conceived for use in school environments, which allows a first assessment of a child through their performance of the proposed tasks related to different aspects of auditory performance. In addition, the game defines a series of events in relation to the execution of the tasks, which were evaluated for the subsequent optimization of its performance and the improvement of its usability. METHODS: Using screening tools based on the use of SG technologies, a total of 87 school-age children were evaluated to test the various hypotheses proposed in this study. By grouping users according to whether they had personal history of hearing pathologies, the discriminant power, playability, and usability of the final solution were examined using traditional statistical techniques and process mining (PM) algorithms. RESULTS: With a confidence level of 80% for test 2 (P=.19), there was no statistical evidence to reject the null hypothesis that a player's performance is affected by whether the player had a previous auditory pathology. Furthermore, the tool allowed the screening of 2 players initially categorized as healthy because of their low level of performance in the tests and the similarity of their behavior with that of the group of children with a previous pathology. With regard to the validation of the proposed solution, the use of PM techniques made it possible to detect the existence of events that lasted too long, which can lead to player frustration, and to discover small structural flaws in the game. CONCLUSIONS: SGs seem to be an appropriate tool for the screening of children at risk of central auditory processing disorder. Moreover, the set of PM techniques provides a reliable source of information regarding the playability and usability of the solution to the development team, allowing its continuous optimization.

14.
J Alzheimers Dis ; 90(4): 1437-1447, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36278346

RESUMO

BACKGROUND: Alzheimer's disease (AD) affects women more than men and consequently has been associated with menopause. Tibolone (TIB) has been used as a hormone replacement therapy to alleviate climacteric symptoms. Neuroprotective effects of TIB have also been reported in some animal models. OBJECTIVE: This study aimed to assess the effect of TIB on memory and Aß peptides and tau protein content in the hippocampus and cerebellum of transgenic 3xTgAD ovariectomized mice. METHODS: Three-month-old female mice were ovariectomized. Ten days after surgery, animals were divided into four groups: wild-type (WT)+vehicle; WT+TIB (1 mg/kg); 3xTgAD+vehicle; and 3xTgAD+TIB (1 mg/kg). TIB was administered for three months, and memory was evaluated using the object-in-context recognition task. Subsequently, animals were decapitated, and the hippocampus and cerebellum were dissected. Using commercial ELISA kits, these brain structures were homogenized in a PBS buffer for quantifying Aß40 and Aß42 and phosphorylated and total tau.ResultsA long-term memory deficit was observed in the 3xTgAD+vehicle group. In contrast, TIB treatment improved long-term memory in the 3xTgAD+TIB group than those treated with vehicle (p < 0.05). Furthermore, TIB treatment decreased Aß and tau content in the hippocampus of 3xTgAD mice compared to vehicle-treated groups (p < 0.05). No significant changes were observed in the cerebellum. CONCLUSION: Chronic treatment with TIB showed neuroprotective effects and delayed AD neuropathology in the 3xTgAD mice. Our results support hormone replacement therapy with TIB in menopausal women for neuroprotection.


Assuntos
Doença de Alzheimer , Fármacos Neuroprotetores , Animais , Feminino , Camundongos , Proteínas tau/metabolismo , Peptídeos beta-Amiloides/metabolismo , Doença de Alzheimer/patologia , Modelos Animais de Doenças , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico , Hipocampo/patologia , Camundongos Transgênicos
15.
Arch. bronconeumol. (Ed. impr.) ; 58(8): 595-600, Ag. 2022. ilus, tab, graf
Artigo em Inglês | IBECS | ID: ibc-207051

RESUMO

Introduction: Type 2 (T2) biomarkers such as blood eosinophil count (BEC) and FeNO have been related to a higher risk of exacerbations in COPD. It is unknown whether combining these biomarkers could be useful in forecasting COPD exacerbations. Methods: COPD patients were enrolled in this prospective, multicenter, observational study and followed up for 1 year, during which BEC were analysed at baseline (V0) while FeNO analyses were performed at baseline (V0), 6 months (V1) and 12 months (V2). The risk of moderate or severe exacerbation during follow up was assessed by Cox regression analysis, and the predictive capacity of both measurements was assessed by ROC curves and the DeLong test. Statistical significance was assumed at P<.05. Results: Of the 322 COPD patients initially recruited, 287 were followed up. At baseline, 28.0% were active smokers, and experienced moderate airflow limitation (mean FEV1 56.4%±17.0% predicted). Patients with at least one elevated T2 biomarker (n=125, 42.5%) were at increased risk of COPD exacerbation (HR 1.75, 95% CI 1.25–2.45, P=.001) and of shorter time to first COPD exacerbation. There was no difference between BEC and FeNO regarding the predictive capacity for moderate to severe exacerbation (AUC 0.584 vs 0.576, P=.183) but FeNO predicted severe episodes more accurately than BEC (AUC 0.607 vs 0.539, P<.05). Combining the two biomarkers enhanced the detection of moderate and severe COPD exacerbations. Conclusions: Both eosinophil count and FeNO have limited utility for predicting COPD exacerbations. Combining these T2 biomarkers could enhance the detection of future COPD exacerbations. (AU)


Assuntos
Humanos , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Biomarcadores , Doença Pulmonar Obstrutiva Crônica , Recidiva , Eosinófilos , Estudos Prospectivos , Fumantes , Ex-Fumantes
16.
Front Plant Sci ; 13: 808427, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35548276

RESUMO

Aboveground plant-arthropod interactions are typically complex, involving herbivores, predators, pollinators, and various other guilds that can strongly affect plant fitness, directly or indirectly, and individually, synergistically, or antagonistically. However, little is known about how ongoing natural selection by these interacting guilds shapes the evolution of plants, i.e., how they affect the differential survival and reproduction of genotypes due to differences in phenotypes in an environment. Recent technological advances, including next-generation sequencing, metabolomics, and gene-editing technologies along with traditional experimental approaches (e.g., quantitative genetics experiments), have enabled far more comprehensive exploration of the genes and traits involved in complex ecological interactions. Connecting different levels of biological organization (genes to communities) will enhance the understanding of evolutionary interactions in complex communities, but this requires a multidisciplinary approach. Here, we review traditional and modern methods and concepts, then highlight future avenues for studying the evolution of plant-arthropod interactions (e.g., plant-herbivore-pollinator interactions). Besides promoting a fundamental understanding of plant-associated arthropod communities' genetic background and evolution, such knowledge can also help address many current global environmental challenges.

17.
Dalton Trans ; 51(17): 6607-6621, 2022 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-35383786

RESUMO

The oxidation of Sn(II) to the more stable Sn(IV) degrades the photovoltaic perovskite material CsSnI3; however, this problem can be counteracted via alkaline-earth (AE) doping. In this work, the electronic properties of CsSn1-xAExI3, with x = 0 and 0.25, and AE = Mg and Ca, were investigated via Density Functional Theory. It is proven that the synthetic reactions of all these perovskites are thermodynamically viable. Besides, a slight strengthening in the metal-halide bonds is found in the Mg-doped perovskite; consequently, it exhibits the greatest bulk modulus. Nevertheless, the opposite occurrs with the Ca-doped perovskite, which has the smallest bulk modulus due to the weakening of its metal-halide bonds. The calculated bandgaps for CsSnI3, Mg-doped and Ca-doped perovskites are 1.11, 1.32 and 1.55 eV, respectively, remaining remarkably close to the best photovoltaic-performing value for single-junction solar cells of 1.34 eV. Nevertheless, an indirect bandgap was predicted under Mg-doping. These results support the possibility of implementing AE-doped perovskites as absorber materials in single-junction solar cells, which can deliver higher output voltages than that using CsSnI3. Finally, it was found that Sr or Ba doping could result in semiconductors with bandgaps close to 2.0 eV.

18.
Arch Bronconeumol ; 58(8): 595-600, 2022 Aug.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-35312535

RESUMO

INTRODUCTION: Type 2 (T2) biomarkers such as blood eosinophil count (BEC) and FeNO have been related to a higher risk of exacerbations in COPD. It is unknown whether combining these biomarkers could be useful in forecasting COPD exacerbations. METHODS: COPD patients were enrolled in this prospective, multicenter, observational study and followed up for 1 year, during which BEC were analysed at baseline (V0) while FeNO analyses were performed at baseline (V0), 6 months (V1) and 12 months (V2). The risk of moderate or severe exacerbation during follow up was assessed by Cox regression analysis, and the predictive capacity of both measurements was assessed by ROC curves and the DeLong test. Statistical significance was assumed at P<.05. RESULTS: Of the 322 COPD patients initially recruited, 287 were followed up. At baseline, 28.0% were active smokers, and experienced moderate airflow limitation (mean FEV1 56.4%±17.0% predicted). Patients with at least one elevated T2 biomarker (n=125, 42.5%) were at increased risk of COPD exacerbation (HR 1.75, 95% CI 1.25-2.45, P=.001) and of shorter time to first COPD exacerbation. There was no difference between BEC and FeNO regarding the predictive capacity for moderate to severe exacerbation (AUC 0.584 vs 0.576, P=.183) but FeNO predicted severe episodes more accurately than BEC (AUC 0.607 vs 0.539, P<.05). Combining the two biomarkers enhanced the detection of moderate and severe COPD exacerbations. CONCLUSIONS: Both eosinophil count and FeNO have limited utility for predicting COPD exacerbations. Combining these T2 biomarkers could enhance the detection of future COPD exacerbations.


Assuntos
Doença Pulmonar Obstrutiva Crônica , Biomarcadores , Progressão da Doença , Eosinófilos , Humanos , Estudos Prospectivos
19.
PeerJ ; 9: e11466, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34178440

RESUMO

BACKGROUND: Plants have evolved physical-chemical defense to prevent/diminish damage by their enemies. Chemical defense involves the synthesis' pathways of specialized toxic, repellent, or anti-nutritive metabolites to herbivores. Molecular evolutionary studies have revealed the origin of new genes, acquisition and functional diversification along time in different plant lineages. METHODS: Using bioinformatic tools we analyze gene divergence of tropane alkaloids (TAs) and terpene synthases (TPSs) in Datura stramonium and other species of Solanaceae; compared gene and amino acids sequence of TAs and TPSs on genomes, cDNA and proteins sequences of Viridiplantae. We analyzed two recently assembled genomes of D. stramonium (Ticumán and Teotihuacán), transcriptomes of Datura metel and genomes of other Solanaceae. Hence, we analyzed variation of TAs and TPSs to infer genes involved in plant defense and plant responses before stress. We analyzed protein modeling and molecular docking to predict interactions between H6H and ligand; we translated the sequences (Teo19488, Tic8550 and Tic8549) obtained from the two genomes of D. stramonium by using Swiss-Model and Ramachandran plot and MolProbity structure validation of Teo19488 protein model. RESULTS: For TAs, we detected an expansion event in the tropinone reductase II (TRII) and the ratio synonymous/non-synonymous substitutions indicate positive selection. In contrast, a contraction event and negative selection was detected in tropinone reductase I (TRI). In Hy-oscyamine 6 b-hydroxylase (H6H), enzyme involved in the production of tropane alkaloids atropine and scopolamine, the synonymous/non-synonymous substitution ratio in its dominion indicates positive selection. For terpenes (TPS), we found 18 DsTPS in D. stramomiun and seven in D. metel; evolutionary analyses detected positive selection in TPS10.1 and TPS10.2 of D. stramonium and D. metel. Comparison of copies of TPSs in D. stramonium detected variation among them in the binding site. Duplication events and differentiation of TAs and TPSs of D. stramonium, as compared to other Solanaceae, suggest their possible involvement on adaptive evolution of defense to herbivores. Protein modeling and docking show that the three protein structures obtained of DsH6H from Teo19488, Tic-8550 and Tic8549 maintain the same interactions and the union site of 2OG-FeII_Oxy with the Hy-o ligand as in 6TTM of D. metel. CONCLUSION: Our results indicate differences in the number of gene copies involved in the synthesis of tropane alkaloids, between the genomes of D. stramonium from two Mexican populations. More copies of genes related to the synthesis of tropane alkaloids (TRI, TRII, H6H, PMT) are found in D. stramonium as compared to Viridiplantae. Likewise, for terpene synthases (TPS), TPS-10 is duplicated in D. stramonium and D. metel. Further studies should be directed to experimentally assess gain (overexpression) or loss (silencing) of function of duplicated genes.

20.
Nutr Neurosci ; 24(6): 477-489, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31354109

RESUMO

Introduction: Prolonged ozone exposure can produce a state of oxidative stress, which in turn causes alterations in the dynamics of the brain and affects memory and learning. Moreover, different investigations have shown that high flavonoid content berries show a great antioxidant activity. The relationship between the protective effect of the maqui berry extract and its antioxidant properties in the brain has not been studied in depth. Objectives: The present study evaluated whether the protection exerted by the aqueous extract of maqui berry in brain regions associated with cognitive performance is due to its antioxidant capacity. Methods: Sprague Dawley rats were exposed to 0.25 ppm ozone and administered with maqui berry extracts. At the end of the treatments, spatial learning and short- and long-term memory were evaluated, as well as oxidative stress markers. Results: The administration of 50 and 100 mg/kg of the aqueous extract of maqui berry was effective in preventing the cognitive deficit caused by chronic exposure to ozone. The antioxidant effect of the administration of maqui berry was analyzed in the prefrontal cortex, hippocampus, and amygdala. Oxidative stress markers levels decreased and the enzymatic activity of superoxide dismutase diminished in animals exposed to ozone treated with the 50 mg/kg dose of maqui berry. Discussion: These results show a relationship between protection at the cognitive level and a decrease in oxidative stress markers, which suggests that the prevention of cognitive damage is due to the antioxidant activity of the maqui berry.


Assuntos
Antioxidantes/administração & dosagem , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Memória/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Ozônio/toxicidade , Extratos Vegetais/administração & dosagem , Animais , Frutas , Masculino , Ratos Sprague-Dawley
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