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1.
Nat Commun ; 14(1): 8315, 2023 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-38097648

RESUMEN

The strategies adopted by viruses to reprogram the translation and protein quality control machinery and promote infection are poorly understood. Here, we report that the viral ubiquitin deconjugase (vDUB)-encoded in the large tegument protein of Epstein-Barr virus (EBV BPLF1)-regulates the ribosomal quality control (RQC) and integrated stress responses (ISR). The vDUB participates in protein complexes that include the RQC ubiquitin ligases ZNF598 and LTN1. Upon ribosomal stalling, the vDUB counteracts the ubiquitination of the 40 S particle and inhibits the degradation of translation-stalled polypeptides by the proteasome. Impairment of the RQC correlates with the readthrough of stall-inducing mRNAs and with activation of a GCN2-dependent ISR that redirects translation towards upstream open reading frames (uORFs)- and internal ribosome entry sites (IRES)-containing transcripts. Physiological levels of active BPLF1 promote the translation of the EBV Nuclear Antigen (EBNA)1 mRNA in productively infected cells and enhance the release of progeny virus, pointing to a pivotal role of the vDUB in the translation reprogramming that enables efficient virus production.


Asunto(s)
Infecciones por Virus de Epstein-Barr , Ubiquitina , Humanos , Ubiquitina/metabolismo , Infecciones por Virus de Epstein-Barr/metabolismo , Herpesvirus Humano 4/genética , Herpesvirus Humano 4/metabolismo , Ribosomas/metabolismo , Ubiquitinación , Proteínas/metabolismo , Ubiquitina-Proteína Ligasas/genética , Ubiquitina-Proteína Ligasas/metabolismo , Biosíntesis de Proteínas , Proteínas Portadoras/metabolismo
2.
Health Qual Life Outcomes ; 21(1): 96, 2023 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-37605225

RESUMEN

BACKGROUND: Physical end emotional changes during pregnancy may not only affect pregnant womens' quality of life, but also how instruments assessing quality of life perform in such populations. To date, there is insufficient evidence on psychometric properties for both generic and condition-specific instruments measuring quality of life during pregnancy. The aim of this study was thus to examine the structural validity, internal consistency, and construct validity of the WHOQOL-BREF in a sample of pregnant women. METHODS: A convenience sample of 1015 pregnant women in Sweden completed the WHOQOL-BREF online. We examined the psychometric properties of the instrument using principal component analysis (PCA), confirmatory factor analysis (CFA), Cronbach's alpha, item-domain correlations, correlations with overall QOL and general health, and multiple linear regression with items on overall QOL and general health as outcomes. RESULTS: Principal Component Analysis in a random subsample (n = 502) supported a four-factor model, encompassing the domains physical, psychological, social and environmental quality of life, but with four of the items originally in the environmental domain relocated to the other domains. The proposed domain structure showed good fit in confirmatory factor analysis in the other random subsample (n = 513). The physical and psychological domains showed good internal consistency (Cronbach's alpha = 0.885 and 0.826 respectively), while the social and environmental domains were weaker in this regard. All domains showed significant positive correlations with items on overall QOL and general health. The physical and psychological domains were the most evident predictors in the regression models. CONCLUSIONS: We find the Swedish version of the WHOQOL-BREF to have good psychometric properties to be used in samples of pregnant women, and propose an alternative domain structure that might be even more useful for assessing quality of life during pregnancy. The physical and psychological domains showed good internal consistency and construct validity.


Asunto(s)
Examen Físico , Calidad de Vida , Embarazo , Humanos , Femenino , Reproducibilidad de los Resultados , Psicometría , Emociones
3.
Int J Microbiol ; 2023: 5992113, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37644978

RESUMEN

Isoetes cangae is a native plant found only in a permanent pond in Serra dos Carajás in the Amazon region. Plant-associated microbial communities are recognized to be responsible for biological processes essential for the health, growth, and even adaptation of plants to environmental stresses. In this sense, the aims of this work were to isolate, identify, and evaluate the properties of endophytic bacteria isolated from I. cangae. The bioprospecting of potentially growth-promoting endophytes required the following steps to be taken: isolation of endophytic colonies, molecular identification by 16S rDNA sequence analysis, and evaluation of the bacterial potential for nitrogen fixation, production of indole acetic acid and siderophores, as well as phosphate solubilization and mineralization. Bacillus sp., Rhizobium sp., Priestia sp., Acinetobacter sp., Rossellomorea sp., Herbaspirillum sp., Heyndrickxia sp., and Metabacillus sp., among other bacterial species, were identified. The isolates showed to be highly promising, evidencing the physiological importance for the plant and having the potential to promote plant growth.

4.
Biomolecules ; 13(7)2023 07 06.
Artículo en Inglés | MEDLINE | ID: mdl-37509119

RESUMEN

A unique cytochrome P450 (CYP) oxidoreductase (CPR) sustains activities of human microsomal CYPs. Its function requires toggling between a closed conformation enabling electron transfers from NADPH to FAD and then FMN cofactors and open conformations forming complexes and transferring electrons to CYPs. We previously demonstrated that distinct features of the hinge region linking the FAD and FMN domain (FD) modulate conformer poses and their interactions with CYPs. Specific FD residues contribute in a CYP isoform-dependent manner to the recognition and electron transfer mechanisms that are additionally modulated by the structure of CYP-bound substrate. To obtain insights into the underlying mechanisms, we analyzed how hinge region and FD mutations influence CYP1A2-mediated caffeine metabolism. Activities, metabolite profiles, regiospecificity and coupling efficiencies were evaluated in regard to the structural features and molecular dynamics of complexes bearing alternate substrate poses at the CYP active site. Studies reveal that FD variants not only modulate CYP activities but surprisingly the regiospecificity of reactions. Computational approaches evidenced that the considered mutations are generally in close contact with residues at the FD-CYP interface, exhibiting induced fits during complexation and modified dynamics depending on caffeine presence and orientation. It was concluded that dynamic coupling between FD mutations, the complex interface and CYP active site exist consistently with the observed regiospecific alterations.


Asunto(s)
Cafeína , Citocromo P-450 CYP1A2 , Humanos , Citocromo P-450 CYP1A2/genética , Citocromo P-450 CYP1A2/metabolismo , Sistema Enzimático del Citocromo P-450/metabolismo , Transporte de Electrón , Mutación , NADPH-Ferrihemoproteína Reductasa/genética , NADPH-Ferrihemoproteína Reductasa/química , NADPH-Ferrihemoproteína Reductasa/metabolismo
5.
Genes (Basel) ; 13(11)2022 10 29.
Artículo en Inglés | MEDLINE | ID: mdl-36360213

RESUMEN

The altered activity of drug metabolism enzymes (DMEs) is a hallmark of chemotherapy resistance. Cytochrome P450s (CYPs), mainly CYP3A4, and several oxidoreductases are responsible for Phase I metabolism of doxorubicin (DOX), an anthracycline widely used in breast cancer (BC) treatment. This study aimed to investigate the role of Phase I DMEs involved in the first stages of acquisition of DOX-resistance in BC cells. For this purpose, the expression of 92 DME genes and specific CYP-complex enzymes activities were assessed in either sensitive (MCF-7 parental cells; MCF-7/DOXS) or DOX-resistant (MCF-7/DOXR) cells. The DMEs genes detected to be significantly differentially expressed in MCF-7/DOXR cells (12 CYPs and eight oxidoreductases) were indicated previously to be involved in tumor progression and/or chemotherapy response. The analysis of CYP-mediated activities suggests a putative enhanced CYP3A4-dependent metabolism in MCF-7/DOXR cells. A discrepancy was observed between CYP-enzyme activities and their corresponding levels of mRNA transcripts. This is indicative that the phenotype of DMEs is not linearly correlated with transcription induction responses, confirming the multifactorial complexity of this mechanism. Our results pinpoint the potential role of specific CYPs and oxidoreductases involved in the metabolism of drugs, retinoic and arachidonic acids, in the mechanisms of chemo-resistance to DOX and carcinogenesis of BC.


Asunto(s)
Resistencia a Antineoplásicos , Neoplasias , Resistencia a Antineoplásicos/genética , Citocromo P-450 CYP3A/genética , Doxorrubicina/farmacología , Antibióticos Antineoplásicos/farmacología
6.
Front Psychol ; 13: 936053, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36300042

RESUMEN

This research was conducted with two main goals-to contribute to knowledge on the development of empathy from early adolescence to adulthood, including its contribution to decoding emotion expression, and to improve the understanding of the nature of empathy by simultaneously assessing empathy toward two different targets-humans and animals. It unfolded into two cross-sectional studies: One (S1) obtaining measures of empathy toward humans and animals as targets across five age groups (from pre-adolescents to adults); and another (S2) where a subset of the adolescents who participated in S1 were assessed in emotion expression decoding and subjective and physiological responses to emotional video clips. The results of S1 showed that empathy toward animals and most dimensions of empathy toward humans increase toward adulthood, with important gender differences in empathy to animals and humans, and empathy levels in girls starting off in the age trajectory at higher levels, A moderate correlation between empathy toward human and toward animal targets was also found. S2 showed that the expression of positive emotion is better recognized than that of negative emotion, surprise, or neutral expression, and that the measure of human-directed empathy predicts successful decoding of negative emotion, whereas skin conductance responses (SCRs) and subjective valence ratings predicted successful identification of positive emotion. Gender differences emerged but not across all age groups nor all subscales. Results yield keys to the developmental "pace" and trajectory of the various dimensions of empathy and to how empathy relates to emotion decoding.

7.
Front Psychol ; 13: 720606, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35465494

RESUMEN

A field study collecting behavioral data was conducted to investigate effects of behavioral interventions, commonly known as nudges, in promoting the consumption of organic fruits and vegetables. Consumption, both organically and conventionally produced fruits and vegetables, was measured in a grocery store during 4 days (1 day every other week) where consumers were exposed to informational messages in combination with either emotional images or social norm messages. Measurements of daily consumption without exposure to nudges were carried out during four other days (1 day every other week, alternated with the nudging days). The results showed no effect of the nudging strategy; instead, it pointed to the importance of the price as a determinant of buying decisions. Buying ecological alternatives was associated with lower price differences between the ecological and non-ecological alternatives. We conclude that combined nudges and collected psychological data from participants may contribute to more successful nudging interventions. Some political measures in balancing the price difference between organically and conventionally produced products might also be interesting strategies in order to promote the consumption of organic fruits and vegetables.

10.
Ecol Evol ; 11(15): 10119-10132, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34367563

RESUMEN

The quillwort Isoëtes cangae is a critically endangered species occurring in a single lake in Serra dos Carajás, Eastern Amazon. Low genetic diversity and small effective population sizes (N e) are expected for narrow endemic species (NES). Conservation biology studies centered in a single species show some limitations, but they are still useful considering the limited time and resources available for protection of species at risk of extinction. Here, we evaluated the genetic diversity, population structure, N e, and minimum viable population (MVP) of I. cangae to provide information for effective conservation programs. Our analyses were based on 55 individuals collected from the Amendoim Lake and 35,638 neutral SNPs. Our results indicated a single panmictic population, moderate levels of genetic diversity, and N e in the order of thousands, contrasting the expected for NES. Negative FIS values were also found, suggesting that I. cangae is not under risk of inbreeding depression. Our findings imply that I. cangae contains enough genetic diversity to ensure evolutionary potential and that all individuals should be treated as one demographic unit. These results provide essential information to optimize ex situ conservation efforts and genetic diversity monitoring, which are currently applied to guide I. cangae conservation plans.

11.
J Xenobiot ; 11(3): 94-114, 2021 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-34206277

RESUMEN

Human Cytochrome P450 (CYP) enzymes constitute a superfamily of membrane-bound hemoproteins that are responsible for the metabolism of a wide variety of clinically, physiologically, and toxicologically important compounds. These heme-thiolate monooxygenases play a pivotal role in the detoxification of xenobiotics, participating in the metabolism of many structurally diverge compounds. This short-review is intended to provide a summary on the major roles of CYPs in Phase I xenobiotic metabolism. The manuscript is focused on eight main topics that include the most relevant aspects of past and current CYP research. Initially, (I) a general overview of the main aspects of absorption, distribution, metabolism, and excretion (ADME) of xenobiotics are presented. This is followed by (II) a background overview on major achievements in the past of the CYP research field. (III) Classification and nomenclature of CYPs is briefly reviewed, followed by (IV) a summary description on CYP's location and function in mammals. Subsequently, (V) the physiological relevance of CYP as the cornerstone of Phase I xenobiotic metabolism is highlighted, followed by (VI) reviewing both genetic determinants and (VI) nongenetic factors in CYP function and activity. The last topic of the review (VIII) is focused on the current challenges of the CYP research field.

12.
Healthcare (Basel) ; 9(4)2021 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-33916533

RESUMEN

The present study sought to contribute to a better understanding of children's attitudes and behaviors regarding oral health and dental practices. The sample was composed of 101 children (8-10 years), collected from several schools in the Lisbon metropolitan area. Our main goals were to collect a survey of information about the beliefs, attitudes, habits and knowledge of children about oral and dental issues in order to not only have an overview of them but also to serve as a basis and a starting point for the development of intervention programs to increase positive attitudes and behaviors related to oral health and promote greater knowledge about these subjects. In general, children reported positive behaviors regarding dental habits and oral hygiene practices. Children's opinions and beliefs about dentists were also globally positive; however, the results suggested that younger children reported more positive attitudes, emotions and previous experiences. Regarding children's knowledge about these dental issues, the results were quite negative and worrying, ruled by ignorance and incorrect beliefs and behaviors. In sum, all the results and conclusions of this study may contribute to the development of educational programs within the scope of the promotion of oral health and hygiene practices-"An Adventure about Oral Health."

13.
PeerJ ; 8: e10274, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33240624

RESUMEN

BACKGROUND: Two endemic lycophyte species Isoetes cangae and Isoetes serracarajensis have been recently described in the State of Pará in the Amazon forest located in northern Brazil. Isoetes L. has survived through three mass extinctions. Plants are considered small-sized, heterosporous, and can display a great diversity of physiological adaptations to different environments. Thus, the current study aimed to estimate the genetic variation of the populations of I. cangae and I. serracarajensis to generate information about their different mechanisms for survival at the same geographical location that could point to different reproductive, adaptative and dispersal strategies and should be considered for effective conservation strategies. METHODS: The genetic diversity and population structure of I. cangae and I. serracarajensis were investigated using Inter Simple Sequence Repeat (ISSR) molecular markers. Total genomic DNA was isolated, and the genetic diversity parameters were calculated. RESULTS: The sixteen primers produced 115 reproducible bands, 87% of which were polymorphic. A high level of polymorphic loci (81.74% and 68.48%) and a high Shannon index (Sh = 0.376 and 0.289) were observed for I. cangae and I. serracarajensis, respectively. The coefficient of genetic differentiation between population areas (GST) showed a higher value in I. serracarajensis (0.5440). Gene flow was higher in I. cangae (1.715) and lower in I. serracarajensis populations (0.419). Overall, the results further show that I. serracarajensis and I. cangae are two species with considerable genetic variation and that these differences may reflect their habitats and modes of reproduction. These results should be considered in the development of effective conservation strategies for both species.

14.
Environ Monit Assess ; 192(11): 708, 2020 Oct 17.
Artículo en Inglés | MEDLINE | ID: mdl-33068209

RESUMEN

This study aimed to compare the efficiency of two different sizes of the Surber sampler to assess benthic macroinvertebrates in headwater streams in two Amazonian regions. Two Surber samplers of different sizes were used, one measuring 20 × 20 cm and the other 30 × 30 cm, both with a 0.25-mm net. The number of replicates taken was 6 for the smaller sampler and 3 for the bigger one, maintaining approximately the same total sampled area. The study was carried out in 12 headwater streams with different environmental conditions. Biological metrics were calculated for each size at each site and compared within each stream health category. A two-way analysis of similarities test was performed to compare the community structure assessed by each method at each stream. A normalized sampling effort was used to quantify the number of samples required to correctly sample each site. The data did not show a significant difference between the two sizes regarding the taxonomic recruitment and the community structure sampled at each stream, but differences were found between the two sizes in dominance values and in Shannon index scores for the natural sites. Furthermore, the smaller Surber was able to assess 70% of the estimated richness in all sites, which suggests that it is better to assess benthic macroinvertebrates than the larger Surber. Moreover, the smaller Surber is easier to transport in the field, reducing the effort of the technician, and takes less time to sort the material collected with it, which can reduce the sample processing effort, therefore reducing the cost of the project.


Asunto(s)
Invertebrados , Ríos , Animales , Biodiversidad , Monitoreo Biológico , Monitoreo del Ambiente
15.
Int J Mol Sci ; 21(18)2020 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-32933097

RESUMEN

The activity of microsomal cytochromes P450 (CYP) is strictly dependent on the supply of electrons provided by NADPH cytochrome P450 oxidoreductase (CPR). The variant nature of the isoform-specific proximal interface of microsomal CYPs implies that the interacting interface between the two proteins is degenerated. Recently, we demonstrated that specific CPR mutations in the FMN-domain (FD) may induce a gain in activity for a specific CYP isoform. In the current report, we confirm the CYP isoform dependence of CPR's degenerated binding by demonstrating that the effect of four of the formerly studied FD mutants are indeed exclusive of a specific CYP isoform, as verified by cytochrome c inhibition studies. Moreover, the nature of CYP's substrate seems to have a modulating role in the CPR:CYP interaction. In silico molecular dynamics simulations of the FD evidence that mutations induces very subtle structural alterations, influencing the characteristics of residues formerly implicated in the CPR:CYP interaction or in positioning of the FMN moiety. CPR seems therefore to be able to form effective interaction complexes with its structural diverse partners via a combination of specific structural features of the FD, which are functional in a CYP isoform dependent manner, and dependent on the substrate bound.


Asunto(s)
Sistema Enzimático del Citocromo P-450/metabolismo , NADPH-Ferrihemoproteína Reductasa/metabolismo , Citocromos c/metabolismo , Escherichia coli/metabolismo , Humanos , Mutación/genética , Unión Proteica/fisiología , Isoformas de Proteínas/metabolismo
18.
Front Pharmacol ; 11: 299, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32256365

RESUMEN

NADPH cytochrome P450 oxidoreductase (CPR) is the obligatory electron supplier that sustains the activity of microsomal cytochrome P450 (CYP) enzymes. The variant nature of the isoform-specific proximal interface of microsomal CYPs indicates that CPR is capable of multiple degenerated interactions with CYPs for electron transfer, through different binding mechanisms, and which are still not well-understood. Recently, we showed that CPR dynamics allows formation of open conformations that can be sampled by its structurally diverse redox partners in a CYP-isoform dependent manner. To further investigate the role of the CPR FMN-domain in effective binding of CPR to its diverse acceptors and to clarify the underlying molecular mechanisms, five different CPR-FMN-domain random mutant libraries were created. These libraries were screened for mutants with increased activity when combined with specific CYP-isoforms. Seven CPR-FMN-domain mutants were identified, supporting a gain in activity for CYP1A2 (P117H, G144C, A229T), 2A6 (P117L/L125V, G175D, H183Y), or 3A4 (N151D). Effects were evaluated using extended enzyme kinetic analysis, cytochrome b 5 competition, ionic strength effect on CYP activity, and structural analysis. Mutated residues were located either in or adjacent to several acidic amino acid stretches - formerly indicated to be involved in CPR:CYP interactions - or close to two tyrosine residues suggested to be involved in FMN binding. Several of the identified positions co-localize with mutations found in naturally occurring CPR variants that were previously shown to cause CYP-isoform-dependent effects. The mutations do not seem to significantly alter the geometry of the FMN-domain but are likely to cause very subtle alterations leading to improved interaction with a specific CYP. Overall, these data suggest that CYPs interact with CPR using an isoform specific combination of several binding motifs of the FMN-domain.

19.
Sci Rep ; 10(1): 5626, 2020 03 27.
Artículo en Inglés | MEDLINE | ID: mdl-32221401

RESUMEN

Biotic resistance mediated by native plant diversity has long been hypothesized to reduce the success of invading plant species in terrestrial systems in temperate regions. However, still little is known about the mechanisms driving invasion patterns in other biomes or latitudes. We help to fill this gap by investigating how native plant community presence and diversity, and the presence of native phylogenetically closely related species to an invader, would affect invader Hydrilla verticillata establishment success in tropical freshwater submerged plant communities. The presence of a native community suppressed the growth of H. verticillata, but did not prevent its colonisation. Invader growth was negatively affected by native plant productivity, but independent of native species richness and phylogenetic relatedness to the invader. Native plant production was not related to native species richness in our study. We show that resistance in these tropical aquatic submerged plant communities is mainly driven by the presence and biomass of a native community independent of native species diversity. Our study illustrates that resistance provided by these tropical freshwater submerged plant communities to invasive species contrasts to resistance described for other ecosystems. This emphasizes the need to include understudied systems when predicting patterns of species invasiveness and ecosystem invasibility across biomes.


Asunto(s)
Hydrocharitaceae/fisiología , Fenómenos Bioquímicos/genética , Biodiversidad , Biomasa , Ecosistema , Agua Dulce , Hydrocharitaceae/genética , Especies Introducidas , Filogenia , Dinámica Poblacional
20.
Autism ; 24(1): 233-245, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31238707

RESUMEN

Humans are commonly motivated towards cooperation and prosociality. In this study, we examined this motivational predisposition in autistic individuals. Using an adaptation of the Cyberball paradigm, we investigated subsequent pro-social behaviour after witnessing social exclusion. Participants witnessed and played a series of Cyberball games, rated their affective state and valued emotional faces with respect to their approachability. Results showed that participants from both groups were aware of the social exclusion. However, while neurotypically developing participants engaged in pro-social behaviour in reaction to the exclusion, autistic participants showed less alterations, in terms of either behaviour or affective state. The current findings suggest a distinct motivational drive and processing of social reward stimuli in autism, which may result in behavioural responses divergent from typical development when engaging in the social world.


Asunto(s)
Trastorno del Espectro Autista/psicología , Relaciones Interpersonales , Motivación , Distancia Psicológica , Habilidades Sociales , Adolescente , Adulto , Niño , Femenino , Humanos , Masculino , Adulto Joven
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