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1.
Pestic Biochem Physiol ; 199: 105777, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38458684

RESUMEN

The fall armyworm (Spodoptera frugiperda) is a major global pest causing severe damage to various crops, especially corn. Transgenic corn producing the Cry1F pesticidal protein from the bacterium Bacillus thuringiensis (Cry1F corn) showed effectiveness in controlling this pest until S. frugiperda populations at locations in North and South America evolved practical resistance. The mechanism for practical resistance involved disruptive mutations in an ATP binding cassette transporter subfamily C2 gene (SfABCC2), which serves as a functional Cry1F receptor in the midgut cells of susceptible S. frugiperda. The SfABCC2 protein contains two transmembrane domains (TMD1 and TMD2), each with a cytosolic nucleotide (ATP) binding domain (NBD1 and NBD2, respectively). Previous reports have demonstrated that disruptive mutations in TMD2 were linked with resistance to Cry1F, yet whether the complete SfABCC2 structure is needed for receptor functionality or if a single TMD-NBD protein can serve as functional Cry1F receptor remains unknown. In the present study, we separately expressed TMD1 and TMD2 with their corresponding NBDs in cultured insect cells and tested their Cry1F receptor functionality. Our results show that the complete SfABCC2 structure is required for Cry1F receptor functionality. Moreover, binding competition assays revealed that Cry1F specifically bound to SfABCC2, whereas neither SfTMD1-NBD1 nor SfTMD2-NBD2 exhibited any significant binding. These results provide insights into the molecular mechanism of Cry1F recognition by SfABCC2 in S. frugiperda, which could facilitate the development of more effective insecticidal proteins.


Asunto(s)
Bacillus thuringiensis , Endotoxinas , Animales , Spodoptera , Endotoxinas/genética , Resistencia a los Insecticidas/genética , Toxinas de Bacillus thuringiensis/metabolismo , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Bacillus thuringiensis/metabolismo , Zea mays , Proteínas Hemolisinas/genética , Plantas Modificadas Genéticamente/genética
2.
Nurs Ethics ; 31(1): 65-78, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38111341

RESUMEN

The assessment of learning in the ethical domain is one of the most complex aspects to attend in the educational context. In recent years, character education has contributed greatly to different social disciplines, such as education or nursing. However, the development of this approach has run up against several obstacles and limitations, as there is little evidence regarding its long-term effectiveness or its evaluation. This essay aims to identify some of the main difficulties to assess learning in the ethical domain, as obstacles and possible constraints to Aristotelian-based character education. Methodology is analytical and of a philosophical-educational nature, based on which an argumentative analysis is constructed from the bibliographical review of the contributions of classical and contemporary authors. Results show the existence of four major problems and ten associated subproblems, both of an external nature linked to the contextual factors of assessment, and of an internal nature that affect the essence of the process itself, which highlight the difficulty of carrying out assessments of an ethical kind. Far from proposing a pessimistic position, we argue a realistic vision that allows educators at different educational levels to be aware of the limits and critical points of evaluation in the ethical domain.


Asunto(s)
Aprendizaje , Humanos , Escolaridad
3.
Appl Environ Microbiol ; 89(12): e0164423, 2023 12 21.
Artículo en Inglés | MEDLINE | ID: mdl-38014960

RESUMEN

IMPORTANCE: Helicoverpa zea is a major crop pest in the United States that is managed with transgenic corn and cotton that produce insecticidal proteins from the bacterium, Bacillus thuringiensis (Bt). However, H. zea has evolved widespread resistance to the Cry proteins produced in Bt corn and cotton, leaving Vip3Aa as the only plant-incorporated protectant in Bt crops that consistently provides excellent control of H. zea. The benefits provided by Bt crops will be substantially reduced if widespread Vip3Aa resistance develops in H. zea field populations. Therefore, it is important to identify resistance alleles and mechanisms that contribute to Vip3Aa resistance to ensure that informed resistance management strategies are implemented. This study is the first report of reduced binding of Vip3Aa to midgut receptors associated with resistance.


Asunto(s)
Bacillus thuringiensis , Mariposas Nocturnas , Animales , Estados Unidos , Zea mays/metabolismo , Endotoxinas/metabolismo , Resistencia a los Insecticidas/genética , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Plantas Modificadas Genéticamente/metabolismo , Proteínas Hemolisinas/genética , Mariposas Nocturnas/genética , Bacillus thuringiensis/genética , Larva/metabolismo
4.
Photochem Photobiol Sci ; 22(8): 1855-1864, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37120781

RESUMEN

The prediction of band edge potentials in photocatalytic materials is an important but challenging task. In contrast, bandgaps can be easily determined through absorption spectra. Here, we present two simple theoretical approaches for the determination of band edge potentials which are based on the electron negativity and work function of each constituent atom. We use these approaches to determine band edge potentials in semiconducting metallic oxides and sulfides, such as titanium dioxide (TiO2), chalcopyrite (CuFeS2), pyrite (FeS2), covellite (CuS), and chalcocite (Cu2S) with respect to an absolute scale (eV) and an electrochemical scale (V). Until now, there is little information on iron and copper sulfides referring to these thermodynamic parameters. TiO2 (Titania p25) was used as reference semiconductor to validate the calculation procedures using experimental values by X-ray diffraction analysis (XRD), diffuse reflectance spectrometry (DRS), and electron paramagnetic resonance spectroscopy (EPR). The production of key chemical species such as reactive oxygen species (ROS) and reactive sulfur species (RSS) has been theoretically and experimentally determined by EPR.

5.
J Appl Clin Med Phys ; 24(9): e14053, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37247259

RESUMEN

PURPOSE: The CyberKnife quality assurance (QA) program relies mainly on the use of radiochromic film (RCF). We aimed at evaluating high-resolution arrays of detectors as an alternative to films for CyberKnife machine QA. METHODS: This study will test the SRS Mapcheck (Sun Nuclear, Melbourne, Florida, USA) diode array and its own software, which allows three tests of the CyberKnife QA program to be performed. The first one is a geometrical accuracy test based on the delivery of two orthogonal beams (Automated Quality Assurance, AQA). Besides comparing the constancy and repeatability of both methods, known errors will be introduced to check their sensitivity. The second checks the constancy of the iris collimator field sizes (Iris QA). Changes in the field sizes will be introduced to study the array sensitivity. The last test checks the correct positioning of the multileaf collimator (MLC). It will be tested introducing known systematic displacements to whole banks and to single leaves. RESULTS: The results of the RCF and diode array were equivalent (maximum differences of 0.18 ± 0.14 mm) for the AQA test, showing the array a higher reproducibility. When known errors were introduced, both methods behaved linearly with similar slopes. Regarding Iris QA, the array measurements are highly linear when changes in the field sizes are introduced. Linear regressions show slopes of 0.96-1.17 with r2 above 0.99 in all field sizes. Diode array seems to detect changes of 0.1 mm. In MLC QA, systematic errors of the whole bank of leaves were not detected by the array, while single leaf errors were detected. CONCLUSIONS: The diode array is sensitive and accurate in the AQA and Iris QA tests, which give us the possibility of substituting RCF with a diode array. QA would be performed faster than using the film procedure, obtaining reliable results. Regarding the MLC QA, the inability to detect systematic displacements make it difficult to confidently use the detector.


Asunto(s)
Radioterapia de Intensidad Modulada , Programas Informáticos , Humanos , Reproducibilidad de los Resultados , Garantía de la Calidad de Atención de Salud/métodos , Radioterapia de Intensidad Modulada/métodos , Planificación de la Radioterapia Asistida por Computador , Dosificación Radioterapéutica
6.
J Appl Clin Med Phys ; 24(8): e14006, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37097754

RESUMEN

PURPOSE: To study and analyze the effect of the use of a thin guide-wire instead of a Foley catheter for urethral definition in prostate stereotactic body radiation therapy (SBRT) treatments and to compare treatment parameters in both situations. MATERIAL AND METHODS: Thirty-seven prostate SBRT patients were employed in this study. A Foley catheter was employed in nine of them, and a guide-wire was employed in the other 28 patients. For each of the 28 patients in which the guide-wire was employed, a comparison between urethral positions in both situations was performed, allowing for a margin definition of the urethra when a Foley catheter was employed. Displacements of the prostate during treatment were obtained, allowing for an analysis of prostate positions in both situations. Also, different treatment parameters such as the number of treatment interruptions, couch movements performed, and x-rays needed were gathered. RESULTS: Large differences between urethral positions can be found in the anterior-posterior (AP) directions compared to those in the lateral (LAT) direction. Differences are also larger in areas closer to the base of the prostate, where margins applied in the case of using a Foley catheter are 16 mm with a mean displacement of 6 mm in the posterior direction. No differences in the treatment parameters were found during treatment in both situations. The difference found in absolute prostate pitch rotations suggests that the Foley catheter provokes a shift of the prostate position, which does not occur when employing the guide-wire. CONCLUSIONS: Foley catheters shift the urethral position, making them a wrong surrogate of the urethra when no catheters are present. The margins needed to assess uncertainties introduced by the use of a Foley catheter are larger than those usually applied. The use of a Foley catheter did not present any additional difficulty during treatment delivery in terms of images employed or interruptions produced.


Asunto(s)
Neoplasias de la Próstata , Radiocirugia , Masculino , Humanos , Uretra , Próstata , Neoplasias de la Próstata/radioterapia , Neoplasias de la Próstata/cirugía , Cateterismo Urinario
7.
Angew Chem Int Ed Engl ; 62(21): e202301356, 2023 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-36944060

RESUMEN

We report the synthesis and characterization of a novel type of nanohoop, consisting of a cycloparaphenylene derivative incorporating a curved heptagon-containing π-extended polycyclic aromatic hydrocarbon (PAH) unit. We demonstrate that this new macrocycle behaves as a supramolecular receptor of curved π-systems such as fullerenes C60 and C70 , with remarkably large binding constants (ca. 107  M-1 ), as estimated by fluorescence measurements. Nanosecond and femtosecond spectroscopic analysis show that these host-guest complexes are capable of quasi-instantaneous charge separation upon photoexcitation, due to the ultrafast charge transfer from the macrocycle to the complexed fullerene. These results demonstrate saddle-shaped PAHs with dibenzocycloheptatrienone motifs as structural components for new macrocycles displaying molecular receptor abilities and versatile photochemical responses with promising electron-donor properties in host-guest complexes.

8.
J Phys Chem A ; 126(48): 8997-9007, 2022 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-36413983

RESUMEN

Rhenium(I) tricarbonyl complexes have been described as suitable fluorophores, particularly for biological applications. fac-[Re(CO)3(N,N)L](0 or 1+) complexes, where N,N is a substituted dinitrogenated ligand (bipyridine or derivatives with relatively small substituents) and L the ancillary ligand [a pyridine Schiff base (PSB) harboring an intramolecular hydrogen bond (IHB)], have presented promissory results concerning their use as fluorophores, especially for walled cells (i.e., bacteria and fungi). In this work, we present a relativistic theoretical analysis of two series of fac-[Re(CO)3(N,N)PSB]1+ complexes to predict the role of the IHB in the ancillary ligand concerning their photophysical behavior. N,N corresponds to 2,2'-bipyridine (bpy) (series A) or 4,4'-bis(ethoxycarbonyl)-2,2'-bipyridine (deeb) (series B). We found that all the complexes present absorption in the visible light range. In addition, complexes presenting a PSB with an IHB exhibit luminescent emission suitable for biological purposes: large Stokes shift, emission in the range of 600-700 nm, and τ in the order of 10-2 to 10-3 s. By contrast, complexes with PSB lacking the IHB show a predicted emission with the lowest triplet excited-state energy entering the NIR region. These results suggest a role of the IHB as an important switcher between visible and NIR emissions in this kind of complexes. Since the PSB can be substituted to modulate the properties of the whole Re(I) complex, it will be interesting to explore whether other substitutions can also affect the photophysical properties, mainly the emission range.


Asunto(s)
2,2'-Dipiridil , Bases de Schiff , Enlace de Hidrógeno , Ligandos
9.
Int J Mol Sci ; 23(5)2022 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-35269699

RESUMEN

Searching for adequate and effective compounds displaying antimicrobial activities, especially against Gram-positive bacteria, is an important research area due to the high hospitalization and mortality rates of these bacterial infections in both the human and veterinary fields. In this work, we explored (E)-4-amino-3-((3,5-di-tert-butyl-2-hydroxybenzylidene)amino) benzoic acid (SB-1, harboring an intramolecular hydrogen bond) and (E)-2-((4-nitrobenzilidene)amino)aniline (SB-2), two Schiff bases derivatives. Results demonstrated that SB-1 showed an antibacterial activity determined by the minimal inhibitory concentration (MIC) against Staphylococcus aureus, Enterococcus faecalis, and Bacillus cereus (Gram-positive bacteria involved in human and animal diseases such as skin infections, pneumonia, diarrheal syndrome, and urinary tract infections, among others), which was similar to that shown by the classical antibiotic chloramphenicol. By contrast, this compound showed no effect against Gram-negative bacteria (Klebsiella pneumoniae, Escherichia coli, and Salmonella enterica). Furthermore, we provide a comprehensive physicochemical and theoretical characterization of SB-1 (as well as several analyses for SB-2), including elemental analysis, ESMS, 1H and 13C NMR (assigned by 1D and 2D techniques), DEPT, UV-Vis, FTIR, and cyclic voltammetry. We also performed a computational study through the DFT theory level, including geometry optimization, TD-DFT, NBO, and global and local reactivity analyses.


Asunto(s)
Bacterias Grampositivas , Bases de Schiff , Animales , Antibacterianos/química , Antibacterianos/farmacología , Escherichia coli , Bacterias Gramnegativas , Pruebas de Sensibilidad Microbiana , Bases de Schiff/química , Bases de Schiff/farmacología
10.
J Sport Rehabil ; 31(4): 398-413, 2022 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-35078147

RESUMEN

OBJECTIVES: To evaluate the efficacy of 24 weeks of treatment with Mézières method in a Spanish elite second-division soccer team with low back pain (LBP), analyzing their state of back health, flexibility, pain, and steps speed. DESIGN: Double-blind randomized controlled trial. METHODS: A total of 20 players with LBP from the second soccer division league were allocated equally to the experimental and control groups (n = 10) as per selection criteria and participated in 2 different rehabilitation programs. The postural Mézières method was implemented in the experimental group, whereas the standard European treatment protocol for LBP was implemented in the control group. Both treatments had a twice weekly session of 40 minutes duration for 24 weeks consecutively with a follow-up in the fourth, 12th, and 24th weeks. RESULTS: Multivariate analysis of covariance with the baseline assessment as a covariance showed a significant difference between groups at the 12th and 24th weeks of the treatment for pain and back functionality. A relevant difference between the experimental and control groups was shown only at the 24th week of the treatment (P < .05) for back flexibility. A significant difference between groups was reported for the quality of life scale and steps speed at the 24th week of the treatment (P > .05). CONCLUSION: The Mézières method showed a positive effect in the elite soccer athletes with nonspecific chronic LBP and can be used as an alternative treatment.


Asunto(s)
Dolor de la Región Lumbar , Fútbol , Atletas , Método Doble Ciego , Humanos , Dolor de la Región Lumbar/terapia , Calidad de Vida
11.
Angew Chem Int Ed Engl ; 61(37): e202208591, 2022 09 12.
Artículo en Inglés | MEDLINE | ID: mdl-35856293

RESUMEN

We present the first helicene carbon nanoohop that integrates a [6]helicene into [7]cycloparaphenylene. The [6]helicene endows the helicene carbon nanohoop with chiroptical properties and configurational stability typical for higher helicenes, while the radially conjugated seven para-phenylenes largely determine the optoelectronic properties. The structure of the helicene carbon nanoohop was unambiguously characterized by NMR, MS and X-ray analysis that revealed that it possesses a topology of a Möbius strip in the solid state and in solution. The chirality transfers from the [6]helicene to the para-phenylenes and leads to a pronounced circular dichroism and bright circularly polarized luminescence, which is affected by the structural topology of the nanohoop.


Asunto(s)
Luminiscencia , Compuestos Policíclicos , Carbono , Compuestos Policíclicos/química , Estereoisomerismo
12.
Angew Chem Int Ed Engl ; 61(14): e202111816, 2022 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-35077609

RESUMEN

The chemical processing of low-dimensional carbon nanostructures is crucial for their integration in future devices. Here we apply a new methodology in atomically precise engineering by combining multistep solution synthesis of N-doped molecular graphene nanoribbons (GNRs) with mass-selected ultra-high vacuum electrospray controlled ion beam deposition on surfaces and real-space visualisation by scanning tunnelling microscopy. We demonstrate how this method yields solely a controllable amount of single, otherwise unsublimable, GNRs of 2.9 nm length on a planar Ag(111) surface. This methodology allows for further processing by employing on-surface synthesis protocols and exploiting the reactivity of the substrate. Following multiple chemical transformations, the GNRs provide reactive building blocks to form extended, metal-organic coordination polymers.

13.
Annu Rev Entomol ; 66: 121-140, 2021 01 07.
Artículo en Inglés | MEDLINE | ID: mdl-33417820

RESUMEN

Insecticidal proteins from the bacterium Bacillus thuringiensis (Bt) are used in sprayable formulations or produced in transgenic crops as the most successful alternatives to synthetic pesticides. The most relevant threat to sustainability of Bt insecticidal proteins (toxins) is the evolution of resistance in target pests. To date, high-level resistance to Bt sprays has been limited to one species in the field and another in commercial greenhouses. In contrast, there are currently seven lepidopteran and one coleopteran species that have evolved practical resistance to transgenic plants producing insecticidal Bt proteins. In this article, we present a review of the current knowledge on mechanisms of resistance to Bt toxins, with emphasis on key resistance genes and field-evolved resistance, to support improvement of Bt technology and its sustainability.


Asunto(s)
Toxinas de Bacillus thuringiensis , Proteínas Bacterianas , Endotoxinas , Proteínas Hemolisinas , Insectos/genética , Alelos , Animales , Control de Insectos , Resistencia a los Insecticidas/genética
14.
BMC Genomics ; 22(1): 179, 2021 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-33711916

RESUMEN

BACKGROUND: The fall armyworm (Spodoptera frugiperda (J.E. Smith)) is a highly polyphagous agricultural pest with long-distance migratory behavior threatening food security worldwide. This pest has a host range of > 80 plant species, but two host strains are recognized based on their association with corn (C-strain) or rice and smaller grasses (R-strain). The population genomics of the United States (USA) fall armyworm remains poorly characterized to date despite its agricultural threat. RESULTS: In this study, the population structure and genetic diversity in 55 S. frugiperda samples from Argentina, Brazil, Kenya, Puerto Rico and USA were surveyed to further our understanding of whole genome nuclear diversity. Comparisons at the genomic level suggest a panmictic S. frugiperda population, with only a minor reduction in gene flow between the two overwintering populations in the continental USA, also corresponding to distinct host strains at the mitochondrial level. Two maternal lines were detected from analysis of mitochondrial genomes. We found members from the Eastern Hemisphere interspersed within both continental USA overwintering subpopulations, suggesting multiple individuals were likely introduced to Africa. CONCLUSIONS: Our research is the largest diverse collection of United States S. frugiperda whole genome sequences characterized to date, covering eight continental states and a USA territory (Puerto Rico). The genomic resources presented provide foundational information to understand gene flow at the whole genome level among S. frugiperda populations. Based on the genomic similarities found between host strains and laboratory vs. field samples, our findings validate the experimental use of laboratory strains and the host strain differentiation based on mitochondria and sex-linked genetic markers extends to minor genome wide differences with some exceptions showing mixture between host strains is likely occurring in field populations.


Asunto(s)
Flujo Génico , Zea mays , Animales , Brasil , Humanos , Kenia , Spodoptera , Zea mays/genética
15.
J Appl Toxicol ; 41(2): 330-337, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-32767590

RESUMEN

Parabens (PBs) are compounds widely used in industry for food and personal care products as antimicrobials and preservatives. Their indiscriminate use has resulted in their detection in different ecosystems so that humans and other organisms are highly exposed. Methylparaben (MePB), compared with other PBs, is mostly detected in food, personal care and baby care products. PBs could be linked to the generation of hormonal disorders and fertility impairment since their recent classification as endocrine disruptors. The knowledge of the effects that MePB can exert is of great importance as, in terms of reproduction, information is limited. Therefore, the objective of the present study was to evaluate the effect of MePB on porcine oocyte viability and in vitro maturation (IVM), as well as to determine the lethal concentration at 50% (LC50 ) and the maturation inhibition concentration at 50% (MIC50 ). Oocytes were exposed to different MePB concentrations 0 (control), 50, 100, 500, 750 and 1000 µm during 44 h of IVM. Cytoplasmic alterations and reduced cumulus cell expansion were observed in oocytes exposed to MePB; however, viability was not affected. In addition, oocyte maturation decreased in a concentration-dependent manner after exposure to MePB. The estimated LC50 was 2028.38 µm, whereas MIC50 was 780.31 µm. To our knowledge, this is the first study that demonstrates that MePB altered porcine oocyte morphology, and caused a reduction in cumulus cell expansion, both of which resulted in decreased oocyte maturation. Therefore, MePB exposure may be one of the factors involved in fertility impairment in mammals, including that of humans.


Asunto(s)
Diferenciación Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Células Cultivadas/efectos de los fármacos , Oocitos/efectos de los fármacos , Oocitos/crecimiento & desarrollo , Parabenos/toxicidad , Animales , Humanos , Modelos Animales , Porcinos
16.
Proc Natl Acad Sci U S A ; 115(46): 11760-11765, 2018 11 13.
Artículo en Inglés | MEDLINE | ID: mdl-30381456

RESUMEN

Extensive planting of crops genetically engineered to produce insecticidal proteins from the bacterium Bacillus thuringiensis (Bt) has suppressed some major pests, reduced insecticide sprays, enhanced pest control by natural enemies, and increased grower profits. However, rapid evolution of resistance in pests is reducing these benefits. Better understanding of the genetic basis of resistance to Bt crops is urgently needed to monitor, delay, and counter pest resistance. We discovered that a point mutation in a previously unknown tetraspanin gene in the cotton bollworm (Helicoverpa armigera), a devastating global pest, confers dominant resistance to Cry1Ac, the sole Bt protein produced by transgenic cotton planted in China. We found the mutation using a genome-wide association study, followed by fine-scale genetic mapping and DNA sequence comparisons between resistant and susceptible strains. CRISPR/Cas9 knockout of the tetraspanin gene restored susceptibility to a resistant strain, whereas inserting the mutation conferred 125-fold resistance in a susceptible strain. DNA screening of moths captured from 23 field sites in six provinces of northern China revealed a 100-fold increase in the frequency of this mutation, from 0.001 in 2006 to 0.10 in 2016. The correspondence between the observed trajectory of the mutation and the trajectory predicted from simulation modeling shows that the dominance of the mutation accelerated adaptation. Proactive identification and tracking of the tetraspanin mutation demonstrate the potential for genomic analysis, gene editing, and molecular monitoring to improve management of resistance.


Asunto(s)
Resistencia a los Insecticidas/genética , Mariposas Nocturnas/genética , Tetraspaninas/genética , Animales , Animales Modificados Genéticamente/genética , Bacillus thuringiensis/genética , Proteínas Bacterianas/metabolismo , China , Evolución Molecular , Estudio de Asociación del Genoma Completo , Gossypium/genética , Insecticidas/metabolismo , Larva/genética , Larva/metabolismo , Control Biológico de Vectores , Plantas Modificadas Genéticamente/genética , Mutación Puntual/genética
17.
Int J Mol Sci ; 22(15)2021 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-34361073

RESUMEN

This study evaluated the immunonutritional effects caused by protease inhibitors from Avena sativa and Triticum durum to human macrophage-like cells. Macrophages were exposed (3 h) to extracts obtained from flours, and mitochondrial-associated oxygen consumption rates and inflammatory, metabolic, and proteome adaptations were quantified. Mass spectrometry 'm/z' signals of the extracts obtained from T. durum and A. sativa revealed molecular weights of 18-35 kDa and 16-22 kDa, respectively, for the compounds present at highest concentrations. Extracts from T. durum exhibited lower susceptibility to degradation by gastrointestinal enzymes than those from A. sativa: 9.5% vs 20.2%. Despite their different botanical origin, both extracts increased TLR4 expression. Metabolic protein levels were indicative of a decreased glycolytic to lactate flux in cell cultures upon stimulation with A. sativa extracts, which improved mitochondrial respiration in relation to those from T. durum. Principal components analysis confirmed relative similarities between immune-metabolic events triggered by immunonutritional ingredients in T. durum and A. sativa. Collectively, immunonutritional effects help to interpret the differences between both crops, worsening or improving, macrophage immune reactivity (tolerogenicity), and better control of inflammatory processes.


Asunto(s)
Avena/química , Macrófagos/inmunología , Macrófagos/metabolismo , Extractos Vegetales/farmacología , Inhibidores de Proteasas/farmacología , Proteoma/efectos de los fármacos , Triticum/química , Humanos , Macrófagos/efectos de los fármacos
18.
Biochem Biophys Res Commun ; 526(3): 706-712, 2020 06 04.
Artículo en Inglés | MEDLINE | ID: mdl-32253028

RESUMEN

Toxin-antitoxin systems are known to be involved in many bacterial functions that can lead to growth arrest and cell death in response to stress. Typically, toxin and antitoxin genes of type I systems are located in opposite strands, where the antitoxin is a small antisense RNA (sRNA). In the present work we show that the sRNA IsrA from Salmonella Typhimurium down-regulates the expression of its overlapping gene STM0294.1n. Multiple sequence alignment and comparative structure analysis indicated that STM0294.1n belongs to the SymE toxin superfamily, and the gene was renamed iasE (IsrA-overlapping gene with similarity to SymE). The iasE expression was induced in response to mitomycin C, an SOS-inducing agent; conversely, IsrA overexpression repressed the iasE expression even in the presence of mitomycin C. Accordingly, the inactivation of IsrA with an anti-IsrA RNA expressed in trans abrogated the repressive effect of IsrA on the iasE expression. On the other hand, iasE overexpression, as well as the blockage of the antisense IsrA function, negatively affected bacterial growth, arguing for a toxic effect of the iasE gene product. Besides, a bacterial lysate obtained from the iasE-overexpressing strain exhibited endoribonuclease activity, as determined by a fluorometric assay based on fluorescent reporter RNAs. Together, these results indicate that the IasE/IsrA pair of S. Typhimurium constitutes a functional type I toxin-antitoxin system.


Asunto(s)
Proteínas Bacterianas/genética , ARN sin Sentido/genética , ARN Bacteriano/genética , Respuesta SOS en Genética/genética , Salmonella typhimurium/genética , Secuencia de Aminoácidos , Antitoxinas/genética , Toxinas Bacterianas/genética , Endorribonucleasas/metabolismo , Regulación Bacteriana de la Expresión Génica , Mitomicina/metabolismo , Modelos Moleculares , Mutación , Sistemas de Lectura Abierta/genética , Conformación Proteica , Pliegue de Proteína
19.
Artículo en Inglés | MEDLINE | ID: mdl-32810593

RESUMEN

The intestine of marine fishes contributes to the ocean carbon cycle producing carbonate aggregates as part of the osmoregulatory process. Therefore, this study aimed to evaluate physiological adjustments of European sea bass (Dicentrarchus labrax) intestine to a higher pCO2 environment likely in the near future (~1700 µatm). At the whole-body level, hypercapnia for 5 weeks resulted in fish having a significantly diminished specific growth rate, condition factor and hepatosomatic index. An increase in plasma osmolality and HCO3- concentration was detected, paralleled by decreased metabolites concentrations. In the intestine, high seawater pCO2 was without effect on ouabain-sensitive ATPase activities, while Bafilomycin A1-sensitive ATPase activity significantly decreased in the anterior intestine. Anterior and mid intestine were mounted in Ussing chambers in order to measure bioelectrical parameters and bicarbonate secretion by pH-Stat ex-vivo. Hypercapnia induced a 2.3 and 2.8-fold increase in bicarbonate secretion rates in the anterior and mid intestine, respectively. In the intestinal fluid, HCO3- concentration increased 2.2-fold, and carbonate precipitates showed a 4.4-fold increase in response to hypercapnia, paralleled by a >3-fold increase of drinking and a >2-fold increase of intestinal volume at any given time. At the molecular level, hypercapnia elicited higher intestinal mRNA expression levels for atp6v1b (V-ATPase B subunit), slc4a4, slc26a3, and slc26a6, both in the anterior and mid intestine. As a whole, our results show that the intestine of sea bass responds to high seawater pCO2, a response that comes at a cost at the whole-body level with an impact in the fish specific growth rate, condition factor, and hepatosomatic index.


Asunto(s)
Ácidos/química , Lubina/fisiología , Concentración de Iones de Hidrógeno , Intestinos/fisiología , Océanos y Mares , Animales , Dióxido de Carbono/metabolismo
20.
Molecules ; 25(12)2020 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-32545715

RESUMEN

Botrytis cinerea is a ubiquitous necrotrophic filamentous fungal phytopathogen that lacks host specificity and can affect more than 1000 different plant species. In this work, we explored L1 [(E)-2-{[(2-aminopyridin-2-yl)imino]-methyl}-4,6-di-tert-butylphenol], a pyridine Schiff base harboring an intramolecular bond (IHB), regarding their antifungal activity against Botrytis cinerea. Moreover, we present a full characterization of the L1 by NMR and powder diffraction, as well as UV-vis, in the presence of previously untested different organic solvents. Complementary time-dependent density functional theory (TD-DFT) calculations were performed, and the noncovalent interaction (NCI) index was determined. Moreover, we obtained a scan-rate study on cyclic voltammetry of L1. Finally, we tested the antifungal activity of L1 against two strains of Botrytis cinerea (B05.10, a standard laboratory strain; and A1, a wild type strains isolated from Chilean blueberries). We found that L1 acts as an efficient antifungal agent against Botrytis cinerea at 26 °C, even better than the commercial antifungal agent fenhexamid. Although the antifungal activity was also observed at 4 °C, the effect was less pronounced. These results show the high versatility of this kind of pyridine Schiff bases in biological applications.


Asunto(s)
Antifúngicos , Botrytis/crecimiento & desarrollo , Piridinas , Antifúngicos/síntesis química , Antifúngicos/química , Antifúngicos/farmacología , Piridinas/síntesis química , Piridinas/química , Piridinas/farmacología
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