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1.
Ergonomics ; : 1-28, 2024 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-39189307

RESUMEN

This study investigates the perspectives of Canadian student and licenced pilots on general aviation pilot training and licencing practices. Employing a mixed-methods approach, this research critiques the reliance on flight hours as the sole competence metric and examines the alignment of existing practices with modern aviation's complexities. Findings reveal a divergence in opinions between novice and experienced pilots on flight hours' importance, with a consensus towards a competency-based evaluation model. The study identifies critical shortcomings in existing training practices, such as the challenge of integrating technology, fostering advanced skills, and efficiently utilising instructional resources. It suggests recommendations for regulatory enhancements, aiming to ensure training practices evolve in line with the changing requirements of aviation safety and technology. The conclusion calls for urgent reform, underlining the imperative for training adaptations that can prepare pilots to proficiently manage the complexities of contemporary airspace, thus safeguarding their proficiency and safety.


A survey conducted among Canadian student and licenced pilots to examine perspectives on general aviation pilot training and licencing practices uncovered critical shortcomings. The findings advocate for a strong preference for competency-based evaluations, urging reforms and regulatory improvements to ensure alignment with the evolving landscape of aviation safety and technological advancements.

2.
Clin Transl Radiat Oncol ; 46: 100782, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38694237

RESUMEN

Background and Purpose: After surgical resection of brain metastases (BM), radiotherapy (RT) is indicated. Postoperative stereotactic radiosurgery (SRS) reduces the risk of local progression and neurocognitive decline compared to whole brain radiotherapy (WBRT). Aside from the optimal dose and fractionation, little is known about the combination of systemic therapy and postoperative fractionated stereotactic radiotherapy (fSRT), especially regarding tumour control and toxicity. Methods: In this study, 105 patients receiving postoperative fSRT with 35 Gy in 7 fractions performed with Cyberknife were retrospectively reviewed. Overall survival (OS), local control (LC) and total intracranial brain control (TIBC) were analysed via Kaplan-Meier method. Cox proportional hazards models were used to identify prognostic factors. Results: Median follow-up was 20.8 months. One-year TIBC was 61.6% and one-year LC was 98.6%. Median OS was 28.7 (95%-CI: 16.9-40.5) months. In total, local progression (median time not reached) occurred in 2.0% and in 20.4% radiation-induced contrast enhancements (RICE) of the cavity (after median of 14.3 months) were diagnosed. Absence of extracranial metastases was identified as an independent prognostic factor for superior OS (p = <0.001) in multivariate analyses, while a higher Karnofsky performance score (KPS) was predictive for longer OS in univariate analysis (p = 0.041). Leptomeningeal disease (LMD) developed in 13% of patients. Conclusion: FSRT after surgical resection of BM is an effective and safe treatment approach with excellent local control and acceptable toxicity. Further prospective randomized trials are needed to establish standardized therapeutic guidelines.

3.
Hum Mol Genet ; 33(R1): R92-R99, 2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38779768

RESUMEN

The manipulation of animal mitochondrial genomes has long been a challenge due to the lack of an effective transformation method. With the discovery of specific gene editing enzymes, designed to target pathogenic mitochondrial DNA mutations (often heteroplasmic), the selective removal or modification of mutant variants has become a reality. Because mitochondria cannot efficiently import RNAs, CRISPR has not been the first choice for editing mitochondrial genes. However, the last few years witnessed an explosion in novel and optimized non-CRISPR approaches to promote double-strand breaks or base-edit of mtDNA in vivo. Engineered forms of specific nucleases and cytidine/adenine deaminases form the basis for these techniques. I will review the newest developments that constitute the current toolbox for animal mtDNA gene editing in vivo, bringing these approaches not only to the exploration of mitochondrial function, but also closer to clinical use.


Asunto(s)
ADN Mitocondrial , Edición Génica , Genoma Mitocondrial , Edición Génica/métodos , Animales , Genoma Mitocondrial/genética , Humanos , ADN Mitocondrial/genética , Sistemas CRISPR-Cas , Mitocondrias/genética , Mamíferos/genética , Mutación
4.
Environ Res ; 251(Pt 2): 118762, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38527720

RESUMEN

Treating high salt and high organic matter wastewater (HHW) generated during rapid socio-economic development is a significant challenge. This study aims to optimize a closed-cycle low-temperature evaporation (CCLE) system using mathematical modelling to be adapted to industrial applications. By using mathematical modelling and computational fluid dynamics (CFD), this study investigated the operating mechanism of the system under different operating conditions. Parametric analysis shows that increasing the compressor evaporation temperature and decreasing the condensation temperature is conducive to improving the performance of the heat pump unit, thereby increasing the wastewater treatment efficiency of the system and that a smaller heat transfer coil windward area is conducive to heat and mass transfer within the humidifier. The unique characteristics of the CCLE system are identified, and the wastewater treatment process under various operating conditions is explained. These findings may provide supporting information for the treatment of HHW by the CCLE system.


Asunto(s)
Hidrodinámica , Modelos Teóricos , Eliminación de Residuos Líquidos/métodos , Aguas Residuales/química , Frío
5.
Sci Total Environ ; 926: 171862, 2024 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-38527538

RESUMEN

Through the advancement of nanotechnology, agricultural and food systems are undergoing strategic enhancements, offering innovative solutions to complex problems. This scholarly essay thoroughly examines nanotechnological innovations and their implications within these critical industries. Traditional practices are undergoing radical transformation as nanomaterials emerge as novel agents in roles traditionally filled by fertilizers, pesticides, and biosensors. Micronutrient management and preservation techniques are further enhanced, indicating a shift towards more nutrient-dense and longevity-oriented food production. Nanoparticles (NPs), with their unique physicochemical properties, such as an extraordinary surface-to-volume ratio, find applications in healthcare, diagnostics, agriculture, and other fields. However, concerns about their potential overuse and bioaccumulation raise unanswered questions about their health effects. Molecule-to-molecule interactions and physicochemical dynamics create pathways through which nanoparticles cause toxicity. The combination of nanotechnology and environmental sustainability principles leads to the examination of green nanoparticle synthesis. The discourse extends to how nanomaterials penetrate biological systems, their applications, toxicological effects, and dissemination routes. Additionally, this examination delves into the ecological consequences of nanomaterial contamination in natural ecosystems. Employing robust risk assessment methodologies, including the risk allocation framework, is recommended to address potential dangers associated with nanotechnology integration. Establishing standardized, universally accepted guidelines for evaluating nanomaterial toxicity and protocols for nano-waste disposal is urged to ensure responsible stewardship of this transformative technology. In conclusion, the article summarizes global trends, persistent challenges, and emerging regulatory strategies shaping nanotechnology in agriculture and food science. Sustained, in-depth research is crucial to fully benefit from nanotechnology prospects for sustainable agriculture and food systems.


Asunto(s)
Nanoestructuras , Suelo , Conservación de los Recursos Naturales , Ecosistema , Análisis de Peligros y Puntos de Control Críticos , Agricultura/métodos , Nanotecnología/métodos , Plantas , Fertilizantes/análisis
6.
BMC Med Educ ; 24(1): 292, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38491363

RESUMEN

BACKGROUND: Narrative medicine demonstrated positive impact on empathy in medicine and nursing students. However, this pedagogical approach had not been evaluated in pharmacy education. This study sought to apply and evaluate the narrative medicine approach in extending empathy in Asian undergraduate pharmacy students. METHODS: Narrative medicine was applied through workshops which used narratives of people with different experiences and perspectives. First-year undergraduate pharmacy students who volunteered and attended these workshops formed the intervention group (N = 31) and the remaining first-year cohort formed the control group (N = 112). A sequential explanatory mixed methods approach was adopted in which quantitative methods were first used to measure impact on pharmacy students' empathy using the Jefferson Scale of Empathy- Health Professions Student (JSE-HPS), and qualitative methods (i.e. group interviews) were then used to assess pharmacy students' emotional responses to narratives, and the perspectives of pharmacy students and faculty of this pedagogical approach. RESULTS: There was no difference in JSE-HPS scores between intervention and control groups across baseline (i.e. upon matriculation), pre-intervention, and post-intervention timepoints. Pharmacy students in the intervention group had lower scores in Factor 3 ("Standing in People's Shoes") following the intervention. Five themes, guided by internal and external factors in cognition, emerged from the Group Interviews: (1) incongruence between students' motivation and faculty's perception, (2) learning context, (3) academic context, (4) cognitive system, and (5) affective system. Themes 1, 4 and 5 referred to internal factors such as students' motivation, perceived learnings, and feelings. Themes 2 and 3 referred to external factors including workshop materials, activities, content, and facilitation. CONCLUSION: This study is the first to demonstrate that pharmacy students engaged with the narrative medicine approach as narratives elicited emotional responses, exposed them to diverse perspectives, and deepened their appreciation of the importance of empathy and complexities of understanding patients' perspectives. Scaffolded educational interventions using narratives and real-life patient encounters, alongside longitudinal measurements of empathy, are necessary to bring about meaningful and sustained improvements in empathy.


Asunto(s)
Educación en Farmacia , Medicina Narrativa , Estudiantes de Medicina , Humanos , Singapur , Estudiantes de Medicina/psicología , Empatía , Personal de Salud
7.
Dev Sci ; 27(4): e13478, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38321588

RESUMEN

Childhood adversity can lead to cognitive deficits or enhancements, depending on many factors. Though progress has been made, two challenges prevent us from integrating and better understanding these patterns. First, studies commonly use and interpret raw performance differences, such as response times, which conflate different stages of cognitive processing. Second, most studies either isolate or aggregate abilities, obscuring the degree to which individual differences reflect task-general (shared) or task-specific (unique) processes. We addressed these challenges using Drift Diffusion Modeling (DDM) and structural equation modeling (SEM). Leveraging a large, representative sample of 9-10 year-olds from the Adolescent Brain Cognitive Development (ABCD) study, we examined how two forms of adversity-material deprivation and household threat-were associated with performance on tasks measuring processing speed, inhibition, attention shifting, and mental rotation. Using DDM, we decomposed performance on each task into three distinct stages of processing: speed of information uptake, response caution, and stimulus encoding/response execution. Using SEM, we isolated task-general and task-specific variances in each processing stage and estimated their associations with the two forms of adversity. Youth with more exposure to household threat (but not material deprivation) showed slower task-general processing speed, but showed intact task-specific abilities. In addition, youth with more exposure to household threat tended to respond more cautiously in general. These findings suggest that traditional assessments might overestimate the extent to which childhood adversity reduces specific abilities. By combining DDM and SEM approaches, we can develop a more nuanced understanding of how adversity affects different aspects of youth's cognitive performance. RESEARCH HIGHLIGHT: To understand how childhood adversity shapes cognitive abilities, the field needs analytical approaches that can jointly document and explain patterns of lowered and enhanced performance. Using Drift Diffusion Modeling and Structural Equation Modeling, we analyzed associations between adversity and processing speed, inhibition, attention shifting, and mental rotation. Household threat, but not material deprivation, was mostly associated with slower task-general processing speed and more response caution. In contrast, task-specific abilities were largely intact. Researchers might overestimate the impact of childhood adversity on specific abilities and underestimate the impact on general processing speed and response caution using traditional measures.


Asunto(s)
Cognición , Humanos , Niño , Femenino , Masculino , Cognición/fisiología , Disfunción Cognitiva , Adolescente , Experiencias Adversas de la Infancia , Tiempo de Reacción/fisiología , Atención/fisiología , Pruebas Neuropsicológicas
8.
Chemistry ; 30(18): e202303570, 2024 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-38018494

RESUMEN

NMR spectroscopy techniques can provide important information about protein-ligand interactions. Here we tested an NMR approach which relies on the measurement of paramagnetic relaxation enhancements (PREs) arising from analogous cationic, anionic or neutral soluble nitroxide molecules, which distribute around the protein-ligand complex depending on near-surface electrostatic potentials. We applied this approach to two protein-ligand systems, interleukin-8 interacting with highly charged glycosaminoglycans and the SH2 domain of Grb2 interacting with less charged phospho-tyrosine tripeptides. The electrostatic potential around interleukin-8 and its changes upon binding of glycosaminoglycans could be derived from the PRE data and confirmed by theoretical predictions from Poisson-Boltzmann calculations. The ligand influence on the PREs and NMR-derived electrostatic potentials of Grb2 SH2 was localized to a narrow protein region which allowed the localization of the peptide binding pocket. Our analysis suggests that experiments with nitroxide cosolutes can be useful for investigating protein-ligand electrostatic interactions and mapping ligand binding sites.


Asunto(s)
Glicosaminoglicanos , Interleucina-8 , Óxidos de Nitrógeno , Ligandos , Sitios de Unión
9.
Small ; 20(15): e2306753, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37994254

RESUMEN

Photosensitive supercapacitors incorporate light-sensitive materials on capacitive electrodes, enabling solar energy conversion and storage in one device. In this study, heterogeneous structures of rod-shaped ZnO decorated with Ce2S3 nanoparticles on nickel foam (ZnO@Ce2S3/NF) are synthesized using a two-step hydrothermal method as photosensitive supercapacitor electrodes for capacitance enhancement under visible light. The formation of ZnO@Ce2S3 heterogeneous structures is confirmed using various structural characterization techniques. The area-specific capacitance of the ZnO@Ce2S3/NF composite electrode increased from 1738.1 to 1844.0 mF cm-2 after illumination under a current density of 5 mA cm-2, which is 2.4 and 2.8 times higher than that of ZnO and Ce2S3 electrodes under similar conditions, respectively, indicating the remarkable light-induced capacitance enhancement performance. The ZnO@Ce2S3/NF electrode also exhibits a higher photocurrent and photovoltage than the two single electrodes, demonstrating its excellent photosensitivity. The improved capacitance performance and photosensitivity under illumination are attributed to the well-constructed energy-level structure, which stimulates the flow of photogenerated electrons from the outer circuit and the involvement of photogenerated holes in the resulting surface-controlled capacitance. In addition, the assembled ZnO@Ce2S3/NF-based hybrid supercapacitor exhibits a great energy density of 145.0 mWh cm-2 under illumination. This study provides a novel strategy for the development of high-performance solar energy conversion/storage devices.

10.
Expert Rev Med Devices ; 20(12): 1087-1103, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37934873

RESUMEN

INTRODUCTION: Colorectal cancer (CRC) is the third most common malignancy and second leading cause of cancer-related mortality in the world. Adenoma detection rate (ADR), a quality indicator for colonoscopy, has gained prominence as it is inversely related to CRC incidence and mortality. As such, recent efforts have focused on developing novel colonoscopy devices and technologies to improve ADR. AREAS COVERED: The main objective of this paper is to provide an overview of advancements in the fields of colonoscopy mechanical attachments, artificial intelligence-assisted colonoscopy, and colonoscopy optical enhancements with respect to ADR. We accomplished this by performing a comprehensive search of multiple electronic databases from inception to September 2023. This review is intended to be an introduction to colonoscopy devices and technologies. EXPERT OPINION: Numerous mechanical attachments and optical enhancements have been developed that have the potential to improve ADR and AI has gone from being an inaccessible concept to a feasible means for improving ADR. While these advances are exciting and portend a change in what will be considered standard colonoscopy, they continue to require refinement. Future studies should focus on combining modalities to further improve ADR and exploring the use of these technologies in other facets of colonoscopy.


Asunto(s)
Adenoma , Neoplasias Colorrectales , Humanos , Inteligencia Artificial , Colonoscopía , Adenoma/diagnóstico , Adenoma/epidemiología , Incidencia , Tecnología , Neoplasias Colorrectales/diagnóstico , Detección Precoz del Cáncer/métodos
11.
Adv Sci (Weinh) ; 10(33): e2302922, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37863818

RESUMEN

Hybridizing single-walled carbon nanotubes (SWCNTs) with π-conjugated organic small molecules (π-OSMs) offers a promising approach for producing high-performance thermoelectric (TE) materials through the facile optimization of the molecular geometry and energy levels of π-OSMs. Designing a twisted molecular structure for the π-OSM with the highest occupied molecular orbital energy level comparable to the valence band of SWCNTs enables effective energy filtering between the two materials. The SWCNTs/twisted π-OSM hybrid exhibits a high Seebeck coefficient of 110.4 ± 2.6 µV K-1 , leading to a significantly improved power factor of 2,136 µW m-1 K-2 , which is 2.6 times higher than that of SWCNTs. Moreover, a maximum figure of merit over 0.13 at room temperature is achieved via the efficient TE transport of the SWCNTs/twisted π-OSM hybrid. The study highlights the promising potential of optimizing molecular engineering of π-OSMs for hybridization with SWCNTs to create next-generation, efficient TE materials.

12.
Sensors (Basel) ; 23(13)2023 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-37448064

RESUMEN

Infrared small-target enhancement in complex contexts is one of the key technologies for infrared search and tracking systems. The effect of enhancement directly determines the reliability of the monitoring equipment. To address the problem of the low signal-to-noise ratio of small infrared moving targets in complex backgrounds and the poor effect of traditional enhancement algorithms, an accurate enhancement method for small infrared moving targets based on two-channel information is proposed. For a single frame, a modified curvature filter is used in the A channel to weaken the background while an improved PM model is used to enhance the target, and a modified band-pass filter is used in the B channel for coarse enhancement followed by a local contrast algorithm for fine enhancement, based on which a weighted superposition algorithm is used to extract a single-frame candidate target. The results of the experimental data analysis prove that the method has a good enhancement effect and robustness for small IR motion target enhancement in complex backgrounds, and it outperforms other advanced algorithms by about 43.7% in ROC.


Asunto(s)
Algoritmos , Aumento de la Imagen , Reproducibilidad de los Resultados , Aumento de la Imagen/métodos , Relación Señal-Ruido
13.
Front Physiol ; 14: 1173991, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37485066

RESUMEN

Purpose: This study aimed to investigate the effect of re-warm-up (RWUP) activities consisting of three sets of 15-m sprints with weighted vests on 20-m sprint performance after the break. Methods: Using a randomized, and counterbalanced cross-over design, twenty U15 elite soccer players performed four RWUP trials which consisted of 15-min of passive rest (control: CONT), 3 × 15-m sprint (RW0%), sprinting with a vest-loaded at 5% of body-mass (BM) (RW5%), sprinting with a 10% BM vest (RW10%). The 3-min RWUP protocols started 10-min after the commencement of the 15-min between-halves break and concluded 2-min before its end. During each testing session, the participant's RPE scores, and 20-m sprint performance were registered before the first half, and at the end of the break of the simulated match-play. Results: Significant time effects [F (1.72) = 54.37, d = 1.88, p < 0.001; F (1.72) = 9.07, d = 0.77, p = 0.003], and condition effects [F (3.72) = 11.81, d = 1.53, p < 0.001; F (3.72) = 7.36, d = 1.21, p = 0.003] were observed for RPE scores and 20-m sprint performance, respectively. Significant condition-by-time interactions were found for RPE scores (p < 0.003, d = 0.54), and 20-m sprint performance (p < 0.002, d = 0.70). Contrast analysis showed significantly higher RPE scores (p < 0.001, d = 1.55), and improved 20-m sprint performance (p = 0.0004, d = 1.19) in the RW10% condition compared to all other conditions. Conclusion: Sprinting for 3-min with a 10% body-mass vest resulted in the highest RPE scores and the most substantial enhancements in 20-m sprint performance. Young elite soccer players should incorporate 10% body-mass weighted vests in their re-warm-ups to boost post-break sprint performance.

14.
Appl Radiat Isot ; 199: 110863, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37276661

RESUMEN

In the present work, the Doppler Shift Attenuation method (DSAM) was used to analyze the observed lineshapes of transitions from excited states in 45Sc, populated in the reaction 36Ar + 12C at a beam energy of 145 MeV. The interpretation and comparison of the experimental results have been performed with large-scale shell model calculations, involving different interactions like: GX1A, GX1J, FPD6, KB3 and ZBM2. KB3 and FPD6 (present work) interactions in the negative parity states, and in positive parity states ZBM2 are most pre-eminent in reproducing the results, due to the large configuration space describing strong collective effects. Furthermore, the present work also looks at the details of the shell model helping in improving the understanding for the occupancy of orbitals. The present investigation suggests the observation of stronger collectivity for positive parity states over negative parity states with predicted enhanced collectivity of states in 45Sc nucleus.

15.
J Imaging ; 9(6)2023 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-37367461

RESUMEN

The Posidonia oceanica meadows represent a fundamental biological indicator for the assessment of the marine ecosystem's state of health. They also play an essential role in the conservation of coastal morphology. The composition, extent, and structure of the meadows are conditioned by the biological characteristics of the plant itself and by the environmental setting, considering the type and nature of the substrate, the geomorphology of the seabed, the hydrodynamics, the depth, the light availability, the sedimentation speed, etc. In this work, we present a methodology for the effective monitoring and mapping of the Posidonia oceanica meadows by means of underwater photogrammetry. To reduce the effect of environmental factors on the underwater images (e.g., the bluish or greenish effects), the workflow is enhanced through the application of two different algorithms. The 3D point cloud obtained using the restored images allowed for a better categorization of a wider area than the one made using the original image elaboration. Therefore, this work aims at presenting a photogrammetric approach for the rapid and reliable characterization of the seabed, with particular reference to the Posidonia coverage.

16.
Front Chem ; 11: 1176746, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37179775

RESUMEN

Organophosphorus esters fulfil many industrial, agricultural, and household roles. Nature has deployed phosphates and their related anhydrides as energy carriers and reservoirs, as constituents of genetic materials in the form of DNA and RNA, and as intermediates in key biochemical conversions. The transfer of the phosphoryl (PO3) group is thus a ubiquitous biological process that is involved in a variety of transformations at the cellular level such as bioenergy and signals transductions. Significant attention has been paid in the last seven decades to understanding the mechanisms of uncatalyzed (solution) chemistry of the phospho group transfer because of the notion that enzymes convert the dissociative transition state structures in the uncatalyzed reactions into associative ones in the biological processes. In this regard, it has also been proposed that the rate enhancements enacted by enzymes result from the desolvation of the ground state in the hydrophobic active site environments, although theoretical calculations seem to disagree with this position. As a result, some attention has been paid to the study of the effects of solvent change, from water to less polar solvents, in uncatalyzed phospho transfer reactions. Such changes have consequences on the stabilities of the ground and the transition states of reactions which affect reactivities and, sometimes, the mechanisms of reactions. This review seeks to collate and evaluate what is known about solvent effects in this domain, especially their effects on rates of reactions of different classes of organophosphorus esters. The outcome of this exercise shows that a systematized study of solvent effects needs to be undertaken to fully understand the physical organic chemistry of the transfer of phosphates and related molecules from aqueous to substantially hydrophobic environments, since significant knowledge gaps exist.

17.
Dermatol Clin ; 41(3): 547-555, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37236721

RESUMEN

Skin of color in dermatology encompasses individuals of various ethnic backgrounds including Black or those of African descent, Hispanic or Latino, Asian, Native American, Pacific Islander, and those of mixed ethnicities. Because these populations continue to expand, more patients of color (POC) are seeking out cosmetic enhancements and treatments. Aside from cosmeceuticals, nonsurgical cosmetic rejuvenation options, such laser and light-based treatments, neurotoxins, soft tissue augmentation, and more recently body contouring and skin tightening, are becoming increasingly popular worldwide. This article examines risks of cosmetic enhancement procedures in POC and best practices to prevent adverse events.


Asunto(s)
Técnicas Cosméticas , Envejecimiento de la Piel , Humanos , Técnicas Cosméticas/efectos adversos , Neurotoxinas , Piel , Minorías Étnicas y Raciales
18.
Int J Mol Sci ; 24(10)2023 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-37240203

RESUMEN

The present study presents the tertiary assembly of a POM, peptide, and biogenic amine, which is a concept to construct new hybrid bio-inorganic materials for antibacterial applications and will help to promote the development of antivirus agents in the future. To achieve this, a Eu-containing polyoxometalate (EuW10) was first co-assembled with a biogenic amine of spermine (Spm), which improved both the luminescence and antibacterial effect of EuW10. Further introduction of a basic peptide from HPV E6, GL-22, induced more extensive enhancements, both of them being attributed to the cooperation and synergistic effects between the constituents, particularly the adaptive responses of assembly to the bacterial microenvironment (BME). Further intrinsic mechanism investigations revealed in detail that the encapsulation of EuW10 in Spm and further GL-22 enhanced the uptake abilities of EuW10 in bacteria, which further improved the ROS generation in BME via the abundant H2O2 involved there and significantly promoted the antibacterial effects.


Asunto(s)
Peroxidasa , Compuestos de Tungsteno , Compuestos de Tungsteno/farmacología , Peróxido de Hidrógeno , Péptidos , Colorantes , Antibacterianos/farmacología
19.
Int J Mol Sci ; 24(9)2023 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-37175539

RESUMEN

Nuclear magnetic resonance (NMR) spectroscopy is a powerful method for studying the structure and dynamics of proteins in their native state. For high-resolution NMR structure determination, the collection of a rich restraint dataset is necessary. This can be difficult to achieve for proteins with high molecular weight or a complex architecture. Computational modeling techniques can complement sparse NMR datasets (<1 restraint per residue) with additional structural information to elucidate protein structures in these difficult cases. The Rosetta software for protein structure modeling and design is used by structural biologists for structure determination tasks in which limited experimental data is available. This review gives an overview of the computational protocols available in the Rosetta framework for modeling protein structures from NMR data. We explain the computational algorithms used for the integration of different NMR data types in Rosetta. We also highlight new developments, including modeling tools for data from paramagnetic NMR and hydrogen-deuterium exchange, as well as chemical shifts in CS-Rosetta. Furthermore, strategies are discussed to complement and improve structure predictions made by the current state-of-the-art AlphaFold2 program using NMR-guided Rosetta modeling.


Asunto(s)
Imagen por Resonancia Magnética , Proteínas , Modelos Moleculares , Proteínas/química , Espectroscopía de Resonancia Magnética/métodos , Programas Informáticos , Resonancia Magnética Nuclear Biomolecular/métodos , Conformación Proteica
20.
Heliyon ; 9(3): e14151, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36950629

RESUMEN

Equatorial Spread F (ESF), is a manifestation linked to Atmospheric Gravity Waves (AGW). There have not been many studies to ascertain the extensive relationship between the occurrence of AGW and the occurrence of ESF. To evaluate the extent of their relationship, this study used data obtained with the aid of a satellite-borne Atmospheric Infrared Sounder (AIRS) and ionograms obtained using a Digisonde Portable Sounder (DPS-4) located at Jicamarca (geog. Lat. 11.950 ᵒS, long. 76.867 ᵒW and geomagnetic Lat. 2.27 ᵒS, Long. 4.15 ᵒW; Dip 2 ᵒN) during the year 2016. The results also suggest that whenever AGW, under the control of tidal winds, propagates into F-region heights such that both AGW and tidal wind structures act together, it could have great potential at influencing plasma instability growth rate. The result further shows that when AGW has a long enough wavelength to reach the F-region, it tends to influence the factors responsible for the occurrence of the Mixed Spread-F (MSF) type of ESF. MSF is observed to be predominant in occurrence whenever AGW and ESF occur simultaneously compared to the other two types of ESF. The coefficient of correlation between AGW and MSF ranged between 0.1 and 0.5, while for Range Spread-F and Frequency Spread-F, it ranged between ± 0.2. These levels of correlations show that AGW does not directly trigger ESF. The range of the correlation coefficient between AGW and MSF however tends to support the suggestion that AGW occurrence is capable of influencing the factors responsible for a type of ESF occurrence rather than triggering ESF occurrence altogether.

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