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1.
Proc Natl Acad Sci U S A ; 121(11): e2307801120, 2024 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-38437539

RESUMEN

Adding a cationic helper lipid to a lipid nanoparticle (LNP) can increase lung delivery and decrease liver delivery. However, it remains unclear whether charge-dependent tropism is universal or, alternatively, whether it depends on the component that is charged. Here, we report evidence that cationic cholesterol-dependent tropism can differ from cationic helper lipid-dependent tropism. By testing how 196 LNPs delivered mRNA to 22 cell types, we found that charged cholesterols led to a different lung:liver delivery ratio than charged helper lipids. We also found that combining cationic cholesterol with a cationic helper lipid led to mRNA delivery in the heart as well as several lung cell types, including stem cell-like populations. These data highlight the utility of exploring charge-dependent LNP tropism.


Asunto(s)
Hígado , Células Madre , Corazón , Cationes , Colesterol , ARN Mensajero
2.
Nucleic Acids Res ; 2024 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-38994567

RESUMEN

Immune responses need to be regulated to prevent autoimmunity. CRISPR-Cas systems provide adaptive immunity in prokaryotes through the acquisition of short DNA sequences from invading viruses (bacteriophages), known as spacers. Spacers are inserted into the CRISPR locus and serve as templates for the transcription of guides used by RNA-guided nucleases to recognize complementary nucleic acids of the invaders and start the CRISPR immune response. In type II-A CRISPR systems, Cas9 uses the guide RNA to cleave target DNA sequences in the genome of infecting phages, and the tracrRNA to bind the promoter of cas genes and repress their transcription. We previously isolated a Cas9 mutant carrying the I473F substitution that increased the frequency of spacer acquisition by 2-3 orders of magnitude, leading to a fitness cost due to higher levels of autoimmunity. Here, we investigated the molecular basis underlying these findings. We found that the I473F mutation decreases the association of Cas9 to tracrRNA, limiting its repressor function, leading to high levels of expression of cas genes, which in turn increase the strength of the type II-A CRISPR-Cas immune response. We obtained similar results for a related type II-A system, and therefore our findings highlight the importance of the interaction between Cas9 and its tracrRNA cofactor in tuning the immune response to balanced levels that enable phage defense but avoid autoimmunity.

3.
Int Microbiol ; 2024 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-38977514

RESUMEN

This study explored the extracellular metabolomic responses of three different Salmonella enterica serotype Typhimurium (S. Typhimurium) strains-ATCC 13311 (STy1), NCCP 16964 (STy4), and NCCP 16958 (STy8)-cultured at refrigeration temperatures. The objective was to identify the survival mechanisms of S. Typhimurium under cold stress by analyzing variations in their metabolomic profiles. Qualitative and quantitative assessments identified significant metabolite alterations on day 6, marking a critical inflection point. Key metabolites such as trehalose, proline, glycerol, and tryptophan were notably upregulated in response to cold stress. Through multivariate analyses, the strains were distinguished using three metabolites-4-aminobutyrate, ethanol, and uridine-as potential biomarkers, underscoring distinct metabolic responses to refrigeration. Specifically, STy1 exhibited unique adaptive capabilities through enhanced metabolism of betaine and 4-aminobutyrate. These findings highlight the variability in adaptive strategies among S. Typhimurium strains, suggesting that certain strains may possess more robust metabolic pathways for enhancing survival in refrigerated conditions.

4.
Appl Microbiol Biotechnol ; 108(1): 86, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38189951

RESUMEN

Despite the discovery of several bacteria capable of interacting with polymers, the activity of the natural bacterial isolates is limited. Furthermore, there is a lack of knowledge regarding the development of bioprocesses for polyethylene (PE) degradation. Here, we report a bioprocess using pseudo-resting cells for efficient degradation of PE. The bacterial strain Acinetobacter nosocomialis was isolated from PE-containing landfills and characterized using low-density PE (LDPE) surface oxidation when incubated with LDPE. We optimized culture conditions to generate catalytic pseudo-resting cells of A. nosocomialis that are capable of degrading LDPE films in a bioreactor. After 28 days of bioreactor operation using pseudo-resting cells of A. nosocomialis, we observed the formation of holes on the PE film (39 holes per 217 cm2, a maximum diameter of 1440 µm). This study highlights the potential of bacteria as biocatalysts for the development of PE degradation processes. KEY POINTS: • New bioprocess has been proposed to degrade polyethylene (PE). • Process with pseudo-resting cells results in the formation of holes in PE film. • We demonstrated PE degradation using A. nosocomialis as a biocatalyst.


Asunto(s)
Acinetobacter , Polietileno , Reactores Biológicos , Catálisis
5.
Appetite ; 200: 107555, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-38878902

RESUMEN

This study used mixed methods to explore the impact of front-of-package health claims and bonus pack messages on consumer evaluations. First, a comprehensive audit of cereal box packages at the world's largest retailer examined how these messages are presented in practice. It was found that negative claims are more frequent and positive claims are less frequent on products with a bonus pack message compared to those without. A subsequent experiment investigated how combinations of health claims and bonus pack messages influence consumer evaluations. It also found that health claims significantly influenced consumer preferences, while bonus pack messages diminished perceptions of food healthiness but increased perceived value. Pairing positive health claims with bonus pack messages, such as "Family Size," improved perceptions of healthiness. Moreover, positive health claims made products seem of lower value, whereas negative health claims did not affect perceived value. Health claims negatively affected value perceptions, even when paired with bonus pack messages like "Large Size." However, the negative effect of health claims on tastiness perceptions was mitigated with "Large Size". The study underscores the complexity of consumer decision-making, and offer insights for food marketers, emphasizing the need of a strategic approach in crafting health-related messaging and promotional strategies for product packaging.


Asunto(s)
Conducta de Elección , Comportamiento del Consumidor , Etiquetado de Alimentos , Embalaje de Alimentos , Preferencias Alimentarias , Humanos , Femenino , Masculino , Adulto , Etiquetado de Alimentos/métodos , Preferencias Alimentarias/psicología , Embalaje de Alimentos/métodos , Adulto Joven , Persona de Mediana Edad , Promoción de la Salud/métodos , Percepción , Adolescente , Dieta Saludable/psicología , Gusto
6.
J Adv Nurs ; 80(8): 3103-3118, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38197503

RESUMEN

AIM: To describe uncertainty in surrogate decision-making regarding end-of-life care for people with dementia using Mishel's reconceptualized uncertainty in illness theory. DESIGN: Integrative literature review using Whittemore and Knafl's approach. DATA SOURCES: PubMed, CINAHL, EMBASE, Scopus and Web of Science were searched using terms such as uncertainty/unpredictability, decision-making/advance care planning/end-of-life care planning, surrogate/family/caregiver/proxy and dementia. The search was initially conducted on 28 September 2021 and updated on 31 July 2023. REVIEW METHODS: Through systematic screening, 20 research articles were included in the analysis. Content related to uncertainty in surrogate decision-making regarding end-of-life care was extracted and analysed, focusing on the reconceptualized uncertainty in illness theory. RESULTS: First, surrogate uncertainty exists in various areas of surrogate decision-making regarding end-of-life care. Second, antecedents of surrogate uncertainty include numerous intrinsic and extrinsic factors. Third, surrogates exhibited some negative psychological responses to uncertainty but continually processed and structured their uncertainty through certain approaches, leading them to grow as decision-makers. Finally, research-based evidence on surrogates' processing of uncertainty and shifts to new life perspectives remains limited. CONCLUSION: Surrogates' uncertainty in decision-making regarding end-of-life care for people with dementia is well characterized using the reconceptualized uncertainty in illness theory. Healthcare providers should help surrogates manage their uncertainty in surrogate decision-making more constructively throughout the dementia trajectory. IMPLICATIONS FOR THE PROFESSION AND/OR PATIENT CARE: The findings highlight the importance of assessing how surrogates process uncertainty and gauging how to help them process uncertainty and transition to new life perspectives. IMPACT: This review contributes to healthcare professionals' understanding of surrogates' uncertainty in end-of-life care planning for people with dementia, especially what they are uncertain about, what influences their uncertainty and how they process it. REPORTING METHOD: This study adheres to the PRISMA reporting guidelines. PATIENT OR PUBLIC CONTRIBUTION: No patient or public contribution.


Asunto(s)
Toma de Decisiones , Demencia , Apoderado , Cuidado Terminal , Humanos , Demencia/psicología , Demencia/enfermería , Demencia/terapia , Cuidado Terminal/psicología , Incertidumbre , Apoderado/psicología , Planificación Anticipada de Atención , Anciano , Cuidadores/psicología , Masculino , Femenino , Anciano de 80 o más Años
7.
J Clin Nurs ; 2024 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-39072827

RESUMEN

AIMS: To describe and compare nurses' awareness of, attitudes toward, and participation in advance care planning, as well as related facilitators and challenges, in four types of healthcare settings. DESIGN: A cross-sectional descriptive study. METHODS: Four hundred and ninety-eight registered nurses from tertiary, secondary and primary healthcare institutions, along with long-term care centres in South Korea, participated in an investigator-developed online survey. The collected data were analysed using descriptive statistics, chi-squared test, one-way ANOVA, and binary logistic regression. RESULTS: Participants were on average 30.6 ± 7.3 years old, mostly female (95.4%), employed as staff nurses (95.4%), held bachelor's degrees or higher (84.1%), and had worked for less than 5 years at their current institutions (69.7%). Overall, 49% of the participants were familiar with advance care planning. While most participants supported nurse involvement in advance care planning with patients and surrogates, fewer were willing to engage or recommend it. Less than half were actively engaged in advance care planning practices. A notable challenge was the lack of time due to excessive workload. Compared to those from tertiary healthcare institutions, participants from secondary and primary healthcare institutions and long-term care centres were less likely to be aware of advance care planning. Participants from secondary and primary healthcare institutions had lower odds of checking for the presence of advance directives and the physician orders for life-sustaining treatment. CONCLUSION: Nurses demonstrated low awareness and participation in advance care planning. Nurses' insufficient time and competency to conduct advance care planning in their practice should be addressed. IMPLICATIONS FOR THE PROFESSION AND/OR PATIENT CARE: Educational programs, initiatives (e.g. guidelines, position statements) and legal and policy-level efforts (e.g. nurse staffing, role clarification, reimbursement) are crucial to incorporate advance care planning into routine nursing practice. IMPACT: What problem did the study address? Nurses play an important role in advance care planning; however, limited is understood about their readiness and involvement in such practices. What were the main findings? Nurses' awareness of advance care planning practices and their participation in such practices is low across care settings. Although nurses have a positive attitude toward advance care planning, there are challenges (e.g. insufficient time to conduct advance care planning discussions and lack of relevant knowledge and skills) that impede their participation in practice. Where and on whom will the research have an impact? This study may serve as a foundation for nursing societies in countries, where advance care planning is emerging, to discuss strategies to increase nurses' competency in advance care planning and promote their participation in the practice. REPORTING METHOD: The STROBE checklist was followed. PATIENT OR PUBLIC CONTRIBUTION: No patient or public contribution.

8.
J Psychosoc Nurs Ment Health Serv ; 62(7): 11-15, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38976856

RESUMEN

The mental health needs of Asian American older adults are complex and multifaceted. Despite their rich diversity, Asian American older adults face significant challenges, including mental health stigma, cultural stress, limited English proficiency, and historical trauma. In addition, the coronavirus disease 2019 pandemic reignited preexisting anti-Asian attitudes of hostility, discrimination, blame, and scapegoating. The historical context of Asian immigration to the United States, impact of race-based discrimination, and recent resurgence of anti-Asian hate crimes impact mental health in Asian American older adults. Thus, there is a need for a culturally sensitive and competent mental health care workforce, culturally tailored interventions, and family involvement. In the context of research and policy, it is critical to prioritize increased funding and research focus on culturally tailored instrument development, interventions, and policy initiatives informed by recent findings to safeguard this population from hate crimes and discrimination. [Journal of Psychosocial Nursing and Mental Health Services, 62(7), 11-15.].


Asunto(s)
Asiático , COVID-19 , Estigma Social , Humanos , Asiático/psicología , Asiático/estadística & datos numéricos , Anciano , Estados Unidos , COVID-19/etnología , COVID-19/psicología , Servicios de Salud Mental , Salud Mental , Racismo/psicología , SARS-CoV-2 , Necesidades y Demandas de Servicios de Salud
9.
Curr Issues Mol Biol ; 45(12): 10159-10178, 2023 Dec 16.
Artículo en Inglés | MEDLINE | ID: mdl-38132480

RESUMEN

The process of skin aging is currently recognized as a disease, and extracellular vesicles (EVs) are being used to care for it. While various EVs are present in the market, there is a growing need for research on improving skin conditions through microbial and plant-derived EVs. Edelweiss is a medicinal plant and is currently an endangered species. Callus culture is a method used to protect rare medicinal plants, and recently, research on EVs using callus culture has been underway. In this study, the researchers used LED light to increase the productivity of Edelweiss EVs and confirmed that productivity was enhanced by LED exposure. Additionally, improvements in skin anti-aging indicators were observed. Notably, M-LED significantly elevated callus fresh and dry weight, with a DW/FW ratio of 4.11%, indicating enhanced proliferation. Furthermore, M-LED boosted secondary metabolite production, including a 20% increase in total flavonoids and phenolics. The study explores the influence of M-LED on EV production, revealing a 2.6-fold increase in concentration compared to darkness. This effect is consistent across different plant species (Centella asiatica, Panax ginseng), demonstrating the universality of the phenomenon. M-LED-treated EVs exhibit a concentration-dependent inhibition of reactive oxygen species (ROS) production, surpassing dark-cultured EVs. Extracellular melanin content analysis reveals M-LED-cultured EVs' efficacy in reducing melanin production. Additionally, the expression of key skin proteins (FLG, AQP3, COL1) is significantly higher in fibroblasts treated with M-LED-cultured EVs. These results are expected to provide valuable insights into research on improving the productivity of plant-derived EVs and enhancing skin treatment using plant-derived EVs.

10.
J Med Virol ; 95(12): e29329, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-38140877

RESUMEN

Developing new antibody assays for emerging SARS-CoV-2 variants is challenging. SARS-CoV-2 surrogate virus neutralization tests (sVNT) targeting Omicron BA.1 and BA.5 have been devised, but their performance needs to be validated in comparison with quantitative immunoassays. First, using 1749 PRNT-positive sera, we noticed that log-transformed optical density (OD) ratio of wild-type (WT) sVNT exhibited better titer-correlation with plaque reduction neutralization test (PRNT) than % inhibition value. Second, we tried 798 dilutional titration tests with 103 sera, but nonlinear correlation between OD ratio and antibody concentration limited titration of sVNT. Third, the titer-correlations of two sVNT kits for BA.1 and two quantitative immunoassays for WT were evaluated with BA.1 and BA.5 PRNT. All tested kits exhibited a linear correlation with PRNT titers, but the sVNT kits exhibited high false-negative rates (cPass-BA.1 kit, 45.4% for BA.1 and 44.2% for BA.5; STANDARD F-BA.1 kit, 1.9% for BA.1 and 2.2% for BA.5), while quantitative immunoassays showed 100% sensitivity. Linear mixed-effects model suggested superior titer-correlation with PRNT for quantitative immunoassays compared to sVNT kits. Taken together, the use of quantitative immunoassays for WT, rather than rapid development of new kits, would be practical for predicting neutralizing activities against emerging new variants.


Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , Pruebas de Neutralización , SARS-CoV-2/genética , COVID-19/diagnóstico , Inmunoensayo , Anticuerpos Neutralizantes , Anticuerpos Antivirales
11.
Molecules ; 28(24)2023 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-38138458

RESUMEN

The purpose of this study was to evaluate the physicochemical properties of whey protein hydrolysate and determine changes in absorption rate due to enzymatic hydrolysis. The molecular weight distribution analysis of whey protein concentrate (WPC) and low-molecule whey protein hydrolysate (LMWPH) using the Superdex G-75 column revealed that LMWPH is composed of peptides smaller than those in WPC. Fourier-transform infrared spectroscopy indicated differences in peak positions between WPC and LMWPH, suggesting hydrolysis-mediated changes in secondary structures. Moreover, LMWPH exhibited higher thermal stability and faster intestinal permeation than WPC. Additionally, oral LMWPH administration increased serum protein content at 20 min, whereas WPC gradually increased serum protein content after 40 min. Although the total amount of WPC and LMWPH absorption was similar, LMWPH absorption rate was higher. Collectively, LMWPH, a hydrolysate of WPC, has distinct physicochemical properties and enhanced absorptive characteristics. Taken together, LMWPH is composed of low-molecular-weight peptides with low antigenicity and has improved absorption compared to WPC. Therefore, LMWPH can be used as a protein source with high bioavailability in the development of functional materials.


Asunto(s)
Hidrolisados de Proteína , Subtilisinas , Hidrolisados de Proteína/química , Subtilisinas/metabolismo , Suero Lácteo/metabolismo , Proteína de Suero de Leche , Péptidos/química , Proteínas Sanguíneas
12.
Int J Food Microbiol ; 419: 110738, 2024 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-38772219

RESUMEN

This study investigates the possibility of utilizing drip as a non-destructive method for assessing the freshness and spoilage of chicken meat. The quality parameters [pH, volatile base nitrogen (VBN), and total aerobic bacterial counts (TAB)] of chicken meat were evaluated over a 13-day storage period in vacuum packaging at 4 °C. Simultaneously, the metabolites in the chicken meat and its drip were measured by nuclear magnetic resonance. Correlation (Pearson's and Spearman's rank) and pathway analyses were conducted to select the metabolites for model training. Binary logistic regression (model 1 and model 2) and multiple linear regression models (model 3-1 and model 3-2) were trained using selected metabolites, and their performance was evaluated using receiver operating characteristic (ROC) curves. As a result, the chicken meat was spoiled after 7 days of storage, exceeding 20 mg/100 g VBN and 5.7 log CFU/g TAB. The correlation analysis identified one organic acid, eight free amino acids, and five nucleic acids as highly correlated with chicken meat and its drip during storage. Pathway analysis revealed tyrosine and purine metabolism as metabolic pathways highly correlated with spoilage. Based on these findings, specific metabolites were selected for model training: ATP, glutamine, hypoxanthine, IMP, tyrosine, and tyramine. To predict the freshness and spoilage of chicken meat, model 1, trained using tyramine, ATP, tyrosine, and IMP from chicken meat, achieved a 99.9 % accuracy and had an ROC value of 0.884 when validated using drip metabolites. This model 1 was improved by training with tyramine and IMP from both chicken meat and its drip (model 2), which increased the ROC value for drip metabolites from 0.884 to 0.997. Finally, selected two metabolites (tyramine and IMP) can predict TAB and VBN quantitatively through models 3-1 and 3-2, respectively. Therefore, the model developed using metabolic changes in drip demonstrated the capability to non-destructively predict the freshness and spoilage of chicken meat at 4 °C. To make generic predictions, it is necessary to expand the model's applicability to various conditions, such as different temperatures, and validate its performance across multiple chicken batches.


Asunto(s)
Pollos , Embalaje de Alimentos , Carne , Animales , Carne/microbiología , Carne/análisis , Embalaje de Alimentos/métodos , Microbiología de Alimentos , Almacenamiento de Alimentos , Recuento de Colonia Microbiana , Vacio , Contaminación de Alimentos/análisis
13.
West J Nurs Res ; 46(2): 104-113, 2024 02.
Artículo en Inglés | MEDLINE | ID: mdl-38112102

RESUMEN

BACKGROUND: Various factors drive a care setting shift from institutional to home settings for dementia care until the latest stage of the disease, suggesting the critical role of family caregivers living with persons with dementia. OBJECTIVES: This study explored the characteristics and correlates of self-reported overall physical and psychological (ie, depressive symptoms and stress) health among family caregivers living with persons with dementia in Sweden. METHODS: This cross-sectional, descriptive study used baseline data from an existing music-based intervention study of persons with dementia and their family caregivers (N = 76). Multivariable linear regression analyses were performed. RESULTS: On average, caregivers (n = 38; mean age: 74.8 years) were slightly younger than persons with dementia (n = 38; mean age: 78.6 years). Most caregivers were female (n = 24; 63.2%) and spouses or partners of persons with dementia (n = 37; 97.4%). Caregivers' perceived relationship with their family members with dementia was the only factor associated with caregivers' self-reported overall physical health (b = -0.655, p = .046). This suggests caregivers' more frequent feeling of a good relationship with the persons with dementia was linked to better self-rated physical health among family caregivers living with persons with dementia. CONCLUSIONS: This study highlights the importance of family caregivers' perceived relationship with persons with dementia in the context of caregivers' self-reported physical health. Future research is needed to explore the perceived relationship from the perspectives of persons with dementia and the determinants of caregiving dyads' (persons with dementia and family caregivers) perceived relationship with each other.


Asunto(s)
Cuidadores , Demencia , Humanos , Femenino , Anciano , Masculino , Cuidadores/psicología , Estudios Transversales , Familia/psicología , Esposos
14.
Food Funct ; 15(8): 4564-4574, 2024 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-38584588

RESUMEN

This study aimed to investigate the potential of beef peptides (BPs) in mitigating muscle atrophy induced by dexamethasone (DEX) with underlying three mechanisms in vitro (protein degradation, protein synthesis, and the oxidative stress pathway). Finally, the anti-atrophic effect of BPs was enhanced through purification and isolation. BPs were generated using beef loin hydrolyzed with alcalase/ProteAX/trypsin, each at a concentration of 0.67%, followed by ultrafiltration through a 3 kDa cut-off. BPs (10-100 µg mL-1) dose-dependently counteracted the DEX-induced reductions in myotube diameters, differentiation, fusion, and maturation indices (p < 0.05). Additionally, BPs significantly reduced FoxO1 protein dephosphorylation, thereby suppressing muscle-specific E3 ubiquitin ligases such as muscle RING-finger containing protein-1 and muscle atrophy F-box protein in C2C12 myotubes at concentrations exceeding 25 µg mL-1 (p < 0.05). BPs also enhanced the phosphorylation of protein synthesis markers, including mTOR, 4E-BP1, and p70S6K1, in a dose-dependent manner (p < 0.05) and increased the mRNA expression of antioxidant enzymes. Fractionated peptides derived from BPs, through size exclusion and polarity-based fractionation, also demonstrated enhanced anti-atrophic effects compared to BPs. These peptides downregulated the mRNA expression of primary muscle atrophy markers while upregulated that of antioxidant enzymes. Specifically, peptides GAGAAGAPAGGA (MW 924.5) and AFRSSTKK (MW 826.4) were identified from fractionated peptides of BPs. These findings suggest that BPs, specifically the peptide fractions GAGAAGAPAGGA and AFRSSTKK, could be a potential strategy to mitigate glucocorticoid-induced skeletal muscle atrophy by reducing the E3 ubiquitin ligase activity.


Asunto(s)
Fibras Musculares Esqueléticas , Atrofia Muscular , Estrés Oxidativo , Péptidos , Animales , Atrofia Muscular/tratamiento farmacológico , Atrofia Muscular/metabolismo , Fibras Musculares Esqueléticas/efectos de los fármacos , Fibras Musculares Esqueléticas/metabolismo , Ratones , Estrés Oxidativo/efectos de los fármacos , Péptidos/farmacología , Bovinos , Proteolisis/efectos de los fármacos , Línea Celular , Biosíntesis de Proteínas/efectos de los fármacos , Carne Roja , Proteínas Musculares/metabolismo , Dexametasona/farmacología , Músculo Esquelético/efectos de los fármacos , Músculo Esquelético/metabolismo , Fosforilación , Serina-Treonina Quinasas TOR/metabolismo
15.
J Colloid Interface Sci ; 675: 104-116, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38968631

RESUMEN

Exploring precious metal-free bifunctional electrocatalysts for both the oxygen reduction reaction (ORR) and the oxygen evolution reaction (OER) is essential for the practical application of rechargeable Zn-air battery (ZAB). Herein, Ni-doped Co9S8 nanoparticles embedded in a defect-rich N, S co-doped carbon matrix (d-NixCo9-xS8@NSC) are synthesized via a facile pyrolysis and acid treatment process. The introduction of abundant defects in both the carbon matrix and metal sulfide provides numerous active sites and significantly enhances the electrocatalytic performances for both the ORR and OER. d-NixCo9-xS8@NSC exhibits a superior half-wave potential of 0.841 V vs. RHE for the ORR and delivers a low overpotential of 0.329 V at 10 mA cm-2 for the OER. Additionally, Zn-air secondary battery using d-NixCo9-xS8@NSC as the air cathode displays a higher specific capacity of 734 mAh gZn-1 and a peak power density of 148.03 mW cm-2 compared to those of state-of-the-art Pt/C-RuO2 (673 mAh gZn-1 and 136.9 mW cm-2, respectively). These findings underscore the potential of d-NixCo9-xS8@NSC as a high-performance electrocatalyst for secondary ZABs, offering new perspectives on the design of efficient noble metal-free electrocatalysts for future energy storage and conversion applications.

16.
Nanomaterials (Basel) ; 14(2)2024 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-38251164

RESUMEN

A synaptic device with a multilayer structure is proposed to reduce the operating power of neuromorphic computing systems while maintaining a high-density integration. A simple metal-insulator-metal (MIM)-structured multilayer synaptic device is developed using an 8-inch wafer-based and complementary metal-oxide-semiconductor (CMOS) fabrication process. The three types of MIM-structured synaptic devices are compared to assess their effects on reducing the operating power. The obtained results exhibited low-power operation owing to the inserted layers acting as an internal resistor. The modulated operational conductance level and simple MIM structure demonstrate the feasibility of implementing both low-power operation and high-density integration in multilayer synaptic devices.

17.
Biomimetics (Basel) ; 9(6)2024 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-38921209

RESUMEN

We propose a genetic algorithm for optimizing oil skimmer assignments, introducing a tailored repair operation for constrained assignments. Methods essentially involve simulation-based evaluation to ensure adherence to South Korea's regulations. Results show that the optimized assignments, compared to current ones, reduced work time on average and led to a significant reduction in total skimmer capacity. Additionally, we present a deep neural network-based surrogate model, greatly enhancing efficiency compared to simulation-based optimization. Addressing inefficiencies in mobilizing locations that store oil skimmers, further optimization aimed to minimize mobilized locations and was validated through scenario-based simulations resembling actual situations. Based on major oil spills in South Korea, this strategy significantly reduced work time and required locations. These findings demonstrate the effectiveness of the proposed genetic algorithm and mobilized location minimization strategy in enhancing oil spill response operations.

18.
Meat Sci ; 216: 109577, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-38964227

RESUMEN

This study aimed to evaluate the sous-vide cooking and ficin treatment effects on the tenderness of beef steak and optimize it for the elderly using response surface methodology (RSM). The M. semitendinosus (ST) from Chikso cattle was shaped into 5 × 5 × 2.54 cm pieces. Ficin solution was injected into the ST steak at 10% of the meat weight, and sous-vide cooked in a water bath at 65 °C for 6 or 12 h. As ficin concentration increased, L*- and a*-value, shear force, and hardness decreased, while soluble peptides increased (P < 0.05). As cooking time increased, cooking loss and collagen solubility of the steak increased (P < 0.05). An interaction effect between ficin and sous-vide cooking was found in L*- and a*-value, shear force, hardness, and soluble peptides (P < 0.05). A model to optimize the hardness for elderly people was established (R2 = 0.7991). Optimization conditions by RSM were 0.86 U/L with 8.87 h (23 N/cm3) for tooth intake (grade 1), 16.31 U/L with 13.24 h (3 N/cm3) for gums intake (grade 2), according to KS H 4897 and Universal Design Foods concept for the elderly. These optimized conditions enable the production of customized products tailored to the oral conditions of elderly people.


Asunto(s)
Culinaria , Músculo Esquelético , Carne Roja , Animales , Bovinos , Humanos , Carne Roja/análisis , Músculo Esquelético/química , Dureza , Color , Colágeno/análisis , Anciano
19.
Eur J Med Chem ; 268: 116253, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38401188

RESUMEN

This study explores the potential of CSF-1R inhibitors as therapeutic agents for neurodegenerative diseases. CSF-1R, a receptor tyrosine kinase primarily expressed in macrophage lineages, plays a pivotal role in regulating various cellular processes. Recent research highlights the significance of CSF-1R inhibition in mitigating neuroinflammation, particularly in Alzheimer's disease, where microglial overactivation contributes to neurodegeneration. The research reveals a series of N-(5-amido-2-methylphenyl)-5-methylisoxazole-3-carboxamide CSF-1R inhibitors, where compounds 7d, 7e, and 9a exhibit outstanding inhibitory activities and selectivity, with IC50 values of 33, 31, and 64 nM, respectively. These most promising compounds in this series were profiled for cellular potency and subjected to in vitro pharmacokinetic profiling. These inhibitors exhibit minimal cytotoxicity, even at higher concentrations, and possess promising blood-brain barrier permeability, making them potential candidates for central nervous system diseases. The investigation into the in vitro ADME properties, including plasma and microsomal stability, reveals that these CSF-1R inhibitors maintain their structural integrity and plasma concentration. This resilience positions them for further development as therapeutic agents for neurodegenerative diseases.


Asunto(s)
Isoxazoles , Enfermedades Neurodegenerativas , Receptor de Factor Estimulante de Colonias de Macrófagos , Humanos , Receptor de Factor Estimulante de Colonias de Macrófagos/química , Receptor de Factor Estimulante de Colonias de Macrófagos/metabolismo , Barrera Hematoencefálica/metabolismo , Proteínas Tirosina Quinasas Receptoras , Inhibidores Enzimáticos
20.
Gland Surg ; 13(3): 340-350, 2024 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-38601290

RESUMEN

Background: The changing medical education environment emphasizes the need for time efficiency, increasing the demand for competency-based medical education to improve trainees' learning strategies. This study was performed to determine the competencies required for successful performance of robotic thyroidectomy (RT) and to determine the consensus of experts for performance of RT. Methods: Data were collected through 12 semi-structured interviews with RT experts and 11 field observations. Cognitive task analysis was performed to determine the competencies required for experts to perform RT. A modified Delphi methodology was used to determine how 20 experts rated the importance of each item of RT performance on a Likert 7-point scale. The criteria for the Delphi consensus were set at a Cronbach's α≥0.80 with two survey rounds. Results: After 11 field observations and 12 semi-structured interviews, 89 items were identified within six modules. These items were grouped into sub-modules according to their theme. The modified Delphi survey, involving 21 experts, reached the consensus standard during the second round (Cronbach's α=0.954), enabling the identification of the 64 most important items within six modules related to RT performance: midline incision to isthmectomy (MID module; n=8), lateral dissection (LAT module; n=7), preservation of inferior parathyroid glands (INF module; n=16), preservation of recurrent laryngeal nerve and dissection of the ligament of Berry (BER module; n=21), dissection of the thyroid upper pole (SUP module; n=10), and specimen removal and closure (END module; n=2). Conclusions: This mixed-method study combining qualitative and quantitative methodology identified modules of core competencies required to perform RT. These modules can be used as a standard and objective guide to train surgeons to perform RT and evaluate outcomes.

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