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1.
Bioact Mater ; 43: 67-81, 2025 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-39328776

RESUMEN

Current cancer immunotherapies exhibit low response rates attributed to suppressive tumor immune microenvironments (TIMEs). To address these unfavorable TIMEs, supplementation with tumor-associated antigens and stimulation of immune cells at target sites are indispensable for eliciting anti-tumoral immune responses. Previous research has explored the induction of immunotherapy through multiple injections and implants; however, these approaches lack consideration for patient convenience and the implementation of finely tunable immune response control systems to mitigate the side effects of over-inflammatory responses, such as cytokine storms. In this context, we describe a patient-centric nano-gel-nano system capable of sustained generation of tumor-associated antigens and release of adjuvants. This is achieved through the specific delivery of drugs to cancer cells and antigens/adjuvants to immune cells over the long term, maintaining proper concentrations within the tumor site with a single injection. This system demonstrates local immunity against tumors with a single injection, enhances the therapeutic efficacy of immune checkpoint blockades, and induces systemic and memory T cell responses, thus minimizing systemic side effects.

2.
Int J Epidemiol ; 53(5)2024 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-39373550

RESUMEN

BACKGROUND: The healthy worker effect may distort the association between exposure and health effects in workers. However, few studies have investigated both the healthy worker hire and survival effects simultaneously, and they are limited to mortality studies in male workers. METHODS: We utilized a data set comprising South Korean diagnostic medical radiation workers registered in the National Dose Registry between 1996 and 2011, and merged it with mortality and cancer incidence data. Standardized mortality ratios (SMRs) and standardized incidence ratios (SIRs) were computed for comparison with the general population. To account for time-varying confounders influenced by prior occupational radiation exposure, we applied g-estimation using structural nested accelerated failure time models and compared the outcomes with those from Weibull regression. RESULTS: A total of 1831 deaths and 3759 first primary cancer cases were identified among 93 918 workers. Both male (SMR = 0.44; 95% CI: 0.42, 0.46) and female workers (SMR = 0.53; 95% CI: 0.46, 0.60) showed lower mortality rates compared with national rates. In the SIR analysis, male workers exhibited reduced risks of solid cancer whereas female workers had increased risks. The g-estimation-derived hazard ratios (HRs) from radiation exposure exceeded those from Weibull regression estimates for all-cause death (HR = 2.55; 95% CI: 1.97, 3.23) and all-cancer incidence (HR = 1.96; 95% CI: 1.52, 2.55) in male workers whereas female workers showed the opposite results. CONCLUSIONS: Comprehensive consideration of the healthy worker effect by sex is essential for estimating the unbiased impact of occupational exposure on health outcomes, notably in studies focusing on male mortality.


Asunto(s)
Neoplasias Inducidas por Radiación , Exposición Profesional , Humanos , Masculino , Femenino , Exposición Profesional/efectos adversos , Exposición Profesional/estadística & datos numéricos , República de Corea/epidemiología , Persona de Mediana Edad , Adulto , Efecto del Trabajador Sano , Neoplasias Inducidas por Radiación/epidemiología , Neoplasias Inducidas por Radiación/mortalidad , Incidencia , Sistema de Registros , Modelos de Riesgos Proporcionales , Estudios de Cohortes , Exposición a la Radiación/efectos adversos , Sobrevivientes/estadística & datos numéricos , Anciano , Enfermedades Profesionales/epidemiología , Enfermedades Profesionales/mortalidad
3.
J Food Sci ; 2024 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-39366779

RESUMEN

The objective of this study was to optimize the microbial and ingredient composition of kombucha for enhanced production of gluconic acid (GA). Fourteen strains of Komagataeibacter spp. and one yeast strain of Dekkera sp. were isolated from kombucha. Among them, Komagataeibacter swingsii SS1 (SS1) and Komagataeibacter saccharivorans SS11 (SS11) were selected for their high GA production. A rapid reduction of pH, high GA content relative to acetic acid, and high cellulose production were observed in the tea infusion fermented by the microbial consortium (SS1 + SS11 + Dekkera bruxellensis Y24). From the correlation between the materials composition and quality indicators of kombucha, the decrease in pH was the most critical quality indicator of kombucha and the most closely related to GA content. Maximal GA production (11.7 mg/mL) was obtained under the conditions of 1% (w/v) tea extract, 8.5% (w/v) glucose, and 1.5% (v/v) ethanol through the optimization of materials composition by response surface methodology. The GA content of kombucha was enhanced threefold in comparison to general kombucha by fermentation with Komagataeibacter spp. and optimization of the composition of the ingredients. Overall, this study showed that a specific microbial consortium and materials composition could be established by correlation analysis among the ingredients, which results in increased GA levels in kombucha. These findings offer valuable foundational data for both commercial production and quality control of kombucha.

4.
JMIR Form Res ; 8: e47814, 2024 Oct 18.
Artículo en Inglés | MEDLINE | ID: mdl-39423004

RESUMEN

BACKGROUND: Patients often struggle with determining which outpatient specialist to consult based on their symptoms. Natural language processing models in health care offer the potential to assist patients in making these decisions before visiting a hospital. OBJECTIVE: This study aimed to evaluate the performance of ChatGPT in recommending medical specialties for medical questions. METHODS: We used a dataset of 31,482 medical questions, each answered by doctors and labeled with the appropriate medical specialty from the health consultation board of NAVER (NAVER Corp), a major Korean portal. This dataset includes 27 distinct medical specialty labels. We compared the performance of the fine-tuned Korean Medical bidirectional encoder representations from transformers (KM-BERT) and ChatGPT models by analyzing their ability to accurately recommend medical specialties. We categorized responses from ChatGPT into those matching the 27 predefined specialties and those that did not. Both models were evaluated using performance metrics of accuracy, precision, recall, and F1-score. RESULTS: ChatGPT demonstrated an answer avoidance rate of 6.2% but provided accurate medical specialty recommendations with explanations that elucidated the underlying pathophysiology of the patient's symptoms. It achieved an accuracy of 0.939, precision of 0.219, recall of 0.168, and an F1-score of 0.134. In contrast, the KM-BERT model, fine-tuned for the same task, outperformed ChatGPT with an accuracy of 0.977, precision of 0.570, recall of 0.652, and an F1-score of 0.587. CONCLUSIONS: Although ChatGPT did not surpass the fine-tuned KM-BERT model in recommending the correct medical specialties, it showcased notable advantages as a conversational artificial intelligence model. By providing detailed, contextually appropriate explanations, ChatGPT has the potential to significantly enhance patient comprehension of medical information, thereby improving the medical referral process.


Asunto(s)
Procesamiento de Lenguaje Natural , Humanos , República de Corea , Derivación y Consulta , Pacientes Ambulatorios
5.
Biomater Res ; 28: 0087, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39319107

RESUMEN

Although curcumin has been well known as a phytochemical drug that inhibits tumor promotion by modulating multiple molecular targets, its potential was not reported as a targeting ligand in the field of drug delivery system. Here, we aimed to assess the tumor-targeting efficiency of curcumin and its derivatives such as phenylalanine, cinnamic acid, coumaric acid, and ferulic acid. Curcumin exhibited a high affinity for estrogen receptors through a pull-down assay using the membrane proteins of MCF-7, a breast cancer cell line, followed by designation of a polymer-based gene therapy system. As a basic backbone for gene binding, dextran grafted with branched polyethylenimine was synthesized, and curcumin and its derivatives were linked to lysine dendrimers. In vitro and in vivo antitumor effects were evaluated using plasmid DNA expressing anti-bcl-2 short hairpin RNA. All synthesized gene carriers showed excellent DNA binding, protective effects against nuclease, and gene transfection efficiency in MCF-7 and SKBr3 breast cancer cells. Preincubation with curcumin or 17α-estradiol resulted in a marked dose-dependent decrease in gene transfer efficiency and suggested targeting specificity of curcumin. Our study indicates the potential of curcumin and its derivatives as novel targeting ligands for tumor cells and tissues.

6.
Int J Biol Macromol ; 279(Pt 3): 135402, 2024 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-39245114

RESUMEN

Amphotericin B (AmB) is an antifungal agent administered for the management of serious systemic fungal infections. However, its clinical application is limited because of its water insolubility and side effects. Herein, to apply the minimum dose of AmB that can be used to manage fungal infections, a targeted drug delivery system was designed using lipopeptides and poly(lactide-co-glycolide) (PLGA). Lipopeptides conjugated with PEGylated distearoyl phosphoethanolamine (DSPE) and short peptides via a maleimide-thiol reaction formed nanosized micelles with PLGA and AmB. The antifungal effects of AmB-loaded micelles containing lipopeptides were remarkably enhanced both in vitro and in vivo. Moreover, the intravenous injection of these micelles demonstrated their in vivo targeting capacity of short peptides in a mouse model infected with drug-resistant Candida albicans. Our findings suggest that short antifungal peptides displayed on the surfaces of micelles represent a promising therapeutic candidate for targeting drug-resistant fungal infections.


Asunto(s)
Anfotericina B , Antifúngicos , Candida albicans , Candidiasis , Farmacorresistencia Fúngica , Lipopéptidos , Micelas , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Anfotericina B/química , Anfotericina B/farmacología , Anfotericina B/administración & dosificación , Animales , Copolímero de Ácido Poliláctico-Ácido Poliglicólico/química , Ratones , Candida albicans/efectos de los fármacos , Candidiasis/tratamiento farmacológico , Farmacorresistencia Fúngica/efectos de los fármacos , Antifúngicos/farmacología , Antifúngicos/química , Antifúngicos/administración & dosificación , Lipopéptidos/química , Lipopéptidos/farmacología , Portadores de Fármacos/química , Sistemas de Liberación de Medicamentos , Piel/efectos de los fármacos , Piel/microbiología , Polietilenglicoles/química , Fosfatidiletanolaminas/química , Pruebas de Sensibilidad Microbiana
7.
Anal Methods ; 16(39): 6751-6758, 2024 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-39344606

RESUMEN

The analysis of microplastics is crucial due to their widespread occurrence and significant impact as environmental pollutants. Appropriate extraction and analytical techniques are necessary to evaluate the abundance, dispersal, and effects of microplastics. In this context, the filtration step to extract microplastics from solution media is indispensable for quantifying microplastics accurately. Usually, a pretreatment procedure such as density separation or solvent extraction is employed before filtration. Nevertheless, the adsorption of microplastic particles onto the glassware surface is known to occur and careful rinsing is inevitable for a suitable recovery rate. The study presents a novel filtration device developed for easy use to increase microplastic recovery from liquid samples. Fluorescent polyethylene (PE) particles were used to examine recovery by optical microscopy and pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS). The conventional filtration system (CFS) exhibited lower microplastic recovery (45.1 ± 7.9%, n = 10) due to the adsorption of microplastics onto the inner surface and the bottom edge of the upper glass funnel. In contrast, the newly developed modified filtration system (MFS) enables fast suction of liquid samples by removing the glass frit with the upper glass funnel and filter being spatially separated. The significantly improved recovery rates using MFS for PE particles were 100% (n = 5) and 93.4 ± 3.4% (n = 10), respectively, confirming the feasibility of the newly developed filtration system to analyze microplastics using Py-GC/MS. The study highlights the importance of filtration processing in establishing analytical standards for assessing and managing microplastics by suggesting MFS as an advanced filtration system.

8.
Biomol Ther (Seoul) ; 32(5): 556-567, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-39091181

RESUMEN

ß-glucan, a polysaccharide found in various sources, exhibits unique physicochemical properties, yet its high polymerization limits clinical applications because of its solubility. Addressing this limitation, we introduce PPTEE-glycan, a highly purified soluble ß-1,3/1,6-glucan derived from Aureobasidium pullulans. The refined PPTEE-glycan demonstrated robust immune stimulation in vitro, activated dendritic cells, and enhanced co-stimulatory markers, cytokines, and cross-presentation. Formulated as a PPTEE + microemulsion (ME), it elevated immune responses in vivo, promoting antigen-specific antibodies and CD8+ T cell proliferation. Intratumoral administration of PPTEE + ME in tumor-bearing mice induced notable tumor regression, which was linked to the activation of immunosuppressive cells. This study highlights the potential of high-purity Aureobasidium pullulans-derived ß-glucan, particularly PPTEE, as promising immune adjuvants, offering novel avenues for advancing cancer immunotherapy.

9.
Nat Immunol ; 25(10): 1943-1958, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39179931

RESUMEN

The drivers of immune evasion are not entirely clear, limiting the success of cancer immunotherapies. Here we applied single-cell spatial and perturbational transcriptomics to delineate immune evasion in high-grade serous tubo-ovarian cancer. To this end, we first mapped the spatial organization of high-grade serous tubo-ovarian cancer by profiling more than 2.5 million cells in situ in 130 tumors from 94 patients. This revealed a malignant cell state that reflects tumor genetics and is predictive of T cell and natural killer cell infiltration levels and response to immune checkpoint blockade. We then performed Perturb-seq screens and identified genetic perturbations-including knockout of PTPN1 and ACTR8-that trigger this malignant cell state. Finally, we show that these perturbations, as well as a PTPN1/PTPN2 inhibitor, sensitize ovarian cancer cells to T cell and natural killer cell cytotoxicity, as predicted. This study thus identifies ways to study and target immune evasion by linking genetic variation, cell-state regulators and spatial biology.


Asunto(s)
Neoplasias Ováricas , Escape del Tumor , Femenino , Humanos , Neoplasias Ováricas/inmunología , Neoplasias Ováricas/genética , Células Asesinas Naturales/inmunología , Análisis de la Célula Individual , Línea Celular Tumoral , Linfocitos T/inmunología , Regulación Neoplásica de la Expresión Génica , Microambiente Tumoral/inmunología , Evasión Inmune , Linfocitos Infiltrantes de Tumor/inmunología , Linfocitos Infiltrantes de Tumor/metabolismo
10.
Resusc Plus ; 19: 100725, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39091585

RESUMEN

Introduction: Dispatcher-assisted cardiopulmonary resuscitation (DA-CPR) improves bystander CPR rates and survival outcomes. This study aimed to identify barriers to successful DA-CPR in patients with out-of-hospital cardiac arrest (OHCA). Methods: This retrospective observational study used data from a nationwide OHCA database from 2017 to 2021. Adult emergency medical services (EMS)-treated patients with OHCA with a presumed cardiac etiology were enrolled. The main exposure variable was compliance with DA-CPR. The primary outcome was good neurological recovery at hospital discharge. Multivariable logistic regression analysis was conducted to identify the major factors associated with unsuccessful DA-CPR with and without multiple imputations. Causal mediation analysis was conducted using witnessed status as a mediator. Results: In the final analysis, 49,165 patients with OHCA were included. A total of 36,865 (75.0%) patients successfully underwent DA-CPR. A higher proportion of good neurological recovery was observed in the successful DA-CPR group than in the non-successful DA-CPR group (P < 0.001). The following factors were identified as risk factors for unsuccessful DA-CPR: age > 65 years, male sex, OHCA occurring in a non-metropolitan area or private place, unwitnessed status, whether the bystander was a non-family member or non-cohabitant, female sex or had not received CPR training, and primary call dispatchers not receiving any first-aid training. Additional analyses after multiple imputations showed similar results. Mediation effect was significant for most risk factors for unsuccessful DA-CPR. Conclusions: Bystander characteristics (non-family member or non-cohabitant, female, and uneducated status for CPR) and primary call dispatchers not receiving first-aid training were identified as risk factors for unsuccessful DA-CPR.

11.
Micromachines (Basel) ; 15(8)2024 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-39203661

RESUMEN

The radial pulse is a critical health marker with expanding applications in wearable technology. To improve these applications, developing a pulse generator that consistently produces realistic pulses is crucial for validation and training. The goal of this study was to design and test a cost-effective pulse simulator that can accurately replicate a wide range of age-dependent radial pulses with simplicity and precision. To this end, this study incorporated a magneto-rheological (MR) fluid device into a cam-based pulse simulator. The MR device, as a key component, enables pulse shaping without the need for additional cams, substantially reducing the cost and complexity of control compared with existing pulse simulators. To evaluate the performance of the MR pulse simulator, the root-mean-square (RMS) error criterion (less than 5%) was used to compare the experimentally obtained pulse waveform with the in vivo pulse waveform for specific age groups. After demonstrating that the MR simulator could produce three representative in vivo pulses, a parametric study was conducted to show the feasibility of the slope-based pulse-shaping method for the MR pulse simulator to continuously generate a range of age-related pulses.

12.
Adv Mater ; 36(36): e2403783, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39023001

RESUMEN

In 2D noble metals like copper, the carrier scattering at grain boundaries has obscured the intrinsic nature of electronic transport. However, it is demonstrated that the intrinsic nature of transport by hole carriers in 2D copper can be revealed by growing thin films without grain boundaries. As even a slight deviation from the twin boundary is perceived as grain boundaries by electrons, it is only through the thorough elimination of grain boundaries that the hidden hole-like attribute of 2D single-crystal copper can be unmasked. Two types of Fermi surfaces, a large hexagonal Fermi surface centered at the zone center and the triangular Fermi surface around the zone corner, tightly matching to the calculated Fermi surface topology, confirmed by angle-resolved photoemission spectroscopy (ARPES) measurements and vivid nonlinear Hall effects of the 2D single-crystal copper account for the presence of hole carriers experimentally. This breakthrough suggests the potential to manipulate the majority carrier polarity in metals by means of grain boundary engineering in a 2D geometry.

13.
Inj Prev ; 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-39009433

RESUMEN

OBJECTIVE: This study investigated the differences in injury profiles and safety device effectiveness among children with road traffic injuries (RTIs) involving passenger vehicles and school buses. METHODS: Using data from the Emergency Department-based Injury In-depth Surveillance database, this multicentre cross-sectional study investigated the injury profiles of 14 669 children aged 12 years old and younger who experienced RTIs from 2011-2021. Demographic factors, injury distribution, severity and effect of safety device use between RITs involving passenger vehicles and school buses were compared. RESULTS: RTIs in children most frequently occurred between 12:00 and 18:00 hours (46.9%). School bus-related RTIs peaked during school commute hours, that is, from 06:00 to 12:00 hours, and were associated with a higher prevalence of head (63.1% vs 58.9%, p<0.05) and extremity injuries (upper extremity: 8.0% vs 6.4% and lower extremity: 11.1% vs 7.6 %, p<0.05) compared with those involving passenger vehicles. However, passenger vehicle crashes showed higher proportions of neck and chest injuries, along with injuries requiring hospitalisation and intensive care. Safety devices exhibited preventive effects against head and lower extremity injuries in both vehicle types. While safety devices showed effective in reducing hospital admissions and severe injuries in passenger vehicles, their effectiveness in school buses was not observed. CONCLUSION: This study highlights the different epidemiology and injury profiles of RTIs among children involving passenger vehicles and school buses. Improved safety devices, particularly in school buses, are necessary to ensure the comprehensive protection of child passengers and reduce the risk of severe injuries during road traffic incidents.

14.
JMIR Med Educ ; 10: e51282, 2024 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-38989848

RESUMEN

Background: Accurate medical advice is paramount in ensuring optimal patient care, and misinformation can lead to misguided decisions with potentially detrimental health outcomes. The emergence of large language models (LLMs) such as OpenAI's GPT-4 has spurred interest in their potential health care applications, particularly in automated medical consultation. Yet, rigorous investigations comparing their performance to human experts remain sparse. Objective: This study aims to compare the medical accuracy of GPT-4 with human experts in providing medical advice using real-world user-generated queries, with a specific focus on cardiology. It also sought to analyze the performance of GPT-4 and human experts in specific question categories, including drug or medication information and preliminary diagnoses. Methods: We collected 251 pairs of cardiology-specific questions from general users and answers from human experts via an internet portal. GPT-4 was tasked with generating responses to the same questions. Three independent cardiologists (SL, JHK, and JJC) evaluated the answers provided by both human experts and GPT-4. Using a computer interface, each evaluator compared the pairs and determined which answer was superior, and they quantitatively measured the clarity and complexity of the questions as well as the accuracy and appropriateness of the responses, applying a 3-tiered grading scale (low, medium, and high). Furthermore, a linguistic analysis was conducted to compare the length and vocabulary diversity of the responses using word count and type-token ratio. Results: GPT-4 and human experts displayed comparable efficacy in medical accuracy ("GPT-4 is better" at 132/251, 52.6% vs "Human expert is better" at 119/251, 47.4%). In accuracy level categorization, humans had more high-accuracy responses than GPT-4 (50/237, 21.1% vs 30/238, 12.6%) but also a greater proportion of low-accuracy responses (11/237, 4.6% vs 1/238, 0.4%; P=.001). GPT-4 responses were generally longer and used a less diverse vocabulary than those of human experts, potentially enhancing their comprehensibility for general users (sentence count: mean 10.9, SD 4.2 vs mean 5.9, SD 3.7; P<.001; type-token ratio: mean 0.69, SD 0.07 vs mean 0.79, SD 0.09; P<.001). Nevertheless, human experts outperformed GPT-4 in specific question categories, notably those related to drug or medication information and preliminary diagnoses. These findings highlight the limitations of GPT-4 in providing advice based on clinical experience. Conclusions: GPT-4 has shown promising potential in automated medical consultation, with comparable medical accuracy to human experts. However, challenges remain particularly in the realm of nuanced clinical judgment. Future improvements in LLMs may require the integration of specific clinical reasoning pathways and regulatory oversight for safe use. Further research is needed to understand the full potential of LLMs across various medical specialties and conditions.


Asunto(s)
Inteligencia Artificial , Cardiología , Humanos , Cardiología/normas
15.
Carbohydr Polym ; 340: 122270, 2024 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-38858000

RESUMEN

Targeted and stimuli-responsive drug delivery enhances therapeutic efficacy and minimizes undesirable side effects of cancer treatment. Although cellulose nanocrystals (CNCs) are used as drug carriers because of their robustness, spindle shape, biocompatibility, renewability, and nontoxicity, the lack of programmability and functionality of CNCs-based platforms hampers their application. Thus, high adaptability and the capacity to form dynamic 3D nanostructures of DNA may be advantageous, as they can provide functionalities such as target-specific and stimuli-responsive drug release. Using DNA nanotechnology, the functional polymeric form of DNA nanostructures can be replicated using rolling circle amplification (RCA), and the biologically and physiologically stable DNA nanostructures may overcome the challenges of CNCs. In this study, multifunctional polymeric DNAs produced with RCA were strongly complexed with surface-modified CNCs via electrostatic interactions to form polymeric DNA-decorated CNCs (pDCs). Particle size, polydispersity, zeta potential, and biostability of the nanocomplexes were analyzed. As a proof of concept, the dynamic structural functionalities of DNA nanostructures were verified by observing cancer-targeted intracellular delivery and pH-responsive drug release. pDCs showed anticancer properties without side effects in vitro, owing to their aptamer and i-motif functionalities. In conclusion, pDCs exhibited multifunctional anticancer activities, demonstrating their potential as a promising hybrid nanocomplex platform for targeted cancer therapy.


Asunto(s)
Celulosa , ADN , Portadores de Fármacos , Liberación de Fármacos , Nanopartículas , Nanoestructuras , Celulosa/química , Humanos , Nanopartículas/química , ADN/química , Nanoestructuras/química , Portadores de Fármacos/química , Sistemas de Liberación de Medicamentos , Antineoplásicos/química , Antineoplásicos/farmacología , Antineoplásicos/administración & dosificación , Polímeros/química , Concentración de Iones de Hidrógeno , Doxorrubicina/química , Doxorrubicina/farmacología , Doxorrubicina/administración & dosificación , Supervivencia Celular/efectos de los fármacos
16.
Nano Lett ; 24(26): 7979-7986, 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38829309

RESUMEN

Magnetic anisotropy in atomically thin correlated heterostructures is essential for exploring quantum magnetic phases for next-generation spintronics. Whereas previous studies have mostly focused on van der Waals systems, here we investigate the impact of dimensionality of epitaxially grown correlated oxides down to the monolayer limit on structural, magnetic, and orbital anisotropies. By designing oxide superlattices with a correlated ferromagnetic SrRuO3 and nonmagnetic SrTiO3 layers, we observed modulated ferromagnetic behavior with the change of the SrRuO3 thickness. Especially, for three-unit-cell-thick layers, we observe a significant 1500% improvement of the coercive field in the anomalous Hall effect, which cannot be solely attributed to the dimensional crossover in ferromagnetism. The atomic-scale heterostructures further reveal the systematic modulation of anisotropy for the lattice structure and orbital hybridization, explaining the enhanced magnetic anisotropy. Our findings provide valuable insights into engineering the anisotropic hybridization of synthetic magnetic crystals, offering a tunable spin order for various applications.

17.
Int J Toxicol ; 43(5): 472-490, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38897632

RESUMEN

The subchronic toxicity and toxicokinetics of a combination of rabeprazole sodium and sodium bicarbonate were investigated in dogs by daily oral administration for 13 consecutive weeks with a 4-week recovery period. The dose groups consisted of control (vehicles), (5 + 200), (10 + 400), and (20 + 800) mg/kg of rabeprazole sodium + sodium bicarbonate, 20 mg/kg of rabeprazole sodium only, and 800 mg/kg of sodium bicarbonate only. Esophageal ulceration accompanied by inflammation was observed in only one animal in the male (20 + 800) mg/kg rabeprazole sodium + sodium bicarbonate group. However, the severity of the ulceration was moderate, and the site of occurrence was focally extensive; thus, it was assumed to be a treatment-related effect of rabeprazole sodium + sodium bicarbonate. In the toxicokinetics component of this study, systemic exposure to rabeprazole sodium (AUClast and Cmax at Day 91) was greater in males than females, suggesting sex differences. AUClast and Cmax at Day 91 were increased compared to those on Day 1 in a dose-dependent manner. A delayed Tmax and no drug accumulation were observed after repeated dosage. In conclusion, we suggest under the conditions of this study that the no-observed-adverse-effect level (NOAEL) of the combination of rabeprazole sodium + sodium bicarbonate in male and female dogs is (10 + 400) and (20 + 800) mg/kg, respectively.


Asunto(s)
Rabeprazol , Bicarbonato de Sodio , Animales , Perros , Rabeprazol/farmacocinética , Rabeprazol/toxicidad , Rabeprazol/administración & dosificación , Masculino , Femenino , Administración Oral , Bicarbonato de Sodio/farmacocinética , Bicarbonato de Sodio/toxicidad , Bicarbonato de Sodio/administración & dosificación , Toxicocinética , Nivel sin Efectos Adversos Observados , Área Bajo la Curva , Relación Dosis-Respuesta a Droga , Combinación de Medicamentos , Pruebas de Toxicidad Subcrónica
18.
Nat Mater ; 23(7): 977-983, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38693448

RESUMEN

Homochirality is an important feature in biological systems and occurs even in inorganic nanoparticles. However, the mechanism of chirality formation and the key steps during growth are not fully understood. Here we identify two distinguishable pathways from achiral to chiral morphologies in gold nanoparticles by training an artificial neural network of cellular automata according to experimental results. We find that the chirality is initially determined by the nature of the asymmetric growth along the boundaries of enantiomeric high-index planes. The deep learning-based interpretation of chiral morphogenesis provides a theoretical understanding but also allows us to predict an unprecedented crossover pathway and the resulting morphology.

19.
ACS Appl Mater Interfaces ; 16(21): 27532-27540, 2024 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-38743018

RESUMEN

Robust ferroelectricity in HfO2-based ultrathin films has the potential to revolutionize nonvolatile memory applications in nanoscale electronic devices because of their compatibility with the existing Si technology. However, to fully exploit the potential of ferroelectric HfO2-based thin films, it is crucial to develop strategies for the controlled stabilization of various HfO2-based polymorphs in nanoscale heterostructures. This study demonstrates how substrate-orientation-induced anisotropic strain can engineer the crystal symmetry, structural domain morphology, and growth orientation of ultrathin Hf0.5Zr0.5O2 (HZO) films. Epitaxial ultrathin HZO films were grown on the heterostructures of (001)- and (110)-oriented La2/3Sr1/3MnO3/SrTiO3 (LSMO/STO) substrate. Various structural analyses revealed that the (110)-oriented substrate promotes a higher degree of structural order (crystallinity) with improved stability of the (111)-oriented orthorhombic phase (Pca21) of HZO. Conversely, the (001)-oriented substrate not only induces a distorted orthorhombic structure but also facilitates the partial stabilization of nonpolar phases. Electrical measurements revealed robust ferroelectric properties in epitaxial thin films without any wake-up effect, where the well-ordered crystal symmetry stabilized by STO(110) facilitated better ferroelectric characteristics. This study suggests that tuning the epitaxial growth of ferroelectric HZO through substrate orientation can improve the stability of the metastable ferroelectric orthorhombic phase and thereby offer a better understanding of device applications.

20.
J Biol Eng ; 18(1): 32, 2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38715027

RESUMEN

BACKGROUND: Adiponectin (ADPN) plays a critical role in endocrine and cardiovascular functions, but traditional production methods, such as Escherichia coli and mammalian systems, have faced challenges in generating sufficiently active middle molecular weight (MMW) and high molecular weight (HMW) forms of recombinant human ADPN (hADPN). In our previous study, we proposed genome-edited chickens as an efficient platform for producing multimeric hADPN. However, the consistency of multimeric hADPN expression in this system across generations had not been further investigated. RESULTS: In this study, subsequent generations of ovalbumin (OVA) ADPN knock-in chickens showed stable multimeric hADPN production, yielding ~ 26% HMW ADPN (0.59 mg/mL) per hen. Comparative analysis revealed that egg white (EW)-derived hADPN predominantly consisted of hexameric and HMW forms, similar to serum-derived hADPN. In contrast, hADPN obtained from human embryonic kidney (HEK) 293 and High-Five (Hi-5) cells also exhibited the presence of trimers, indicating variability across different production systems. Furthermore, transcriptional expression analysis of ADPN multimerization-associated endoplasmic reticulum chaperone genes (Ero1-Lα, DsbA-L, ERP44, and PDI) indicated upregulation in the oviduct magnum of ADPN KI hens, suggesting the chicken oviduct magnum as the optimal site for HMW ADPN production. Lastly, the functional analysis demonstrated that EW-derived hADPN significantly reduced lipid droplets and downregulated lipid accumulation-related genes (LOX-1, AT1R, FAS, and FABP4) in human umbilical vein endothelial cells (HUVECs). CONCLUSION: In summary, stable and functional multimeric hADPN can be produced in genome-edited chickens even after generations. This highlights the potential of using chicken bioreactor for producing various high-value proteins.

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