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1.
J Nutr ; 154(3): 896-907, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38301957

RESUMEN

BACKGROUND: Metallothioneins (MTs) have a strong affinity for zinc (Zn) and remain at a sufficiently high level in mitochondria. As the avian embryo is highly susceptible to oxidative damage and relatively easy to manipulate in a naturally closed chamber, it is an ideal model of the effects of oxidative stress on mitochondrial function. However, the protective roles and molecular mechanisms of Zn-inducible protein expression on mitochondrial function in response to various stressors are poorly understood. OBJECTIVES: The study aimed to investigate the mechanisms by which Zn-induced MT4 expression protects mitochondrial function and energy metabolism subjected to oxidative stress using the avian embryo and embryonic primary hepatocyte models. METHODS: First, we investigated whether MT4 expression alters mitochondrial function. Then, we examined the effects of Zn-induced MT4 overexpression and MT4 silencing on embryonic primary hepatocytes from breeder hens fed a normal Zn diet subjected to a tert-butyl hydroperoxide (BHP) oxidative stress challenge during incubation. In vivo, the avian embryos from hens fed the Zn-deficient and Zn-adequate diets were used to determine the protective roles of Zn-induced MT4 expression on the function of mitochondria exposed to oxidative stress induced by in ovo BHP injection. RESULTS: An in vitro study revealed that Zn-induced MT4 expression reduced reactive oxygen species accumulation in primary hepatocytes. MT4 silencing exacerbated BHP-mediated mitochondrial dysfunction whereas Zn-inducible MT4 overexpression mitigated it. Another in vivo study disclosed that maternal Zn-induced MT4 expression protected mitochondrial function in chick embryo hepatocytes against oxidative stress by inhibiting the peroxisome proliferator-activated receptor γ coactivator-1α (PGC-1α)/peroxisome proliferators-activated receptor-γ (PPAR-γ) pathway. CONCLUSION: This study underscores the potential protective roles of Zn-induced MT4 expression via the downregulation of the PGC-1α/PPAR-γ pathway on mitochondrial function stimulated by the stress challenge in the primary hepatocytes in an avian embryo model. Our findings suggested that Zn-induced MT4 expression could provide a new therapeutic target and preventive strategy for repairing mitochondrial dysfunction in disease.


Asunto(s)
Enfermedades Mitocondriales , Zinc , Embrión de Pollo , Animales , Femenino , Zinc/farmacología , Zinc/metabolismo , Pollos/metabolismo , Receptores Activados del Proliferador del Peroxisoma/metabolismo , Receptores Activados del Proliferador del Peroxisoma/farmacología , Mitocondrias/metabolismo , Estrés Oxidativo , Enfermedades Mitocondriales/metabolismo
2.
J Nat Prod ; 86(12): 2651-2660, 2023 12 22.
Artículo en Inglés | MEDLINE | ID: mdl-37967166

RESUMEN

Glioma is a clinically heterogeneous type of brain tumor with a poor prognosis. Current treatment approaches have limited effectiveness in treating glioma, highlighting the need for novel drugs. One approach is to explore marine natural products for their therapeutic potential. In this study, we isolated nine shikimate-derived diisoprenyl-cyclohexene/ane-type meroterpenoids (1-9), including four new ones, amphicordins A-D (1-4) from the ascidian-derived fungus Amphichorda felina SYSU-MS7908, and further semisynthesized four derivatives (10-13). Their structures were extensively characterized using 1D and 2D NMR, modified Mosher's method, HR-ESIMS, NMR and ECD calculations, and X-ray crystallography. Notably, amphicordin C (3) possesses a unique benzo[g]chromene (6/6/6) skeleton in this meroterpenoid family. In an anti-glioma assay, oxirapentyn A (7) effectively inhibited the proliferation, migration, and invasion of glioma cells and induced their apoptosis. Furthermore, an in silico analysis suggested that oxirapentyn A has the potential to penetrate the blood-brain barrier. These findings highlight the potential of oxirapentyn A as a candidate for the development of novel anti-glioma drugs.


Asunto(s)
Beauveria , Glioma , Urocordados , Animales , Humanos , Ácido Shikímico , Glioma/tratamiento farmacológico , Estructura Molecular
3.
Bioorg Chem ; 139: 106715, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37543015

RESUMEN

A combination strategy of 13C NMR and bioinformatics was established to expedite the discovery of acetylenic meroterpenoids from the ascidian-derived fungus Amphichorda felina SYSU-MS7908. This approach led to the identification of 13 acetylenic meroterpenoids (1-13) and four biogenic analogs (14-17), including five new ones named felinoids A-E (1-4 and 15). Their structures and absolute configurations were elucidated using extensive spectroscopy, ECD quantum chemical calculations, and single-crystal X-ray diffraction analysis. Compound 1 possessed a rare cyclic carbonate in natural acetylenic meroterpenoids. The plausible shikimate-terpenoid biosynthetic pathways of 1-4 were also postulated. Five of these isolates exhibited anti-inflammatory activity by inhibiting NO production in LPS-induced RAW264.7 cells (IC50 = 11.6-19.5 µM). Moreover, oxirapentyn E diacetate showed a dose-dependent inhibition of pro-inflammatory cytokines IL-6 and TNF-α. Structural modification of oxirapentyn B yielded 29 new derivatives, among which seven showed improved activity (IC50 < 3 µM) and higher selectivity index (SI > 22). The structure-activity relationship study indicated that 7, 8-epoxy, and 6-acylation were crucial for the activity. These findings may provide a powerful tool to accelerate the discovery of new fungal acetylenic meroterpenoids for future anti-inflammatory drug development.


Asunto(s)
Acetileno , Urocordados , Animales , Estructura Molecular , Alquinos , Terpenos/química , Antiinflamatorios/química , Espectroscopía de Resonancia Magnética , Hongos
4.
Bioorg Chem ; 136: 106542, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37087848

RESUMEN

Two new cyclopropane derivatives (1-2) and seven undescribed α-pyrone derivatives (3-9), along with one known congener (10) were obtained from the marine fungus Stagonospora sp. SYSU-MS7888, which was isolated from the South China Sea. Their planar structures were established through extensive spectroscopic analyses including 1D and 2D NMR and HR-ESIMS. The absolute configurations were identified on basis of the quantum chemical calculations of ECD and NMR, as well as the modified Mosher's method. It's particularly noteworthy that the tetrasubstituted furopyrans, chenopodolans A-F, possessing phytotoxicity and zootoxicity, were structural misassignments. The structures of chenopodolans featuring with furopyran skeleton were revised as common trisubstituted α-pyrones by computational chemistry, NMR spectroscopic method, and empirical rule. Compounds 1, 2, 7, and 9 showed significant anti-inflammatory activity with IC50 values ranging from 3.6 to 22.8 µM, which is better than the positive control indomethacin (IC50 = 26.5 ± 1.13 µM). This discovery holds potential for the development of new anti-inflammatory agents.


Asunto(s)
Ascomicetos , Pironas , Pironas/farmacología , Pironas/química , Estructura Molecular , Ascomicetos/química , Espectroscopía de Resonancia Magnética , Antiinflamatorios , Ciclopropanos
5.
Chem Biodivers ; 20(7): e202300424, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37278253

RESUMEN

One new cyclohexenone derivative (1), and two undescribed drimane sesquiterpenes (2 and 3), together with another seven known drimane sesquiterpenes were isolated from a seagrass-derived fungus Aspergillus insuetus SYSU6925. Structures of these metabolites were elucidated by comprehensive spectroscopic analysis, including NMR analysis, mass spectrometry, and ECD calculations. Compounds 1-3, 5 and 7 displayed weak to moderate antifungal activities towards four phytopathogenic fungi, with Minimum inhibition concentration (MIC) values range from 50 to 200 µg/mL. Compound 1, a rare cyclohexenone derivative with n-propyl group exhibited more potent inhibitory activities (MIC, 50 µg/mL) against F. oxysporum than positive control (Triadimefon). Compounds 2 and 3 also exhibit potent anti-inflammatory activities by inhibiting the production of nitric oxide (NO) in RAW264.7 cells with IC50 values of 21.5±1.1 and 32.6±1.16 µM, respectively.


Asunto(s)
Sesquiterpenos , Hongos , Espectroscopía de Resonancia Magnética , Estructura Molecular , Sesquiterpenos/química , Ciclohexanonas/química
6.
Mar Drugs ; 20(1)2022 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-35049907

RESUMEN

Seven new xanthones, diaporthones A-G (1-7), together with 13 known analogues, including five mono- (8-14) and six dimeric xanthones (15-20), were obtained from the ascidian-derived fungus Diaporthe sp. SYSU-MS4722. Their planar structures were established by extensive spectroscopic analyses, including 1D and 2D NMR and high-resolution mass spectrometry (HR-ESIMS). The absolute configurations of 1-7 were clearly identified by X-ray crystallographic analysis and calculation of the ECD Spectra. Compounds 15-20 showed significant anti-inflammatory activity with IC50 values between 6.3 and 8.0 µM. In addition, dimeric xanthones (15-20) showed selective cytotoxicity against T98G cell lines with IC50 values ranging from 19.5 to 78.0 µM.


Asunto(s)
Antiinflamatorios/farmacología , Antineoplásicos/farmacología , Hongos , Urocordados , Xantonas/farmacología , Animales , Antiinflamatorios/química , Antineoplásicos/química , Organismos Acuáticos , Línea Celular Tumoral/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Cristalografía por Rayos X , Glioma/patología , Humanos , Concentración 50 Inhibidora , Espectroscopía de Resonancia Magnética , Ratones , Células RAW 264.7 , Relación Estructura-Actividad , Xantonas/química
7.
Mar Drugs ; 20(5)2022 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-35621945

RESUMEN

Culturing ascidian-derived fungus Amphichorda felina SYSU-MS7908 under standard laboratory conditions mainly yielded meroterpenoid, and nonribosomal peptide-type natural products. We sequenced the genome of Amphichorda felina SYSU-MS7908 and found 56 biosynthetic gene clusters (BGCs) after bioinformatics analysis, suggesting that the majority of those BGCSs are silent. Here we report our genome mining effort on one cryptic BGC by heterologous expression in Aspergillus oryzae NSAR1, and the identification of two new α-pyrone derivatives, amphichopyrone A (1) and B (2), along with a known compound, udagawanone A (3). Anti-inflammatory activities were performed, and amphichopyrone A (1) and B (2) displayed potent anti-inflammatory activity by inhibiting nitric oxide (NO) production in RAW264.7 cells with IC50 values 18.09 ± 4.83 and 7.18 ± 0.93 µM, respectively.


Asunto(s)
Beauveria , Productos Biológicos , Urocordados , Animales , Beauveria/metabolismo , Productos Biológicos/metabolismo , Productos Biológicos/farmacología , Pironas/farmacología , Urocordados/genética , Urocordados/metabolismo
8.
Molecules ; 27(16)2022 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-36014315

RESUMEN

Amphichoterpenoids D (1) and E (2), two new picoline-derived meroterpenoids with a rare 6/6/6 tricyclic pyrano[3,2-c]pyridinyl-γ-pyranone scaffold, were isolated from the ascidian-derived fungus Amphichorda felina SYSU-MS7908. Their structures, including the absolute configurations, were established by extensive spectroscopic methods (1D and 2D NMR and high-resolution mass spectrometry) and ECD calculations. Compounds 1 and 2 showed anti-acetylcholinesterase (anti-AChE) activities with IC50 values of 12.5 µM and 11.6 µM, respectively. The binding interactions between 1, 2, and AChE were investigated using molecular docking analyses.


Asunto(s)
Beauveria , Urocordados , Animales , Espectroscopía de Resonancia Magnética , Simulación del Acoplamiento Molecular , Estructura Molecular , Picolinas , Terpenos/química
9.
Bioorg Chem ; 115: 105156, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34314917

RESUMEN

Under guidance of 1H NMR, ten new polypropionate derivatives, decempyrones A-J (1-10) along with two known analogues (11 and 12), were isolated from the marine-derived fungusFusarium decemcellulare SYSU-MS6716. The planar structures were elucidated on the basis of extensive spectroscopic analyses (1D and 2D NMR, and HR-ESIMS). The absolute configuration of the chiral centers in the side chain is a major obstacle for the structure identification of natural polypropionate derivatives. Herein, the J-based configurational analysis (JBCA), chemical degradation, geminal proton rule, and the modified Mosher's method were adopted to fix their absolute configurations in the side chain. Compounds 3 and 10 exhibited potent anti-inflammatory activity by inhibiting the production of NO in RAW264.7 cells activated by lipopolysaccharide with IC50values 22.4 ± 1.8 and 21.7 ± 1.1 µM. In addition, compounds 3 and 10 displayed MptpA inhibitory activity with an IC50 value of 19.2 ± 0.9 and 33.1 ± 2.9 µM. Structure-activity relationships of the polypropionate derivatives were discussed.


Asunto(s)
Antiinflamatorios/química , Propionatos/química , Proteínas Tirosina Fosfatasas/antagonistas & inhibidores , Animales , Antiinflamatorios/aislamiento & purificación , Antiinflamatorios/farmacología , Proteínas Bacterianas/antagonistas & inhibidores , Proteínas Bacterianas/metabolismo , Fusarium/química , Fusarium/metabolismo , Lipopolisacáridos/farmacología , Macrófagos/citología , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Espectroscopía de Resonancia Magnética , Ratones , Conformación Molecular , Óxido Nítrico/metabolismo , Propionatos/aislamiento & purificación , Propionatos/farmacología , Proteínas Tirosina Fosfatasas/metabolismo , Células RAW 264.7
10.
Clin Rehabil ; 35(7): 999-1010, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33517744

RESUMEN

OBJECTIVE: The aim of the study was to investigate whether liuzijue qigong could improve the ability of respiratory control and comprehensive speech in patients with stroke dysarthria. DESIGN: A randomized controlled trial. SETTING: The research was carried out in the department of rehabilitation. PARTICIPANTS: Altogether, a total of 98 stroke patients with dysarthria participated in the study. INTERVENTIONS: Patients were randomly divided into two groups (the experimental group: basic articulation + liuzijue qigong, 48 patients or the control group: basic articulation + traditional breathing training, 50 patients). All therapies were conducted once a day, five times a week for three weeks. MAIN MEASURES: Primary outcome measure: Speech breathing level of the modified Frenchay Dysarthria Assessment. Secondary outcome measures: the modified Frenchay Dysarthria Assessment, maximum phonation time, maximal counting ability, /s/, /z/, s/z ratio, and the loudness level. All outcome measures were assessed twice (at baseline and after three weeks). RESULTS: At three weeks, There were significant difference between the two groups in the change of speech breathing level (81% vs 66%, P = 0.011), the modified Frenchay Dysarthria Assessment (5.54 (4.68-6.40) vs 3.66 (2.92-4.40), P = 0.001), maximum phonation time (5.55 (4.92-6.18) vs 3.01(2.31-3.71), P < 0.01), maximal counting ability (3.08(2.45-3.71) vs 2.10 (1.53-2.67), P = 0.018), and /s/ (3.08 (2.39-3.78) vs 1.87 (1.23-2.51), P = 0.004), while no significant differences were found in the change of /z/ (3.08 (2.31-3.86) vs 2.10 (1.5-2.64), P = 0.08), s/z ratio (1.26 (0.96-1.55) vs 1.03 (0.97-1.09), P = 0.714), and the change of loudness level (69% vs 60%, P = 0.562). CONCLUSIONS: Liuzijue qigong, combined with basic articulation training, could improve the respiratory control ability, as well as the comprehensive speech ability of stroke patients with dysarthria. TRIAL REGISTRATION: ChiCTR-INR-16010215.


Asunto(s)
Ejercicios Respiratorios , Disartria/rehabilitación , Qigong , Anciano , Disartria/etiología , Femenino , Humanos , Masculino , Fonación , Accidente Cerebrovascular/complicaciones , Rehabilitación de Accidente Cerebrovascular/métodos
11.
Mar Drugs ; 19(6)2021 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-34070447

RESUMEN

Six new fusarin derivatives, fusarins G-L (1-6), together with five known compounds (5-11) were isolated from the marine-derived fungus Fusarium solani 7227. The structures of the new compounds were elucidated by means of comprehensive spectroscopic methods (1D and 2D NMR, HRESIMS, ECD, and ORC) and X-ray crystallography. Compounds 5-11 exhibited potent anti-inflammatory activity by inhibiting the production of NO in RAW264.7 cells activated by lipopolysaccharide, with IC50 values ranging from 3.6 to 32.2 µM. The structure-activity relationships of the fusarins are discussed herein.


Asunto(s)
Antiinflamatorios/farmacología , Fusarium , Lactamas/farmacología , Óxido Nítrico/antagonistas & inhibidores , Polienos/farmacología , Animales , Antiinflamatorios/aislamiento & purificación , Fermentación , Fusarium/química , Fusarium/metabolismo , Lactamas/aislamiento & purificación , Lipopolisacáridos/farmacología , Ratones , Óxido Nítrico/metabolismo , Polienos/aislamiento & purificación , Células RAW 264.7 , Metabolismo Secundario , Relación Estructura-Actividad
12.
Environ Monit Assess ; 187(5): 232, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25850993

RESUMEN

To estimate the distribution and sources of polycyclic aromatic hydrocarbons (PAHs) in the soils of Baise, in southwest China, soil sampling sites were selected from industry, traffic, rubbish, gas station, residential, and suburban areas for analysis of PAHs. The average concentrations of ∑16PAHs in the present study varied significantly, depending on the sampling location, and ranged from 16.8 to 6,437.0 µg/kg (dry weight basis), with a mean value of 565.8 µg/kg. PAH concentrations decreased significantly along the industry-traffic-rubbish-gas station-residential-suburban transect. The PAH profiles in the surface soil of the different areas imply that either source proximity to the sampling sites, or transport and deposition effects influenced PAH distributions. Two diagnostic ratios were selected and used to apportion PAH sources in the surface soil, and bivariate plots show general trends of covariation. Principal component analysis and multivariate linear regression were used to determine the primary sources and their contributions of PAHs to the soils. The model showed that factors 1 (coal and wood combustion) and 2 (petroleum combustion) contributed over 52.1 and 32.5% of the total source of soil PAHs, respectively. The remaining 15.4% came from evaporative and uncombusted petroleum.


Asunto(s)
Monitoreo del Ambiente , Hidrocarburos Policíclicos Aromáticos/análisis , Contaminantes del Suelo/análisis , Suelo/química , China , Carbón Mineral/análisis , Petróleo/análisis , Análisis de Componente Principal , Madera/química
13.
J Environ Qual ; 43(6): 1942-52, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25602211

RESUMEN

Several studies have investigated the distribution patterns and geographic sources of polycyclic aromatic hydrocarbons (PAHs) in mountainous areas. Little is known about how different sources contribute to PAH concentrations at different elevations along mountain slopes. To estimate the distribution and sources of PAHs at different altitudes in mountainous areas of southwestern China, samples of soils and leaves from trees were collected from 1000 to 1500 m asl in the Dawangling forest and analyzed for PAHs. Total PAH concentrations ranged from 93.9 to 802.3 ng g (average, 252.3 ng g) in soils and from 4.1 to 100.9 ng g (average, 23.1 ng g) in leaves. Our results suggest that soil PAH levels in the study area could be classified as "weakly contaminated." The PAH levels in leaves from the Dawangling forest were lower than those found in Himalayan spruce needles from the central Himalayas in China and from an agricultural station in southern England. Total PAHs in the Dawangling forest soils increased with elevation, primarily due to the low-molecular-weight PAHs, which accumulated in samples from higher altitudes. In contrast, high-molecular-weight PAHs were inversely related to or unrelated to elevation. The PAH profiles were similar in soils and leaves from all mountainous regions. Diagnostic ratios showed that the PAHs in soils at different altitudes were from different pollution emission sources; therefore, PAHs in the entire study area were probably derived from mixed sources. Cluster analyses confirmed that liquefied petroleum gas, coal/wood combustion, and petroleum combustion were likely the predominant PAH sources in this region.

14.
Nanomaterials (Basel) ; 14(5)2024 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-38470776

RESUMEN

The band gap is a key parameter in semiconductor materials that is essential for advancing optoelectronic device development. Accurately predicting band gaps of materials at low cost is a significant challenge in materials science. Although many machine learning (ML) models for band gap prediction already exist, they often suffer from low interpretability and lack theoretical support from a physical perspective. In this study, we address these challenges by using a combination of traditional ML algorithms and the 'white-box' sure independence screening and sparsifying operator (SISSO) approach. Specifically, we enhance the interpretability and accuracy of band gap predictions for binary semiconductors by integrating the importance rankings of support vector regression (SVR), random forests (RF), and gradient boosting decision trees (GBDT) with SISSO models. Our model uses only the intrinsic features of the constituent elements and their band gaps calculated using the Perdew-Burke-Ernzerhof method, significantly reducing computational demands. We have applied our model to predict the band gaps of 1208 theoretically stable binary compounds. Importantly, the model highlights the critical role of electronegativity in determining material band gaps. This insight not only enriches our understanding of the physical principles underlying band gap prediction but also underscores the potential of our approach in guiding the synthesis of new and valuable semiconductor materials.

15.
ISA Trans ; 146: 29-41, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38104021

RESUMEN

The uncertainty in mobile robot greatly affects control accuracy. This makes it difficult to apply to more rigorous high-precision engineering fields. Therefore, the fuzzy set theory is introduced to describe the uncertainty. Based on that, the fuzzy mobile robot system is established. The virtual speed controller using backstepping method is designed. Then, a robust control method is proposed to guarantee the uniform boundedness and uniform ultimate boundedness of the controlled system. Furthermore, the balance optimization problem of the performance and cost of the controlled system is explored. By minimizing the performance index containing fuzzy numbers, the optimal control parameter is obtained. Compared with the linear quadratic regulator algorithm, which is the representative optimal robust controller, the proposed control method and optimization strategy based on fuzzy set theory are verified to be effective. The control accuracy is further improved.

16.
Rev Sci Instrum ; 95(2)2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38421259

RESUMEN

The sharpening switch is one of the most important elements in the trigger generator, which is used to sharpen the front of the trigger pulse. The breakdown performance of the sharpening switch has an important influence on the output and stability of the trigger generator. In this paper, a novel 200 kV capacitance-coupling pre-ionized sharpening switch, which can realize pre-ionization by dividing voltage through its own structural capacitances, is proposed and investigated. In order to obtain the optimal parameters of the pre-ionized sharpening switch, the influences of the electrode structure, electrode material, main gap distance, and pre-ionized gap distance on the breakdown performance are studied experimentally. The experimental results show that the electrode structure with a circular knife-edged cathode and a plate-shaped anode has the smallest breakdown jitter, followed by the needle-plate structure and the tapered ball-head structure. The stainless steel electrode has the smallest jitter, followed by graphite, aluminum, and brass electrodes. When the gap distances of the main gap and the pre-ionized gap are 13 and 1.5 mm, respectively, the breakdown stability of the pre-ionized sharpening switch is the best. Under an input voltage pulse with a rise time of about one microsecond, the jitter of the capacitance-coupling pre-ionized sharpening switch with the optimal parameters is 6.08 ns, which is about 0.6% of the rise time of the input pulse. The jitter decreases by 44.5% compared to the switch without pre-ionization. The rise time of the output pulse is sharpened to 17 ns, corresponding to a voltage rise rate of more than 11 kV/ns.

17.
Poult Sci ; 103(9): 103929, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38943802

RESUMEN

This study aimed to investigate the developmental change of body growth and gene expression related to fatty acid uptake and oxidation in the yolk sac membrane (YSM) and jejunum during embryogenesis in Muscovy ducks. The weights of embryos and yolk sac (YS) (5 embryos per replicate, n = 6) were recorded on embryonic days (E)16, E19, E22, E25, E28, E31, and the day of hatch (DOH). The fat and fatty acid contents in YSM, jejunal histology, and gene expression related to fatty acid metabolism in YSM and jejunum were determined in each sampling time. Among the nonlinear models, the maximum growth is estimated at 2.83 (E22.5), 2.67 (E22.1), and 2.60 (E21.3) g/d using logistic, Gompertz, and Von Bertalanffy models, respectively. The weight of YS, and ether extract-free YS as well as the amounts of fat and fatty acids in YS decreased (P < 0.05) linearly, whereas the villus height, crypt depth, villus height/crypt depth, and musculature thickness in jejunum increased (P < 0.05) linearly during embryogenesis. The mRNA expression of CD36, SLC27A4, and FABP1 related to fatty acid uptake as well as the mRNA and protein expressions of PPARα and CPT1 related to fatty acid oxidation increased in a quadratic manner (P < 0.05) in both YS and jejunum, and the maximum values were achieved during E25 to E28. In conclusion, the maximum growth rate of Muscovy duck embryos was estimated at 2.60 to 2.83 g/d on E21.3 to E23.5, while the accumulations of lipid and fatty acid in YS were decreased in association with the increased absorptive area of morphological structures in jejunum. The gene and protein expression involved in fatty acid metabolism displayed a similar enhancement pattern between YSM and jejunum during E25 to E28, suggesting that fatty acid utilization could be strengthened to meet the energy demand for embryonic development.

18.
PeerJ Comput Sci ; 9: e1338, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37346524

RESUMEN

In recent years, recommendation systems have already played a significant role in major streaming video platforms.The probabilistic matrix factorization (PMF) model has advantages in addressing high-dimension problems and rating data sparsity in the recommendation system. However, in practical application, PMF has poor generalization ability and low prediction accuracy. For this reason, this article proposes the Hybrid AdaBoost Ensemble Method. Firstly, we use the membership function and the cluster center selection in fuzzy clustering to calculate the scoring matrix of the user-items. Secondly, the clustering user items' scoring matrix is trained by the neural network to improve the scoring prediction accuracy further. Finally, with the stability of the model, the AdaBoost integration method is introduced, and the score matrix is used as the base learner; then, the base learner is trained by different neural networks, and finally, the score prediction is obtained by voting results. In this article, we compare and analyze the performance of the proposed model on the MovieLens and FilmTrust datasets. In comparison with the PMF, FCM-PMF, Bagging-BP-PMF, and AdaBoost-SVM-PMF models, several experiments show that the mean absolute error of the proposed model increases by 1.24% and 0.79% compared with Bagging-BP-PMF model on two different datasets, and the root-mean-square error increases by 2.55% and 1.87% respectively. Finally, we introduce the weights of different neural network training based learners to improve the stability of the model's score prediction, which also proves the method's universality.

19.
JMIR Aging ; 6: e50037, 2023 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-37962517

RESUMEN

Background: Various older adult care settings have embraced the use of the life story approach to enhance the development of comprehensive care plans. However, organizing life stories and extracting useful information is labor-intensive, primarily due to the repetitive, fragmented, and redundant nature of life stories gathered from everyday communication scenarios. Existing life story systems, while available, do not adequately fulfill the requirements of users, especially in the application of care services. Objective: The objective of this study is to design, develop, and evaluate a digital system that provides caregivers with the necessary tools to view and manage the life stories of older adults, enabling expedited access to pertinent information effectively and visually. Methods: This study used a multidisciplinary, user-centered design approach across 4 phases: initial design requirements, prototyping, prototype refinement workshops, and usability testing. During the initial phase, we conducted field research in the Hefei Tianyu Senior Living Service Nursing Home, China, to discover how caregivers currently store and use life stories and their needs, challenges, and obstacles in organizing and retrieving information. Subsequently, we designed a low-fidelity prototype according to the users' requirements. A prototyping workshop involving 6 participants was held to collaboratively design and discuss the prototype's function and interaction. User feedback from the workshops was used to optimize the prototype, leading to the development of the system. We then designed 2 rounds of usability testing with 7 caregivers to evaluate the system's usability and effectiveness. Results: We identified 3 categories of functionalities that are necessary to include in the design of our initial low-fidelity prototype of life story visualizations: life story input, life story organization, and timeline generation. Subsequently, through the workshops, we identified 3 categories for functional optimization: feedback on user interface and usability, optimization suggestions for existing features, and the request for additional functionalities. Next, we designed a medium-fidelity prototype based on human-centered design. The Story Mosaic system underwent usability testing in the Hefei Tianyu Senior Living Service Nursing Home. Overall, 7 users recorded and organized 1123 life stories of 16 older adults. The usability testing results indicated that the system was accessible and easy to use for caregivers. Based on the feedback from the usability testing, we finalized the high-fidelity prototype. Conclusions: We designed, developed, and evaluated the Story Mosaic system to support the visual management of older adults' life stories. This system empowers caregivers through digital technology and innovative design, pioneering personal narrative integration in caregiving. This system can expand to include informal caregivers and family members for continued adaptability and empathy.

20.
Polymers (Basel) ; 15(5)2023 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-36904424

RESUMEN

Preparing flame-retardant polyamide 66 (PA66) fibers through melt spinning remains one of the biggest challenges nowadays. In this work, dipentaerythritol (Di-PE), an eco-friendly flame retardant, was blended into PA66 to prepare PA66/Di-PE composites and fibers. It was confirmed that Di-PE could significantly improve the flame-retardant properties of PA66 by blocking the terminal carboxyl groups, which was conducive to the formation of a continuous and compact char layer and the reduced production of combustible gas. The combustion results of the composites showed that the limiting oxygen index (LOI) increased from 23.5% to 29.4%, and underwriter laboratories 94 (UL-94) passed the V-0 grade. The peak of heat release rate (PHRR), total heat release (THR), and total smoke production (TSP) decreased by 47.3%, 47.8%, and 44.8%, respectively, for the PA66/6 wt% Di-PE composite compared to those recorded for pure PA66. More importantly, the PA66/Di-PE composites possessed excellent spinnability. The prepared fibers still had good mechanical properties (tensile strength: 5.7 ± 0.2 cN/dtex), while maintaining good flame-retardant properties (LOI: 28.6%). This study provides an outstanding industrial production strategy for fabricating flame-retardant PA66 plastics and fibers.

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