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1.
J Mol Graph Model ; 130: 108790, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38749235

RESUMEN

At present, the hydrogen evolution reaction (HER) of Ni-based electrode has an important influence on water electrolysis hydrogen production technology, involving complex electrochemical process of electrode. In this project, Materials Studio (MS) software was used to design and construct Ni-based electrode surface (NES) models with monatomic Mo, Co, Fe, Cr doping, and the NES models attached 1 H atom and 2H atoms were denoted as the NES-H models and NES-2H model, respectively. Then the first-principles calculation was carried out. The results showed that the doping of different atoms can effectively change the work function of the pure Ni. In the charge transfer process of the four NES-2H models, the distance between the two H atoms is most affected by Mo doping, and they leave the Ni electrode surface as a single H ion, respectively, while the effect on Co, Fe and Cr doping is relatively consistent, and they leave the Ni electrode surface with H2 molecules, respectively. The doping of four single atoms changes the distance of valence band (VB) top and conduction band (CB) bottom from Fermi level in NES, NES-H and NES-2H models, and affects the HER, in which Mo doping has the greatest effect. The TDOS of the above models is mainly derived from the PDOS of the d orbitals of the doped atoms and Ni atoms. The results will provide a theoretical basis for the research and development of Ni-based electrode materials in HER.


Asunto(s)
Electrodos , Hidrógeno , Níquel , Hidrógeno/química , Níquel/química , Propiedades de Superficie , Electrones , Modelos Moleculares
2.
Org Biomol Chem ; 22(16): 3204-3208, 2024 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-38563260

RESUMEN

An efficient palladium-catalyzed [2 + 2 + 1] annulation of 3-iodochromones, bridged olefins, and iodomethane is described, affording a range of chromone-containing polycyclic compounds. Additionally, the corresponding deuterated products were smoothly obtained with iodomethane-d3 instead of iodomethane. Moreover, the synthetic utility of this method is further substantiated by gram scale preparation and application to late-stage modification of estrone.

3.
Sensors (Basel) ; 23(6)2023 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-36992056

RESUMEN

The passive optical network (PON) is widely used in optical fiber communication thanks to its low cost and low resource consumption. However, the passiveness brings about a critical problem that it requires manual work to identify the topology structure, which is costly and prone to bringing noise to the topology logs. In this paper, we provide a base solution firstly introducing neural networks for such problems, and based on that solution we propose a complete methodology (PT-Predictor) for predicting PON topology through representation learning on its optical power data. Specifically, we design useful model ensembles (GCE-Scorer) to extract the features of optical power with noise-tolerant training techniques integrated. We further implement a data-based aggregation algorithm (MaxMeanVoter) and a novel Transformer-based voter (TransVoter) to predict the topology. Compared with previous model-free methods, PT-Predictor is able to improve prediction accuracy by 23.1% in scenarios where data provided by telecom operators is sufficient, and by 14.8% in scenarios where data is temporarily insufficient. Besides, we identify a class of scenarios where PON topology does not follow a strict tree structure, and thus topology prediction cannot be effectively performed by relying on optical power data alone, which will be studied in our future work.

4.
J Tissue Eng ; 13: 20417314221122123, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36093432

RESUMEN

To study the biological functions and applications of human amniotic epithelial cell-derived extracellular vesicles (hAEC-EVs), the cargos of hAEC-EVs were analyzed using miRNA sequencing and proteomics analysis. The hAECs and hAEC-EVs in this study had specific characteristics. Multi-omics analyses showed that extracellular matrix (ECM) reorganization, inhibition of excessive myofibroblasts, and promotion of target cell adhesion to the ECM were their primary functions. We evaluated the application of hAEC-EVs for corneal alkali burn healing in rabbits and elucidated the fundamental mechanisms. Slit-lamp images revealed that corneal alkali burns induced central epithelial loss, stromal haze, iris, and pupil obscurity in rabbits. Slit-lamp examination and histological findings indicated that hAEC-EVs facilitated re-epithelialization of the cornea after alkali burns, reduced scar formation and promoted the restoration of corneal tissue transparency. Significantly fewer α-SMA-positive myofibroblasts were observed in the hAEC-EV-treated group than the PBS group. HAEC-EVs effectively promoted the proliferation and migration of hCECs and hCSCs in vitro and activated the focal adhesion signaling pathway. We demonstrated that hAEC-EVs were excellent cell-free candidates for the treatment of ECM lesion-based diseases, including corneal alkali burns. HAEC-EVs promoted ECM reorganization and cell adhesion of target tissues or cells via orderly activation of the focal adhesion signaling pathway.

5.
Front Psychol ; 12: 769487, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-35046873

RESUMEN

The present study examined the effect of residential mobility on impression formation. In the study, participants were first engaged in a residential mobility priming task where they were asked to imagine and describe either frequent moving life (high-mobility condition) or less frequent moving life (low-mobility condition). They then evaluated their attitudes toward four types of target persons: competent vs. incompetent and warm vs. cold. As a result, in the high-mobility condition, the effect of competence was observed only when participants evaluated a warm person, whereas in the low-mobility condition, it appeared only when participants evaluated a cold person. The potential influence of individual residential mobility on the relationship formation is also discussed.

6.
J Ethnopharmacol ; 248: 112319, 2020 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-31639488

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Apoptosis plays an important role in cerebral ischemia-reperfusion injury and triggers a series of pathological changes which may even be life-threatening. Astragaloside-IV (AS-IV), a natural compound extracted from Astragalus (Astragalus membranaceus (Fisch.) Bunge., Leguminosae, Huangqi in Chinese), showed neuroprotective effects in the study of cerebral ischemia-reperfusion injury. In this study we investigate the effects of AS-IV on apoptosis induced by transient cerebral ischemia and reperfusion in rats, as well as the associated regulatory factors. METHODS: AS-IV was administrated to male Sprague-Dawley (SD) rats after transient cerebral ischemia and reperfusion surgery (12.5, 25, and 50 mg/kg, once per day, continued for 7 days after surgey). After seven days of continuous administration, neurological function, cerebral infarction volume, and pathological changes of brain tissue were detected. Fas, FasL, Caspase-8, Bax, and Bcl-2 mRNA levels were determined by real-time PCR. Caspase-8, Bid, Cytochrome C (Cyto C), cleaved Caspase-3 proteins were determined by western blot and immunohistochemistry was used to quantify Cyto C. RESULTS: AS-IV significantly attenuated the neurological deficit in rats with ischemica-reperfusion injury, and reduced cerebral infarction and neuronal apoptosis. AS-IV inhibited the mRNA upregulation of Fas, FasL, Caspase-8, and Bax/Bcl-2. Furthermore, the protein level of apoptosis cytokines Caspase-8, Bid, cleaved Caspase-3 and Cyto C were also inhibited after ischemia reperfusion, suggesting that AS-IV might alleviate ischemia reperfusion-induced apoptosis by inhibiting the activation of key factors in death receptor pathway and mitochondrial pathway.


Asunto(s)
Proteínas Reguladoras de la Apoptosis/metabolismo , Apoptosis/efectos de los fármacos , Infarto Encefálico/prevención & control , Encéfalo/efectos de los fármacos , Mitocondrias/efectos de los fármacos , Fármacos Neuroprotectores/farmacología , Receptores de Muerte Celular/metabolismo , Daño por Reperfusión/prevención & control , Saponinas/farmacología , Triterpenos/farmacología , Animales , Proteínas Reguladoras de la Apoptosis/genética , Encéfalo/metabolismo , Encéfalo/patología , Infarto Encefálico/genética , Infarto Encefálico/metabolismo , Infarto Encefálico/patología , Modelos Animales de Enfermedad , Masculino , Mitocondrias/metabolismo , Mitocondrias/patología , Ratas Sprague-Dawley , Receptores de Muerte Celular/genética , Daño por Reperfusión/genética , Daño por Reperfusión/metabolismo , Daño por Reperfusión/patología , Transducción de Señal
7.
JMIR Mhealth Uhealth ; 7(4): e11959, 2019 04 23.
Artículo en Inglés | MEDLINE | ID: mdl-31012863

RESUMEN

BACKGROUND: We should pay more attention to the long-term monitoring and early warning of type 2 diabetes and its complications. The traditional blood glucose tests are traumatic and cannot effectively monitor the development of diabetic complications. The development of mobile health is changing rapidly. Therefore, we are interested in developing a new noninvasive, economical, and instant-result method to accurately diagnose and monitor type 2 diabetes and its complications. OBJECTIVE: We aimed to determine whether type 2 diabetes and its complications, including hypertension and hyperlipidemia, could be diagnosed and monitored by using pulse wave. METHODS: We collected the pulse wave parameters from 50 healthy people, 139 diabetic patients without hypertension and hyperlipidemia, 133 diabetic patients with hypertension, 70 diabetic patients with hyperlipidemia, and 75 diabetic patients with hypertension and hyperlipidemia. The pulse wave parameters showing significant differences among these groups were identified. Various machine learning models such as linear discriminant analysis, support vector machines (SVMs), and random forests were applied to classify the control group, diabetic patients, and diabetic patients with complications. RESULTS: There were significant differences in several pulse wave parameters among the 5 groups. The parameters height of tidal wave (h3), time distance between the start point of pulse wave and dominant wave (t1), and width of percussion wave in its one-third height position (W) increase and the height of dicrotic wave (h5) decreases when people develop diabetes. The parameters height of dominant wave (h1), h3, and height of dicrotic notch (h4) are found to be higher in diabetic patients with hypertension, whereas h5 is lower in diabetic patients with hyperlipidemia. For detecting diabetes, the method with the highest out-of-sample prediction accuracy is SVM with polynomial kernel. The algorithm can detect diabetes with 96.35% accuracy. However, all the algorithms have a low accuracy when predicting diabetic patients with hypertension and hyperlipidemia (below 70%). CONCLUSIONS: The results demonstrated that the noninvasive and convenient pulse-taking diagnosis described in this paper has the potential to become a low-cost and accurate method to monitor the development of diabetes. We are collecting more data to improve the accuracy for detecting hypertension and hyperlipidemia among diabetic patients. Mobile devices such as sport bands, smart watches, and other diagnostic tools are being developed based on the pulse wave method to improve the diagnosis and monitoring of diabetes, hypertension, and hyperlipidemia.


Asunto(s)
Diabetes Mellitus Tipo 2/diagnóstico , Análisis de la Onda del Pulso/normas , Algoritmos , Análisis de Varianza , Estudios de Casos y Controles , China , Diabetes Mellitus Tipo 2/fisiopatología , Dislipidemias/diagnóstico , Dislipidemias/fisiopatología , Femenino , Humanos , Hipertensión/diagnóstico , Hipertensión/fisiopatología , Aprendizaje Automático/normas , Aprendizaje Automático/estadística & datos numéricos , Masculino , Persona de Mediana Edad , Análisis de la Onda del Pulso/instrumentación , Análisis de la Onda del Pulso/métodos , Estadísticas no Paramétricas
8.
Biomed Res Int ; 2018: 3128378, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30426006

RESUMEN

Acupoint therapy is one of the therapeutic means in Traditional Chinese Medicine (TCM) concerning acupoints and meridians, including manual acupuncture, electroacupuncture, moxibustion, external application, acupoint injection, and catgut embedding. In the treatment of diabetes and its common chronic complications, acupoint therapy has proved to have specific curative effect and notable advantages. Single or combined with western medicine, it has superior efficacy and less side effects than western medicine alone. Studying its mechanism can provide experimental basis for clinical treatment. Relevant researches in the recent 5 years mainly focused on the mechanism of electroacupuncture, point injection, catgut embedding, etc. in the treatment of diabetes and common diabetic complications such as neuropathy, nephropathy, and hepatopathy. The possible theories involve the regulation of nerve conduction, signal pathways, hormone level, protein expression, oxidative stress level, structure restoration, etc. The most studied acupoints are Zusanli (ST36), Shenshu (BL23), Sanyinjiao (SP6), Yishu (EX-B3), and Zhongwan (CV12). However, most of the studies have been based on diabetes model rats rather than clinical trials. Moreover, the mechanism of acupoint therapy treating other chronic complications like diabetic retinopathy and that of other effective methods like pressing ear with beans, auricular points plaster therapy, and external application remain unclear. Therefore, this aspect still awaits further research.


Asunto(s)
Puntos de Acupuntura , Diabetes Mellitus Experimental , Hormonas/metabolismo , Biosíntesis de Proteínas , Transducción de Señal , Animales , Enfermedad Crónica , Complicaciones de la Diabetes/metabolismo , Complicaciones de la Diabetes/patología , Complicaciones de la Diabetes/fisiopatología , Complicaciones de la Diabetes/terapia , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/fisiopatología , Diabetes Mellitus Experimental/terapia , Humanos , Ratas
9.
Zhongguo Zhong Yao Za Zhi ; 43(9): 1940-1945, 2018 May.
Artículo en Chino | MEDLINE | ID: mdl-29902908

RESUMEN

To investigate the pharmacokinetic characteristics of active constituents of Guhong injection in rats with cerebral ischemia reperfusion injury. The middle cerebral artery occlusion (MCAO) model was established in our studies, and then all the rats received iv administration of Guhong injection (2.1 mL·kg⁻¹). The blood concentrations of aceglutamide and hydroxysafflor yellow A (HSYA) were determined by high performance liquid chromatography (HPLC) method at different time points. The concentration-time curves were drawn and pharmacokinetic data were obtained by DAS 3.2.6 software. The results showed that aceglutamide and HSYA showed good linear relationship within the ranges of 1.5-500 mg·L⁻¹ (R²=0.997 5) and 0.33-40 mg·L⁻¹ (R²=0.998 9) respectively. This quantitative method showed a high recovery rate, good precision and stability. The main pharmacokinetics parameters of t1/2α, t1/2ß, CL1, CL2, AUC0-t, AUC0-∞, Vd1, and Vd2 were (0.139±0.007) and (0.155±0.017) h, (0.803±0.046) and (2.233±0.410) h, (0.016±0) and (0.149±0.018) L·h⁻¹·kg⁻¹, (0.015±0.001) and (0.446±0.016) L·h⁻¹·kg⁻¹, (133.335±3.844) and (9.298±0.179) mg·h·L⁻¹, (143.851±3.595) and (14.464±1.451) mg·h·L⁻¹, (0.009±0.001) and (0.223±0.007) L·kg⁻¹, (0.006±0.001) and (0.212±0.032) L·kg⁻¹, respectively. The results showed that the established HPLC method was highly specific, and could be used for the simultaneous detection of aceglutamide and HSYA of Guhong injection in MCAO rats, which was conducive to pharmacokinetic studies. Pharmacokinetic data and parameters could provide reference for continuous administration and interval administration of the drug.


Asunto(s)
Isquemia Encefálica , Infarto de la Arteria Cerebral Media , Animales , Glutamina/análogos & derivados , Extractos Vegetales , Ratas , Ratas Sprague-Dawley
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