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1.
Neuron ; 111(18): 2847-2862.e10, 2023 09 20.
Artículo en Inglés | MEDLINE | ID: mdl-37402372

RESUMEN

Alzheimer's disease (AD) is caused by a complex interaction between genetic and environmental factors. However, how the role of peripheral organ changes in response to environmental stimuli during aging in AD pathogenesis remains unknown. Hepatic soluble epoxide hydrolase (sEH) activity increases with age. Hepatic sEH manipulation bidirectionally attenuates brain amyloid-ß (Aß) burden, tauopathy, and cognitive deficits in AD mouse models. Moreover, hepatic sEH manipulation bidirectionally regulates the plasma level of 14,15-epoxyeicosatrienoic acid (-EET), which rapidly crosses the blood-brain barrier and modulates brain Aß metabolism through multiple pathways. A balance between the brain levels of 14,15-EET and Aß is essential for preventing Aß deposition. In AD models, 14,15-EET infusion mimicked the neuroprotective effects of hepatic sEH ablation at biological and behavioral levels. These results highlight the liver's key role in AD pathology, and targeting the liver-brain axis in response to environmental stimuli may constitute a promising therapeutic approach for AD prevention.


Asunto(s)
Enfermedad de Alzheimer , Animales , Ratones , Enfermedad de Alzheimer/metabolismo , Péptidos beta-Amiloides/metabolismo , Encéfalo/metabolismo , Modelos Animales de Enfermedad , Epóxido Hidrolasas/genética , Epóxido Hidrolasas/metabolismo , Hígado/metabolismo , Hígado/patología
2.
Cell ; 186(7): 1352-1368.e18, 2023 03 30.
Artículo en Inglés | MEDLINE | ID: mdl-37001500

RESUMEN

Resilience enables mental elasticity in individuals when rebounding from adversity. In this study, we identified a microcircuit and relevant molecular adaptations that play a role in natural resilience. We found that activation of parvalbumin (PV) interneurons in the primary auditory cortex (A1) by thalamic inputs from the ipsilateral medial geniculate body (MG) is essential for resilience in mice exposed to chronic social defeat stress. Early attacks during chronic social defeat stress induced short-term hyperpolarizations of MG neurons projecting to the A1 (MGA1 neurons) in resilient mice. In addition, this temporal neural plasticity of MGA1 neurons initiated synaptogenesis onto thalamic PV neurons via presynaptic BDNF-TrkB signaling in subsequent stress responses. Moreover, optogenetic mimicking of the short-term hyperpolarization of MGA1 neurons, rather than merely activating MGA1 neurons, elicited innate resilience mechanisms in response to stress and achieved sustained antidepressant-like effects in multiple animal models, representing a new strategy for targeted neuromodulation.


Asunto(s)
Corteza Auditiva , Ratones , Animales , Corteza Auditiva/metabolismo , Tálamo/fisiología , Neuronas/metabolismo , Cuerpos Geniculados , Interneuronas/fisiología , Parvalbúminas/metabolismo
3.
J Fish Biol ; 103(2): 220-234, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-36929653

RESUMEN

Probiotics are widely used in aquaculture. This article aims to study the effect of Bacillus amyloliquefaciens LSG2-8 on the intestinal barrier function of Rhynchocypris lagowskii. B. amyloliquefaciens LSG2-8 were added to R. lagowskii basal diets (CK) as additives at four concentrations: 1.0 × 106 (D-6), 1.0 × 107 (D-7), 1.0 × 108 (D-8) and 1.0 × 109 (D-9) CFU g-1 by dry weight of basal diet. After a 56-day feeding experiment, the activities of intestinal digestive enzymes and immunity-related enzymes of R. lagowskii on group D-6, D-7, D-8 and D-9 diet were significantly higher than the control (P < 0.05). In molecular experiments, the authors found that the levels of TGF-ß mRNA, IL-10 mRNA, ZO-1 mRNA and claudin-3 mRNA in group D-8 R. lagowskii were significantly higher (P < 0.05) than those of the control and other groups. Furthermore, the levels of IL-1ß and IL-8 mRNA of R. lagowskii on group D-6, D-7, D-8 and D-9 diet were significantly lower than those of the control (P < 0.05). In addition, the authors found that B. amyloliquefaciens LSG2-8 can regulate the intestinal flora balance and improve the intestinal structure of R. lagowskii. In conclusion, B. amyloliquefaciens LSG2-8 can improve the intestinal barrier function of R. lagowskii and can be used as a feed additive in aquaculture.


Asunto(s)
Bacillus amyloliquefaciens , Cyprinidae , Probióticos , Animales , Bacillus amyloliquefaciens/química , Bacillus amyloliquefaciens/fisiología , Probióticos/farmacología , Dieta/veterinaria , Cyprinidae/genética , Alimentación Animal/análisis , Suplementos Dietéticos
4.
Eur J Nucl Med Mol Imaging ; 50(3): 881-891, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36301324

RESUMEN

PURPOSE: To compare PET/CT, MRI and ultrasonography in detecting recurrence of nasopharyngeal carcinoma and identify their benefit in staging, contouring and overall survival (OS). METHODS: Cohort A included 1453 patients with or without histopathology-confirmed local recurrence, while cohort B consisted of 316 patients with 606 histopathology-confirmed lymph nodes to compare the sensitivities and specificities of PET/CT, MRI and ultrasonography using McNemar test. Cohorts C and D consisted of 273 patients from cohort A and 267 patients from cohort B, respectively, to compare the distribution of PET/CT-based and MRI-based rT-stage and rN-stage and the accuracy of rN-stage using McNemar test. Cohort E included 30 random patients from cohort A to evaluate the changes in contouring with or without PET/CT by related-samples T test or Wilcoxon rank test. The OS of 61 rT3-4N0M0 patients staged by PET/CT plus MRI (cohort F) and 67 MRI-staged rT3-4N0M0 patients (cohort G) who underwent similar salvage treatment were compared by log-rank test and Cox regression. RESULTS: PET/CT had similar specificity to MRI but higher sensitivity (93.9% vs. 79.3%, P < 0.001) in detecting local recurrence. PET/CT, MRI and ultrasonography had comparable specificities, but PET/CT had greater sensitivity than MRI (90.9% vs. 67.6%, P < 0.001) and similar sensitivity to ultrasonography in diagnosing lymph nodes. According to PET/CT, more patients were staged rT3-4 (82.8% vs. 68.1%, P < 0.001) or rN + (89.9% vs. 69.3%, P < 0.001), and the rN-stage was more accurate (90.6% vs. 73.8%, P < 0.001). Accordingly, the contours of local recurrence were more precise (median Dice similarity coefficient 0.41 vs. 0.62, P < 0.001) when aided by PET/CT plus MRI. Patients staged by PET/CT plus MRI had a higher 3-year OS than patients staged by MRI alone (85.5% vs. 60.4%, P = 0.006; adjusted HR = 0.34, P = 0.005). CONCLUSION: PET/CT more accurately detected and staged recurrence of nasopharyngeal carcinoma and accordingly complemented MRI, providing benefit in contouring and OS.


Asunto(s)
Neoplasias Nasofaríngeas , Tomografía Computarizada por Tomografía de Emisión de Positrones , Humanos , Fluorodesoxiglucosa F18 , Carcinoma Nasofaríngeo/diagnóstico por imagen , Carcinoma Nasofaríngeo/terapia , Terapia Recuperativa , Recurrencia Local de Neoplasia/diagnóstico por imagen , Recurrencia Local de Neoplasia/terapia , Recurrencia Local de Neoplasia/patología , Imagen por Resonancia Magnética , Sensibilidad y Especificidad , Neoplasias Nasofaríngeas/diagnóstico por imagen , Neoplasias Nasofaríngeas/terapia , Estadificación de Neoplasias
5.
Fish Physiol Biochem ; 48(5): 1315-1332, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36103020

RESUMEN

This study evaluated the effects of dietary administration of two indigenous Bacillus (A: basal control diet; B: 0.15 g/kg of Bacillus subtilis; C: 0.1 g/kg of Bacillus subtilis and 0.05 g/kg of Bacillus licheniformis; D: 0.05 g/kg of Bacillus subtilis and 0.1 g/kg of Bacillus licheniformis; E: 0.15 g/kg of Bacillus licheniformis) on the digestive enzyme activities, intestinal morphology, intestinal immune and barrier-related genes relative expression levels, and intestinal flora of Rhynchocypris lagowskii. The results showed that the fold height, lamina propria width, and muscle layer thickness of midgut and hindgut in group C were significantly higher than that of group A (P < 0.05). The activities of protease, amylase, and lipase in group C were significantly higher than those of group A (P < 0.05). The relative expression levels of IL-1ß and IL-8 in the intestine of group C were significantly downregulated, and the relative expression levels of IL-10 and TGF-ß were significantly upregulated (P < 0.05). The relative expression levels of Claudin-2 in group A significantly increased and the relative expression levels of Claudin-4 in group A significantly reduced compared with other groups (P < 0.05). The relative expression levels of ZO-1 in groups C and D were significantly higher than those of other groups (P < 0.05). The Bacillus in the intestine of group C has the highest relative abundance among all groups. Overall, it can generally be concluded that dietary supplementation of indigenous Bacillus subtilis and Bacillus licheniformis (group C) can improve the intestinal morphology, digestion, and absorption enzyme activities, enhance intestinal mucosal immunity and barrier function, and maintain the intestinal microbial balance of R. lagowskii.


Asunto(s)
Bacillus , Cipriniformes , Probióticos , Animales , Bacillus/fisiología , Alimentación Animal/análisis , Interleucina-10/farmacología , Probióticos/farmacología , Claudina-2 , Claudina-4 , Interleucina-8/farmacología , Intestinos , Bacillus subtilis/fisiología , Lipasa , Péptido Hidrolasas , Amilasas , Factor de Crecimiento Transformador beta/farmacología
6.
Fish Shellfish Immunol ; 127: 703-714, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35817364

RESUMEN

To study the effects of dietary methionine on growth performance, immunity, antioxidant capacity, protein metabolism, inflammatory response and apoptosis factors in Chinese mitten crabs (Eriocheir sinensis). Five diets with different methionine levels (0.63%, 0.85%, 1.06%, 1.25% and 1.47%) were fed to E. sinensis for 8 weeks. Results showed that in the 1.25% Met group, both growth performance and feed utilization were significantly increased. The crude protein content of crab muscle in the 1.06% and 1.25% Met groups was significantly higher than that in the control group. The immune and antioxidant enzyme activities, as well as gene expression levels of anti-lipopolysaccharide factor 1 (ALF1), Crustin-1, prophenoloxidase (proPO), cap 'n' collar isoform C (CncC) in 1.25% Met group were significantly higher than other groups. The activities of adenosine deaminase (ADA) and glutamate transaminase (GPT) in serum decreased first and then increased with the increase of methionine content, while the changes of ADA and GPT in hepatopancreas increased first and then decreased. 1.25% Met group exhibited significantly increased levels of GOT, GPT, and ADA compared to the control group. 1.25% Met diet group significantly up-regulated protein synthesis and anti-apoptotic factors, and significantly down-regulated inflammatory and pro-apoptotic factors in hepatopancreas. At 1.25% in the diet, methionine was found to boost E. sinensis growth, muscle protein deposition and immunity, as well as its antioxidant capacity. Combined with the above results, based on the expression of factors involved in the mammalian target of rapamycin (mTOR) signaling pathway and the mitogen-activated protein kinase (MAPK) signaling pathway, it is proved that methionine can not only promote protein metabolism, improve feed utilization, but also alleviate the inflammatory response and apoptosis caused by oxidative stress in the body.


Asunto(s)
Antioxidantes , Braquiuros , Alimentación Animal/análisis , Animales , Antioxidantes/metabolismo , Braquiuros/metabolismo , China , Dieta , Suplementos Dietéticos , Inmunidad Innata , Mamíferos/metabolismo , Metionina/farmacología , Transducción de Señal , Sirolimus/farmacología , Serina-Treonina Quinasas TOR/genética , Serina-Treonina Quinasas TOR/metabolismo
7.
Phys Chem Chem Phys ; 23(35): 19673-19679, 2021 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-34524289

RESUMEN

The quantum anomalous Hall (QAH) effect has been experimentally observed in magnetically-doped topological insulators. However, the QAH effect is only seen at extremely low temperatures due to the weak magnetic coupling, small band gap and low carrier mobility. Here, based on first-principles density functional theory, we predict that the Janus Mn2X3Y3 (X, Y) = F, Cl, Br, I are high Curie temperature ferromagnets. Furthermore, we find that they are Dirac half-metals characterized by a Dirac cone in one spin channel with carrier mobilities comparable to freestanding germanene and a large band gap in the other spin channel except for Mn2F3I3. Simultaneously, when the spin-orbital coupling interaction is considered, the Janus Mn2F3Cl3, Mn2Cl3Br3, and Mn2Br3I3 exhibit a nontrivial band gap, indicating that they host a QAH phase. More interestingly, both the Chern number sign and the chiral edge current are tuned by changing the direction of magnetization. Moreover, we find that topological properties are related to the lattice constant and magnetocrystalline anisotropy. Our findings would suggest the possibility of not only realizing the QAH effect but also designing the flow direction of the edge current.

8.
Fish Shellfish Immunol ; 93: 1100-1110, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31422179

RESUMEN

Nrf2/Keap1 pathway is associated with oxidative stress. l-carnitine is currently under preclinical evaluation as a antioxidant, but the use of l-carnitine in aquaculture has been poorly evaluated and so far no mechanism has been demonstrated. Here, we explored the effects of l-carnitine in vitro and in vivo and discussed the possible molecular mechanisms involved. Firstly, Nrf2-siRNA significantly knocked down the mRNA level of Nrf2 in FHM cells. Thus, the activities of antioxidant enzymes (T-SOD, CAT, GSH-PX) and the level of antioxidant substance (GSH) and the level of MDA showed that Nrf2-siRNA pretreatment weakened the protective effect of l-carnitine. Moreover, the mRNA levels of Keap1, Nrf2, Maf and HO-1 indicated that l-carnitine regulated Nrf2/Keap1 activation. Furthermore, oxidized fish oil remarkably suppressed growth in Rhynchocypris lagowski Dybowski, and the lower antioxidant capacity was also observed in liver. According to the results of immune related indexes (the levels of IL-1ß, TNF-α, LZM, AKP) in serum and the mRNA levels of immune related genes (NF-κB, IL-1ß, TNF-α, IL-8, IL-10 and TGF-ß) in liver, oxidized fish oil also induced inflammatory response in fish. Also, l-carnitine supplementation can relieve this bad condition. In conclusion, l-carnitine regulated Nrf2/Keap1 activation in vitro and in vivo and protected oxidized fish oil-induced inflammation response by inhibiting the NF-κB signaling pathway in Rhynchocypris lagowski Dybowski.


Asunto(s)
Carnitina/metabolismo , Cyprinidae/inmunología , Enfermedades de los Peces/inmunología , Proteínas de Peces/metabolismo , Sustancias Protectoras/metabolismo , Transducción de Señal/efectos de los fármacos , Animales , Antiinflamatorios/administración & dosificación , Antiinflamatorios/farmacología , Antioxidantes/administración & dosificación , Antioxidantes/farmacología , Carnitina/administración & dosificación , Proteínas Portadoras/metabolismo , Línea Celular , Cyprinidae/genética , Cyprinidae/crecimiento & desarrollo , Relación Dosis-Respuesta a Droga , Enfermedades de los Peces/tratamiento farmacológico , Aceites de Pescado/farmacología , Inflamación/tratamiento farmacológico , Inflamación/inmunología , Inflamación/veterinaria , Factor 2 Relacionado con NF-E2/metabolismo , FN-kappa B/metabolismo , Oxidación-Reducción , Estrés Oxidativo , Sustancias Protectoras/administración & dosificación , Distribución Aleatoria
9.
Phys Chem Chem Phys ; 21(18): 9310-9316, 2019 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-30993296

RESUMEN

Realizing topological Dirac states in two-dimensional (2D) magnetic materials is particularly important to spintronics. Here, we propose that such states can be obtained in a transition-metal (Hf) monolayer grown on a 2D substrate with hexagonal hollow geometry (graphyne). We find that the significant orbital hybridizations between Hf and C atoms can induce sizable magnetism and bring three Dirac cones at/around each high-symmetry K(K') point in the Brillouin zone. One Dirac cone is formed by pure spin-up electrons from the dz2 orbital of Hf, and the remaining two are formed by crossover between spin-up electrons from the dz2 orbital and spin-down electrons from the hybridization of the dxy/x2-y2 orbitals of Hf atoms and the pz orbital of C atoms. We also find that the spin-orbit coupling effect can open sizable band gaps for the Dirac cones. The Berry curvature calculations further show the nontrivial topological nature of the system with a negative Chern number C = -3, which is mainly attributed to the Dirac states. Molecular dynamics simulations confirm the system's thermodynamic stability approaching room temperature. The results provide a new avenue for realizing the high-temperature quantum anomalous Hall effect based on 2D transition-metals.

10.
RSC Adv ; 9(23): 13042-13047, 2019 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-35520755

RESUMEN

In this paper, one-step preparation of graphene/gold nanoparticle hydrogel film through the hydrothermal method is reported. The hydrogel film could be formed on a glass substrate under hydrothermal conditions, and upon freeze-drying, the aerogel film of 40 µm thickness with satisfying flexibility and strength is obtained. The aerogel composite film is characterized by scanning/transmission electron microscopy, X-ray diffraction, Raman spectroscopy and X-ray photoelectron spectroscopy. Moreover, the aerogel film is directly used as the electrochemical electrode for sensing H2O2, and exhibits good performance with a broad linear range, low detection limit and excellent selectivity. This work provides a route for the fabrication of graphene film material with wide potential in various aspects.

11.
Acta Crystallogr C Struct Chem ; 74(Pt 2): 171-176, 2018 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-29400332

RESUMEN

A dimerized 1,3-diazaazulene derivative, namely 1,4-bis(1,3-diazaazulen-2-yl)benzene [or 2,2'-(1,4-phenylene)bis(1,3-diazaazulene)], C22H14N4, (I), has been synthesized successfully through the condensation reaction between 2-methoxytropone and benzene-1,4-dicarboximidamide hydrochloride, and was characterized by 1H NMR and 13C NMR spectroscopies, and ESI-MS. X-ray diffraction analysis reveals that (I) has a nearly planar structure with good π-electron delocalization, indicating that it might serve as a π building block. The crystal belongs to the monoclinic system. One-dimensional chains were formed along the a axis through π-π interactions and adjacent chains are stabilized by C-H...N interactions, forming a three-dimensional architecture. The solid emission of (I) in the crystalline form exhibited a 170 nm red shift compared with that in the solution state. The observed optical bandgap for (I) is 3.22 eV and a cyclic voltammetry experiment confirmed the energy levels of the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO). The calculated bandgap for (I) is 3.37 eV, which is very close to the experimental result. In addition, the polarizability and hyperpolarizability of (I) were appraised for its further application in second-order nonlinear optical materials.

12.
ChemSusChem ; 10(24): 4872-4878, 2017 12 22.
Artículo en Inglés | MEDLINE | ID: mdl-29094491

RESUMEN

The photovoltaic performance of organic-inorganic hybrid perovskite solar cells has reached a bottleneck after rapid development in last few years. Further breakthrough in this field requires deeper understanding of the underlying mechanism of the photoelectric conversion process in the device, especially the dynamics of charge-carrier recombination. Originating from dye-sensitized solar cells (DSSCs), mesoporous-structured perovskite solar cells (MPSCs) have shown many similarities to DSSCs with respect to their photoelectric dynamics. Herein, by applying the multiple-trapping model of the charge-recombination dynamic process for DSSCs in MPSCs, with rational modification, a novel physical model is proposed to describe the dynamics of charge recombination in MPSCs that exhibits good agreement with experimental data. Accordingly, the perovskite- and TiO2 -dominating charge-recombination processes are assigned and their relationships with the trap-state distribution are also discussed. An optimal balance between these two dynamic processes is required to improve the performance of mesoporous-structured perovskite devices.

13.
Nano Lett ; 17(10): 6195-6202, 2017 10 11.
Artículo en Inglés | MEDLINE | ID: mdl-28960082

RESUMEN

The discovery of intriguing properties related to the Dirac states in graphene has spurred huge interest in exploring its two-dimensional group-IV counterparts, such as silicene, germanene, and stanene. However, these materials have to be obtained via synthesizing on substrates with strong interfacial interactions, which usually destroy their intrinsic π(pz)-orbital Dirac states. Here we report a theoretical study on the existence of Dirac states arising from the px,y orbitals instead of pz orbitals in silicene on 4H-SiC(0001), which survive in spite of the strong interfacial interactions. We also show that the exchange field together with the spin-orbital coupling give rise to a detectable band gap of 1.3 meV. Berry curvature calculations demonstrate the nontrivial topological nature of such Dirac states with a Chern number C = 2, presenting the potential of realizing quantum anomalous Hall effect for silicene on SiC(0001). Finally, we construct a minimal effective model to capture the low-energy physics of this system. This finding is expected to be also applicable to germanene and stanene and imply great application potentials in nanoelectronics.

14.
Chemistry ; 23(16): 3986-3992, 2017 Mar 17.
Artículo en Inglés | MEDLINE | ID: mdl-28120437

RESUMEN

Organic-inorganic halide perovskite solar cells have rapidly come to prominence in the photovoltaic field. In this context, CH3 NH3 PbI3 , as the most widely adopted active layer, has been attracting great attention. Generally, in a CH3 NH3 PbI3 layer, unreacted PbI2 inevitably coexists with the perovskite crystals, especially following a two-step fabrication process. There appears to be a consensus that an appropriate amount of unreacted PbI2 is beneficial to the overall photovoltaic performance of a device, the only disadvantageous aspect of excess residual PbI2 being viewed as its insulating nature. However, the further development of such perovskite-based devices requires a deeper understanding of the role of residual PbI2 . In this work, PbI2 -enriched and PbI2 -controlled perovskite films, as two extreme cases, have been prepared by modulating the crystallinity of a pre-deposited PbI2 film. The effects of excess residual PbI2 have been elucidated on the basis of spectroscopic and optoelectronic studies. The initial charge separation, the trap-state density, and the trap-state distribution have all been found to be adversely affected in PbI2 -enriched devices, to the detriment of photovoltaic performance. This leads to a biphasic recombination process and accelerates the charge carrier recombination dynamics.

15.
Nanoscale ; 8(41): 17815-17819, 2016 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-27714113

RESUMEN

Using non-equilibrium molecular dynamics simulations, we have studied the effect of disorder on the thermal conductivity of two-dimensional (2D) C1-xNx alloys. We find that the thermal conductivity not only depends on the substitution concentration of nitrogen, but also strongly depends on the disorder distribution. A general linear relationship is revealed between the thermal conductivity and the participation ratio of phonons in 2D alloys. Localization mode analysis further indicates that the thermal conductivity variation in the ordered alloys can be attributed to the number of inequivalent atoms. As for the disordered alloys, we find that the thermal conductivity variation can be described by a simple linear formula with the disorder degree and the substitution concentration. The present study suggests some general guidance for phonon manipulation and thermal engineering in low dimensional alloys.

16.
Phys Chem Chem Phys ; 18(17): 12128-34, 2016 04 28.
Artículo en Inglés | MEDLINE | ID: mdl-27076212

RESUMEN

Organic-inorganic halide perovskite solar cells are becoming the next big thing in the photovoltaic field owing to their rapidly developing photoelectric conversion performance. Herein, mesoporous structured perovskite devices with various perovskite grain sizes are fabricated by a sequential dropping method, and the charge recombination dynamics is investigated by transient optical-electric measurements. All devices exhibit an overall power conversion efficiency around 15%. More importantly, a biphasic trap-limited charge recombination process is proposed and interpreted by taking into account the specific charge accumulation mechanism in perovskite solar cells. At low Fermi levels, photo-generated electrons predominately populate in the perovskite phase, while at high Fermi levels, most electrons occupy traps in mesoporous TiO2. As a result, the dynamics of charge recombination is, respectively, dominated by the perovskite phase and mesoporous TiO2 in these two cases. The present work would give a new perspective on the charge recombination process in meso-structured perovskite solar cells.

17.
J Phys Condens Matter ; 28(14): 145003, 2016 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-26965319

RESUMEN

We have performed nonequilibrium molecular dynamics calculations on the length (L) dependence of thermal conductivity (Κ) of silicene both supported on and sandwiched between the smooth surfaces, i.e. h-BN, at room temperature. We find that Κ of silicene follows a power law Κ [proportional] L(ß), with ß increasing from about 0.3-0.4 under the effect of interface coupling, showing an enhancement of the ballistic thermal transport of silicene. We also find that ß can be further increased to about 0.6 by increasing the interface coupling strength for the silicene sandwiched between h-BN. The increase of ß for the supported case is found to come from the variation of the flexural acoustic (ZA) phonon mode and the first optical phonon mode induced by the substrate, whereas the unusual increase of ß for the sandwiched case is attributed to the increment of velocities of all three acoustic phonon modes. These findings provide an interesting route for manipulating the ballistic energy flow in nanomaterials.

18.
Fitoterapia ; 98: 248-53, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25172105

RESUMEN

Two new trimeric caffeic acids, named salvianolic acids T and U (1 and 2), were isolated from the underground part of Salvia miltiorrhiza. Their structures, consisting of three caffeic acid units, were determined based on extensive 1D- and 2D-spectroscopic analyses and electronic circular dichroism (ECD) calculations.


Asunto(s)
Alquenos/química , Ácidos Cafeicos/química , Polifenoles/química , Salvia miltiorrhiza/química , Alquenos/aislamiento & purificación , Ácidos Cafeicos/aislamiento & purificación , Estructura Molecular , Raíces de Plantas/química , Polifenoles/aislamiento & purificación
19.
J Clin Pharmacol ; 54(2): 234-9, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24142885

RESUMEN

This open-label, multi-dose, single-center, sequential, inpatient study evaluated the effects of a two herb combination drug (T89, Danshen plus Sanqi) on the steady-state pharmacodynamics (PD) and pharmacokinetics (PK) of warfarin in 24 healthy volunteers. Twenty-three subjects attained a stable international normalized ratio (INR) by taking warfarin alone prior to 1-week of added-on use of T89. INR was not increased after the addition of T89 for 7 days (P > .05). The 90% confidence interval (CI) of the geometric mean ratio for maximum plasma concentrations (Cmax) and area under curve (AUClast ) of both R- and S-warfarin when warfarin was administered with or without T89 was within the 0.80 to 1.25 equivalence ratio. These results indicate that T89 has no effect on the steady-state PD and PK of warfarin. Warfarin and T89 dose adjustments are not required when these two drugs are co-administrated in clinical practice.


Asunto(s)
Anticoagulantes/farmacocinética , Medicamentos Herbarios Chinos/farmacología , Interacciones de Hierba-Droga , Warfarina/farmacocinética , Adolescente , Adulto , Anticoagulantes/sangre , Medicamentos Herbarios Chinos/administración & dosificación , Medicamentos Herbarios Chinos/efectos adversos , Femenino , Voluntarios Sanos , Humanos , Relación Normalizada Internacional , Masculino , Persona de Mediana Edad , Panax notoginseng , Tiempo de Protrombina , Salvia miltiorrhiza , Warfarina/sangre , Adulto Joven
20.
J Cardiovasc Pharmacol ; 60(6): 513-9, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23232790

RESUMEN

T89 (Dantonic) is a modern herbal medicine currently used in Chinese hospitals for the management of ischemic heart disease. This dose-escalation clinical trial aims to assess tolerability of Western people to T89. Healthy Australian adults of non-Asian background orally took a single dosage of 6, 8, 10, 12, 13, 14, 15, or 16 T89 capsules (6 people for each dose) and were assessed with respect to symptoms and physical signs, electrocardiogram, hematology, plasma biochemistry, and urinalysis. Secondary objectives were to determine the dose-limiting toxicity and maximum-tolerated dose. It found that a single dose of T89 up to 16 capsules was not associated with significant adverse events or abnormalities in clinical laboratory tests and electrocardiogram parameters, except minor symptoms reported included mild and transient dizziness, stomach discomfort, diarrhea, and involuntary muscular contraction. The incident rate of these symptoms was generally low (1/30, 3.3%) but increased (7/18, 38.9%) in higher dose (≥14 capsules) groups. No defined dose-limiting toxicity events occurred; so the study could not define the maximum-tolerated dose. In conclusion, a single dose of T89 up to 13 capsules, 4 times of a regular therapeutic dosage, is generally safe and tolerated by individuals of non-Asian background.


Asunto(s)
Fármacos Cardiovasculares/administración & dosificación , Medicamentos Herbarios Chinos/administración & dosificación , Administración Oral , Adolescente , Adulto , Análisis de Varianza , Australia , Cápsulas , Fármacos Cardiovasculares/efectos adversos , Relación Dosis-Respuesta a Droga , Medicamentos Herbarios Chinos/efectos adversos , Femenino , Humanos , Masculino , Dosis Máxima Tolerada , Persona de Mediana Edad , Panax notoginseng , Salvia miltiorrhiza , Factores de Tiempo , Adulto Joven
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