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1.
Angew Chem Int Ed Engl ; : e202406082, 2024 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-38807303

RESUMEN

Commercial alkaline water electrolysers typically operate at 80 °C to minimize energy consumption. However, NiFe-based catalysts, considered as one of the most promising candidates for anode, encounter the bottleneck of high solubility at such temperatures. Herein, we discover that the dissolution of NiFe layered double hydroxides (NiFe-LDH) during operation not only leads to degradation of anode itself, but also deactivates cathode for water splitting, resulting in decay of overall electrocatalytic performance. Aiming to suppress the dissolution, we employed oxyanions as inhibitors in electrolyte. The added phosphates to the electrolyte inhibit the loss of NiFe-LDH active sites at 400 mA cm-2 to 1/3 of the original amount, thus reducing the rate of performance decay by 25-fold. Furthermore, the usage of borates, sulfates, and carbonates yields similar results, demonstrating the reliability and universality of the active site dissolution inhibitor, and its role in elevated water electrolysis.

2.
J Med Internet Res ; 25: e49137, 2023 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-37910154

RESUMEN

BACKGROUND: Gay geosocial networking apps, also known as "gay apps," have gained increasing popularity in the men who have sex with men (MSM) community. Certain sexuality traits and gay app use are both associated with high-risk sexual behaviors among MSM. However, little is known about the underlying mechanism of such relationships. OBJECTIVE: Based on the uses and gratifications theory, this study aimed to test the mediation effect of gay app use on the relationship between sexuality traits (sexual compulsivity and sexual sensation seeking) and high-risk sexual behaviors (multiple sexual partners and unprotected anal intercourse) among MSM. METHODS: A cross-sectional, multicenter study was conducted in Wuhan and Changsha, China, from August to October 2020. A representative sample of 402 MSM was recruited through respondent-driven sampling. A self-administered web-based structured questionnaire was used to collect data on sociodemographic information, high-risk sexual behaviors, gay app use, sexual compulsivity, and sexual sensation seeking. Path analysis was conducted to assess the mediation effect. RESULTS: Our study revealed that 67.42% (n=271) of MSM used gay apps for seeking potential sexual partners, with 37.06% (n=149) of them engaging in unprotected anal intercourse, and 45.42% (n=218) of them having multiple sexual partners. Of the participants, 17.16% (n=69) reported significant sexual compulsivity, while 29.10% (n=117) reported significant sexual sensation seeking. Notably, gay app usage partially mediated the relationship between sexual compulsivity and multiple sexual partners but fully mediated the relationship between sexual compulsivity and unprotected anal intercourse. Furthermore, gay app usage partially mediated the relationship between sexual sensation seeking and multiple sexual partners but fully mediated the relationship between sexual sensation seeking and unprotected anal intercourse. CONCLUSIONS: High-risk sexual behaviors are common among MSM. Most MSM rely on gay apps to find sexual partners, which, when combined with higher levels of sexual compulsivity and sexual sensation seeking, can increase the likelihood of engaging in high-risk sexual behaviors. Therefore, interventions aimed at reducing these behaviors among MSM should focus on addressing the use of gay apps, while also considering the influence of their sexuality traits on gay app use.


Asunto(s)
Aplicaciones Móviles , Minorías Sexuales y de Género , Masculino , Humanos , Homosexualidad Masculina , Análisis de Mediación , Estudios Transversales , Sexualidad , China
3.
Angew Chem Int Ed Engl ; 62(40): e202309882, 2023 Oct 02.
Artículo en Inglés | MEDLINE | ID: mdl-37603411

RESUMEN

The direct seawater electrolysis at high current density and low overpotential affords an effective strategy toward clean and renewable hydrogen fuel production. However, the severe corrosion of anode as a result of the saturation of Cl- upon continuous seawater feeding seriously hamper the electrolytic process. Herein, cobalt ferricyanide / cobalt phosphide (CoFePBA/Co2 P) anodes with Cap/Pin structure are synthesized, which stably catalyze alkaline saturated saline water oxidation at 200-2000 mA cm-2 over hundreds of hours without corrosion. Together with the experimental findings, the molecular dynamics simulations reveal that PO4 3- and Fe(CN)6 3- generated by the electrode play synergistic role in repelling Cl- via electrostatic repulsion and dense coverage, which reduced Cl- adsorption by nearly 5-fold. The novel anionic synergy endow superior corrosion protection for the electrode, and is expected to promote the practical application of saline water electrolysis.

4.
Angew Chem Int Ed Engl ; 62(3): e202213711, 2023 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-36418219

RESUMEN

Electrochemical reduction of nitrite (NO2 - ) offers an energy-efficient route for ammonia (NH3 ) synthesis and reduction of the level of nitrite, which is one of the major pollutants in water. However, the near 100 % Faradaic efficiency (FE) has yet to be achieved due to the complicated reduction route with several intermediates. Here, we report that carbon dioxide (CO2 ) can enhance the nitrite electroreduction to ammonia on copper nanowire (Cu NW) catalysts. In a broad potential range (-0.7∼-1.3 V vs. RHE), the FE of nitrite to ammonia is close to 100 % with a 3.5-fold increase in activity compared to that obtained without CO2. In situ Raman spectroscopy and density functional theory (DFT) calculations indicate that CO2 acts as a catalyst to facilitate the *NO to *N step, which is the rate determining step for ammonia synthesis. The promotion effect of CO2 can be expanded to electroreduction of other nitro-compounds, such as nitrate to ammonia and nitrobenzene to aniline.

5.
Small ; 18(30): e2202513, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35780475

RESUMEN

Developing highly active, durable, and cost-effective electrocatalysts for the oxygen evolution reaction (OER) is of prime importance in proton exchange membrane (PEM) water electrolysis techniques. Ru-based catalysts have high activities but always suffer from severe fading and dissolution issues, which cannot satisfy the stability demand of PEM. Herein, a series of iridium-doped yttrium ruthenates pyrochlore catalysts is developed, which exhibit better activity and much higher durability than commercial RuO2 , IrO2 , and most of the reported Ru or Ir-based OER electrocatalysts. Typically, the representative Y2 Ru1.2 Ir0.8 O7 OER catalyst demands a low overpotential of 220 mV to achieve 10 mA cm-2 , which is much lower than that of RuO2 (300 mV) and IrO2 (350 mV). In addition, the catalyst does not show obvious performance decay or structural degradation over a 2000 h stability test. EXAFS and XPS co-prove the reduced valence state of ruthenium and iridium in pyrochlore contributes to the improved activity and stability. Density functional theory reveals that the potential-determining steps barrier of OOH* formation is greatly depressed through the synergy effect of Ir and Ru sites by balancing the d band center and oxygen intermediates binding ability.

6.
Invest New Drugs ; 40(3): 606-613, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35190972

RESUMEN

PURPOSE: This study aimed to compare the safety, tolerability, pharmacokinetics (PK), and bioequivalence of a test humanized recombinant monoclonal antibody targeting human epidermal growth factor receptor-2 (HER-2) with the reference Herceptin®. MATERIALS AND METHODS: The trial consisted of two parts (part I and part II). Part I was an open-label, sequential-cohort dose-escalation study, where 16 healthy subjects were either intravenously infused with QLHER2 (test) at single doses escalating from 0.2 to 6 mg/kg (0.2, 1, 2, 4, and 6 mg/kg) or given 4 mg/kg Herceptin (reference) for evaluating the safety, tolerability, and PK of QLHER2. Part II was a randomized, double-blind, parallel-group study to evaluate the bioequivalence of QLHER2 and Herceptin in 60 subjects. RESULTS: Following a 1.5-h intravenous infusion of single ascending doses of QLHER2 (1, 2, 4, or 6 mg/kg) in part I, Cmax and Tmax were 19.43-120.01 µg/mL and 68.91-157.87 h, respectively. AUC0-t and CL were 1.91-34.21 h·µg/mL and 0.54-0.12 mL/h/kg, indicating lower clearance at higher doses, with a greater than proportional increase in AUC0-t and t1/2 of 68.91-157.87 h. In part II, serum concentrations were comparable between QLHER2 and Herceptin over a 70-day sampling period, and the QLHER2/Herceptin ratios of Cmax and AUC0-t were 105.90% [90% confidence interval (CI): 95.69%-117.26%] and 95.79% (90% CI: 87.74%-106.40%), respectively. CONCLUSION: The 90% CI value of Cmax and AUC0-t for QLHER2/Herceptin ratio ranged between 80.0%-125.00%, indicating that QLHER2 was bioequivalent to Herceptin. These results support further evaluation of QLHER2. Trial registration number: ChiCTR2000041577 and ChiCTR2100041802. Date of registration: 30th December, 2020 and 5th January 2021.


Asunto(s)
Anticuerpos Monoclonales Humanizados , Área Bajo la Curva , China , Estudios Cruzados , Voluntarios Sanos , Humanos , Equivalencia Terapéutica , Trastuzumab/efectos adversos
7.
Proc Natl Acad Sci U S A ; 116(14): 6624-6629, 2019 04 02.
Artículo en Inglés | MEDLINE | ID: mdl-30886092

RESUMEN

Electrolysis of water to generate hydrogen fuel is an attractive renewable energy storage technology. However, grid-scale freshwater electrolysis would put a heavy strain on vital water resources. Developing cheap electrocatalysts and electrodes that can sustain seawater splitting without chloride corrosion could address the water scarcity issue. Here we present a multilayer anode consisting of a nickel-iron hydroxide (NiFe) electrocatalyst layer uniformly coated on a nickel sulfide (NiSx) layer formed on porous Ni foam (NiFe/NiSx-Ni), affording superior catalytic activity and corrosion resistance in solar-driven alkaline seawater electrolysis operating at industrially required current densities (0.4 to 1 A/cm2) over 1,000 h. A continuous, highly oxygen evolution reaction-active NiFe electrocatalyst layer drawing anodic currents toward water oxidation and an in situ-generated polyatomic sulfate and carbonate-rich passivating layers formed in the anode are responsible for chloride repelling and superior corrosion resistance of the salty-water-splitting anode.

8.
Proc Natl Acad Sci U S A ; 116(48): 23915-23922, 2019 Nov 26.
Artículo en Inglés | MEDLINE | ID: mdl-31723041

RESUMEN

Electrochemical reduction of CO2 to useful chemicals has been actively pursued for closing the carbon cycle and preventing further deterioration of the environment/climate. Since CO2 reduction reaction (CO2RR) at a cathode is always paired with the oxygen evolution reaction (OER) at an anode, the overall efficiency of electrical energy to chemical fuel conversion must consider the large energy barrier and sluggish kinetics of OER, especially in widely used electrolytes, such as the pH-neutral CO2-saturated 0.5 M KHCO3 OER in such electrolytes mostly relies on noble metal (Ir- and Ru-based) electrocatalysts in the anode. Here, we discover that by anodizing a metallic Ni-Fe composite foam under a harsh condition (in a low-concentration 0.1 M KHCO3 solution at 85 °C under a high-current ∼250 mA/cm2), OER on the NiFe foam is accompanied by anodic etching, and the surface layer evolves into a nickel-iron hydroxide carbonate (NiFe-HC) material composed of porous, poorly crystalline flakes of flower-like NiFe layer-double hydroxide (LDH) intercalated with carbonate anions. The resulting NiFe-HC electrode in CO2-saturated 0.5 M KHCO3 exhibited OER activity superior to IrO2, with an overpotential of 450 and 590 mV to reach 10 and 250 mA/cm2, respectively, and high stability for >120 h without decay. We paired NiFe-HC with a CO2RR catalyst of cobalt phthalocyanine/carbon nanotube (CoPc/CNT) in a CO2 electrolyzer, achieving selective cathodic conversion of CO2 to CO with >97% Faradaic efficiency and simultaneous anodic water oxidation to O2 The device showed a low cell voltage of 2.13 V and high electricity-to-chemical fuel efficiency of 59% at a current density of 10 mA/cm2.

9.
Chem Soc Rev ; 50(15): 8790-8817, 2021 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-34160484

RESUMEN

The electrocatalytic oxygen evolution reaction (OER) is a critical half-cell reaction for hydrogen production via water electrolysis. However, the practical OER suffers from sluggish kinetics and thus requires efficient electrocatalysts. Transition metal-based layered double hydroxides (LDHs) represent one of the most active classes of OER catalysts. An in-depth understanding of the activity of LDH based electrocatalysts can promote further rational design and active site regulation of high-performance electrocatalysts. In this review, the fundamental understanding of the structural characteristics of LDHs is demonstrated first, then comparisons and in-depth discussions of recent advances in LDHs as highly active OER catalysts in alkaline media are offered, which include both experimental and computational methods. On top of the active site identification and structural characterization of LDHs on an atomic scale, strategies to promote the OER activity are summarised, including doping, intercalation and defect-making. Furthermore, the concept of superaerophobicity, which has a profound impact on the performance of gas evolution electrodes, is explored to enhance LDHs and their derivatives for a large scale OER. In addition, certain operating standards for OER measurements are proposed to avoid inconsistency in evaluating the OER activity of LDHs. Finally, several key challenges in using LDHs as anode materials for large scale water splitting, such as the issue of stability and the adoption of membrane-electrode-assembly based electrolysers, are emphasized to shed light on future research directions.

10.
J Am Chem Soc ; 143(8): 3245-3255, 2021 03 03.
Artículo en Inglés | MEDLINE | ID: mdl-33617245

RESUMEN

Reducing CO2 to value-added multicarbon (C2+) fuels and chemicals using renewable energy is a viable way to circumvent CO2 buildup in the atmosphere and facilitate closing the carbon cycle. To date it remains a challenge to achieve high product selectivity and long-term stability of electrocatalytic carbon dioxide reduction reaction (CO2RR) especially at practically relevant high current levels >100 mA cm-2. Here, we report a simple electrodeposited Cu electrocatalyst on a hydrophobic porous gas-diffusion layer (GDL) electrode affording stable and selective CO2RR to C2+ products in near-neutral KCl electrolytes. By directing the CO2 stream to fully submerged hydrophobic GDLs in a H-cell, high C2+ partial current densities near 100 mA cm-2 were achieved. In a flow-cell setup, the Cu/GDL cathode in 2 M KCl afforded stable CO2RR superior to that in widely used KOH electrolytes. We found that Cu etching/corrosion associated with trace oxygen played a role in the catalyst instability in alkaline media under cathodic CO2RR conditions, a problem largely suppressed in near-neutral electrolyte. A two-electrode CO2 electrolyzer was constructed with a Cu/GDL cathode in KCl catholyte and an anode comprised of nickel-iron hydroxide on nickel foam (NiFe/NF) in a KOH anolyte separated by Nafion membrane. By periodically adding HCl to the KCl catholyte to compensate the increasing pH and remove accumulated (bi)carbonates, we observed little decay over ∼30 h in flow-cell CO2RR activity and selectivity at 150 mA cm-2 with a high Faradaic efficiency (FE) of ∼75% and energy efficiency of 40% for C2+ products.

11.
BMC Plant Biol ; 21(1): 306, 2021 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-34193042

RESUMEN

BACKGROUND: Outbreaks of insect pests in paddy fields cause heavy losses in global rice yield annually, a threat projected to be aggravated by ongoing climate warming. Although significant progress has been made in the screening and cloning of insect resistance genes in rice germplasm and their introgression into modern cultivars, improved rice resistance is only effective against either chewing or phloem-feeding insects. RESULTS: In this study, the results from standard and modified seedbox screening, settlement preference and honeydew excretion tests consistently showed that Qingliu, a previously known leaffolder-resistant rice variety, is also moderately resistant to brown planthopper (BPH). High-throughput RNA sequencing showed a higher number of differentially expressed genes (DEGs) at the infestation site, with 2720 DEGs in leaves vs 181 DEGs in sheaths for leaffolder herbivory and 450 DEGs in sheaths vs 212 DEGs in leaves for BPH infestation. The leaf-specific transcriptome revealed that Qingliu responds to leaffolder feeding by activating jasmonic acid biosynthesis genes and genes regulating the shikimate and phenylpropanoid pathways that are essential for the biosynthesis of salicylic acid, melatonin, flavonoids and lignin defensive compounds. The sheath-specific transcriptome revealed that Qingliu responds to BPH infestation by inducing salicylic acid-responsive genes and those controlling cellular signaling cascades. Taken together these genes could play a role in triggering defense mechanisms such as cell wall modifications and cuticular wax formation. CONCLUSIONS: This study highlighted the key defensive responses of a rarely observed rice variety Qingliu that has resistance to attacks by two different feeding guilds of herbivores. The leaffolders are leaf-feeder while the BPHs are phloem feeders, consequently Qingliu is considered to have dual resistance. Although the defense responses of Qingliu to both insect pest types appear largely dissimilar, the phenylpropanoid pathway (or more specifically phenylalanine ammonia-lyase genes) could be a convergent upstream pathway. However, this possibility requires further studies. This information is valuable for breeding programs aiming to generate broad spectrum insect resistance in rice cultivars.


Asunto(s)
Herbivoria/fisiología , Oryza/genética , Oryza/parasitología , Floema/parasitología , Hojas de la Planta/parasitología , Transcriptoma/genética , Animales , Pared Celular/metabolismo , Ciclopentanos/metabolismo , Perfilación de la Expresión Génica , Regulación de la Expresión Génica de las Plantas , Ontología de Genes , Hemípteros/fisiología , Metabolismo de los Lípidos , Oxilipinas/metabolismo , Reguladores del Crecimiento de las Plantas/farmacología , Ácido Salicílico/metabolismo , Ácido Shikímico/metabolismo , Transcripción Genética
12.
Small ; 17(45): e2102078, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34612000

RESUMEN

Electrocatalytic water splitting in acidic media is a promising strategy for grid scale production of hydrogen using renewable energy, but challenges still exist in the development of advanced catalysts with both high activity and stability. Herein, it is reported that iridium doped tungsten trioxide (Ir-doped WO3 ) with arrayed structure and confined Ir sites is an efficient and durable bi-functional catalyst for overall acidic water splitting. A low overpotential (258 mV) is required to achieve an oxygen evolution reaction current density of 10 mA cm-2 in 0.5 m H2 SO4 solution. Meanwhile, Ir-doped WO3 processes a similar intrinsic activity to Pt/C toward hydrogen evolution reaction. Overall water splitting using the bi-functional Ir-doped WO3 catalyst shows low cell voltages of 1.56 and 1.68 V to drive the current densities of 10 and 100 mA cm-2 , respectively, with only 16 mV decay observed after 60 h continuous electrolysis under the current density of 100 mA cm-2 . Structural analysis and density functional theory calculation indicate that the adjusted coordination environment of Ir within the crystalline matrix of WO3 contributes to the high activity and durability.

13.
Proc Natl Acad Sci U S A ; 115(26): 6590-6595, 2018 06 26.
Artículo en Inglés | MEDLINE | ID: mdl-29891702

RESUMEN

With suppressed photon scattering and diminished autofluorescence, in vivo fluorescence imaging in the 1,500- to 1,700-nm range of the near-IR (NIR) spectrum (NIR-IIb window) can afford high clarity and deep tissue penetration. However, there has been a lack of NIR-IIb fluorescent probes with sufficient brightness and aqueous stability. Here, we present a bright fluorescent probe emitting at ∼1,600 nm based on core/shell lead sulfide/cadmium sulfide (CdS) quantum dots (CSQDs) synthesized in organic phase. The CdS shell plays a critical role of protecting the lead sulfide (PbS) core from oxidation and retaining its bright fluorescence through the process of amphiphilic polymer coating and transferring to water needed for imparting aqueous stability and compatibility. The resulting CSQDs with a branched PEG outer layer exhibited a long blood circulation half-life of 7 hours and enabled through-skin, real-time imaging of blood flows in mouse vasculatures at an unprecedented 60 frames per second (fps) speed by detecting ∼1,600-nm fluorescence under 808-nm excitation. It also allowed through-skin in vivo confocal 3D imaging of tumor vasculatures in mice with an imaging depth of ∼1.2 mm. The PEG-CSQDs accumulated in tumor effectively through the enhanced permeation and retention effect, affording a high tumor-to-normal tissue ratio up to ∼32 owing to the bright ∼1,600-nm emission and nearly zero autofluorescence background resulting from a large ∼800-nm Stoke's shift. The aqueous-compatible CSQDs are excreted through the biliary pathway without causing obvious toxicity effects, suggesting a useful class of ∼1,600-nm emitting probes for biomedical research.


Asunto(s)
Colorantes Fluorescentes , Imagenología Tridimensional/métodos , Microscopía Intravital/métodos , Microscopía Fluorescente/métodos , Imagen Óptica/métodos , Puntos Cuánticos , Adenocarcinoma/irrigación sanguínea , Adenocarcinoma/secundario , Animales , Neoplasias del Colon/patología , Estabilidad de Medicamentos , Arteria Femoral/ultraestructura , Vena Femoral/ultraestructura , Colorantes Fluorescentes/análisis , Colorantes Fluorescentes/farmacocinética , Colorantes Fluorescentes/toxicidad , Semivida , Miembro Posterior/irrigación sanguínea , Microscopía Intravital/instrumentación , Plomo/química , Ratones , Ratones Endogámicos C57BL , Microscopía Confocal/instrumentación , Microscopía Confocal/métodos , Microscopía Electrónica , Microscopía Fluorescente/instrumentación , Imagen Óptica/instrumentación , Puntos Cuánticos/análisis , Puntos Cuánticos/química , Puntos Cuánticos/toxicidad , Sulfuros/química , Grabación en Video
14.
Molecules ; 26(7)2021 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-33915860

RESUMEN

Polymorphism exhibits different physicochemical properties, which can impact the bioavailability and bioactivity of solid drugs. This study focused on identifying the polymorphs of ginsenoside compound K (CK) and studying their different behaviors in pharmacokinetics (PK) and pharmacodynamics (PD). Four CK polymorphs (form I, II, III, and IV) from organic solvents were characterized by scanning electron microscope (SEM), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), Fourier transform infrared spectroscopy (FTIR), and powder X-ray diffraction (PXRD). A feasible LC-MS/MS method was exploited to determine the PK parameters. Form II displayed the most exposure, followed by form I, III, and IV. Notably, all forms showed sex dimorphism, and the bioavailability in the female group was about two-fold higher than in the male group. The PD properties were investigated in carrageenan-induced acute paw inflammation, and form II at 20 mg/kg showed significant inhibition of edema by 42.7%. This study clarified the polymorphic, PK, and PD characters of four crystal forms of CK, and the data suggested that form II had the best efficacy for drug development.


Asunto(s)
Antiinflamatorios/química , Antiinflamatorios/farmacocinética , Ginsenósidos/química , Ginsenósidos/farmacocinética , Animales , Área Bajo la Curva , Fenómenos Químicos , Estructura Molecular , Ratas , Análisis Espectral , Relación Estructura-Actividad
15.
J Am Chem Soc ; 142(16): 7276-7282, 2020 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-32250611

RESUMEN

Electrocatalytic CO2 reduction (CO2RR) to valuable fuels is a promising approach to mitigate energy and environmental problems, but controlling the reaction pathways and products remains challenging. Here a novel Cu2O nanoparticle film was synthesized by square-wave (SW) electrochemical redox cycling of high-purity Cu foils. The cathode afforded up to 98% Faradaic efficiency for electroreduction of CO2 to nearly pure formate under ≥45 atm CO2 in bicarbonate catholytes. When this cathode was paired with a newly developed NiFe hydroxide carbonate anode in KOH/borate anolyte, the resulting two-electrode high-pressure electrolysis cell achieved high energy conversion efficiencies of up to 55.8% stably for long-term formate production. While the high-pressure conditions drastically increased the solubility of CO2 to enhance CO2 reduction and suppress hydrogen evolution, the (111)-oriented Cu2O film was found to be important to afford nearly 100% CO2 reduction to formate. The results have implications for CO2 reduction to a single liquid product with high energy conversion efficiency.

16.
Invest New Drugs ; 38(6): 1826-1835, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-32535812

RESUMEN

We assessed the pharmacokinetics and safety of a single oral administration of selatinib to healthy Chinese subjects and evaluated the potential bioavailability advantage of selatinib relative to lapatinib. Healthy subjects aged 18-40 years were enrolled in this two-part study: Part 1, a single ascending dose (50-500 mg), randomized, double-blind, placebo-control study with 64 subjects; and Part 2, an open-label, positive control, randomized, three-treatment, three-period, three-sequence crossover design study, with 6 subjects administered a single 500-mg dose of selatinib tablets (A), selatinib suspension (B), or lapatinib tablets C) per cycle. In part 1, selatinib was well-tolerated up to the planned maximum dose of 500 mg; thus the maximum tolerated dose was not attained. Twenty-two adverse events were observed in 19 (36.5%) of the 52 subjects administered the test drug. The most common drug-related adverse event was diarrhea. The mean selatinib peak plasma concentration was 69.4-494 ng/mL, which was achieved in a median peak time of 3.5-4.5 h, with a mean elimination half-life between 13.8 and 15.8 h. In Part 2, A and B showed similar bioavailability. Plasma exposure to the active drug (selatinib plus the metabolite, lapatinib) after A intake was more than two-fold higher than that of the same dose of C. In the dose range of 50-500 mg, selatinib was safe and well-tolerated by healthy Chinese subjects, and it conformed with linear pharmacokinetics. Active exposure to selatinib was much greater than that to lapatinib, supporting its development as an adjuvant for anticancer treatment.


Asunto(s)
Compuestos de Anilina/administración & dosificación , Antineoplásicos/administración & dosificación , Quinazolinas/administración & dosificación , Receptor ErbB-2/antagonistas & inhibidores , Adolescente , Adulto , Compuestos de Anilina/efectos adversos , Compuestos de Anilina/sangre , Compuestos de Anilina/farmacocinética , Antineoplásicos/efectos adversos , Antineoplásicos/sangre , Antineoplásicos/farmacocinética , Disponibilidad Biológica , Estudios Cruzados , Método Doble Ciego , Receptores ErbB/antagonistas & inhibidores , Femenino , Voluntarios Sanos , Humanos , Lapatinib/metabolismo , Masculino , Quinazolinas/efectos adversos , Quinazolinas/sangre , Quinazolinas/farmacocinética , Equivalencia Terapéutica , Adulto Joven
17.
Langmuir ; 36(39): 11422-11428, 2020 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-32862650

RESUMEN

Understanding of dynamic behaviors of gas bubbles on solid surfaces has significant impacts on gas-involving electrochemical reactions, mineral flotation, and so on in industry. Contact angle (θ) is widely employed to characterize the wetting behaviors of bubbles on solid surfaces; however, it usually fluctuates within the bubble's advancing (θa) and receding (θr) range. Although the term of most-stable contact angle (θms) was defined previously as the closest valuable approximation for thermodynamically meaningful contact angle for a droplet on a solid surface, it has not been widely studied; and the precise θms measurement methods are inadequate to describe bubbles' wetting behaviors on solid surfaces. Herein, we proposed to take θms as the mean value of θa and θr, as a more accurate descriptor of gas bubbles' dynamic behaviors on nonideal solid surfaces, similar to the definition of droplets' θms on solid surfaces. The feasibility and accuracy of the proposed θms have been evidenced by recording the bubbles' contacting behaviors on solid surfaces with varied wettabilities. In addition, it was found that the contact angle hysteresis (δ), as the difference between θa and θr, reached its maximum value when θms approached 90°, regardless of the roughness (r) of the substrates. Finally, built on the above concept, the lateral adhesion force (f) of the gas bubble on the solid interface, which worked on the three-phase contact line (TPCL) of an individual bubble on a solid surface against its lateral motion during the bubble advancing or receding process, was described quantitatively by combining θa, θr, and the liquid-gas interfacial tension (γlg). Experimental and theoretical data jointly confirmed that f reached its maximum value at θms ∼ 90°, namely, a "super-sticky" state, which described the dynamically most sluggish movement of the bubble along the solid surface.

18.
Clin Exp Pharmacol Physiol ; 47(10): 1659-1663, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32469422

RESUMEN

PURPOSE: This retrospective study analyzed the polymorphisms and phenotypic frequencies of CYP2C9, CYP2C19 and CYP2D6 in a Han Chinese population. METHODS: Tests for polymorphisms of CYP2C9, CYP2C19 and CYP2D6 were performed in over 3000 (3099-3931) samples using an Illumina HiSeq X Ten sequencer. Following the guidance of the PharmGKB and PharmVar databases, the polymorphisms of CYP2C9, CYP2C19 and CYP2D6 were transformed into phenotypes, which included ultrarapid metabolizers (UMs), rapid metabolizers (RMs), normal metabolizers (NMs), intermediate metabolizers (IMs) and poor metabolizers (PMs). RESULTS: A total of 3122 samples were tested for polymorphisms in CYP2C9 and the overall polymorphism frequency was found to be 8.8%; the phenotypic frequency for CYP2C9 was 91.2% NMs, 8.23% IMs and 0.16%, PMs. The overall polymorphism frequency of CYP2C19 was tested in 3099 samples and found to be 60.1%; the phenotypic frequency for CYP2C19 was 39.9% NMs, with 1.06% RMs, 45.62% IMs and 13.42% PMs. The overall polymorphism frequency of CYP2D6 was tested in 3931 samples and found to be 88.04%; the phenotypic frequency of CYP2D6 was 95.43% NMs, 3.35% IMs and 0.52% PMs. Using 2690 samples, the polymorphisms and phenotypic distributions of CYP2C9, CYP2C19 and CYP2D6 were examined simultaneously. We found that 96.36% of the samples contained mutations while 66.51% corresponded with phenotypic changes. CONCLUSIONS: Polymorphisms and phenotypic changes of CYP2C9, CYP2C19 and CYP2D6 are relatively frequent in the Han Chinese population. Thus, preemptive pharmacogenetic testing of CYP2C9, CYP2C19 and CYP2D6 should be recommended prior to dosing substrate drugs.


Asunto(s)
Citocromo P-450 CYP2C19/genética , Citocromo P-450 CYP2D6/genética , Fenotipo , China , Humanos
19.
Angew Chem Int Ed Engl ; 59(43): 19095-19101, 2020 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-32686265

RESUMEN

In this work, an artificial electrode/electrolyte (E/E) interface, made by coating the electrode surface with a quaternary ammonium cation (R4 N+ ) surfactant, was successfully developed, leading to a change in the CO2 reduction reaction (CO2 RR) pathway. This artificial E/E interface, with high CO2 permeability, promotes CO2 transportation and hydrogenation, as well as suppresses the hydrogen evolution reaction (HER). Linear and branched surfactants facilitated formic acid and CO production, respectively. Molecular dynamics simulations show that the artificial interface provided a facile CO2 diffusion pathway. Moreover, density-functional theory (DFT) calculations revealed the stabilization of the key intermediate, OCHO*, through interactions with R4 N+ . This strategy might also be applicable to other electrocatalytic reactions where gas consumption is involved.

20.
Small ; 15(46): e1904043, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31529772

RESUMEN

Electrocatalytic hydrogen evolution reaction (HER) is an efficient way to generate hydrogen fuel for the storage of renewable energy. Currently, the widely used Pt-based catalysts suffer from high costs and limited electrochemical stability; therefore, developing an efficient alternative catalyst is very urgent. Herein, one pot hydrothermal synthesis is reported of amorphous ruthenium-sulfide (RuSx ) nanoparticles (NPs) supported on sulfur-doped graphene oxide (GO). The as-obtained composite serves as a Pt-like HER electrocatalyst. Achieving a current density of -10 mA cm-2 only requires a small overpotential (-31, -46, and -58 mV in acidic, neutral, and alkaline electrolyte, respectively) with high durability. The isolated Ru active site inducing Volmer-Heyrovsky mechanism in the RuSx NPs is demonstrated by the Tafel analysis and X-ray absorption spectroscopy characterization. Theoretical simulation indicates the isolated Ru site exhibits Pt-like Gibbs free energy of hydrogen adsorption (-0.21 eV) therefore generating high intrinsic HER activity. Moreover, the strong bonding between the RuSx and S-GO, as well as pH tolerance of RuSx are believed to contribute to the high stability. This work shows a new insight for amorphous materials and provides alternative opportunities in designing advanced electrocatalysts with low-cost for HER in the hydrogen economy.

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