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1.
Small ; : e2311881, 2024 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-38372502

RESUMEN

Shaping covalent organic frameworks (COFs) into macroscopic objects with robust mechanical properties and hierarchically porous structure is of great significance for practical applications but remains formidable and challenging. Herein, a general and scalable protocol is reported to prepare ultralight and robust pure COF fiber aerogels (FAGs), based on the epitaxial growth synergistic assembly (EGSA) strategy. Specifically, intertwined COF nanofibers (100-200 nm) are grown in situ on electrospinning polyacrylonitrile (PAN) microfibers (≈1.7 µm) containing urea-based linkers, followed by PAN removal via solvent extraction to obtain the hollow COF microfibers. The resultant COF FAGs possess ultralow density (14.1-15.5 mg cm-3 ) and hierarchical porosity that features both micro-, meso-, and macropores. Significantly, the unique interconnected structure composed of nanofibers and hollow microfibers endows the COF FAGs with unprecedented mechanical properties, which can fully recover at 50% strain and be compressed for 20 cycles with less than 5% stress degradation. Moreover, the aerogels exhibit excellent capacity for organic solvent absorption (e.g., chloroform uptake of >90 g g-1 ). This study opens new avenues for the design and fabrication of macroscopic COFs with excellent properties.

2.
Environ Sci Technol ; 58(2): 1399-1409, 2024 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-38165309

RESUMEN

Graphene oxide (GO) membranes enabled by subnanosized diffusion channels are promising to separate small species in membrane distillation (MD). However, the challenge of effectively excluding small volatiles in MD persists due to the severe swelling and subsequent increase in GO interlamination spacing upon direct contact with the hot feed. To address this issue, we implemented a design in which a polymer is confined between the GO interlaminations, creating predominantly 2D nanochannels centered around 0.57 nm with an average membrane pore size of 0.30 nm. Compared to the virginal GO membrane, the polymer-intercalated GO membrane exhibits superior antiswelling performance, particularly at a high feed temperature of 60 °C. Remarkably, the modified membrane exhibited a high flux of approximately 52 L m-2 h-1 and rejection rates of about 100% for small ions and 98% for volatile phenol, with a temperature difference of 40 °C. Molecular dynamics simulations suggest that the sieving mechanisms for ions and volatiles are facilitated by the narrowed nanochannels within the polymer network situated between the 2D nanochannels of GO interlaminations. Concurrently, the unrestricted permeation of water molecules through the multinanochannel GO membrane encourages high-flux desalination of complex hypersaline wastewater.


Asunto(s)
Destilación , Grafito , Polímeros , Difusión , Agua
3.
BMC Plant Biol ; 23(1): 463, 2023 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-37794352

RESUMEN

BACKGROUND: Rehmannia glutinosa is a rich source of terpenoids with a high medicinal reputation. The present study compared dedifferentiated cells (DDCs) and cambial meristematic cells (CMCs) cell cultures of R. glutinosa for terpenoid (catalpol) and indole alkaloid (IA) biosynthesis. In this regard, we used widely targeted metabolomics and transcriptome sequencing approaches together with the comparison of cell morphology, cell death (%), and catalpol production at different time points. RESULTS: We were able to identify CMCs based on their morphology and hypersensitivity to zeocin. CMCs showed higher dry weight content and better catalpol production compared to DDCs. The metabolome analysis revealed higher concentrations of IA, terpenoids, and catalpol in CMCs compared to DDCs. The transcriptome sequencing analysis showed that a total of 27,201 genes enriched in 139 pathways were differentially expressed. The higher catalpol concentration in CMCs is related to the expression changes in genes involved in acetyl-CoA and geranyl-PP biosynthesis, which are precursors for monoterpenoid biosynthesis. Moreover, the expressions of the four primary genes involved in monoterpenoid biosynthesis (NMD, CYP76A26, UGT6, and CYP76F14), along with a squalene monooxygenase, exhibit a strong association with the distinct catalpol biosynthesis. Contrarily, expression changes in AADC, STR, and RBG genes were consistent with the IA biosynthesis. Finally, we discussed the phytohormone signaling and transcription factors in relation to observed changes in metabolome. CONCLUSIONS: Overall, our study provides novel data for improving the catalpol and IA biosynthesis in R. glutinosa.


Asunto(s)
Rehmannia , Rehmannia/genética , Rehmannia/metabolismo , Meristema/metabolismo , Glucósidos Iridoides/metabolismo , Alcaloides Indólicos/metabolismo
4.
Langmuir ; 39(48): 17366-17377, 2023 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-37971405

RESUMEN

The urgent need to efficiently and rapidly decontaminate uranium contamination in aquatic environments underscores its significance for ecological preservation and environmental restoration. Herein, a series of titanium-doped zirconium-based metal-organic frameworks were meticulously synthesized through a stepwise process. The resultant hybrid bimetallic materials, denoted as NU-Zr-n%Ti, exhibited remarkable efficiency in eliminating uranium (U (VI)) from aqueous solution. Batch experiments were executed to comprehensively assess the adsorption capabilities of NU-Zr-n%Ti. Notably, the hybrid materials exhibited a substantial increase in adsorption capacity for U (VI) compared to the parent NU-1000 framework. Remarkably, the optimized NU-Zr-15%Ti displayed a noteworthy adsorption capacity (∼118 mg g-1) along with exceptionally rapid kinetics at pH 4.0, surpassing that of pristine NU-1000 by a factor of 10. This heightened selectivity for U (VI) persisted even when diverse ions exist. The dominant mechanisms driving this high adsorption capacity were identified as the robust electrostatic attraction between the negatively charged surface of NU-Zr-15%Ti and positively charged U (VI) species as well as surface complexation. Consequently, NU-Zr-15%Ti emerges as a promising contender for addressing uranium-laden wastewater treatment and disposal due to its favorable sequestration performance.

5.
Environ Sci Technol ; 57(19): 7612-7623, 2023 05 16.
Artículo en Inglés | MEDLINE | ID: mdl-37104662

RESUMEN

Hypersaline wastewater treatment using membrane distillation (MD) has gained significant attention due to its ability to completely reject nonvolatile substances. However, a critical limitation of current MD membranes is their inability to intercept volatile substances owing to their large membrane pores. Additionally, the strong interaction between volatile substances and MD membranes underwater tends to cause membrane wetting. To overcome these challenges, we developed a dual-layer thin film composite (TFC) Janus membrane through electrospinning and sequential interfacial polymerization of a polyamide (PA) layer and cross-linking a polyvinyl alcohol/polyacrylic acid (PP) layer. The resulting Janus membrane exhibited high flux (>27 L m-2 h-1), salt rejection of ∼100%, phenol rejection of ∼90%, and excellent resistance to wetting and fouling. The interlayered interface between the PA and PP layer allowed the sieve of volatile substances by limiting their dissolution-diffusion, with the increasing hydrogen bond network formation preventing their transport. In contrast, small water molecules with powerful dynamics were permeable through the TFC membrane. Both experimental and molecular dynamics simulation results elucidated the sieving mechanism. Our findings demonstrate that this type of TFC Janus membrane can serve as a novel strategy to design next-generation MD membranes against volatile and non-volatile contaminants, which can have significant implications in the treatment of complex hypersaline wastewater.


Asunto(s)
Destilación , Membranas Artificiales , Humectabilidad , Aguas Residuales , Agua , Nylons/química
6.
Environ Res ; 237(Pt 2): 117014, 2023 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-37652216

RESUMEN

In recent years, bioleaching has emerged as a cost-effective technology for enhancing the dewaterability of sludge. However, the lengthy treatment time involved in sludge bioleaching processes limits daily treatment capacity for sludge. Here, a novel approach was developed through a short time of sludge bioleaching with A. ferrooxidans LX5 (A. f) and A. thiooxidans TS6 (A. t) followed by polyferric sulfate (PFS) flocculation (A. f + A. t + PFS). After 12.5 h of the A. f + A. t + PFS treatment (30% A. f, 10% A. t, 40 mg/g DS S0, 60 mg/g DS FeSO4•7H2O, and 120 mg/g DS PFS), the reduction efficiency of specific resistance to filtration (SRF) and sludge cake moisture content reached 94.0% and 11.6%, respectively, which were comparable to the results achieved through 24 h of completed bioleaching treatment. In pilot-scale applications, the mechanical dewatering performance was notably improved following A. f + A. t + PFS treatment, with the low moisture content of the treated sludge cake (∼59.2%). This study provides new insights into the A. f + A. t + PFS process and holds potential for developing efficient and promising sludge dewatering strategies in engineering application.

7.
Health Expect ; 26(6): 2191-2204, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37641530

RESUMEN

INTRODUCTION: Patient engagement, encompassing both patient experience and opportunities for involvement in care, has been associated with increased patient satisfaction and the overall quality of care. Despite its importance, there is limited knowledge regarding patient engagement in the transition from nondialysis-dependent chronic kidney disease (CKD) to dialysis-dependent treatment. This systematic review employs meta-ethnography to synthesize findings from qualitative studies examining patients' experiences of engagement during this transition, with the aim of developing a comprehensive theoretical understanding of patient engagement in the transition from nondialysis-dependent CKD to dialysis. METHODS: A systematic search of six databases, namely the Cochrane Library, PsycINFO, Scopus, Embase, PubMed and Web of Science was conducted to identify eligible articles published between 1990 and 2022. Meta-ethnography was utilized to translate and synthesize the findings and develop a novel theoretical interpretation of 'patient engagement' during the transition to dialysis. RESULTS: A total of 24 articles were deemed eligible for review, representing 21 studies. Patient engagement during a transition to dialysis was found to encompass three major domains: psychosocial adjustment, decision-making and engagement in self-care. These three domains could be experienced as an iterative and mutually reinforcing process, guiding patients toward achieving control and proficiency in their lives as they adapt to dialysis. Additionally, patient engagement could be facilitated by factors including patients' basic capability to engage, the provision of appropriate education, the establishment of supportive relationships and the alignment with values and resources. CONCLUSIONS: The findings of this review underscore the necessity of involving patients in transitional dialysis care, emphasizing the need to foster their engagement across multiple domains. Recommendations for future interventions include the provision of comprehensive support to enhance patient engagement during this critical transition phase. Additional research is warranted to explore the effects of various facilitators at different levels. PATIENT OR PUBLIC CONTRIBUTION: The studies included in our review involved 633 participants (547 patients, 14 family members, 63 healthcare providers and 9 managers). Based on their experiences, views and beliefs, we developed a deeper understanding of patient engagement and how to foster it in the future.


Asunto(s)
Diálisis Renal , Insuficiencia Renal Crónica , Humanos , Participación del Paciente , Antropología Cultural , Investigación Cualitativa , Insuficiencia Renal Crónica/terapia
8.
Genome Res ; 29(5): 798-808, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30940689

RESUMEN

Here, we describe single-tube long fragment read (stLFR), a technology that enables sequencing of data from long DNA molecules using economical second-generation sequencing technology. It is based on adding the same barcode sequence to subfragments of the original long DNA molecule (DNA cobarcoding). To achieve this efficiently, stLFR uses the surface of microbeads to create millions of miniaturized barcoding reactions in a single tube. Using a combinatorial process, up to 3.6 billion unique barcode sequences were generated on beads, enabling practically nonredundant cobarcoding with 50 million barcodes per sample. Using stLFR, we demonstrate efficient unique cobarcoding of more than 8 million 20- to 300-kb genomic DNA fragments. Analysis of the human genome NA12878 with stLFR demonstrated high-quality variant calling and phase block lengths up to N50 34 Mb. We also demonstrate detection of complex structural variants and complete diploid de novo assembly of NA12878. These analyses were all performed using single stLFR libraries, and their construction did not significantly add to the time or cost of whole-genome sequencing (WGS) library preparation. stLFR represents an easily automatable solution that enables high-quality sequencing, phasing, SV detection, scaffolding, cost-effective diploid de novo genome assembly, and other long DNA sequencing applications.


Asunto(s)
Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Secuenciación Completa del Genoma/métodos , Análisis Costo-Beneficio , Diploidia , Biblioteca de Genes , Genoma Humano , Genómica , Haplotipos/genética , Secuenciación de Nucleótidos de Alto Rendimiento/economía , Humanos , Secuenciación Completa del Genoma/economía
9.
Opt Express ; 30(20): 36394-36402, 2022 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-36258568

RESUMEN

We experimentally demonstrate an integrated visible light modulator at 532 nm on the thin-film lithium niobate platform. The waveguides on such platform feature a propagation loss of 2.2 dB/mm while a grating for fiber interface has a coupling loss of 5 dB. Our fabricated modulator demonstrates a low voltage-length product of 1.1 V·cm and a large electro-optic bandwidth with a roll-off of -1.59 dB at 25 GHz for a length of 3.3 mm. This device offers a compact and large bandwidth solution to the challenge of integrated visible wavelength modulation in lithium niobate and paves the way for future small-form-factor integrated systems at visible wavelengths.

10.
Environ Sci Technol ; 56(12): 8833-8843, 2022 06 21.
Artículo en Inglés | MEDLINE | ID: mdl-35618660

RESUMEN

Single oxygen-based advanced oxidation processes (1O2-AOPs) exhibit great prospects in selective degradation of organic pollutants. However, efficient production of 1O2 via tailored design of catalysts to achieve selective oxidation of contaminants remains challenging. Herein, we develop a simple strategy to regulate the components and coordination of Co-N-C catalysts at the atomic level by adjusting the Zn/Co ratio of bimetallic zeolitic imidazolate frameworks (ZnxCo1-ZIFs). Zn4Co1-C demonstrates 98% selective removal of phenol in the mixed phenol/benzoic acid (phenol/BA) solutions. Density functional theory calculations and experiments reveal that more active CoN4 sites are generated in Zn4Co1-C, which are beneficial to peroxymonosulfate activation to generate 1O2. Furthermore, the correlation between the origin of selectivity and well-defined catalysts is systematically investigated by the electron paramagnetic resonance test and quenching experiments. This work may provide novel insights into selective removal of target pollutants in a complicated water matrix.


Asunto(s)
Contaminantes Ambientales , Catálisis , Oxígeno , Peróxidos , Fenoles , Agua
11.
Int J Med Sci ; 19(14): 2033-2043, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36483595

RESUMEN

Hepatocellular carcinoma (HCC) is one of the most common and serious types of cancer worldwide, with high incidence and mortality rates. Circular RNAs (circRNAs) are a novel class of non-coding RNA with important biological functions. In recent years, multiple circRNAs have been found to be involved in the biological processes of tumorigenesis and tumor development. Increasing evidence has shown that circRNAs also play a crucial role in the occurrence and development of HCC. However, the specific molecular mechanism of circRNAs in HCC has not been fully elucidated. The present review systematically summarized the classification and basic characteristics of circRNAs, their biological functions and their role in the occurrence and development of HCC. By summarizing the previous studies on circRNAs in HCC, this study aimed to indicate potential approaches to improving the early diagnosis and treatment of HCC.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , ARN Circular/genética , Carcinoma Hepatocelular/genética , Relevancia Clínica , Neoplasias Hepáticas/genética
12.
BMC Health Serv Res ; 22(1): 1338, 2022 Nov 11.
Artículo en Inglés | MEDLINE | ID: mdl-36368997

RESUMEN

BACKGROUND: The Normalization MeAsure Development (NoMAD) is a brief quantitative tool based on the Normalization Process Theory (NPT), which can measure the implementation process of new technologies and complex interventions. The aim of our study was to translate and culturally adapt the NoMAD into Chinese, and to evaluate the psychometric properties of the Chinese version of NoMAD. METHODS: According to the NoMAD translation guideline, we undertook forward translation, backward translation, and compared these translations to get a satisfactory result, then we performed cognitive interviews to achieve cross-culture adaptation. And the psychometric properties of the final version were evaluated among clinical nurses who used the pressure injuries management system via WeChat mini-program at a tertiary hospital in northwestern China. RESULTS: A total of 258 nurses were enrolled in our study, and the response rate was 92.1%. The Cronbach's alpha of four dimensions were as follow: Coherence (0.768), Cognitive Participation (0.904), Collective Action (0.820), and Reflexive Monitoring (0.808). The overall internal consistency was 0.941. The confirmatory factor analysis results showed a good fit for its theoretical structure (CFI = 0.924, TLI = 0.910, RMSEA = 0.0079, SRMSR = 0.046, χ2/df = 2.61). The item-level content validity index ranged from 0.857 to 1, and the scale-level content validity index was 0.95. There were positive correlations between four constructs scores and three general normalization scores. CONCLUSIONS: The Chinese version of NoMAD is a reliable and valid tool to evaluate the implementation process of innovations.


Asunto(s)
Traducción , Traducciones , Humanos , Reproducibilidad de los Resultados , Encuestas y Cuestionarios , Psicometría/métodos , China
13.
J Asian Nat Prod Res ; 24(6): 577-588, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34292106

RESUMEN

Dimethyl itaconate (DMI) is an analog of dimethyl fumarate (DMF), an approved NF-E2-related Factor 2 (Nrf2) activator for multiple sclerosis. This study evaluated the potential of DMI as an anti-inflammatory agent by comparing DMI with DMF in electrophilicity, Nrf2 activation, and anti-inflammation in vitro. The results showed that DMI was less electrophilic but better at inducing a durable activation of Nrf2 when compared with DMF. However, DMI demonstrated poor anti-inflammatory effects in Jurkat cells, bone marrow-derived dendritic cells, and RAW264.7 cells. Our study suggested that DMI was a potent electrophilic Nrf2 activator but was probably not a promising anti-inflammatory agent.


Asunto(s)
Dimetilfumarato , Factor 2 Relacionado con NF-E2 , Antiinflamatorios/farmacología , Dimetilfumarato/farmacología , Dimetilfumarato/uso terapéutico , Humanos , Inflamación/tratamiento farmacológico , Estructura Molecular , Factor 2 Relacionado con NF-E2/metabolismo , Succinatos
14.
Molecules ; 27(21)2022 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-36364210

RESUMEN

Previously reported (S)-5'-C-aminopropyl-2'-arabinofluoro-thymidine (5ara-T) and newly synthesized (S)-5'-C-aminopropyl-2'-arabinofluoro-5-methyl-cytidine (5ara-MeC) analogs were incorporated into a series of antisense gapmers containing multiple phosphorothioate (PS) linkages and locked nucleic acids (LNAs) in their wing regions. The functional properties of the gapmers were further evaluated in vitro. Compared with the positive control, for the LNA-wing full PS gapmer without 5ara modification, it was revealed that each gapmer could have a high affinity and be thermally stable under biological conditions. Although the cleavage pattern was obviously changed; gapmers with 5ara modification could still efficiently activate E. coli RNase H1. In addition, incorporating one 5ara modification into the two phosphodiester linkages could reverse the destabilization in enzymatic hydrolysis caused by fewer PS linkages. In vitro cellular experiments were also performed, and the Lipofectamine® 2000 (LFA)+ group showed relatively higher antisense activity than the LFA-free group. KN5ara-10, which contains fewer PS linkages, showed similar or slightly better antisense activity than the corresponding full PS-modified KN5ara-3. Hence, KN5ara-10 may be the most promising candidate for KNTC2-targeted cancer therapy.


Asunto(s)
Nucleósidos , Oligonucleótidos Antisentido , Oligonucleótidos Antisentido/genética , Oligonucleótidos Antisentido/farmacología , Oligonucleótidos Antisentido/metabolismo , Escherichia coli/metabolismo
15.
Molecules ; 27(20)2022 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-36296725

RESUMEN

In this work, polyacrylonitrile/aminated polymeric nanosphere (PAN/APN) nanofibers were prepared by electrospinning of monodispersed aminated polymeric nanospheres (APNs) for removal of Cr(VI) from aqueous solution. Characterization results showed that obtained PAN/APNs possessed nitrogen functionalization. Furthermore, the adsorption application results indicated that PAN/APN nanofibers exhibited a high adsorption capacity of 556 mg/g at 298 K for Cr(VI) removal. The kinetic data showed that the adsorption process fits the pseudo-second order. A thermodynamic study revealed that the adsorption of Cr(VI) was spontaneous and endothermic. The coexisting ions Na+, Ca2+, K+, Cl-, NO3- and PO43- had little influence on Cr(VI) adsorption, while SO42- in solution dramatically decreased the removal performance. In the investigation of the removal mechanism, relative results indicated that the adsorption behavior possibly involved electrostatic adsorption, redox reaction and chelation. PAN/APN nanofibers can detoxify Cr(VI) to Cr(III) and subsequently chelate Cr(III) on its surface. The unique structure and nitrogen functionalization of PAN/APN nanofibers make them novel and prospective candidates in heavy metal removal.


Asunto(s)
Metales Pesados , Nanofibras , Nanosferas , Contaminantes Químicos del Agua , Nanofibras/química , Contaminantes Químicos del Agua/química , Cromo/química , Adsorción , Cinética , Polímeros , Iones , Nitrógeno
16.
Neurobiol Dis ; 153: 105315, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33636390

RESUMEN

It is increasingly recognized that blood-spinal cord barrier (BSCB) breakdown is a hallmark of amyotrophic lateral sclerosis (ALS). BSCB integrity is disrupted prior to disease onset. Occludin, as the functional component of the endothelial barrier, is downregulated in mouse models expressing ALS-linked superoxide dismutase-1 (SOD1) mutants. However, the molecular mechanisms underlying the regulation of occludin expression remain elusive. Here, using SOD1G93A transgenic mice and endothelial cells expressing SOD1 mutants of different biochemical characteristics, we found that the SOD1 mutation disrupted endothelial barrier integrity and that the occludin expression level was downregulated with disease progression. Our mechanistic studies revealed that abnormal reactive oxygen species (ROS) in mutant SOD1-expressing cells induced occludin phosphorylation, which facilitated the subsequent occludin ubiquitination mediated by the E3 ligase ITCH. Moreover, ubiquitinated occludin interacted with Eps15 to initiate its internalization, then trafficked to Rab5-positive vesicles and be degraded by proteasomes, resulting in a reduction in cell surface localization and total abundance. Notably, either ITCH or Eps15 knockdown was sufficient to rescue occludin degradation and ameliorate endothelial barrier disruption. In conclusion, our study reveals a novel mechanism of occludin degradation mediated by ALS-causing SOD1 mutants and demonstrates a role for occludin in regulating BSCB integrity.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/metabolismo , Esclerosis Amiotrófica Lateral/genética , Barrera Hematoencefálica/metabolismo , Células Endoteliales/metabolismo , Ocludina/metabolismo , Proteínas Represoras/metabolismo , Superóxido Dismutasa-1/genética , Ubiquitina-Proteína Ligasas/metabolismo , Proteínas de Unión al GTP rab5/metabolismo , Esclerosis Amiotrófica Lateral/metabolismo , Animales , Endocitosis/genética , Humanos , Técnicas In Vitro , Ratones , Ratones Transgénicos , Mutación , Fosforilación/genética , Vesículas Transportadoras/metabolismo , Ubiquitinación/genética
17.
Environ Sci Technol ; 53(19): 11383-11390, 2019 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-31483614

RESUMEN

Surface-adsorbed active species are intermediates with strong activities in heterogeneous catalytic reactions. Effective stabilization of these intermediates is crucial to improve the catalytic performance. Here, we demonstrated highly active bimetallic palladium-indium (Pd-In) nanoparticles (NPs) that can stabilize atomic H* on the surface and show efficient electrocatalytic reduction performance toward bromate. The optimal atomic ratio of Pd to In was investigated with the aim of efficient formation and strong stabilization of H*, thus facilitating the reduction and decontamination of carcinogenic bromate. Pd2In3 was the most active catalyst, with a high rate constant of 0.029 min-1, whereas the rate constant for monometallic Pd NPs was only 0.009 min-1. Density functional theory calculations suggest that Pd2In3 NPs decrease the work function and provide strong H* stabilization ability. By employing a flow-through electrode coated with Pd2In3 NPs to enhance the mass transport, the utilization of H* could be boosted and the reduction kinetics increased up to 7.5 times.


Asunto(s)
Nanopartículas , Paladio , Electrodos , Hidrógeno , Indio
18.
Environ Sci Technol ; 52(13): 7477-7485, 2018 07 03.
Artículo en Inglés | MEDLINE | ID: mdl-29883543

RESUMEN

Hierarchical three-dimensional architectures of granphene-based materials with tailored microstructure and functionality exhibit unique mass transport behaviors and tunable active sites for various applications. The micro- /nanochannels in the porous structure can act as micro- /nano- reactors, which optimize the transport and conversion of contaminants. However, the size-effects of the micro- /nanochannels, which are directly related to its performance in electrochemical processes, have not been explored. Here, using lamellar-structured graphene films as electrodes, we demonstrate that the interlayer spacing (range from ∼84 nm to ∼2.44 µm) between graphene nanosheets governs the mass transport and electron transfer in electrochemical processes; subsequently influence the water decontamination performances. The microchannel (interlayer spacing = ∼2.44 µm) can provide higher active surface areas, but slow reaction kinetics. Densely packed graphene nanosheets (interlayer spacing = ∼280 nm), which possessed better electron conductivity and could provide higher surface-area-to-volume ratio in narrow nanochannels (7.14 µm-1), achieved the highest reaction kinetics. However, the ion-accessible surface area was decreased in highly dense films (interlayer spacing = ∼84 nm) due to serious interlayer stacking of graphene nanosheets, thereby leading poor reaction kinetics. These results demonstrate the size-effect of nanochannels in porous materials and highlight the importance of controlling mass transport and electron transfer for optimal electrochemical performance, enabling a deep understanding of the benefits and utilization of these hierarchical three-dimensional architectures in water purification.


Asunto(s)
Grafito , Purificación del Agua , Electrodos , Porosidad , Agua
19.
Org Biomol Chem ; 15(16): 3455-3465, 2017 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-28368067

RESUMEN

Selective BRafV600E inhibitors with DFG-in conformation have been proven effective against a subset of melanoma. However, representative inhibitor vemurafenib rapidly acquires resistance in the BRafWT cells through a CRaf or BRafWT dependent manner. Simultaneous targeting of all subtypes of Raf proteins offers the prospect of enhanced efficacy as well as reduced potential for acquired resistance. Herein, we describe the design and characterization of a series of compounds I-01-I-22, based on a pyrimidine scaffold with DFG-out conformation as Pan-Raf inhibitors. Among them, I-15 binds to all Raf protomers with IC50 values of 12.6 nM (BRafV600E), 30.1 nM (ARaf), 19.7 nM (BRafWT) and 17.5 nM (CRaf) and demonstrates cellular activity against BRafWT phenotypic melanoma and BRafV600E phenotypic colorectal cancer cells. The western blot results for the P-Erk inhibition in human melanoma SK-Mel-2 cell line showed that I-15 inhibited the proliferation of the SK-Mel-2 cell line at concentrations as low as 400 nM, without paradoxical activation of Erk as vemurafenib, which supported that I-15 may become a good candidate compound to overcome the resistance of melanoma induced by vemurafenib. I-15 also has a favorable pharmacokinetic profile in rats. Rational design, synthesis, SAR, lead selection and evaluation of the key compounds studied are described.


Asunto(s)
Diseño de Fármacos , Resistencia a Antineoplásicos/efectos de los fármacos , Inhibidores de Proteínas Quinasas/síntesis química , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Proto-Oncogénicas B-raf/antagonistas & inhibidores , Animales , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Técnicas de Química Sintética , Humanos , Concentración 50 Inhibidora , Masculino , Modelos Moleculares , Conformación Proteica , Inhibidores de Proteínas Quinasas/química , Inhibidores de Proteínas Quinasas/farmacocinética , Proteínas Proto-Oncogénicas B-raf/química , Ratas
20.
Phytopathology ; 106(8): 807-13, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26976730

RESUMEN

Tubulins are the proposed target of clinically relevant anticancer drugs, anthelmintic, and fungicide. ß2-tubulin of the plant pathogen Fusarium graminearum was considered as the target of benzimidazole compounds by homology modeling in our previous work. In this study, α1-, α2-, and ß2-tubulin of F. graminearum were produced in Escherichia coli. Three benzimidazole compounds (carbendazim, benomyl, and thiabendazole) interacted with the recombinant ß2-tubulin and reduced the maximum fluorescence intensity of 2 µM ß2-tubulin 47, 50, and 25%, respectively, at saturation of compound-tubulin complexes. Furthermore, carbendazim significantly inhibited the polymerization of α1-/ß2-tubulins and α2-/ß2-tubulins 90.9 ± 0.4 and 93.5 ± 0.05%, respectively, in vitro. A similar result appeared with benomyl on the polymerization of α1-/ß2-tubulins and α2-/ß2-tubulins at 89.9 ± 0.1% and 92.6 ± 1.2% inhibition ratios, respectively. In addition, thiabendazole inhibited 81.6 ± 1% polymerization of α1-/ß2-tubulins, whereas it had less effect on α2-/ß2-tubulin polymerization, with 20.1 ± 1.9% inhibition ratio. However, the three compounds cannot destabilize the polymerized microtubule. To illuminate the issue, mapping the carbendazim binding sites and ß/α subunit interface on ß/α-tubulin complexes by homology modeling showed that the two domains were closed to each other. Understanding the nature of the interaction between benzimidazole compounds and F. graminearum tubulin is fundamental for the development of tubulin-specific anti-F. graminearum compounds.


Asunto(s)
Bencimidazoles/farmacología , Fungicidas Industriales/farmacología , Fusarium/efectos de los fármacos , Microtúbulos/fisiología , Tubulina (Proteína)/fisiología , Benomilo/farmacología , Carbamatos/farmacología , Proteínas Fúngicas/metabolismo , Regulación Fúngica de la Expresión Génica/efectos de los fármacos , Modelos Moleculares , Polimerizacion/efectos de los fármacos , Unión Proteica , Conformación Proteica , Replegamiento Proteico , Proteínas Recombinantes , Tiabendazol/farmacología
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