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1.
Pharm Res ; 41(9): 1797-1809, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39251485

RESUMEN

PURPOSE: Currently, for veterinary oral formulations containing one or more active pharmaceutical ingredient (API) that are not systemically absorbed and act locally within the gastrointestinal (GI) tract, the use of terminal clinical endpoint bioequivalence (BE) studies is the only option for evaluating product BE. This investigation explored the use of a totality of evidence approach as an alternative to these terminal studies. METHODS: Three formulations of tablets containing ivermectin plus praziquantel were manufactured to exhibit distinctly different in vitro release characteristics. Because these APIs are highly permeable, plasma drug concentrations served as a biomarker of in vivo dissolution. Tablets were administered to 27 healthy Beagle dogs (3-way crossover) and the rate and extent of exposure of each API for each formulation was compared in a pairwise manner. These results were compared to product relative in vitro dissolution profiles in 3 media. In vivo and in vitro BE predictions were compared. RESULTS: In vivo/in vitro inconsistencies in product relative performance were observed with both compounds when considering product performance across the 3 dissolution media. Formulation comparisons flagged major differences that could explain this outcome. CONCLUSIONS: The finding of an inconsistent in vivo/in vitro relationship confirmed that in vitro dissolution alone cannot assure product BE for veterinary locally acting GI products. However, when combined with a comparison of product composition and manufacturing method, this totality of evidence approach can successfully alert scientists to potential therapeutic inequivalence, thereby supporting FDA's efforts to Replace, Reduce, and/or Refine terminal animal studies.


Asunto(s)
Estudios Cruzados , Ivermectina , Comprimidos , Equivalencia Terapéutica , Perros , Animales , Ivermectina/farmacocinética , Ivermectina/administración & dosificación , Praziquantel/farmacocinética , Praziquantel/administración & dosificación , Praziquantel/química , Solubilidad , Administración Oral , Masculino , Drogas Veterinarias/farmacocinética , Drogas Veterinarias/administración & dosificación , Química Farmacéutica/métodos , Liberación de Fármacos , Femenino , Medicamentos a Granel
2.
Ann Med ; 56(1): 2329261, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-39316667

RESUMEN

BACKGROUND: Indigo naturalis is effective against psoriasis. Indigo, indirubin and tryptanthrin, the main active components of indigo naturalis, have anti-inflammatory properties. OBJECTIVE: To evaluate the efficacy and safety of indigo naturalis and its active components in the treatment of psoriasis. METHODS: Seven databases were searched for studies of indigo naturalis and its active components for the treatment of psoriasis. RESULTS: The findings demonstrated a higher response rate in the Chinese herbal medicine (CHM) formula groups than in the control group for Psoriasis Area and Severity Index 60 (PASI60) (Rate difference [RD] = 0.22, p < .0001). Among all adverse events, only the incidence of gastrointestinal adverse reactions was higher in the CHM formula group than in the control group (RD = 0.09, p < .0001). In preclinical in vivo studies, indirubin showed better performance in improving the phenotype of psoriasis-like mice compared to that in controls, including the PASI score (mean difference [MD] = -3.58, p < .0001), epidermal thickness (MD = -29.13, p < .0001), interleukin-(IL) 17 A mRNA expression (MD = -2.27, p = .0066) and IL-23 mRNA (MD = -5.36, p = .01). CONCLUSION: Indigo naturalis combined with conventional treatments is useful for treating psoriasis. Indigo naturalis display anti-proliferative, anti-inflammatory and anti-angiogenic effects by regulating the TAK1, JAK3/STAT3, Wnt/ß-catenin, Akt/PKB, FAK and AP-1/c-Jun pathway.


Indigo naturalis, a Chinese herb and its main active components, indigo, indirubin and tryptanthrin are effective in treating psoriasis.Indigo naturalis, indirubin, indigo and tryptanthrin have anti-proliferative, anti-inflammatory and anti-angiogenic effects via regulating the TAK1, JAK3/STAT3, Wnt/ß-catenin, Akt/PKB, FAK and AP-1/c-Jun pathways.


Asunto(s)
Medicamentos Herbarios Chinos , Indoles , Psoriasis , Psoriasis/tratamiento farmacológico , Humanos , Animales , Medicamentos Herbarios Chinos/farmacología , Medicamentos Herbarios Chinos/uso terapéutico , Indoles/farmacología , Indoles/uso terapéutico , Ratones , Antiinflamatorios/farmacología , Antiinflamatorios/uso terapéutico , Carmin de Índigo , Indigofera/química , Quinazolinas
3.
Int J Biol Macromol ; 277(Pt 3): 134411, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39097054

RESUMEN

Stress granules (SGs) are membrane-less organelles (MLOs) or cytosolic compartments formed upon exposure to environmental cell stress-inducing stimuli. SGs are based on ribonucleoprotein complexes from a set of cytoplasmic proteins and mRNAs, blocked in translation due to stress cell-induced polysome disassembly. Post-translational modifications (PTMs) such as methylation, are involved in SG assembly, with the methylation writer PRMT1 and its reader TDRD3 colocalizing to SGs. However, the role of this writer-reader system in SG assembly remains unclear. Here, we found that PRMT1 methylates SG constituent RNA-binding proteins (RBPs) on their RGG motifs. Besides, we report that TDRD3, as a reader of asymmetric dimethylarginines, enhances RNA binding to recruit additional RNAs and RBPs, lowering the percolation threshold and promoting SG assembly. Our study enriches our understanding of the molecular mechanism of SG formation by elucidating the functions of PRMT1 and TDRD3. We anticipate that our study will provide a new perspective for comprehensively understanding the functions of PTMs in liquid-liquid phase separation driven condensate assembly.


Asunto(s)
Proteína-Arginina N-Metiltransferasas , Proteínas de Unión al ARN , Gránulos de Estrés , Humanos , Metilación , Unión Proteica , Mapas de Interacción de Proteínas , Procesamiento Proteico-Postraduccional , Proteína-Arginina N-Metiltransferasas/metabolismo , Proteína-Arginina N-Metiltransferasas/genética , Proteínas Represoras/metabolismo , Proteínas Represoras/genética , Proteínas de Unión al ARN/metabolismo , Gránulos de Estrés/metabolismo
4.
J Appl Microbiol ; 135(8)2024 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-39085035

RESUMEN

AIMS: The optimal sampling methods for detecting human papillomavirus (HPV) in male genital sites remain unclear. This study aimed to assess the performance, acceptability, and comfort of two sampling techniques for male genital HPV detection. METHODS AND RESULTS: A total of 490 men aged 18-45 were randomly assigned in a 1:1 ratio to undergo either the rub-brush (nail file followed by swab) or brush-only method (swab only) for sampling at external genitalia sites (PGS) and perineum/perianal (PA) sites. HPV distribution, specimen validity (ß-globin as a quality reference), and participant acceptability and comfort were evaluated between the two sampling methods. The brush-only method demonstrated non-inferiority in detecting 14 high-risk HPV types (16/18/31/33/35/39/45/51/52/56/58/59/66/68) compared to the rub-brush method in both PGS (18.9% vs. 16.9%) and PA (10.5% vs. 11.9%). Although no significant differences were observed in positive rates for other HPV types, the brush-only method had a significantly higher invalid rate in PA (8.5% vs. 1.5%). Approximately 85.0% of participants reported good acceptability and comfort with both sampling methods, regardless of anatomical sites. CONCLUSIONS: This study suggests comparable performance, acceptability and comfort between the two sampling techniques for HPV detection. However, the rub-brush method may offer an advantage in higher sample validity.


Asunto(s)
Papillomaviridae , Infecciones por Papillomavirus , Manejo de Especímenes , Humanos , Masculino , Adulto , Infecciones por Papillomavirus/diagnóstico , Infecciones por Papillomavirus/virología , Manejo de Especímenes/métodos , Persona de Mediana Edad , Adulto Joven , Papillomaviridae/aislamiento & purificación , Adolescente , Genitales Masculinos/virología
5.
Nano Lett ; 24(19): 5714-5721, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38695488

RESUMEN

The structure of solvated Li+ has a significant influence on the electrolyte/electrode interphase (EEI) components and desolvation energy barrier, which are two key factors in determining the Li+ diffusion kinetics in lithium metal batteries. Herein, the "solvent activity" concept is proposed to quantitatively describe the correlation between the electrolyte elements and the structure of solvated Li+. Through fitting the correlation of the electrode potential and solvent concentration, we suggest a "low-activity-solvent" electrolyte (LASE) system for deriving a stable inorganic-rich EEI. Nano LiF particles, as a model, were used to capture free solvent molecules for the formation of a LASE system. This advanced LASE not only exhibits outstanding antidendrite growth behavior but also delivers an impressive performance in Li/LiNi0.8Co0.1Mn0.1O2 cells (a capacity of 169 mAh g-1 after 250 cycles at 0.5 C).

6.
Allergy Asthma Clin Immunol ; 20(1): 16, 2024 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-38395967

RESUMEN

BACKGROUND: Correlations between mitochondrial DNA (mtDNA) and allergic rhinitis (AR) have not been reported before. This study aimed to better understand the mitochondrial genome profile with AR and to investigate the associations between AR in China and the mitochondrial genome at a single variant and gene level. METHODS: Mitochondrial sequencing was conducted on a total of 134 unrelated individual subjects (68 patients with AR, 66 healthy controls) at discovery stage. Heteroplasmy was analyzed using the Mann-Whitney U test. Sequence kernel association tests (SKAT) were conducted to study the association between mitochondrial genes and AR. Single-variant analysis was performed using logistic regression analysis and further validated in 120 subjects (69 patients with AR, 51 healthy controls). Candidate genes were further explored based on differences in mRNA and protein abundance in nasal mucosal tissue. RESULTS: In the discovery stage, 886 variants, including 836 SNV and 50 indels, were identified with mitochondrial sequencing. No statistically significant differences were identified for the mitochondrial heteroplasmy or SKAT analysis between these two groups after applying a Boferroni correction. One nonsynonymous variants, rs3135028 (MT8584.G/A) in ATP6, was related to a reduced risk of AR in both the discovery and validation cohorts. Furthermore, mRNA levels of MT-ATP6 in nasal mucosal tissue were significantly lower in AR individuals than in controls (P < 0.05). CONCLUSIONS: In a two-stage analysis of associations between AR and mtDNA variations, mitochondrial gene maps of Chinese patients with AR indicated that the ATP6 gene was probably associated with AR at the single-variant level.

8.
World J Clin Cases ; 11(34): 8164-8169, 2023 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-38130781

RESUMEN

BACKGROUND: Langerhans cell histiocytosis (LCH) is a rare clonal proliferative disease of Langerhans cells with unknown pathogenesis. An increasing number of clinicians recognize that LCH has a wide clinical spectrum and a highly varied course. Adults rarely develop LCH. Here, we report a case of adult localized LCH. CASE SUMMARY: A 32-year-old woman presented with plaques and ulcers on the vulva and crissum, accompanied by pain that persisted for more than one year. Physical examination revealed a red-infiltrating plaque with ulcerations and exudates in the vulva and crissum. Pathological examination revealed a diffuse infiltration of lymphocytes, eosinophilic granulocytes, and histiocytoid cells in the superficial dermis. Proliferative histiocytoid cells showed mild atypia, partly with kidney-shaped nuclei. Immunohistochemical examination showed that the histiocytoid cells were positive for S100 protein and CD1 and weakly positive for CD68 (20% +), with a Ki-67 index of 30%. Laboratory tests did not reveal any other systemic damage. The patient was diagnosed with adult localized LCH and was prescribed oral prednisone (20 mg) once daily. The skin lesions gradually improved and are still being followed-up. CONCLUSION: Adult localized LCH is rare and must be differentiated from other common conditions.

9.
Adv Mater ; 35(39): e2302828, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37341309

RESUMEN

The lithium-metal anode is a promising candidate for realizing high-energy-density batteries owing to its high capacity and low potential. However, several rate-limiting kinetic obstacles, such as the desolvation of Li+ solvation structure to liberate Li+ , Li0 nucleation, and atom diffusion, cause heterogeneous spatial Li-ion distribution and fractal plating morphology with dendrite formation, leading to low Coulombic efficiency and depressive electrochemical stability. Herein, differing from pore sieving effect or electrolyte engineering, atomic iron anchors to cation vacancy-rich Co1- x S embedded in 3D porous carbon (SAFe/CVRCS@3DPC) is proposed and demonstrated as catalytic kinetic promoters. Numerous free Li ions are electrocatalytically dissociated from the Li+ solvation complex structure for uniform lateral diffusion by reducing desolvation and diffusion barriers via SAFe/CVRCS@3DPC, realizing smooth dendrite-free Li morphologies, as comprehensively understood by combined in situ/ex situ characterizations. Encouraged by SAFe/CVRCS@3DPC catalytic promotor, the modified Li-metal anodes achieve smooth plating with a long lifespan (1600 h) and high Coulombic efficiency without any dendrite formation. Paired with the LiFePO4 cathode, the full cell (10.7 mg cm-2 ) stabilizes a capacity retention of 90.3% after 300 cycles at 0.5 C, signifying the feasibility of using interfacial catalysts for modulating Li behaviors toward practical applications.

10.
J Phys Chem B ; 127(22): 5018-5026, 2023 06 08.
Artículo en Inglés | MEDLINE | ID: mdl-37222424

RESUMEN

Biomolecule condensates formed via liquid-liquid phase separation (LLPS) play crucial roles within various cellular processes. Despite numerous theoretical and experimental discoveries, the general principle by which the protein conformation affects the propensity for LLPS remains poorly understood. Here, we systematically address this issue using a general coarse-grained model of intrinsically disordered proteins (IDPs) with different degrees of intrachain crosslinks. We find that an increased conformation collapse due to higher intrachain crosslink ratio f enhances the thermodynamic stability of protein phase separation and found the critical temperature Tc has a good scaling law with the proteins' average radius of gyration Rg. Such correlation is robust regardless of interaction types and sequence patterns. Strikingly, the growth dynamics of the LLPS process, contrary to the thermodynamic observation, is generally more favored at proteins with extended conformation. Faster condensate growing speed is again observed for higher-f collapsed IDPs, resulting altogether in a nonmonotonic dynamics as a function of f. A phenomenological understanding of the phase behavior is provided by a mean-field model with an effective Flory interaction parameter χ, which is found to have a good scaling law with conformation expansion. Our study shed lights on the general mechanism for understanding and modulation of phase separation with different conformation profiles and may provide new evidence in reconciling the contradictions in thermodynamic- and dynamic-controlled experimental LLPS observations.


Asunto(s)
Proteínas Intrínsecamente Desordenadas , Proteínas Intrínsecamente Desordenadas/metabolismo , Termodinámica , Temperatura , Conformación Proteica
12.
Nat Cell Biol ; 25(1): 79-91, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36536176

RESUMEN

In eukaryotes, end-binding (EB) proteins serve as a hub for orchestrating microtubule dynamics and are essential for cellular dynamics and organelle movements. EB proteins modulate structural transitions at growing microtubule ends by recognizing and promoting an intermediate state generated during GTP hydrolysis. However, the molecular mechanisms and physiochemical properties of the EB1 interaction network remain elusive. Here we show that EB1 formed molecular condensates through liquid-liquid phase separation (LLPS) to constitute the microtubule plus-end machinery. EB1 LLPS is driven by multivalent interactions among different segments, which are modulated by charged residues in the linker region. Phase-separated EB1 provided a compartment for enriching tubulin dimers and other plus-end tracking proteins. Real-time imaging of chromosome segregation in HeLa cells expressing LLPS-deficient EB1 mutants revealed the importance of EB1 LLPS dynamics in mitotic chromosome movements. These findings demonstrate that EB1 forms a distinct physical and biochemical membraneless-organelle via multivalent interactions that guide microtubule dynamics.


Asunto(s)
Proteínas Asociadas a Microtúbulos , Microtúbulos , Humanos , Células HeLa , Proteínas Asociadas a Microtúbulos/genética , Proteínas Asociadas a Microtúbulos/metabolismo , Microtúbulos/metabolismo , Unión Proteica , Tubulina (Proteína)/metabolismo
13.
ACS Nano ; 16(11): 17729-17760, 2022 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-36305602

RESUMEN

Lithium metal anodes are ideal for realizing high-energy-density batteries owing to their advantages, namely high capacity and low reduction potentials. However, the utilization of lithium anodes is restricted by the detrimental lithium dendrite formation, repeated formation and fracturing of the solid electrolyte interphase (SEI), and large volume expansion, resulting in severe "dead lithium" and subsequent short circuiting. Currently, the researches are principally focused on inhibition of dendrite formation toward extending and maintaining battery lifespans. Herein, we summarize the strategies employed in interfacial engineering and current-collector host designs as well as the emerging electrochemical catalytic methods for evolving-accelerating-ameliorating lithium ion/atom diffusion processes. First, strategies based on the fabrication of robust SEIs are reviewed from the aspects of compositional constituents including inorganic, organic, and hybrid SEI layers derived from electrolyte additives or artificial pretreatments. Second, the summary and discussion are presented for metallic and carbon-based three-dimensional current collectors serving as lithium hosts, including their functionality in decreasing local deposition current density and the effect of introducing lithiophilic sites. Third, we assess the recent advances in exploring alloy compounds and atomic metal catalysts to accelerate the lateral lithium ion/atom diffusion kinetics to average the spatial lithium distribution for smooth plating. Finally, the opportunities and challenges of metallic lithium anodes are presented, providing insights into the modulation of diffusion kinetics toward achieving dendrite-free lithium metal batteries.

14.
ACS Nano ; 16(10): 16898-16908, 2022 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-36169299

RESUMEN

A solid electrolyte interphase (SEI) with robust mechanical property and high ionic conductivity is imperative for high-performance lithium metal batteries since it can efficiently impede the growth of notorious lithium dendrites. However, it is difficult to form such a SEI directly from an electrolyte. In this work, a crowding dilutant modified ionic liquid electrolyte (M-ILE) has been developed for this purpose. Simulations and experiments indicate that the 1,2-difluorobenzene (1,2-dfBen) dilutant not only creates a crowded electrolyte environment to promote the interaction of Li+-FSI-, leading to abundant aggregate ion pairs (AGGs), but also participates in the reduction to construct a robust and high ionic-conductive SEI. With this M-ILE, Li/LiFePO4 cells achieve a capacity retention of 96% over 250 cycles with 9.5 mg cm-2 mass loading, and Li/LiNi0.5Co0.2Mn0.3O2 cells also deliver a discharge capacity of 132 mAh g-1 with a high retention of 88% after 100 cycles. Therefore, the use of a crowding diluent is considered to be an efficient way to construct an advanced SEI for a Li anode.

15.
Nano Lett ; 22(19): 8008-8017, 2022 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-36018258

RESUMEN

Lithium metal anode possesses overwhelming capacity and low potential but suffers from dendrite growth and pulverization, causing short lifespan and low utilization. Here, a fundamental novel insight of using single-atomic catalyst (SAC) activators to boost lithium atom diffusion is proposed to realize delocalized deposition. By combining electronic microscopies, time-of-flight secondary ion mass spectrometry, theoretical simulations, and electrochemical analyses, we have unambiguously depicted that the SACs serve as kinetic activators in propelling the surface spreading and lateral redistribution of the lithium atoms for achieving dendrite-free plating morphology. Under the impressive capacity of 20 mA h cm-2, the Li modified with SAC-activator exhibits a low overpotential of ∼50 mV at 5 mA cm-2, a long lifespan of 900 h, and high Coulombic efficiencies during 150 cycles, much better than most literature reports. The so-coupled lithium-sulfur full battery delivers high cycling and rate performances, showing great promise toward the next-generation lithium metal batteries.

16.
Adv Sci (Weinh) ; 9(23): e2202244, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35673962

RESUMEN

Lithium metal is considered as the most prospective electrode for next-generation energy storage systems due to high capacity and the lowest potential. However, uncontrollable spatial growth of lithium dendrites and the crack of solid electrolyte interphase still hinder its application. Herein, Schottky defects are motivated to tune the 4f-center electronic structures of catalysts to provide active sites to accelerate Li transport kinetics. As experimentally and theoretically confirmed, the electronic density is redistributed and affected by the Schottky defects, offering numerous active catalytic centers with stronger ion diffusion capability to guide the horizontal lithium deposition against dendrite growth. Consequently, the Li electrode with artificial electronic-modulation layer remarkably decreases the barriers of desolvation, nucleation, and diffusion, extends the dendrite-free plating lifespan up to 1200 h, and improves reversible Coulombic efficiency. With a simultaneous catalytic effect on the conversions of sulfur species at the cathodic side, the integrated Li-S full battery exhibits superior rate performance of 653 mA h g-1 at 5 C, high long-life capacity retention of 81.4% at 3 C, and a high energy density of 2264 W h kg-1 based on sulfur in a pouch cell, showing the promising potential toward high-safety and long-cycling lithium metal batteries.

17.
Biophys Rep ; 8(2): 55-67, 2022 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-37287828

RESUMEN

Liquid-liquid phase separation (LLPS) has proved to be ubiquitous in living cells, forming membraneless organelles (MLOs) and dynamic condensations essential in physiological processes. However, some underlying mechanisms remain challenging to unravel experimentally, making theoretical modeling an indispensable aspect. Here we present a protocol for understanding LLPS from fundamental physics to detailed modeling procedures. The protocol involves a comprehensive physical picture on selecting suitable theoretical approaches, as well as how and what to interpret and resolve from the results. On the particle-based level, we elaborate on coarse-grained simulation procedures from building up models, identifying crucial interactions to running simulations to obtain phase diagrams and other concerned properties. We also outline field-based theories which give the system's density profile to determine phase diagrams and provide dynamic properties by studying the time evolution of density field, enabling us to characterize LLPS systems with larger time and length scales and to further include other nonequilibrium factors such as chemical reactions.

18.
Plant Physiol ; 187(3): 1250-1266, 2021 11 03.
Artículo en Inglés | MEDLINE | ID: mdl-34618050

RESUMEN

Plants detect neighboring competitors through a decrease in the ratio between red and far-red light (R:FR). This decreased R:FR is perceived by phytochrome photoreceptors and triggers shade avoidance responses such as shoot elongation and upward leaf movement (hyponasty). In addition to promoting elongation growth, low R:FR perception enhances plant susceptibility to pathogens: the growth-defense tradeoff. Although increased susceptibility in low R:FR has been studied for over a decade, the associated timing of molecular events is still unknown. Here, we studied the chronology of FR-induced susceptibility events in tomato (Solanum lycopersicum) plants pre-exposed to either white light (WL) or WL supplemented with FR light (WL+FR) prior to inoculation with the necrotrophic fungus Botrytis cinerea (B.c.). We monitored the leaf transcriptional changes over a 30-h time course upon infection and followed up with functional studies to identify mechanisms. We found that FR-induced susceptibility in tomato is linked to a general dampening of B.c.-responsive gene expression, and a delay in both pathogen recognition and jasmonic acid-mediated defense gene expression. In addition, we found that the supplemental FR-induced ethylene emissions affected plant immune responses under the WL+FR condition. This study improves our understanding of the growth-immunity tradeoff, while simultaneously providing leads to improve tomato resistance against pathogens in dense cropping systems.


Asunto(s)
Botrytis/fisiología , Ciclopentanos/metabolismo , Oxilipinas/metabolismo , Fitocromo/metabolismo , Enfermedades de las Plantas/inmunología , Inmunidad de la Planta/efectos de la radiación , Solanum lycopersicum/inmunología , Susceptibilidad a Enfermedades , Luz , Solanum lycopersicum/microbiología , Solanum lycopersicum/efectos de la radiación , Enfermedades de las Plantas/microbiología
19.
Small ; 17(44): e2103406, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34561967

RESUMEN

The controlled assembly of nanowires is one of the key challenges in the development of a range of functional 3D aerogels with unique physicochemical properties for practical applications. However, the deep understanding of the dynamic assemble process for fabricating nanowire aerogels remains elusive. Herein, a facile strategy is presented for the metallic ion-induced assembly of nanowires into macroscopic aerogels via a solution-based process. This method enables the interconnecting between polymer-decorated nanowires via metallic coordination, resulting in plenty of nanowire bundles with the same orientation. Besides, the coordinated binding strength of nanowires with different metallic ions is also discussed. The assembly mechanism that the metallic ions induced dynamic behavior of nanowires is revealed via molecular dynamics theoretical evaluation. These findings benefit for constructing nanowire-based aerogels with unique structural features and multi-function, which pave new opportunities for other material systems.


Asunto(s)
Nanocables , Iones , Simulación de Dinámica Molecular , Polímeros
20.
Chemistry ; 27(2): 581-584, 2021 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-32865264

RESUMEN

An efficient direct aldol reaction between coumaran-3-ones and ß, γ-unsaturated α-ketoesters by virtue of a chiral copper complex is developed. A series of coumaran-3-one derivatives containing chiral tertiary alcohol structures are obtained in excellent yields and stereoselectivities.

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