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1.
Heliyon ; 10(10): e31365, 2024 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-38818193

RESUMEN

Goupi plaster, a representative preparation of black plaster, has demonstrated promising effects in treating knee osteoarthritis. However, high temperature used in traditional frying extraction may cause decomposition of its effective components, thus limiting the efficacy. This study aimed to explore the scientific nature of the traditional preparation technology of Goupi plaster, and to compare the effects of different extraction methods on the types of chemical components and the content of index components. The UPLC-Q-Exactive-MS and UPLC-MS/MS technologies which have high efficiency, sensitivity and accuracy, were used to qualitatively and quantitatively analyze the chemical components of Goupi plaster under different preparation processes. The results show that the extraction solvent approach is different from the traditional frying extraction method, and has a positive effect. However, the mechanism of action of Goupi plaster is complex and its pharmacological effects are diverse. Future studies should explore whether it necessary to change the frying extraction method. This experiment provides a theoretical basis that will guide further scientific discussion and research into the frying extraction of Goupi plaster.

2.
Angew Chem Int Ed Engl ; 63(17): e202400142, 2024 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-38421200

RESUMEN

Our society has been pursuing high-performance biodegradable polymers made from facile methods and readily available monomers. Here, we demonstrate a library of enzyme-degradable polymers with desirable properties from the first reported step polyaddition of diamines, COS, and diacrylates. The polymers contain in-chain ester and thiourethane groups, which can serve as lipase-degradation and hydrogen-bonding physical crosslinking points, respectively, resulting in possible biodegradability as well as upgraded mechanical and thermal properties. Also, the properties of the polymers are scalable due to the versatile method and the wide variety of monomers. We obtain 46 polymers with tunable performance covering high-Tm crystalline plastics, thermoplastic elastomers, and amorphous plastics by regulating polymer structure. Additionally, the polymerization method is highly efficient, atom-economical, quantitatively yield, metal- and even catalyst-free. Overall, the polymers are promising green materials given their degradability, simple and modular synthesis, remarkable and tunable properties, and readily available monomers.

3.
Small Methods ; 8(2): e2300432, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37530212

RESUMEN

Tandem solar cells are rationally designed and fabricated by stacking multiple subcells to achieve power conversion efficiency well above the Shockley-Queisser (SQ) limit. There is a large selection pool for the subcell candidates, such as Si, III-V, Kesterite, Perovskite, and organic solar cells. A series of different combinations of these subcells have been successfully demonstrated in practical tandem solar cell devices. However, there has not been a systematic summary of how to connect subcells in a tandem solar cell using a practical, cost-effective, and efficiency-beneficial fashion. In this work, the connection manners of subcells within a tandem cell are classified into three main categories, performing sequential growth, using the physical connection, and applying an intermediate layer, focusing on systematical description of intermediate layers using different materials. The advantages and disadvantages of these connection methods and their applicability to tandem cell types are further elaborated using two typical example models, III-V/Si and Perovskite inclusive tandem cell devices. Eventually, this work can provide useful guidance on how to carry out a suitable intermediate connection in the design of tandem solar cells depending on the selected subcells and device structure.

4.
Math Biosci Eng ; 20(9): 16212-16235, 2023 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-37920010

RESUMEN

Third-party logistics companies face a challenging task in minimizing inventory transportation costs due to the complexities of managing numerous suppliers. Effectively optimizing costs becomes a formidable problem for such companies. This empirical research has yielded strategies for minimizing the inventory transportation cost specifically for company D. Through a rigorous optimization process, the findings presented in this paper demonstrate an average reduction of 7.18% in company D's inventory transportation cost. By jointly optimizing inbound logistics inventory transportation under VMI-TPL mode, this study extends the theory of supplier managed inventory and improves the inbound logistics mode. The results of this study can provide quantitative support and decision-making references for the project operation management of company D and similar enterprises.

5.
BMC Biol ; 21(1): 160, 2023 07 19.
Artículo en Inglés | MEDLINE | ID: mdl-37468903

RESUMEN

BACKGROUND: Conversion or editing of adenosine (A) into inosine (I) catalyzed by specialized cellular enzymes represents one of the most common post-transcriptional RNA modifications with emerging connection to disease. A-to-I conversions can happen at specific sites and lead to increase in proteome diversity and changes in RNA stability, splicing, and regulation. Such sites can be detected as adenine-to-guanine sequence changes by next-generation RNA sequencing which resulted in millions reported sites from multiple genome-wide surveys. Nonetheless, the lack of extensive independent validation in such endeavors, which is critical considering the relatively high error rate of next-generation sequencing, leads to lingering questions about the validity of the current compendiums of the editing sites and conclusions based on them. RESULTS: Strikingly, we found that the current analytical methods suffer from very high false positive rates and that a significant fraction of sites in the public databases cannot be validated. In this work, we present potential solutions to these problems and provide a comprehensive and extensively validated list of A-to-I editing sites in a human cancer cell line. Our findings demonstrate that most of true A-to-I editing sites in a human cancer cell line are located in the non-coding transcripts, the so-called RNA 'dark matter'. On the other hand, many ADAR editing events occurring in exons of human protein-coding mRNAs, including those that can recode the transcriptome, represent false positives and need to be interpreted with caution. Nonetheless, yet undiscovered authentic ADAR sites that increase the diversity of human proteome exist and warrant further identification. CONCLUSIONS: Accurate identification of human ADAR sites remains a challenging problem, particularly for the sites in exons of protein-coding mRNAs. As a result, genome-wide surveys of ADAR editome must still be accompanied by extensive Sanger validation efforts. However, given the vast number of unknown human ADAR sites, there is a need for further developments of the analytical techniques, potentially those that are based on deep learning solutions, in order to provide a quick and reliable identification of the editome in any sample.


Asunto(s)
Proteoma , Edición de ARN , Humanos , Proteoma/genética , ARN/metabolismo , ARN Mensajero/metabolismo , Línea Celular , Adenosina Desaminasa/genética , Adenosina Desaminasa/metabolismo
6.
Adv Mater ; 35(42): e2303936, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37453141

RESUMEN

Thin-film solar cells are expected to play a significant role in the space industry, building integrated photovoltaic (BIPV), indoor applications, and tandem solar cells, where bifaciality and semitransparency are highly desired. Sb2 (S,Se)3 has emerged as a promising new photovoltaic (PV) material for its high absorption coefficient, tunable bandgap, and nontoxic and earth-abundant constituents. However, high-efficiency Sb2 (S,Se)3 solar cells exclusively employ monofacial architectures, leaving a considerable gap toward large-scale application in aforementioned fields. Here, a bifacial and semitransparent Sb2 (S,Se)3 solar cell and its extended application in tandem solar cells are reported. The transparent conductive oxides (TCOs) and the ultrathin inner n-i-p structure provide high long-wavelength transmittance. Despite the MnS/ITO Schottky junction, power conversion efficiencies (PCEs) of 7.41% and 6.36% are achieved with front and rear illumination, respectively, contributing to a great bifaciality of 0.86. Consequently, the reported device gains great enhancement in PV performance by exploiting albedo of surroundings and shows exceptional capability in absorbing tilt incident light. Moreover, an Sb2 (S,Se)3 /Si tandem solar cell with a PCE of 11.66% is achieved in preliminary trials. These exciting findings imply that bifacial and semitransparent Sb2 (S,Se)3 solar cells possess tremendous potential in practical applications based on their unique characteristics.

7.
Angew Chem Int Ed Engl ; 62(37): e202306731, 2023 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-37490022

RESUMEN

The facile synthesis of chemically recyclable polymers derived from sustainable feedstocks presents enormous challenges. Here, we develop a novel, modular, and efficient click reaction for connecting primary, secondary, or tertiary alcohols with activated alkenes via a bridge molecule of carbonyl sulfide (COS). The click reaction is successfully applied to synthesize a series of recyclable polymers by the step polyaddition of diols, diacrylates, and COS. Diols and diacrylates are common chemicals and can be produced from biorenewable sources, and COS is released as the industrial waste. In addition to sustainable monomers, the approach is atom-economical, wide in scope, metal-free, and performed under mild conditions, affording unprecedented polymers with nearly quantitative yields. The produced polymers also possess predesigned and widely tunable structure owing to the versatility of our method and the broad variety of monomers. The in-chain thiocarbonate and ester polar groups can play as breakpoints, allowing these polymers to be easily recycled. Overall, the polymers have broad prospects for green materials given their facile synthesis, readily available feedstocks, desirable performance, and chemical recyclability.

8.
ACS Omega ; 7(10): 8717-8723, 2022 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-35309440

RESUMEN

Copyrolysis of coal and biomass has been extensively studied to exploit its inherent synergistic effects; however, the different pyrolysis temperature zones of coal and biomass seriously affect the realization of these effects. Therefore, a new copyrolysis method (preheating the coal to a certain temperature and then adding the biomass in a drop-tube-fixed-bed reactor, denoted as M1) was designed herein to achieve "simultaneous" pyrolysis of coal and biomass. The yields of products and the characteristics of M1-produced tar were estimated and compared with those of tar obtained by fixed-bed-reactor (denoted as M2)-based copyrolysis. M1 achieved a higher tar yield and lower water content than M2. The M1-generated tar exhibited a lower free-radical concentration, higher H/C ratio, higher levels of uncondensed aromatic hydrogen, and shorter side-chains than that produced by M2. The temperature of HLBE coal at which the WSs were fed to the reactor in M1, denoted as T F, affects the "simultaneous" pyrolysis. T F values of 300, 400, and 500 °C were studied, and it was found that the tar yield obtained at a T F of 400 °C (the main pyrolysis temperature of coal) is the highest, the water yield is the lowest, and the free-radical concentration of the tar is also the lowest among the investigated samples.

9.
ACS Omega ; 6(46): 31058-31065, 2021 Nov 23.
Artículo en Inglés | MEDLINE | ID: mdl-34841148

RESUMEN

In this study, variations in the free radical concentration, degree of swelling (Q), and extraction yield of Buertai coal (C%, 80.4%) in 11 solvents with different characteristics were determined to investigate the interaction between the coal and solvent, as well as the bond cleavage during solvent extraction. Derivative thermogravimetry (DTG) results for the residues and raw coal were compared to confirm whether the covalent bond breaks during solvent extraction. The free radical concentration decreases in certain solvents but increases in a few others. The relative free radical concentration, Q, and extraction yield are positively correlated. The charge-transfer capability of the solvent, and in particular its electron-donating capability, plays an essential role in influencing the interaction between the coal and solvent. The increase in the free radical concentration during solvent extraction can be attributed to (1) the formation or decomposition of charge-transfer complexes, (2) dissociation of charge-transfer complexes into radical ions, and (3) breakage of weak covalent bonds. DTG results show the occurrence of weak covalent bonds breakage at temperatures of 133.9-320.1 °C during solvent extraction due to the reduction of the bond energy caused by the formation of radical ions.

10.
Nat Commun ; 11(1): 2266, 2020 05 08.
Artículo en Inglés | MEDLINE | ID: mdl-32385244

RESUMEN

The evolutionarily conserved Par3/Par6/aPKC complex regulates the polarity establishment of diverse cell types and distinct polarity-driven functions. However, how the Par complex is concentrated beneath the membrane to initiate cell polarization remains unclear. Here we show that the Par complex exhibits cell cycle-dependent condensation in Drosophila neuroblasts, driven by liquid-liquid phase separation. The open conformation of Par3 undergoes autonomous phase separation likely due to its NTD-mediated oligomerization. Par6, via C-terminal tail binding to Par3 PDZ3, can be enriched to Par3 condensates and in return dramatically promote Par3 phase separation. aPKC can also be concentrated to the Par3N/Par6 condensates as a client. Interestingly, activated aPKC can disperse the Par3/Par6 condensates via phosphorylation of Par3. Perturbations of Par3/Par6 phase separation impair the establishment of apical-basal polarity during neuroblast asymmetric divisions and lead to defective lineage development. We propose that phase separation may be a common mechanism for localized cortical condensation of cell polarity complexes.


Asunto(s)
Proteínas de Drosophila/metabolismo , Drosophila melanogaster/metabolismo , Complejos Multiproteicos/metabolismo , Animales , Células COS , Ciclo Celular , Diferenciación Celular , Supervivencia Celular , Chlorocebus aethiops , Proteínas de Drosophila/química , Drosophila melanogaster/citología , Proteínas Fluorescentes Verdes/metabolismo , Células HEK293 , Humanos , Larva/citología , Complejos Multiproteicos/química , Neuronas/citología , Neuronas/metabolismo , Dominios Proteicos , Proteína Quinasa C/metabolismo , Ratas
11.
Sci Rep ; 10(1): 5384, 2020 03 25.
Artículo en Inglés | MEDLINE | ID: mdl-32214175

RESUMEN

Over the past two decades, many studies have shown that the yam storage protein dioscorin, which is abundant in the wastewater of starch processing, exhibits many biological activities both in vitro and in vivo. In the present study, the acid-precipitation method was optimized using Box-Behnken design (BBD) combined with response surface methodology (RSM) for the recovery of yam soluble protein (YSP) from wastewater. The experimental yield of YSP reached 57.7%. According to relative quantitative proteomics (LC-MS/MS), the crude YSP was mainly composed of 15 dioscorin isoforms, which was further verified by anion-exchange and size-exclusion chromatography. YSP was found to be rich in glutamic acid and aspartic acid, and the eight essential acids made up approximately 33.7% of the YSP. Moreover, the YSP demonstrated antioxidant activity, including scavenging DPPH, hydroxyl and superoxide anion radicals, and the possible structure-activity relationships were discussed. These results indicated that YSP produced by acid precipitation may be used as a protein source with antioxidant properties.


Asunto(s)
Dioscorea/química , Dioscorea/metabolismo , Proteínas de Plantas/aislamiento & purificación , Cromatografía Liquida/métodos , Concentración de Iones de Hidrógeno , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Espectrometría de Masas en Tándem/métodos , Aguas Residuales/análisis , Aguas Residuales/química
12.
Food Res Int ; 126: 108617, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31732068

RESUMEN

Proteins were extracted from Se-enriched peanut leaves, an agro-byproduct, and the foliar application of sodium selenite was indicated to be an effective method to incorporate Se into leaf selenoproteins with 75-80% incorporation rates. After trypsin digestion, the most abundant proteins from Se-enriched peanut leaf (PSPL) were identified as pathogenesis-related class 10 proteins, Ara h 8 allergen and its isoforms, using LC-MS/MS. The Se species in both the low Se PSPL and high Se PSPL were determined to be selenomethionine (SeMet), methylselenocysteine (MeSeCys) and selenocystine (SeCys2) with SeMet (15.6 mg/g) dominated the high Se PSPL. Their antioxidant activities were also evaluated using free radical scavenging assay, reducing power assay and ferric thiocyanate (FTC) test. As results, the PSPL exhibited potent DPPH radical (96.2%) and superoxide anion radical (98.4%) scavenging activities and showed strong reducing power in a Se-concentration-dependent manner, indicating that PSPL can be used as antioxidants and Se sources to improve health.


Asunto(s)
Antioxidantes/análisis , Arachis , Hojas de la Planta/química , Proteínas de Plantas/química , Selenio/análisis , Selenito de Sodio/administración & dosificación , Alimentación Animal/análisis , Alimentos Fortificados/análisis , Depuradores de Radicales Libres/análisis , Oxidación-Reducción , Selenoproteínas/análisis , Superóxidos/química
13.
Nat Commun ; 10(1): 3162, 2019 07 18.
Artículo en Inglés | MEDLINE | ID: mdl-31320636

RESUMEN

HECT E3 ligases control the degradation and functioning of numerous oncogenic/tumor-suppressive factors and signaling proteins, and their activities must be tightly regulated to prevent cancers and other diseases. Here we show that the Nedd4 family HECT E3 WWP1 adopts an autoinhibited state, in which its multiple WW domains sequester HECT using a multi-lock mechanism. Removing WW2 or WW34 led to a partial activation of WWP1. The structure of fully inhibited WWP1 reveals that many WWP1 mutations identified in cancer patients result in a partially active state with increased E3 ligase activity, and the WWP1 mutants likely promote cell migration by enhancement of ∆Np63α degradation. We further demonstrate that WWP2 and Itch utilize a highly similar multi-lock autoinhibition mechanism as that utilized by WWP1, whereas Nedd4/4 L and Smurf2 utilize a slightly variant version. Overall, these results reveal versatile autoinhibitory mechanisms that fine-tune the ligase activities of the HECT family enzymes.


Asunto(s)
Ubiquitina-Proteína Ligasas Nedd4/metabolismo , Ubiquitina-Proteína Ligasas/genética , Ubiquitina-Proteína Ligasas/metabolismo , Línea Celular Tumoral , Movimiento Celular/genética , Cristalografía por Rayos X , Activación Enzimática , Células HEK293 , Humanos , Ubiquitina-Proteína Ligasas Nedd4/genética , Dominios Proteicos , Proteínas Represoras/metabolismo , Factores de Transcripción/metabolismo , Proteínas Supresoras de Tumor/metabolismo
14.
Nat Commun ; 9(1): 737, 2018 02 21.
Artículo en Inglés | MEDLINE | ID: mdl-29467404

RESUMEN

Uneven distribution and local concentration of protein complexes on distinct membrane cortices is a fundamental property in numerous biological processes, including Drosophila neuroblast (NB) asymmetric cell divisions and cell polarity in general. In NBs, the cell fate determinant Numb forms a basal crescent together with Pon and is segregated into the basal daughter cell to initiate its differentiation. Here we discover that Numb PTB domain, using two distinct binding surfaces, recognizes repeating motifs within Pon in a previously unrecognized mode. The multivalent Numb-Pon interaction leads to high binding specificity and liquid-liquid phase separation of the complex. Perturbations of the Numb/Pon complex phase transition impair the basal localization of Numb and its subsequent suppression of Notch signaling during NB asymmetric divisions. Such phase-transition-mediated protein condensations on distinct membrane cortices may be a general mechanism for various cell polarity regulatory complexes.


Asunto(s)
División Celular Asimétrica , Proteínas Portadoras/fisiología , Proteínas de Drosophila/fisiología , Drosophila melanogaster/embriología , Hormonas Juveniles/fisiología , Neurogénesis , Neuronas/metabolismo , Secuencias de Aminoácidos , Animales , Diferenciación Celular , Membrana Celular/metabolismo , Polaridad Celular , Regulación del Desarrollo de la Expresión Génica , Células HEK293 , Células HeLa , Humanos , Unión Proteica , Dominios Proteicos , Transducción de Señal
15.
J Biol Chem ; 293(11): 4149-4158, 2018 03 16.
Artículo en Inglés | MEDLINE | ID: mdl-29382713

RESUMEN

Traffic of cargo across membranes helps establish, maintain, and reorganize distinct cellular compartments and is fundamental to many metabolic processes. The cargo-selective endocytic adaptor Numb participates in clathrin-dependent endocytosis by attaching cargoes to the clathrin adaptor α-adaptin. The phosphorylation of Numb at Ser265 and Ser284 recruits the regulatory protein 14-3-3, accompanied by the dissociation of Numb from α-adaptin and Numb's translocation from the cortical membrane to the cytosol. However, the molecular mechanisms underlying the Numb-α-adaptin interaction and its regulation by Numb phosphorylation and 14-3-3 recruitment remain poorly understood. Here, biochemical and structural analyses of the Numb·14-3-3 complex revealed that Numb phosphorylation at both Ser265 and Ser284 is required for Numb's efficient interaction with 14-3-3. We also discovered that an RQFRF motif surrounding Ser265 in Numb functions together with the canonical C-terminal DPF motif, required for Numb's interaction with α-adaptin, to form a stable complex with α-adaptin. Of note, we provide evidence that the phosphorylation-induced binding of 14-3-3 to Numb directly competes with the binding of α-adaptin to Numb. Our findings suggest a potential mechanism governing the dynamic assembly of Numb with α-adaptin or 14-3-3. This dual-site recognition of Numb by α-adaptin may have implications for other α-adaptin targets. We propose that the newly identified α-adaptin-binding site surrounding Ser265 in Numb functions as a triggering mechanism for the dynamic dissociation of the Numb·α-adaptin complex.


Asunto(s)
Proteínas 14-3-3/metabolismo , Subunidades alfa de Complejo de Proteína Adaptadora/metabolismo , Endocitosis/fisiología , Proteínas de la Membrana/química , Proteínas de la Membrana/metabolismo , Proteínas del Tejido Nervioso/química , Proteínas del Tejido Nervioso/metabolismo , Proteínas 14-3-3/química , Subunidades alfa de Complejo de Proteína Adaptadora/química , Animales , Sitios de Unión , Catálisis , Dominio Catalítico , Cristalografía por Rayos X , Ratones , Modelos Moleculares , Fosforilación , Unión Proteica , Conformación Proteica , Relación Estructura-Actividad
16.
Yao Xue Xue Bao ; 48(11): 1665-70, 2013 Nov.
Artículo en Chino | MEDLINE | ID: mdl-24475703

RESUMEN

SHG was sulfated by chlorosulfonic acid-pyridine method, and six samples which we got were prepared in different reaction conditions. There is a characteristic absorption peak near 260 nm in UV spectra and there are two characteristic absorption peaks near 1240 cm(-1) and 810 cm(-1) in the FT-IR. Degree of sulfation (DS) was calculated by elemental analysis and turbidimetry. Under the same conditions the absorption peaks become strong with the DS increase. The anticoagulant activity of SHG and sulfated modification samples was evaluated by the classic coagulant assays of prothrombin time (PT), activated partial thrombin time (APTT) live enzymes, and plasma thrombin time (TT). Results show that sulfated SHG has a good anticoagulant activity in vitro, and DS increased activity within a certain range.


Asunto(s)
Anticoagulantes/farmacología , Fabaceae/química , Glucanos/farmacología , Animales , Anticoagulantes/química , Anticoagulantes/aislamiento & purificación , Pruebas de Coagulación Sanguínea , Glucanos/química , Glucanos/aislamiento & purificación , Tiempo de Tromboplastina Parcial , Plantas Medicinales/química , Tiempo de Protrombina , Conejos , Espectrofotometría Ultravioleta , Espectroscopía Infrarroja por Transformada de Fourier , Ácidos Sulfónicos/química , Tiempo de Trombina
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