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1.
Nature ; 575(7784): 639-642, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31776492

RESUMEN

Electrochemical carbon dioxide (CO2) reduction can in principle convert carbon emissions to fuels and value-added chemicals, such as hydrocarbons and alcohols, using renewable energy, but the efficiency of the process is limited by its sluggish kinetics1,2. Molecular catalysts have well defined active sites and accurately tailorable structures that allow mechanism-based performance optimization, and transition-metal complexes have been extensively explored in this regard. However, these catalysts generally lack the ability to promote CO2 reduction beyond the two-electron process to generate more valuable products1,3. Here we show that when immobilized on carbon nanotubes, cobalt phthalocyanine-used previously to reduce CO2 to primarily CO-catalyses the six-electron reduction of CO2 to methanol with appreciable activity and selectivity. We find that the conversion, which proceeds via a distinct domino process with CO as an intermediate, generates methanol with a Faradaic efficiency higher than 40 per cent and a partial current density greater than 10 milliamperes per square centimetre at -0.94 volts with respect to the reversible hydrogen electrode in a near-neutral electrolyte. The catalytic activity decreases over time owing to the detrimental reduction of the phthalocyanine ligand, which can be suppressed by appending electron-donating amino substituents to the phthalocyanine ring. The improved molecule-based electrocatalyst converts CO2 to methanol with considerable activity and selectivity and with stable performance over at least 12 hours.


Asunto(s)
Dióxido de Carbono , Electroquímica , Dióxido de Carbono/química , Catálisis , Indoles/química , Metanol/síntesis química , Nanotubos de Carbono/química , Compuestos Organometálicos/química
2.
Inorg Chem ; 2024 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-38941590

RESUMEN

Enantioselective synthesis of homochiral rare earth clusters is still a great challenge. In this work, we developed an efficient "cluster to cluster" approach, that is, a pair of enantiomerical R/S-{Nd8Fe3}-oxo clusters were successfully obtained from the presynthesized racemic {Nd9Fe2}-oxo cluster. R/S-hydrobenzoin ligands trigger the transformation of the pristine clusters by an SN2-like mechanism. Compared to the pristine cluster with an achiral core, the new cluster exhibits hierarchical chirality, from ligand chirality to interface chirality, then to helix chirality, and finally to supramolecular double helix chirality. The spectral experiments monitored the transformation and confirmed distinctly structure-related optical activity. The enantiomeric pure cluster also exhibits a potential asymmetric catalytic activity.

3.
Small ; 19(43): e2302768, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37381638

RESUMEN

The Li-CO2 battery has great potential for both CO2 utilization and energy storage, but its practical application is limited by low energy efficiency and short cycle life. Efficient cathode catalysts are needed to address this issue. Herein, this work reports on molecularly dispersed electrocatalysts (MDEs) of nickel phthalocyanine (NiPc) anchored on carbon nanotubes (CNTs) as the cathode catalyst for Li-CO2 batteries. The dispersed NiPc molecules efficiently catalyze CO2 reduction, while the conductive and porous CNTs networks facilitate CO2 evolution reaction, leading to enhanced discharging and charging performance compared to the NiPc and CNTs mixture. Octa-cyano substitution on NiPc (NiPc-CN) further enhances the interaction between the molecule and CNTs, resulting in better cycling stability. The Li-CO2 battery with the NiPc-CN MDE cathode shows a high discharge voltage of 2.72 V and a small discharging-charging potential gap of 1.4 V, and can work stably for over 120 cycles. The reversibility of the cathode is confirmed by experimental characterizations. This work lays a foundation for the development of molecular catalysts for Li-CO2 battery cathodes.

4.
Langmuir ; 39(20): 7184-7191, 2023 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-37167539

RESUMEN

Benefiting from the wide-range absorption and adjustable energy gap, carbon dots (C-dots) have attracted a great deal of attention and they have been used to sensitize semiconductor nanocomposites to boost the efficiency of energy conversion devices, while there is still a lack of fundamental understanding of the interaction between such materials and their influence on the catalytic activity on the reaction process. In this study, C-dots were used to modify TiO2 to form a direct Z-scheme (DZS) junction for enhancement of the photocatalytic activity. The C-dot/TiO2 composite was prepared by ultrasonication at room temperature through coupling between the Ti-O-C bond and electrostatic interaction. The C-dots can dramatically enhance the absorption of the composite by forming the DZS, and the composite is enabled to generate more free radicals, which facilitate ∼10 times higher photocatalytic activity compared to that of TiO2. As a proof of concept, the as-prepared C-dot/TiO2 was used for textile wastewater dye degradation. This study provides an efficient approach for room-temperature preparation of C-dot/TiO2 composites with high photocatalytic activity.

5.
Inorg Chem ; 62(46): 19153-19158, 2023 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-37934703

RESUMEN

The ability to conceptually mimic biomolecules to construct emergency-functional homospiral aggregates remains a long-standing challenge. Herein, we report artificial homohelical assembly by blending inorganic polyoxometalates (POMs) and organic cyclodextrin molecules. The chiral double-helical chains have been achieved by a left-hand arrangement of trimer-trimer. The trimer is formed by three {Mo8}@α-CD inclusive complexes as a Whittaker-style paddle wheel. During the process of assembly, chiral transfer and amplification from molecule to superstructure were observed. The enantioselective adsorption of the homohelical aggregate toward (R/S)-1,1'-binaphthyl-2,2'-diamine was further demonstrated. The interaction of {Mo8} and α-CD in solution was investigated. This work opens a wide scope for the design of a homohelix, enriching POM-based inorganic-organic materials.

6.
Inorg Chem ; 62(41): 16913-16918, 2023 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-37797212

RESUMEN

CdE (E = S, Se) quantum dots (QDs) with a broad and large Stokes shift PL emission have emerged as potential materials for white-light LEDs. However, this surface-related emission of nanocrystals is currently limited by low quantum efficiency. Herein, a convenient noninjected one-pot method at a relatively low temperature to prepare CdS QDs was readily achieved. The CdS-368 QD displays intense broad yellow emission in both solution and the solid state at room temperature. The coligation of organic and inorganic ligands passivates the electron trap states at the QD surface and suppresses nonradiative recombination, which is responsible for the high stability of colloids in organic solvents and the distinct fluorescence quantum yield.

7.
Neoplasma ; 69(6): 1437-1444, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36353935

RESUMEN

Pulmonary sarcomatoid carcinoma (PSC) is an aggressive and poorly differentiated type of non-small cell lung carcinoma. Because of the rarity of PSC, the efficacy and toxicity of immunotherapy remain unclear. Hence, the aim of this study was to evaluate the efficacy and safety of immune checkpoint inhibitors (ICIs) for the treatment of advanced PSC. The study cohort was limited to 33 patients with pathologically confirmed PSC treated with ICIs in four hospitals in China from March 2018 to March 2022. Expression of programmed death ligand 1 (PD-L1) was detected by immunohistochemical analysis. Categorical variables were compared with the Fisher exact test and survival analysis was conducted with the Kaplan-Meier method. Of the 33 PSC patients, 8 (24.2%) received monotherapy with ICIs and 25 (75.8%) received combination therapy with ICIs. The objective response rate (ORR) and disease control rate (DCR) were 36.4% and 78.8%, respectively. The median durations of progression-free survival (PFS) and overall survival (OS) were 6.07 and 21.33 months, respectively. PD-L1 status in 16 available samples was assessed, which included 30.3% PD-L1-positive patients. The ORRs for PD-L1-positive vs. -negative patients were 50.0% and 90.0%, the DCR was 33.3% and 83.3%, and the median PFS was 17.50 and 6.07 months, respectively (p=0.812). The median OS was not reached in PD-L1-positive and -negative patients (p=0.655). The incidence of immune-related adverse (irAEs) was 48.5% and mainly included grade 1 or 2 (39.4%), while the incidence of grade 3 or 4 was 9.1%. Pneumonia (9.1%) and skin rash (9.1%) were the most frequent irAEs. Immunotherapy with ICIs was a promising regimen to improve the prognosis of patients with advanced PSC.


Asunto(s)
Carcinoma , Neoplasias Pulmonares , Humanos , Neoplasias Pulmonares/patología , Pronóstico , Inhibidores de Puntos de Control Inmunológico/efectos adversos , Antígeno B7-H1 , Estudios Retrospectivos
8.
Plant Dis ; 2021 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-33970037

RESUMEN

Sarcandra glabra is an important Chinese medicinal plant, which was widely cultivated under forest in south China. Guangxi province is the main producing areas of this herb. In June 2019, a serious leaf disease was found causing severe defoliation in the S. glabra plantation under bamboo forest in Rongan country, Guangxi province (109°13'N''E). About 70% of the plants in the plantation (300 ha) showed the similar symptoms. Initially, circular lesions appeared on young leaves as black spots (about 1 to 2 mm). Then, the spots gradually enlarged usually with an obvious yellowish margin (6 to 8 mm). Finally, the lesions coalesced and formed irregular, black, and large necrotic areas, resulting in the leaf abscission. For pathogen isolation, small pieces of tissue (5×5 mm) taken from 25 diseased leaves were sterilized with 75% ethanol for 30 s, subsequently, soaked in 0.1% HgCl2 for 2 min, rinsed three times in sterile distilled water, dried, and then placed aseptically onto the potato dextrose agar (PDA) plates, and incubated at 28 °C (12 h/12 h light/dark). Three days later, the isolates were placed on a new PDA plate for subsequent purification and sporulation. 20 pure fungal isolates were obtained from single spores. Of which, 15 isolates showed similar morphological characteristics.The colonies on PDA were round, dense, gray edge and dark gray in center area. Conidia in culture were appeared light brown, cylindrical in shape, with 0 to 8 septa, and 55 to 165 µm × 5.2 to 13.5 µm in size (mean = 106.2 µm × 8.6 µm, n = 30). These morphological characteristics resemble those of Corynespora sp. (Berk. & M.A. Curtis) C.T. Wei (Ellis et al. 1971). A single-spore isolate (ZD5) was selected from the 15 fungal isolates for a subsequent molecular identification. The genes of internal transcribed spacer (ITS) of ribosomal DNA, ß-tublin, and actin were amplified with the primer pairs ITS-1/ITS-4 (White et al. 1990), ß-tubulin 2-Bt2a/Bt2b (Glass and Donaldson 1995), ACT-512F/ACT-783R (Carbone and Kohn 1999), respectively. And the ITS, ß-tublin, and actin sequences were deposited in the GenBank database with the accession numbers MW362446, MW367029, and MW533122. Blast analysis and neighbor-joining analysis based on ITS, ß-tublin, and actin sequences using MEGA 6 revealed that the isolate was placed in the same clade as C. cassicola with 100% bootstrap support. Pathogenicity test was performed on the two-year-old potted S. glabra. Six-mm-diameter mycelial plugs were attached to the healthy leaves of S. glabra for co-culture, while the control group was attached with PDA. All plants were covered with plastic bags for 2 days in order to maintain high humidity and cultured in a greenhouse at 28 °C with a 12-h/12-h light/dark cycle. The symptoms appeared 2 days after co-culture were identical to those observed in the field. The same fungus was re-isolated from the lesions, and further morphological characterization and molecular assays, as described above.The control leaves remained symptomless during the pathogenicity tests. According to the previous literatures, C. cassicola is a plant pathogenic fungus with a broad host range, which can damage diverse tropical plants including Salvia miltiorrhiza (Lu et al. 2019), Solanum americanum (Wagner and Louise 2019), Vitex rotundifolia (Yeh and Kirschner 2017), Cucumis sativus, Lycopersicon esculentum (Hsu et al. 2002), Carica papaya (Tsai et al. 2015),and so on. To our knowledge, this is the first report of C. cassicola causing leaf spot on S. glabra in China.

9.
Angew Chem Int Ed Engl ; 60(26): 14415-14419, 2021 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-33829603

RESUMEN

High-yield and large-scale synthesis are highly demanded for the studies of gold nanoclusters. We developed a "cluster from cluster" approach to assemble gold nanoclusters with preformed atomically precise Au13 precursors. This facile approach has proved to be very effective in the synthesis of the well-known magic cluster [Au25 (SR)18 ]- , which could prepare the target cluster in high yield (overall yield up to ≈100 %) at large scale (gram-scale based on gold). This method can be applied in the synthesis of 10 Au25 clusters with different R groups. This work presents an important approach that may be extended to high-yield and large-scale synthesis of other metal nanoclusters.

10.
J Mol Cell Cardiol ; 94: 122-130, 2016 05.
Artículo en Inglés | MEDLINE | ID: mdl-27066997

RESUMEN

AIMS: Increases in late Na(+) current (late INa) and activation of Ca(2+)/calmodulin-dependent protein kinase (CaMKII) are associated with atrial arrhythmias. CaMKII also phosphorylates Nav1.5, further increasing late INa. The combination of a CaMKII inhibitor with a late INa inhibitor may be superior to each compound alone to suppress atrial arrhythmias. Therefore, we investigated the effect of a CaMKII inhibitor in combination with a late INa inhibitor on anemone toxin II (ATX-II, a late INa enhancer)-induced atrial arrhythmias. METHODS AND RESULTS: Rat right atrial tissue was isolated and preincubated with either the CaMKII inhibitor autocamtide-2-related inhibitory peptide (AIP), the late INa inhibitor GS458967, or both, and then exposed to ATX-II. ATX-II increased diastolic tension and caused fibrillation of isolated right atrial tissue. AIP (0.3µmol/L) and 0.1µmol/L GS458967 alone inhibited ATX-II-induced arrhythmias by 20±3% (mean±SEM, n=14) and 34±5% (n=13), respectively, whereas the two compounds in combination inhibited arrhythmias by 81±4% (n=10, p<0.05, vs either AIP or GS458967 alone or the calculated sum of individual effects of both compounds). AIP and GS458967 also attenuated the ATX-induced increase of diastolic tension. Consistent with the mechanical and electrical data, 0.3µmol/L AIP and 0.1µmol/L GS458967 each inhibited ATX-II-induced CaMKII phosphorylation by 23±3% and 32±4%, whereas the combination of both compounds inhibited CaMKII phosphorylation completely. CONCLUSION: The effects of an enhanced late INa to induce arrhythmic activity and activation of CaMKII in atria are attenuated synergistically by inhibitors of late INa and CaMKII.


Asunto(s)
Potenciales de Acción , Ataxina-2/metabolismo , Fibrilación Atrial/etiología , Fibrilación Atrial/metabolismo , Proteína Quinasa Tipo 2 Dependiente de Calcio Calmodulina/metabolismo , Sodio/metabolismo , Animales , Bencilaminas/farmacología , Proteína Quinasa Tipo 2 Dependiente de Calcio Calmodulina/antagonistas & inhibidores , Atrios Cardíacos/efectos de los fármacos , Atrios Cardíacos/metabolismo , Masculino , Contracción Miocárdica/efectos de los fármacos , Ratas , Sulfonamidas/farmacología
11.
J Mol Cell Cardiol ; 76: 247-56, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25252177

RESUMEN

An increase of late Na(+) current (INaL) in cardiac myocytes can raise the cytosolic Na(+) concentration and is associated with activation of Ca(2+)/calmodulin-dependent protein kinase II (CaMKII) and alterations of mitochondrial metabolism and Ca(2+) handling by sarcoplasmic reticulum (SR). We tested the hypothesis that augmentation of INaL can increase mitochondrial reactive oxygen species (ROS) production and oxidation of CaMKII, resulting in spontaneous SR Ca(2+) release and increased diastolic Ca(2+) in myocytes. Increases of INaL and/or of the cytosolic Na(+) concentration led to mitochondrial ROS production and oxidation of CaMKII to cause dysregulation of Ca(2+) handling in rabbit cardiac myocytes.


Asunto(s)
Proteína Quinasa Tipo 2 Dependiente de Calcio Calmodulina/metabolismo , Miocitos Cardíacos/enzimología , Sodio/metabolismo , Potenciales de Acción , Animales , Señalización del Calcio , Femenino , Ventrículos Cardíacos/citología , Ventrículos Cardíacos/enzimología , Espacio Intracelular/metabolismo , Oxidación-Reducción , Estrés Oxidativo , Conejos , Especies Reactivas de Oxígeno/metabolismo
12.
Angew Chem Int Ed Engl ; 53(47): 12771-5, 2014 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-25160571

RESUMEN

A cluster-based luminescent porous metal-organic framework has been constructed through a "cluster linker" approach. The luminescent gold(I) cluster, prefunctionalized with pyrazinyl groups, was used as a cluster linker, similar to an organic linker, to connect silver ions in order to form a 3D framework. 1D channels with 1.1 nm diameter were observed in the framework. The cluster with its intrinsic luminescence was incorporated into a porous framework to give a luminescent bifunctional NbO net. This MOF shows solvatochromic behavior, and the interactions between solvent molecules and silver ions inside the channels account for the changes in absorption and emission spectra.


Asunto(s)
Oro/química , Luminiscencia , Compuestos Organometálicos/síntesis química , Plata/química , Estructura Molecular , Compuestos Organometálicos/química , Tamaño de la Partícula , Porosidad , Propiedades de Superficie
13.
Zhongguo Yi Liao Qi Xie Za Zhi ; 38(3): 181-5, 2014 May.
Artículo en Zh | MEDLINE | ID: mdl-25241511

RESUMEN

In this paper, according to the requirement of the focused sound field measurement, a focused sound field measurement system was established based on the LabVIEW virtual instrument platform. The system can automatically search the focus position of the sound field, and adjust the scanning path according to the size of the focal region. Three-dimensional sound field scanning time reduced from 888 hours in uniform step to 9.25 hours in variable step. The efficiency of the focused sound field measurement was improved. There is a certain deviation between measurement results and theoretical calculation results. Focal plane--6 dB width difference rate was 3.691%, the beam axis--6 dB length differences rate was 12.937%.


Asunto(s)
Análisis Numérico Asistido por Computador , Sonido , Simulación por Computador , Programas Informáticos
14.
Adv Sci (Weinh) ; 11(6): e2306190, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38049204

RESUMEN

Radiotherapy (RT) resistance is an enormous challenge in glioblastoma multiforme (GBM) treatment, which is largely associated with DNA repair, poor distribution of reactive radicals in tumors, and limited delivery of radiosensitizers to the tumor sites. Inspired by the aberrant upregulation of RAD51 (a critical protein of DNA repair), scavenger receptor B type 1 (SR-B1), and C-C motif chemokine ligand 5 (CCL5) in GBM patients, a reduction-sensitive nitric oxide (NO) donor conjugate of gemcitabine (RAD51 inhibitor) (NG) is synthesized as radio-sensitizer and a CCL5 peptide-modified bioinspired lipoprotein system of NG (C-LNG) is rationally designed, aiming to preferentially target the tumor sites and overcome the RT resistance. C-LNG can preferentially accumulate at the orthotopic GBM tumor sites with considerable intratumor permeation, responsively release the gemcitabine and NO, and then generate abundant peroxynitrite (ONOO- ) upon X-ray radiation, thereby producing a 99.64% inhibition of tumor growth and a 71.44% survival rate at 120 days in GL261-induced orthotopic GBM tumor model. Therefore, the rationally designed bioinspired lipoprotein of NG provides an essential strategy to target GBM and overcome RT resistance.


Asunto(s)
Glioblastoma , Oxadiazoles , Fármacos Sensibilizantes a Radiaciones , Humanos , Glioblastoma/tratamiento farmacológico , Glioblastoma/radioterapia , Glioblastoma/genética , Gemcitabina , Línea Celular Tumoral , Fármacos Sensibilizantes a Radiaciones/farmacología , Fármacos Sensibilizantes a Radiaciones/uso terapéutico , Lipoproteínas
15.
World J Gastrointest Oncol ; 16(1): 90-101, 2024 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-38292843

RESUMEN

BACKGROUND: Surgical resection remains the primary treatment for hepatic malignancies, and intraoperative bleeding is associated with a significantly increased risk of death. Therefore, accurate prediction of intraoperative bleeding risk in patients with hepatic malignancies is essential to preventing bleeding in advance and providing safer and more effective treatment. AIM: To develop a predictive model for intraoperative bleeding in primary hepatic malignancy patients for improving surgical planning and outcomes. METHODS: The retrospective analysis enrolled patients diagnosed with primary hepatic malignancies who underwent surgery at the Hepatobiliary Surgery Department of the Fourth Hospital of Hebei Medical University between 2010 and 2020. Logistic regression analysis was performed to identify potential risk factors for intraoperative bleeding. A prediction model was developed using Python programming language, and its accuracy was evaluated using receiver operating characteristic (ROC) curve analysis. RESULTS: Among 406 primary liver cancer patients, 16.0% (65/406) suffered massive intraoperative bleeding. Logistic regression analysis identified four variables as associated with intraoperative bleeding in these patients: ascites [odds ratio (OR): 22.839; P < 0.05], history of alcohol consumption (OR: 2.950; P < 0.015), TNM staging (OR: 2.441; P < 0.001), and albumin-bilirubin score (OR: 2.361; P < 0.001). These variables were used to construct the prediction model. The 406 patients were randomly assigned to a training set (70%) and a prediction set (30%). The area under the ROC curve values for the model's ability to predict intraoperative bleeding were 0.844 in the training set and 0.80 in the prediction set. CONCLUSION: The developed and validated model predicts significant intraoperative blood loss in primary hepatic malignancies using four preoperative clinical factors by considering four preoperative clinical factors: ascites, history of alcohol consumption, TNM staging, and albumin-bilirubin score. Consequently, this model holds promise for enhancing individualised surgical planning.

16.
Small Methods ; 7(1): e2201213, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36538738

RESUMEN

Single-atom catalysts (SACs) are of interest for chemical transformations of significant energy and environmental relevance because of the envisioned efficient use of active sites and the flexibility in tuning their coordination environment. Future advancement in this vein hinges upon the ability to further increase the number and accessibility of active sites in addition to fine-tuning their chemical environment. In this work, a Ni SAC is reported with a unique hierarchical hollow structure (Ni/HH) that allows increased accessibility of the active sites. The successful obtainment of such a uniquely structured catalyst was enabled by the judiciously chosen solvent mixtures for the preparation of the precursor whose hierarchical feature is maintained during the subsequent pyrolysis and etching of the pyrolysis product. Comparative catalytic and mechanistic studies with reference to three closely related but more compact Ni SACs established the superior performance of Ni/HH for selective electroreduction of CO2 to CO. Experimental analyses by in situ attenuated total reflection surface-enhanced infrared spectroscopy reveal that it is the facilitated formation of the *COOH intermediate in the rate-determining step that leads to the enhanced reaction kinetics and the overall catalytic performance.

17.
Polymers (Basel) ; 15(21)2023 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-37959915

RESUMEN

The catalytic conversion of cellulose to lactic acid (LA) has garnered significant attention in recent years due to the potential of cellulose as a renewable and sustainable biomass feedstock. Here, a series of Au/W-ZnO catalysts were synthesized and employed to transform cellulose into LA. Through the optimization of reaction parameters and catalyst compositions, we achieved complete cellulose conversion with a selectivity of 54.6% toward LA over Au/W-ZnO at 245 °C for 4 h. This catalyst system also proved effective at converting cotton and kenaf fibers. Structural and chemical characterizations revealed that the synergistic effect of W, ZnO, and Au facilitated mesoporous architecture generation and the establishment of an adequate acidic environment. The catalytic process proceeded through the hydrolysis of cellulose to glucose, isomerization to fructose, and its subsequent conversion to LA, with glucose isomerization identified as the rate-limiting step. These findings provide valuable insights for developing high-performance catalytic systems to convert cellulose.

18.
Int J Biol Macromol ; 253(Pt 8): 127601, 2023 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-37871718

RESUMEN

The objective of this research study is to develop novel composite nanofibers based on methacrylamide chitosan (ChMA)/poly(ε-caprolactone) (PCL) materials by the dual crosslinking and coaxial-electrospinning strategies. The prepared ChMA/PCL composite nanofibers can sequentially deliver tannic acid and curcumin drugs to synergistically inhibit bacterial reproduction and accelerate wound healing. The rapid delivery of tannic acid is expected to inhibit pathogenic microorganisms and accelerate epithelialization in the early stage, while the slow and sustained release of curcumin is with the aim of relieving chronic inflammatory response and inducing dermal tissue maturation in the late stage. Meanwhile, dual-drugs sequentially released from the membrane exhibited a DPPH free radical scavenging rate of ca. 95 % and an antibacterial rate of above 85 %. Moreover, the membrane possessed great biocompatibility in vitro and significantly inhibited the release of pro-inflammatory factors (IL-1ß and TNF-α) in vivo. Animal experiments showed that the composite membrane by means of the synergistic effect of polyphenol drugs and ChMA nanofibers, could significantly alleviate macrophage infiltration and accelerate the healing process of wounds. From the above, the as-prepared ChMA-based membrane with a stage-wise release pattern of drugs could be a promising bioengineered construct for wound healing application.


Asunto(s)
Quitosano , Curcumina , Nanofibras , Animales , Quitosano/química , Nanofibras/química , Curcumina/farmacología , Curcumina/química , Preparaciones Farmacéuticas , Cicatrización de Heridas , Poliésteres/química , Antibacterianos/farmacología
19.
Waste Manag ; 157: 159-167, 2023 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-36543059

RESUMEN

The demand for polypropylene (PP) melt-blown materials has dramatically increased due to the COVID-19 pandemic. It has caused serious environmental problems because of the lack of effective treatment for the waste PP melt-blown materials. In this study, we propose a green and sustainable recycling method to create PP sponges from waste PP melt-blown material for oil spill cleaning by freeze-drying and thermal treatment techniques. The recycling method is simple and without secondary pollution to the environment. The developed recycling method successfully transforms 2D laminar dispersed PP microfibers into elastic sponges with a 3D porous structure, providing the material with good mechanical properties and promotes its potential application in the field of oil spill cleaning. The morphology structure, thermal properties, mechanical properties, and oil absorption properties are tested and characterized. The PP sponges with a three-dimensional porous network structure show an exceedingly low density of >0.014 g/cm3, a high porosity of <98.77 %, and a high water contact angle range of 130.4-139.9°. Moreover, the PP sponges own a good absorption capacity of <47.61 g/g for different oil and solvents. In particular, the compressive modulus of the PP sponges is 33.59-201.21 kPa, which is higher than that of most other fiber-based porous materials, indicating that the PP sponges have better durability under the same force. The excellent comprehensive performance of the PP sponges demonstrates the method developed in this study has large application potential in the field of the recycle of waste PP melt-blown materials.


Asunto(s)
COVID-19 , Polipropilenos , Humanos , Polipropilenos/química , Pandemias , Residuos
20.
Front Endocrinol (Lausanne) ; 14: 1185799, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37351109

RESUMEN

Objective: Breast cancer is a prevalent malignancy that predominantly affects women. The development and progression of this disease are strongly influenced by the tumor microenvironment and immune infiltration. Therefore, investigating immune-related genes associated with breast cancer prognosis is a crucial approach to enhance the diagnosis and treatment of breast cancer. Methods: We analyzed data from the TCGA database to determine the proportion of invasive immune cells, immune components, and matrix components in breast cancer patients. Using this data, we constructed a risk prediction model to predict breast cancer prognosis and evaluated the correlation between KLRB1 expression and clinicopathological features and immune invasion. Additionally, we investigated the role of KLRB1 in breast cancer using various experimental techniques including real-time quantitative PCR, MTT assays, Transwell assays, Wound healing assays, EdU assays, and flow cytometry. Results: The functional enrichment analysis of immune and stromal components in breast cancer revealed that T cell activation, differentiation, and regulation, as well as lymphocyte differentiation and regulation, play critical roles in determining the status of the tumor microenvironment. These DEGs are therefore considered key factors affecting TME status. Additionally, immune-related gene risk models were constructed and found to be effective predictors of breast cancer prognosis. Further analysis through KM survival analysis and univariate and multivariate Cox regression analysis demonstrated that KLRB1 is an independent prognostic factor for breast cancer. KLRB1 is closely associated with immunoinfiltrating cells. Finally, in vitro experiments confirmed that overexpression of KLRB1 inhibits breast cancer cell proliferation, migration, invasion, and DNA replication ability. KLRB1 was also found to inhibit the proliferation of breast cancer cells by blocking cell division in the G1/M phase. Conclusion: KLRB1 may be a potential prognostic marker and therapeutic target associated with the microenzymic environment of breast cancer tumors, providing a new direction for breast cancer treatment.


Asunto(s)
Neoplasias de la Mama , Humanos , Femenino , Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/genética , Pronóstico , Diferenciación Celular , Bioensayo , Bases de Datos Factuales , Microambiente Tumoral/genética , Subfamilia B de Receptores Similares a Lectina de Células NK
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