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1.
Langmuir ; 40(22): 11684-11694, 2024 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-38781129

RESUMEN

The exceptional hydrophobicity and antifouling properties of polydimethylsiloxane (PDMS) composites have attracted extensive interest as a result of low surface energy. However, PDMS composites are hardly bound by common primers, greatly limiting their practical applications. To address this issue, an EPMS/VTMS (EV) primer synthesized by hydrolytic polycondensation of 3-[(2,3)-epoxypropoxypropyl]methyldiethoxysilane (EPMS) and vinyltrimethoxysilane (VTMS) in acidic conditions is proposed. Interestingly, the EV primer exhibits exceptional reactivity, self-healing capabilities, and strong adhesion to various substrates, including metals, plastics, and glass. The bonding aluminum plates are easily debonded by immersion in water without any residue left. Subsequently, the EV primer has been applied to the interface between silicone leather and the PDMS composite. Results show that the bonding strength for the silicone leather coated with the EV/PDMS composite is 16 times higher than that of the silicone leather modified with the PDMS composite. Meanwhile, the modified silicone leather exhibits impressive antifouling performance, including aqueous and oily stains, appreciable breathability, and excellent wear resistance, even if suffering from 20 000 cycles of abrasion. These excellent advantages for the modified silicone leather should be attributable to the synergistic effect of the EV primer and the PDMS composite. These findings pave the way to develop an ecofriendly debonding primer for PDMS composites, greatly facilitating applications of silicone leather.

2.
BMC Psychiatry ; 24(1): 192, 2024 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-38454373

RESUMEN

BACKGROUND: In China, about 18.70% of the population aged 60 years and older are at risk of low personal mastery as well as anxiety and depression for a variety of reasons. The purpose of this study was to construct a symptom network model of the relationship between anxiety, depression, and personal mastery in community-dwelling older adults and to identify central and bridge symptoms in this network. METHODS: Depression, anxiety, and personal mastery were measured using the Patient Health Questionnaire-9 (PHQ-9), Generalized Anxiety Disorder Scale (GAD-7), and Personal Mastery Scale (PMS), respectively. A total of 501 older adults in 16 communities in Changzhou and Zhenjiang, Jiangsu Province, China, were surveyed by using a combination of stratified sampling and convenience sampling methods. The R language was used to construct the network. RESULTS: (1) The network structure of anxiety-depression-personal mastery was stable, with "Nervousness" (node GAD1, strength = 1.38), "Sad mood" (node PHQ2, strength = 1.22), " Inability to change" (node PMS2, strength = 1.01) and "Involuntarily" (node PMS3, strength = 0.95) as the central symptoms. (2) "Irritability" (node GAD6, bridge strength = 0.743), "Sad mood" (node PHQ2, bridge strength = 0.655), and "Trouble relaxing" (node GAD4, bridge strength = 0.550) were the bridge symptoms connecting anxiety, depressive symptoms, and personal mastery. (3) In the network comparison test (NCT), residence, somatic chronic comorbidity and gender had no significant effect on network structure. CONCLUSIONS: The construction of the anxiety-depression-personal mastery network structure opens up new possibilities for mechanisms of action and intervention formulation for psychological disorders in community-dwelling older adults. The identification of central symptoms (e.g., nervousness, sad mood, inability to change, involuntarily) and bridge symptoms (e.g., irritability, sad mood, trouble relaxing) in community-dwelling older adults with anxiety, depression, and low sense of mastery can provide a scientific basis for the development of precise interventions.


Asunto(s)
Depresión , Vida Independiente , Humanos , Persona de Mediana Edad , Anciano , Depresión/psicología , Ansiedad/psicología , Trastornos de Ansiedad/diagnóstico , Trastornos de Ansiedad/epidemiología , Comorbilidad
3.
Chemistry ; 29(25): e202202918, 2023 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-36637457

RESUMEN

A series of transition metal (M)-promoted carbon-silicon (C-M-Si; M=Mn, Fe, Co, Ni, Cu, Zn, Zr) solid acid catalysts with designated molar ratio of M/Si=1 : 8 were fabricated and exploited for acetalization of benzaldehyde (BzH) with ethylene glycol (EG). The physical and chemical properties of these C-M-Si catalysts prepared by sol-gel method were characterized by various techniques, namely, SEM, EDS, TGA-DTG, BET, XRD, FTIR, XPS, and NH3 -TPD. Among various examined acidic C-M-Si catalysts, the C-Fe-Si catalyst exhibited the optimal catalytic activity with the benzaldehyde glycol acetal (BEGA) yield of 97.67 %, in excellent agreement with the value (97.88 %) predicted by the response surface methodology (RSM) based on a Box-Behnken design (BBD). C-Fe-Si catalyst with the high catalytic activities and excellent stability and reusability may be ascribed to the suitable acidity and uniform surface distribution of active sites requisite for the acid-catalyzed acetalization reaction.

4.
Support Care Cancer ; 32(1): 62, 2023 Dec 27.
Artículo en Inglés | MEDLINE | ID: mdl-38150034

RESUMEN

BACKGROUND: Colorectal cancer incidence is on the rise, necessitating precise symptom management. However, causal relationships among symptoms have been challenging to establish due to reliance on cross-sectional data. Cross-lagged panel network (CLPN) analysis offers a solution, leveraging longitudinal data for insight. OBJECTIVE: We employed CLPN analysis to construct symptom networks in colorectal cancer patients at three perioperative time points, aiming to identify predictive relationships and intervention opportunities. METHODS: We evaluated the prevalence and severity of symptoms throughout the perioperative period, encompassing T1 the first day of admission, T2 2-3 days postoperatively, and T3 discharge, utilizing the M. D. Anderson Symptom Inventory Gastrointestinal Cancer Module (MDASI-GI). To identify crucial nodes in the network and explore predictive and interactive effects among symptoms, CLPNs were constructed from longitudinal data in R. RESULTS: The analysis revealed a stable network, with disturbed sleep exhibiting the highest out-EI (outgoing expected influence) during T1. Distress had a sustained impact throughout the perioperative. Disturbed sleep at T1 predicted T2 bloating, fatigue, distress, and pain. T1 distress predicted T2 sadness severity. T2 distress primarily predicted T3 fatigue, disturbed sleep, changes in taste, and bloating. T2 shortness of breath predicted T3 changes in taste and loss of appetite. Furthermore, biochemical markers like RBC and ALB had notable influence on symptom clusters during T1→T2 and T2→T3, respectively. CONCLUSION: Prioritizing disturbed sleep during T1 and addressing distress throughout the perioperative phase is recommended. Effective symptom management not only breaks the chain of symptom progression, enhancing healthcare impact, but also eases patient symptom burdens.


Asunto(s)
Neoplasias Colorrectales , Humanos , Apetito , Neoplasias Colorrectales/complicaciones , Neoplasias Colorrectales/cirugía , Estudios Transversales , Disnea/epidemiología , Fatiga/epidemiología , Sueño
5.
Int J Mol Sci ; 24(5)2023 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-36902465

RESUMEN

Reinforcement of polymer nanocomposites can be achieved by the selection of the appropriate fabrication method, surface modification, and orientation of the filler. Herein, we present a nonsolvent-induced phase separation method with ternary solvents to prepare thermoplastic polyurethane (TPU) composite films with excellent mechanical properties using 3-Glycidyloxypropyltrimethoxysilane-modified cellulose nanocrystals (GLCNCs). ATR-IR and SEM analyses of the GLCNCs confirmed that GL was successfully coated on the surface of the nanocrystals. The incorporation of GLCNCs in TPU resulted in the enhancement of the tensile strain and toughness of pure TPU owing to the enhanced interfacial interactions between them. The GLCNC-TPU composite film had tensile strain and toughness values of 1740.42% and 90.01 MJ/m3, respectively. Additionally, GLCNC-TPU exhibited a good elastic recovery rate. CNCs were readily aligned along the fiber axis after the spinning and drawing of the composites into fibers, which further improved the mechanical properties of the composites. The stress, strain, and toughness of the GLCNC-TPU composite fiber increased by 72.60%, 10.25%, and 103.61%, respectively, compared to those of the pure TPU film. This study demonstrates a facile and effective strategy for fabricating mechanically enhanced TPU composites.


Asunto(s)
Nanopartículas , Poliuretanos , Poliuretanos/química , Silanos , Celulosa/química , Polímeros/química , Nanopartículas/química
6.
Small ; 18(5): e2105198, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34825459

RESUMEN

Structural design of the solar-absorbing layer has been considered as one of the most direct and effective approaches for improving the solar steam generation performance by maximizing the absorption of sunlight, but great challenges in manipulation simplification and structure controllability still remain. Herein, a polyester (PET) fabric covered with a vertically aligned 3D tower-like ferrosoferric oxide (Fe3 O4 ) array via a convenient magnetically driven spray-coating method is reported, and both the spatial density and height of the Fe3 O4 array are tunable upon spraying time. It shows an extremely high solar absorbance (98.6%) in the entire solar spectrum, which is superior to the corresponding 2D Fe3 O4 structure (91.1%). Combining the obtained 3D Fe3 O4 /PET with a yolk-shell hydrophobic/superhydrophilic modified melamine-formaldehyde (mMF) sponge, the carefully designed and fabricated 3D Fe3 O4 /PET-mMF evaporator can realize a high water evaporation rate of 1.59 kg m-2 h-1 under 1 kW m-2 solar illumination, outperforming most related solar steam generation systems. With the advantages of cost-effectiveness, high evaporation rate, reliable endurance, and structural controllability, this 3D structural design provides an avenue to build up high-performance solar energy-driven water steam generation systems.

7.
Mediators Inflamm ; 2022: 4083477, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35990042

RESUMEN

Degradable hemostatic materials have unique advantages in reducing the amount of bleeding, shortening the surgical operation time, and improving patient prognosis. However, none of the current hemostatic materials are ideal and have disadvantages. Therefore, a novel biodegradable cellulose-based composite hemostatic material was prepared by crosslinking sodium carboxymethyl cellulose (CCNa) and hydroxyethyl cellulose (HEC), following an improved vacuum freeze-drying method. The resulting cellulose composite material was neutral in pH and spongy with a density of 0.042 g/cm3, a porosity of 77.68%, and an average pore size of 13.45 µm. The composite's compressive and tensile strengths were 0.1 MPa and 15.2 MPa, respectively. Under in vitro conditions, the composites were degraded gradually through petite molecule stripping and dissolution, reaching 96.8% after 14 days and 100% degradation rate at 21 days. When implanted into rats, the degradation rate of the composite was slightly faster, reaching 99.7% in 14 days and 100% in 21 days. Histology showed a stable inflammatory response and no evidence of cell degeneration, necrosis, or abnormal hyperplasia in the tissues around the embedded material, indicating good biocompatibility. In the hemorrhagic liver model, the time to hemostasis and the total blood loss in the cellulose composite group was significantly lower than in the medical gauze group and the blank control group (P < 0.05). These data indicate that the novel cellulose composite is a promising implantable hemostatic material in clinical settings.


Asunto(s)
Hemostáticos , Animales , Celulosa/química , Hemorragia , Hemostasis , Hemostáticos/química , Ratas
8.
J Am Chem Soc ; 143(37): 15440-15452, 2021 09 22.
Artículo en Inglés | MEDLINE | ID: mdl-34478267

RESUMEN

Neutral ketene is a crucial intermediate during zeolite carbonylation reactions. In this work, the roles of ketene and its derivates (viz., acylium ion and surface acetyl) associated with direct C-C bond coupling during the carbonylation reaction have been theoretically investigated under realistic reaction conditions and further validated by synchrotron radiation X-ray diffraction (SR-XRD) and Fourier transformed infrared (FT-IR) studies. It has been demonstrated that the zeolite confinement effect has significant influence on the formation, stability, and further transformation of ketene. Thus, the evolution and the role of reactive and inhibitive intermediates depend strongly on the framework structure and pore architecture of the zeolite catalysts. Inside side pockets of mordenite (MOR), rapid protonation of ketene occurs to form a metastable acylium ion exclusively, which is favorable toward methyl acetate (MA) and acetic acid (AcOH) formation. By contrast, in 12MR channels of MOR, a relatively longer lifetime was observed for ketene, which tends to accelerate deactivation of zeolite due to coke formation by the dimerization of ketene and further dissociation to diene and alkyne. Thus, we resolve, for the first time, a long-standing debate regarding the genuine role of ketene in zeolite catalysis. It is a paradigm to demonstrate the confinement effect on the formation, fate, and catalytic consequence of the active intermediates in zeolite catalysis.

9.
Biochem Biophys Res Commun ; 569: 1-9, 2021 09 10.
Artículo en Inglés | MEDLINE | ID: mdl-34216991

RESUMEN

Glioblastoma multiforme (GBM) is the most common primary malignant brain tumor without curable therapy. Surgical resection remains the first choice of patients with GBM but tumors relapse rapidly even combined with conventional chemoradiotherapy. The mechanism of GBM rapid recurrence is poorly understood, which is largely due to the lack of an appropriate animal model, thus heavily impedes the improvement of postoperative therapy. Here we established a highly reproducible mouse GBM surgical model by using the syngeneic G422TN-GBM cells, which faithfully recapitulates the features of rapid recurrence of human GBM after surgery. Implanting 2 × 103-5 × 104 of G422TN-GBM cells in mouse cerebral cortex caused death in all animal within 23 days, while surgery was an effective therapy but not curable. After complete removal of visible tumors on day 5-9 of tumor growth, the tumors recurred macroscopically within 5 days accompanied by increasing infiltrative cancer foci. Mechanistically, the rapid recurrence of resected tumors was positively correlated to early Akt activation, which subsequently upregulated PD-L1/Vimentin and promoted proliferation/migration of cancer cells. In addition, environmental astrocytic activation with strong PD-L1 signal was prominent. Taken together, we provided a novel GBM surgical recurrence model for preclinical studies and suggested complicated recurring mechanisms involving in strong oncogenic signaling as well as immune inhibitory signals from both GBM cells and their neighboring astrocytes.


Asunto(s)
Antígeno B7-H1/metabolismo , Neoplasias Encefálicas/metabolismo , Glioblastoma/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Transducción de Señal , Vimentina/metabolismo , Animales , Neoplasias Encefálicas/cirugía , Neoplasias Encefálicas/terapia , Línea Celular Tumoral , Terapia Combinada , Modelos Animales de Enfermedad , Glioblastoma/cirugía , Glioblastoma/terapia , Humanos , Estimación de Kaplan-Meier , Masculino , Ratones , Microscopía Fluorescente/métodos , Recurrencia Local de Neoplasia
10.
Scand J Immunol ; 94(3): e13087, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35226388

RESUMEN

In recent years, immune checkpoint inhibitor (ICI) therapy has revolutionized the treatment of patients with advanced-stage non-small cell lung cancer (NSCLC). The relationship between TP53 mutation and prognosis of non-small cell lung cancer (NSCLC) remains controversial. We aimed to identify advanced-stage NSCLC patients harboring TP53 mutation who would benefit from ICI treatment. Gene mutations and tumor mutational burden (TMB) data of NSCLC patients who received at least one dose of ICI therapy at the Memorial Sloan Kettering Cancer Center between 2013 and 2017 were extracted from the cBioPortal online platform. Gene clustering analyses were performed for patients with short and long overall survival (OS). The top ten significantly different mutated genes were identified. Furthermore, we analyzed the different OS of coexisting TP53 and other significantly different mutated genes to identify NSCLC patients with TP53 mutations who would benefit from immunotherapy. A total of 350 patients were enrolled in the study. Of these a total of 219 (62.6%) patients were found to harbor TP53 mutations, whereas 131 (37.4%) had wild-type TP53. There was no statistically significant difference in OS between TP53 mutated or wild-type NSCLC patients who underwent ICI treatment. However, coexisting TP53 and ZFHX3 mutations were independent prognostic factors. Higher somatic TMB (highest 20% in each histology) and combination of anti-CTLA-4 and anti-PD-1/PD-L1 therapy were also associated with longer OS in multivariate analysis. Coexisting TP53 and ZFHX3 mutations are independent prognostic factors for advanced-stage NSCLC patients undergoing ICI treatment. These findings could help identify patients harboring TP53 mutations that would benefit from ICI treatment.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/genética , Proteínas de Homeodominio/genética , Inhibidores de Puntos de Control Inmunológico/uso terapéutico , Neoplasias Pulmonares/genética , Proteína p53 Supresora de Tumor/genética , Adulto , Anciano , Anciano de 80 o más Años , Antígeno B7-H1/antagonistas & inhibidores , Antígeno CTLA-4/antagonistas & inhibidores , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/patología , Femenino , Humanos , Inmunoterapia/métodos , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/patología , Masculino , Persona de Mediana Edad , Pronóstico , Receptor de Muerte Celular Programada 1/antagonistas & inhibidores , Carga Tumoral/efectos de los fármacos
11.
Langmuir ; 37(31): 9630-9636, 2021 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-34333978

RESUMEN

Multifunctional surfaces that are favorable for both droplet nucleation and removal are critical for water-harvesting applications, but there still remain great challenges. Herein, we proposed a facile strategy to construct hydrophobic surfaces containing moderate hydrophilic groups to achieve both exceptional droplet nucleation and removal. Different from natural desert beetle-inspired water-harvesting materials, these surfaces utilize limited hydrophilic domains to condense fog, and transport of formed tiny droplets relies on a hydrophobic background. The total surface area of the presented hydrophobic fabric contains hydrophilic groups, and the areas for trapping fog have increased. This feature is optimized to enhance the droplet nucleation density, and the surface still has excellent liquid repellency, resulting in maximum water collection efficiency of the prepared surface reaching up to 3.145 g·cm-2·h-1, much higher than the most reported water-harvesting materials. Due to its high efficiency and scalability, we believe that the proposed strategy to construct hydrophobic surfaces containing hydrophilic groups has great practical value.

12.
J Appl Clin Med Phys ; 22(5): 79-88, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33817981

RESUMEN

PURPOSE: To evaluate dosimetric properties of intensity-modulated proton therapy (IMPT) for simulated treatment planning in patients with atrial fibrillation (AF) targeting left atrial-pulmonary vein junction (LA-PVJ), in comparison with volumetric-modulated arc therapy (VMAT) and helical tomotherapy (TOMO). METHODS: Ten thoracic 4D-CT scans with respiratory motion and one with cardiac motion were used for the study. Ten respiratory 4D-CTs were planned with VMAT, TOMO, and IMPT for simulated AF. Targets at the LA-PVJ were defined as wide-area circumferential ablation line. A single fraction of 25 Gy was prescribed to all plans. The interplay effects from cardiac motion were evaluated based on the cardiac 4D-CT scan. Dose-volume histograms (DVHs) of the ITV and normal tissues were compared. Statistical analysis was evaluated via one-way Repeated-Measures ANOVA and Friedman's test with Bonferroni's multiple comparisons test. RESULTS: The median volume of ITV was 8.72cc. All plans had adequate target coverage (V23.75Gy  ≥ 99%). Compared with VMAT and TOMO, IMPT resulted in significantly lower dose of most normal tissues. For VMAT, TOMO, and IMPT plans, Dmean of the whole heart was 5.52 ± 0.90 Gy, 5.89 ± 0.78 Gy, and 3.01 ± 0.57 Gy (P < 0.001), mean dose of pericardium was 4.74 ± 0.76 Gy, 4.98 ± 0.62 Gy, and 2.59 ± 0.44 Gy (P < 0.001), and D0.03cc of left circumflex artery (LCX) was 13.96 ± 5.45 Gy, 14.34 ± 5.91 Gy, and 8.43 ± 7.24 Gy (P < 0.001), respectively. However, no significant advantage for one technique over the others was observed when examining the D0.03cc of esophagus and main bronchi. CONCLUSIONS: IMPT targeting LA-PVJ for patients with AF has high potential to reduce dose to surrounding tissues compared to VMAT or TOMO. Motion mitigation techniques are critical for a particle-therapy approach.


Asunto(s)
Fibrilación Atrial , Terapia de Protones , Venas Pulmonares , Radioterapia de Intensidad Modulada , Fibrilación Atrial/cirugía , Estudios de Factibilidad , Humanos , Órganos en Riesgo , Venas Pulmonares/diagnóstico por imagen , Venas Pulmonares/cirugía , Dosificación Radioterapéutica , Planificación de la Radioterapia Asistida por Computador
13.
Small ; 15(31): e1901888, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31192535

RESUMEN

Tunable underwater oil adhesion is a critical issue in interfacial science and industrial applications. Although much progress has been made to date, development of novel smart coating materials that can selectively change the wetting property at different areas is considerably scarce. Here, a simple strategy is proposed to fabricate photothermal responsive coatings, which can change the oil adhesion behavior from low-adhesive rolling state to high-adhesive pinning state for a variety of oily liquids in a remote, local, and reversible manner. Owing to this unique controllability, the adhesion and no-adhesion of oil droplets on the coated surfaces can be easily manipulated by remote and local near-infrared radiation.

14.
Small ; 15(24): e1901161, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-31045324

RESUMEN

Carbon dots (CDots)-based solid-state luminescent materials have important applications in light-emitting devices owing to their outstanding optical properties. However, it still remains a challenge to develop multiple-color-emissive solid-state CDots, due to the serious self-quenching of the CDots in the aggregation or solid state. Herein, a one-step synthesis of multiple-color-emissive solid-state silica-coated CDots (silica/CDots) composites by controlling CDots loading fraction and composite morphology to realize the adjustment of emitting color is reported. The emission of resultant silica/CDots composites shifts from blue to orange with the photoluminescence quantum yields of 57.9%, 34.3%, and 32.7% for blue, yellow, and orange emitting, respectively. Furthermore, the yellow emitting silica/CDots composites exhibit an excellent fluorescence thermal stability, and further have been applied to fabricate white-light-emitting devices with a high color rendering index of above 80.

15.
Chem Rev ; 117(19): 12475-12531, 2017 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-28952317

RESUMEN

Acid-base catalytic reaction, either in heterogeneous or homogeneous systems, is one of the most important chemical reactions that has provoked a wide variety of industrial catalytic processes for production of chemicals and petrochemicals over the past few decades. In view of the fact that the catalytic performances (e.g., activity, selectivity, and reaction mechanism) of acid-catalyzed reactions over acidic catalysts are mostly dictated by detailed acidic features, viz. type (Brønsted vs Lewis acidity), amount (concentration), strength, and local environments (location) of acid sites, information on and manipulation of their structure-activity correlation are crucial for optimization of catalytic performances as well as innovative design of novel effective catalysts. This review aims to summarize recent developments on acidity characterization of solid and liquid catalysts by means of experimental 31P nuclear magnetic resonance (NMR) spectroscopy using phosphorus probe molecules such as trialkylphosphine (TMP) and trialkylphosphine oxides (R3PO). In particular, correlations between the observed 31P chemical shifts (δ31P) of phosphorus (P)-containing probes and acidic strengths have been established in conjuction with density functional theory (DFT) calculations, rendering practical and reliable acidity scales for Brønsted and Lewis acidities at the atomic level. As illustrated for a variety of different solid and liquid acid systems, such as microporous zeolites, mesoporous molecular sieves, and metal oxides, the 31P NMR probe approaches were shown to provide important acid features of various catalysts, surpassing most conventional methods such as titration, pH measurement, Hammett acidity function, and some other commonly used physicochemical techniques, such as calorimetry, temperature-programmed desorption of ammonia (NH3-TPD), Fourier transformed infrared (FT-IR), and 1H NMR spectroscopies.

16.
Mikrochim Acta ; 186(2): 59, 2019 01 07.
Artículo en Inglés | MEDLINE | ID: mdl-30617429

RESUMEN

A hydrothermal route is reported for the preparation of a composite consisting of sheet-like glucose-derived carbon and nickel oxide nanoparticles. The nanocomposites were prepared at different annealing temperatures and exploited as electrode materials for amperometric (i-t) determination of hydrazine (N2H4) and hydrogen peroxide (H2O2) at trace levels. The performances of the sensors were assessed by cyclic voltammetry and amperometry detection using a rotating disk electrode (RDE) technique. The modified electrode annealed at ca. 300 °C was found to exhibit the best electrocatalytic performance in terms of sensitive and selective detection of N2H4 and H2O2 even in the presence of interfering species. The electrode is inexpensive, robust, easy to prepare in large batches, highly stable, and has a low overpotential. H2O2 can be sensed, best at a working voltage of typically 0.13 V vs Ag/AgCl; rotationg speed 1200 rpm) over a wide concentration range (0.01 to 3.9 µM) with a detection limit of 1.5 nM. N2H4 can be sensed, best at a working voltage of typically 0.0 V within the concentration range from 0.5 µM to 12 mM with an excellent detection limit of 1.5 µM. Thus, this cost-effective and robust modified electrode, which may be readily prepared in large batch quantity, represents a practical platform for industrial sensing. Graphical abstract Schematic of the hydrothermal method for synthesis of carbon and nickel oxide nanoparticle composites (GCD/NiO-150, GCD/NiO-300, and GCD/NiO-450). The composite was used for the electro-oxidation of hydrazine (N2H4) and hydrogen peroxide (H2O2) by cyclic voltammetry and amperometry (i-t).

17.
J Am Chem Soc ; 140(34): 10764-10774, 2018 08 29.
Artículo en Inglés | MEDLINE | ID: mdl-30070481

RESUMEN

Post-synthetic dealumination treatment is a common tactic adopted to improve the catalytic performance of industrialized zeolitic catalysts through enhancements in acidity and stability. However, among the possible extra-framework aluminum (EFAL) species in dealuminated zeolites such as Al3+, Al(OH)2+, Al(OH)2+, AlO+, AlOOH, and Al(OH)3, the presence of tri-coordinated EFAL-Al3+ species, which exhibit large quadrupolar effect due to the lack of hydrogen-bonding species, was normally undetectable by conventional one- and two-dimensional 1H and/or 27Al solid-state nuclear magnetic resonance (SSNMR) techniques. By combining density functional theory (DFT) calculations with experimental 31P SSNMR using trimethylphosphine (TMP) as the probe molecule, we report herein a comprehensive study to certify the origin, fine structure, and possible location of tri-coordinated EFAL-Al3+ species in dealuminated HY zeolite. The spatial proximities and synergies between the Brønsted and various Lewis acid sites were clearly identified, and the origin for the observed EFAL-Al3+ species with ultra-strong Lewis acidity was deduced to be at the expense of adjacent Brønsted acid sites. The excellent performance of such tri-coordinated EFAL species was furthermore confirmed by glucose isomerization reactions.

18.
Biochim Biophys Acta Mol Basis Dis ; 1864(5 Pt A): 1754-1769, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29510196

RESUMEN

Glioblastoma multiforme (GBM) is the most aggressive primary brain tumor due to the lack of effective therapeutic drugs. Cancer therapy targeting programmed cell death protein 1 (PD-1) or programmed death ligand-1 (PD-L1) is of revolutionary. However, the role of intrinsic PD-L1, which determines immune-therapy outcomes, remains largely unclear. Here we demonstrated an oncogenic role of PD-L1 via binding and activating Ras in GBM cells. RNA-sequencing transcriptome data revealed that PD-L1 significantly altered gene expression enriched in cell growth/migration/invasion pathways in human GBM cells. PD-L1 overexpression and knockout or knockdown demonstrated that PD-L1 promoted GBM cell proliferation and migration in vitro and in vivo. Mechanistically, PD-L1 prominently activated epithelial mesenchymal transition (EMT) process in a MEK/Erk- but not PI3K/Akt-dependent manner. Further, we identified intracellular interactions of PD-L1 and H-Ras, which led to Ras/Erk/EMT activation. Finally, we demonstrated that PD-L1 overexpression promoted while knockdown abolished GBM development and invasion in orthotopic GBM models of rodents. Taken together, we found that intracellular PD-L1 confers GBM cell malignancy and aggressiveness via binding Ras and activating the downstream Erk-EMT signaling. Thus, these results shed important insights in improving efficacy of immune therapy for GBM as well as other malignant tumors.


Asunto(s)
Antígeno B7-H1/metabolismo , Transición Epitelial-Mesenquimal , Glioblastoma/metabolismo , Sistema de Señalización de MAP Quinasas , Animales , Antígeno B7-H1/genética , Quinasas MAP Reguladas por Señal Extracelular/genética , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Glioblastoma/genética , Glioblastoma/patología , Humanos , Hielo , Masculino , Ratones Endogámicos BALB C , Ratones Desnudos , Fosfatidilinositol 3-Quinasas/genética , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/genética , Proteínas Proto-Oncogénicas c-akt/metabolismo , Proteínas Proto-Oncogénicas p21(ras)/genética , Proteínas Proto-Oncogénicas p21(ras)/metabolismo , Ratas , Ratas Sprague-Dawley
19.
Chem Rec ; 18(4): 410-432, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29124869

RESUMEN

Polydopamine is a synthetic analogue of natural melanin (eumelanin) produced from oxidative polymerization of dopamine. Owing to its strong adhesion ability, versatile chemical reactivity, biocompatibility and biodegradation, polydopamine is commonly applied as a versatile linker to synthesize colloidal materials with diverse structures, unique physicochemical properties and tunable functions, which allow for a broad scope of applications including biomedicine, sensing, catalysis, environment and energy. In this personal account, we discuss first about the different synthetic approaches of polydopamine, as well as its polymerization mechanism, and then with a comprehensive overview of recent progress in the synthesis and applications of polydopamine-based colloidal materials. Finally, we summarize this personal account with future perspectives.

20.
Biochem Biophys Res Commun ; 488(1): 33-39, 2017 06 17.
Artículo en Inglés | MEDLINE | ID: mdl-28476618

RESUMEN

Glioblastoma multiforme (GBM) is a highly aggressive brain tumor with a median survival time of only 14 months after treatment. It is urgent to find new therapeutic drugs that increase survival time of GBM patients. To achieve this goal, we screened differentially expressed genes between long-term and short-term survived GBM patients from Gene Expression Omnibus database and found gene expression signature for the long-term survived GBM patients. The signaling networks of all those differentially expressed genes converged to protein binding, extracellular matrix and tissue development as revealed in BiNGO and Cytoscape. Drug repositioning in Connectivity Map by using the gene expression signature identified repaglinide, a first-line drug for diabetes mellitus, as the most promising novel drug for GBM. In vitro experiments demonstrated that repaglinide significantly inhibited the proliferation and migration of human GBM cells. In vivo experiments demonstrated that repaglinide prominently prolonged the median survival time of mice bearing orthotopic glioma. Mechanistically, repaglinide significantly reduced Bcl-2, Beclin-1 and PD-L1 expression in glioma tissues, indicating that repaglinide may exert its anti-cancer effects via apoptotic, autophagic and immune checkpoint signaling. Taken together, repaglinide is likely to be an effective drug to prolong life span of GBM patients.


Asunto(s)
Carbamatos/farmacología , Carbamatos/uso terapéutico , Glioblastoma/tratamiento farmacológico , Piperidinas/farmacología , Piperidinas/uso terapéutico , Animales , Carbamatos/administración & dosificación , Supervivencia Celular/efectos de los fármacos , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Glioblastoma/metabolismo , Glioblastoma/patología , Humanos , Ratones , Ratones Endogámicos C57BL , Piperidinas/administración & dosificación , Relación Estructura-Actividad , Células Tumorales Cultivadas
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