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1.
Biomaterials ; 296: 122069, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36893653

RESUMO

The valid management of inflammation and precise inhibition of smooth muscle cells (SMCs) is regarded as a promising strategy for regulating vascular responses after stent implantation, yet posing huge challenges to current coating constructions. Herein, we proposed a spongy cardiovascular stent for the protective delivery of 4-octyl itaconate (OI) based on a "spongy skin" approach, and revealed the dual-regulation effects of OI for improving vascular remolding. We first constructed a "spongy skin" onto poly-l-lactic acid (PLLA) substrates, and realized the protective loading of OI with the highest dosage of 47.9 µg/cm2. Then, we verified the remarkable inflammation mediation of OI, and surprisingly revealed that the OI incorporation specifically inhibited SMC proliferation and phenotype switching, which contributed to the competitive growth of endothelial cells (EC/SMC ratio âˆ¼ 5.1). We further demonstrated that OI at a concentration of 25 µg/mL showed significant suppression of the TGF-ß/Smad pathway of SMCs, leading to the promotion of contractile phenotype and reduction of extracellular matrix. In vivo evaluation indicated that the successful delivery of OI fulfilled the inflammation regulation and SMCs inhibition, therefore suppressing the in-stent restenosis. This "spongy skin" based OI eluting system may serve as a new strategy for improving vascular remolding, and provides a potential concept for the treatment of cardiovascular diseases.


Assuntos
Reestenose Coronária , Humanos , Reestenose Coronária/prevenção & controle , Células Endoteliais/metabolismo , Stents , Inflamação/metabolismo
2.
Chemistry ; 28(32): e202201391, 2022 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-35575466

RESUMO

Invited for the cover of this issue are Chih-Min Wang and co-workers at Academia Sinica of Taiwan and National Taiwan Ocean University. The image depicts an unusual organic-inorganic hybrid zinc phosphite with interesting structural features and gas adsorption properties. Read the full text of the article at 10.1002/chem.202200732.


Assuntos
Dióxido de Carbono , Adsorção , Humanos , Fosfitos
3.
Colloids Surf B Biointerfaces ; 214: 112483, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35366576

RESUMO

Changes in the stiffness of the cellular microenvironment are involved in many pathological processes of blood vessels. Substrate stiffness has been shown to have extensive effects on vascular endothelial cells (VECs) and vascular smooth muscle cells (VSMCs). However, the material stiffness of most previously reported in-vitro models is ranging from ~100 kPa to the magnitude of MPa, which does not match the mechanical properties of natural vascular tissue (10-100 kPa). Herein, we constructed hydrogel substrates with the stiffness of 18-86 kPa to explore the effect of physiological stiffness on vascular cells. Our findings show that, with the increase of stiffness at the physiological range, the cell adhesion and proliferation behaviors of VECs and VSMCs are significantly enhanced. On the soft substrate, VECs express more nitric oxide (NO), and VSMCs tend to maintain a healthy contraction phenotype. More importantly, we find that the number of differentially expressed genes in cells cultured between 18 kPa and 86 kPa substrates (560 in VECs, 243 in VSMCs) is significantly higher than that between 86 kPa and 333 kPa (137 in VECs, 172 in VSMCs), indicating that a small increase in stiffness within the physiological range have a higher impact on vascular cell behaviors. Overall, our results expanded the exploration of how stiffness affects the behavior of vascular cells at the physiological range.


Assuntos
Células Endoteliais , Músculo Liso Vascular , Adesão Celular , Proliferação de Células , Células Cultivadas , Miócitos de Músculo Liso
4.
Chemistry ; 28(32): e202200732, 2022 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-35429358

RESUMO

An uncommon example of stable mixed-ligand zinc phosphite with genuine pores has been synthesized by using zinc metal, inorganic phosphite acid, thio-functionalized O-donor (2,5-thiophenedicarboxylate, TPDC), and tetradentate N-donor [1,2,4,5-tetrakis(imidazol-1-ylmethyl)benzene, TIMB] units assembled into one crystalline structure according to a hydro(solvo)thermal method. This is a very rare case of a metal phosphite incorporating both N- and O-donor ligands. The tetradentate TIMB linker bound to zinc atoms of the isolated zincophosphite hexamers to form a 3D open-framework structure by crosslinking structural components of 1D chains and 2D layers. Here, the TPDC ligand acts as a monodentate binding model to functionalize its porous structure with the uncoordinated S atom and COO- group. Interestingly, this compound demonstrates the highest H2 storage capacity among organic-inorganic hybrid metal phosphates (and phosphites), and a good CO2 capture at 298 K compared with the majority of crystalline materials. The possible adsorption sites and selectivity for CO2 over H2 , N2 , and CO at 298 K were calculated by using density functional theory (DFT), the ideal adsorption solution theory (IAST), and fitting experimental pure-component adsorption data.

5.
Opt Lett ; 47(2): 429-432, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-35030621

RESUMO

In this work, a GaN-based UV photodetector with an asymmetric electrode structure was fabricated by atomic layer deposition (ALD) of TiN layers. The thickness of the TiN can be monitored in situ by a quartz crystal microbalance (QCM) and precisely controlled through the modulation of deposition cycles. During the ALD process, periodic variation in the QCM frequency was observed and correlated to the physical adsorption, chemical bonding, and the excessive precursor exhaust, which included tetrakis(dimethylamino)titanium (TDMAT) and N sources. The asymmetric TiN/GaN/TiN photodetector showed excellent photosensing performance, with a UV-visible rejection ratio of 173, a responsivity of 4.25 A/W, a detectivity of 1.1×1013 Jones, and fast response speeds (a rise time of 69 µs and a decay time of 560 µs). Moreover, the device exhibits high stability, with an attenuation of only approximately 0.5% after 360 nm light irradiation for 157 min. This result indicates the potential of TiN as a transparent contact electrode for GaN-based optoelectronic devices.

6.
J Mater Chem B ; 10(14): 2454-2462, 2022 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-34698745

RESUMO

Thrombus and restenosis after stent implantation are the major complications because traditional drugs such as rapamycin delay the process of endothelialization. Nitric oxide (NO) is mainly produced by endothelial nitric oxide synthase (eNOS) on the membrane of endothelial cells (ECs) in the cardiovascular system and plays an important role in vasomotor function. It strongly inhibits the proliferation of smooth muscle cells (SMCs) and ameliorates endothelial function when ECs get hurt. Inspired by this, introducing NO to traditional stent coating may alleviate endothelial insufficiency caused by rapamycin. Here, we introduced SNAP as the NO donor, mimicking how NO affects in vivo, into rapamycin coating to alleviate endothelial damage while inhibiting SMC proliferation. Through wicking effects, SNAP was absorbed into a hierarchical coating that had an upper porous layer and a dense polymer layer with rapamycin at the bottom. Cells were cultured on the coatings, and it was observed that the injured ECs were restored while the growth of SMCs further diminished. Genome analysis was conducted to further clarify possible signaling pathways: the effect of cell growth attenuated by NO may cause by affecting cell cycle and enhancing inflammation. These findings supported the idea that introducing NO to traditional drug-eluting stents alleviates incomplete endothelialization and further inhibits the stenosis caused by the proliferation of SMCs.


Assuntos
Stents Farmacológicos , Células Endoteliais , Miócitos de Músculo Liso , Óxido Nítrico/farmacologia , Sirolimo/farmacologia
7.
Ann Surg Oncol ; 29(1): 572-585, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34387767

RESUMO

BACKGROUND: Multidisciplinary management strategies are standard in esophageal cancer. Based on a multidisciplinary tumor board (MTB) database in a high-volume center, we aimed to evaluate real-world treatment patterns and patient outcomes in patients with esophageal cancer. In addition, we determined the impact of MTB discussions on patient prognosis. METHODS: Patients diagnosed with esophageal cancer between 2010 and 2019 were retrospectively reviewed. The pattern of treatment modalities and overall survival (OS) of patients with limited, locally advanced, and advanced/metastatic disease were reported. RESULTS: Data from 1132 patients, including 247 patients with limited esophageal cancer, 606 patients with locally advanced esophageal cancer, and 279 patients with advanced/metastatic esophageal cancer were included. Upfront surgery was the most common (56.3%) treatment modality for patients with limited esophageal cancer, while treatment for locally advanced esophageal cancer included upfront surgery (19.1%), neoadjuvant chemoradiotherapy (44.9%), and definitive chemoradiotherapy (36.0%); however, 27.9% of patients undergoing neoadjuvant chemoradiotherapy did not receive planned esophagectomy. Definitive chemoradiotherapy was mainly used for patients with locally advanced and advanced/metastatic disease, but had an incompletion rate of 22.0% and 33.7%, respectively. Regarding survival, the 5-year OS rates were 56.4%, 26.3%, and 5.1% in patients with limited, locally advanced, and advanced/metastatic disease, respectively. Additionally, patients whose clinical management was discussed in the MTB had a significantly better 5-year OS rate than the other patients (27.3% vs. 20.5%, p < 0.001). CONCLUSIONS: We report the real-world data of treatment patterns and patient outcomes in patients with esophageal cancer with respect to multidisciplinary management, and demonstrate the positive impact of MTB discussions on patient prognosis.


Assuntos
Neoplasias Esofágicas , Estudos Interdisciplinares , Neoplasias Esofágicas/terapia , Humanos , Estudos Retrospectivos
8.
ACS Appl Mater Interfaces ; 13(49): 58799-58808, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34859991

RESUMO

Bismuth oxyhalides (BiOX, X = F, Cl, Br, I) are emerging energy materials because of their remarkable catalytic activity. The BiOX compounds usually have a tetragonal type crystal structure with unique layered morphology consisting of [X-Bi-O-Bi-X] sheets. Although the BiOX nanosheets exposed with {001} facets perform superior photoactivity, there is lack of understanding about their capability in the electrochemical CO2 reduction reaction (CO2RR). Herein, we adopt wet-chemical syntheses to make 2D BiOCl and Pd-doped BiOCl nanosheets for CO2RR. In the results, formic acid is the only one kind of product converted from CO2 along with H2 gas from water reduction over both BiOCl and Pd-doped BiOCl nanosheets. By thorough analyses with ex situ and in situ spectroscopy, the results reflect that (1) metallic Bi0 atoms generated by the applied negative potentials serve as the catalytic sites for the hydrogen evolution reaction (HER) and CO2RR and (2) the existence of doped Pd ions in the BiOCl structure reduces the barrier of charge transfer over the nanosheets, which enhances HER and CO2RR activities. We believe that the observations are important references for making catalysts toward CO2RR performance.

9.
ACS Appl Mater Interfaces ; 13(44): 51809-51828, 2021 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-34310110

RESUMO

Professor Chia-Kuang (Frank) Tsung made his scientific impact primarily through the atomic-level design of nanoscale materials for application in heterogeneous catalysis. He approached this challenge from two directions: above and below the material surface. Below the surface, Prof. Tsung synthesized finely controlled nanoparticles, primarily of noble metals and metal oxides, tailoring their composition and surface structure for efficient catalysis. Above the surface, he was among the first to leverage the tunability and stability of metal-organic frameworks (MOFs) to improve heterogeneous, molecular, and biocatalysts. This article, written by his former students, seeks first to commemorate Prof. Tsung's scientific accomplishments in three parts: (1) rationally designing nanocrystal surfaces to promote catalytic activity; (2) encapsulating nanocrystals in MOFs to improve catalyst selectivity; and (3) tuning the host-guest interaction between MOFs and guest molecules to inhibit catalyst degradation. The subsequent discussion focuses on building on the foundation laid by Prof. Tsung and on his considerable influence on his former group members and collaborators, both inside and outside of the lab.

10.
Bioact Mater ; 6(12): 4686-4696, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34095625

RESUMO

The in-stent restenosis (IRS) after the percutaneous coronary intervention contributes to the major treatment failure of stent implantation. MicroRNAs have been revealed as powerful gene medicine to regulate endothelial cells (EC) and smooth muscle cells (SMC) in response to vascular injury, providing a promising therapeutic candidate to inhibit IRS. However, the controllable loading and eluting of hydrophilic bioactive microRNAs pose a challenge to current lipophilic stent coatings. Here, we developed a microRNA eluting cardiovascular stent via the self-healing encapsulation process based on an amphipathic poly(ε-caprolactone)-poly(ethylene glycol)-poly(ε-caprolactone) (PCL-PEG-PCL, PCEC) triblock copolymer spongy network. The miR-22 was used as a model microRNA to regulate SMC. The dynamic porous coating realized the uniform and controllable loading of miR-22, reaching the highest dosage of 133 pmol cm-2. We demonstrated that the sustained release of miR-22 dramatically enhanced the contractile phenotype of SMC without interfering with the proliferation of EC, thus leading to the EC dominating growth at an EC/SMC ratio of 5.4. More importantly, the PCEC@miR-22 coated stents showed reduced inflammation, low switching of SMC phenotype, and low secretion of extracellular matrix, which significantly inhibited IRS. This work provides a simple and robust coating platform for the delivery of microRNAs on cardiovascular stent, which may extend to other combination medical devices, and facilitate practical application of bioactive agents in clinics.

11.
Nano Lett ; 20(9): 6630-6635, 2020 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-32786948

RESUMO

It has been reported that the biological functions of enzymes could be altered when they are encapsulated in metal-organic frameworks (MOFs) due to the interactions between them. Herein, we probed the interactions of catalase in solid and hollow ZIF-8 microcrystals. The solid sample with confined catalase is prepared through a reported method, and the hollow sample is generated by hollowing the MOF crystals, sealing freestanding enzymes in the central cavities of hollow ZIF-8. During the hollowing process, the samples were monitored by small-angle X-ray scattering (SAXS) spectroscopy, electron microscopy, powder X-ray diffraction (PXRD), and nitrogen sorption. The interfacial interactions of the two samples were studied by infrared (IR) and fluorescence spectroscopy. IR study shows that freestanding catalase has less chemical interaction with ZIF-8 than confined catalase, and a fluorescence study indicates that the freestanding catalase has lower structural confinement. We have then carried out the hydrogen peroxide degradation activities of catalase at different stages and revealed that the freestanding catalase in hollow ZIF-8 has higher activity.


Assuntos
Estruturas Metalorgânicas , Catalase , Enzimas Imobilizadas , Espalhamento a Baixo Ângulo , Difração de Raios X
12.
Chemistry ; 26(57): 12931-12935, 2020 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-32374926

RESUMO

DNAzymes are a promising class of bioinspired catalyst; however, their structural instability limits their potential. Herein, a method to stabilize DNAzymes by encapsulating them in a metal-organic framework (MOF) host is reported. This biomimetic mineralization process makes DNAzymes active under a wider range of conditions. The concept is demonstrated by encapsulating hemin-G-quadruplex (Hemin-G4) into zeolitic imidazolate framework-90 (ZIF-90), which indeed increases the DNAzyme's structural stability. The stabilized DNAzymes show activities in the presence of Exonuclease I, organic solvents, or high temperature. Owing to its elevated stability and heterogeneous nature, it is possible to perform catalysis under continuous-flow conditions, and the DNAzyme can be reactivated in situ by introducing K+ . Moreover, it is found that the encapsulated DNAzyme maintains its high enantiomer selectivity, demonstrated by the sulfoxidation of thioanisole to (S)-methyl phenyl sulfoxide. This concept of stabilizing DNAzymes expands their potential application in chemical industry.


Assuntos
DNA Catalítico , DNA Catalítico/metabolismo , Quadruplex G , Hemina , Estruturas Metalorgânicas
13.
Asian J Anesthesiol ; 58(4): 138-145, 2020 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-33550770

RESUMO

BACKGROUND: Betel-nut chewing (BC) causes oral submucous fibrosis (OSF), and this leads to difficult tracheal intubation (DI). Unanticipated DI was reported in chewers with apparently normal preoperative airway evaluations (PAEs). This analysis aims to investigate whether BC is an independent risk on DI besides the common DI risk prediction factors. METHODS: After the approval of Institutional Review Board and the written informed consent were obtained, 2,682 patients were enrolled in a cohort. PAEs, intubation difficulty scale (IDS), intubation time, and perceived DI were recorded prospectively. All 805 male patients received classical intubation, 307 with BC and 498 without BC were analyzed. Data were analyzed by Student's t-test and chi-square test. Stepwise logistic regression was performed to identify BC effects on IDS adjusting for related factors with WEKA (Waikato Environment for Knowledge Analysis; Machine Learning Group at the University of Waikato, Hamilton, New Zealand). RESULTS: Fewer BC patients were Cormack-Lehane (CL) grade I (38.9% vs. 47.6%) or IDS degree 〞Easy〞 (24.8% vs. 33.5%). Compared with IDS degree 〞Easy〞, patients in the BC group had a significantly higher odds ratio (OR) for 〞Slight + Moderate-Major〞 degree than in the non-BC group (adjusted OR, 1.75; 95% CI, 1.15-2.68). Compared with CL grade I, patients with BC was an independent risk for II (adjusted OR, 1.53; 95% CI, 1.02-2.32) and IV (adjusted OR, 3.25; 95% CI 1.01-10.49). Otherwise, patient's age ≥ 46 and the presence of teeth were also significant risk factors for IDS degree 〞Slight + Moderate-Major〞. CONCLUSION: BC increased not only the tracheal intubation difficulty in patients with apparent OSF but also in patients with PAEs. BC is an independent risk factor besides the commonly used DI prediction factors. We suggest physicians operating on BC patients to be better prepared for DI.


Assuntos
Areca , Fibrose Oral Submucosa , Humanos , Intubação Intratraqueal , Mastigação , Nozes
14.
Nat Commun ; 10(1): 5002, 2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31676820

RESUMO

Metal-organic frameworks (MOFs) have recently garnered consideration as an attractive solid substrate because the highly tunable MOF framework can not only serve as an inert host but also enhance the selectivity, stability, and/or activity of the enzymes. Herein, we demonstrate the advantages of using a mechanochemical strategy to encapsulate enzymes into robust MOFs. A range of enzymes, namely ß-glucosidase, invertase, ß-galactosidase, and catalase, are encapsulated in ZIF-8, UiO-66-NH2, or Zn-MOF-74 via a ball milling process. The solid-state mechanochemical strategy is rapid and minimizes the use of organic solvents and strong acids during synthesis, allowing the encapsulation of enzymes into three prototypical robust MOFs while maintaining enzymatic biological activity. The activity of encapsulated enzyme is demonstrated and shows increased resistance to proteases, even under acidic conditions. This work represents a step toward the creation of a suite of biomolecule-in-MOF composites for application in a variety of industrial processes.


Assuntos
Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo , Estruturas Metalorgânicas/química , Metais/química , Biocatálise , Catalase/química , Catalase/metabolismo , Catalase/ultraestrutura , Eletroforese em Gel de Poliacrilamida , Estabilidade Enzimática , Enzimas Imobilizadas/ultraestrutura , Estruturas Metalorgânicas/síntese química , Microscopia Eletrônica de Varredura , Difração de Pó , beta-Frutofuranosidase/química , beta-Frutofuranosidase/metabolismo , beta-Frutofuranosidase/ultraestrutura , beta-Galactosidase/química , beta-Galactosidase/metabolismo , beta-Galactosidase/ultraestrutura , beta-Glucosidase/química , beta-Glucosidase/metabolismo , beta-Glucosidase/ultraestrutura
15.
ACS Appl Mater Interfaces ; 9(49): 42676-42687, 2017 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-29161503

RESUMO

We report on the new facile synthesis of mesoporous NiO/MnO2 in one step by modifying inverse micelle templated UCT (University of Connecticut) methods. The catalyst shows excellent electrocatalytic activity and stability for both the oxygen evolution reaction (OER) and the oxygen reduction reaction (ORR) in alkaline media after further coating with polyaniline (PANI). For electrochemical performance, the optimized catalyst exhibits a potential gap, ΔE, of 0.75 V to achieve a current of 10 mA cm-2 for the OER and -3 mA cm-2 for the ORR in 0.1 M KOH solution. Extensive characterization methods were applied to investigate the structure-property of the catalyst for correlations with activity (e.g., XRD, BET, SEM, HRTEM, FIB-TEM, XPS, TGA, and Raman). The high electrocatalytic activity of the catalyst closely relates to the good electrical conductivity of PANI, accessible mesoporous structure, high surface area, as well as the synergistic effect of the specific core-shell structure. This work opens a new avenue for the rational design of core-shell structure catalysts for energy conversion and storage applications.

16.
ACS Appl Mater Interfaces ; 8(32): 20802-13, 2016 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-27458646

RESUMO

Efficient bifunctional catalysts for electrochemical oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) are highly desirable due to their wide applications in fuel cells and rechargeable metal air batteries. However, the development of nonprecious metal catalysts with comparable activities to noble metals is still challenging. Here we report a one-step wet-chemical synthesis of Ni-/Mn-promoted mesoporous cobalt oxides through an inverse micelle process. Various characterization techniques including powder X-ray diffraction (PXRD), N2 sorption, transmission electron microscopy (TEM), and scanning electron microscopy (SEM) confirm the successful incorporation of Ni and Mn leading to the formation of Co-Ni(Mn)-O solid solutions with retained mesoporosity. Among these catalysts, cobalt oxide with 5% Ni doping demonstrates promising activities for both ORR and OER, with an overpotential of 399 mV for ORR (at -3 mA/cm(2)) and 381 mV (at 10 mA/cm(2)) for OER. Furthermore, it shows better durability than precious metals featuring little activity decay throughout 24 h continuous operation. Analyses of cyclic voltammetry (CV), X-ray photoelectron spectroscopy (XPS), Raman, and O2-temperature-programmed desorption (O2-TPD) reveal that redox activity of Co(3+) to Co(4+) is crucial for OER performance, while the population of surface oxygen vacancies and surface area determine ORR activities. The comprehensive investigation of the intrinsic active sites for ORR and OER by correlating different physicochemical properties to the electrochemical activities is believed to provide important insight toward the rational design of high-performance electrocatalysts for ORR and OER reactions.

17.
ACS Appl Mater Interfaces ; 8(12): 7834-42, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26954301

RESUMO

A generic one-pot hydrothermal synthesis route has been successfully designed and utilized to in situ grow uniform manganese oxide nanorods and nanowires onto the cordierite honeycomb monolithic substrates, forming a series of nanoarray-based monolithic catalysts. During the synthesis process, three types of potassium salt oxidants have been used with different reduction potentials, i.e., K2Cr2O7, KClO3, and K2S2O8, denoted as HM-DCM, HM-PCR, and HM-PSF, respectively. The different reduction potentials of the manganese source (Mn(2+)) and oxidants induced the formation of manganese oxide nanoarrays with different morphology, surface area, and reactivity of carbon monoxide (CO) oxidation. K2Cr2O7 and KClO3 can induce sharp and long nanowires with slow growth rates due to their low reduction potentials. In comparison, the nanoarrays of HM-PSF presented shorter nanorods but displayed an efficient 90% CO oxidation conversion at 200 °C (T90) without noble-metal loading. Reducibility tests for the three monolithic catalysts by hydrogen temperature-programmed reduction revealed an activation energy order of HM-PSF > HM-DCM > HM-PCR for CO oxidation. The characterizations of oxygen temperature-programmed desorption and X-ray photoelectron spectroscopy indicated the abundant surface-adsorbed oxygen and lattice oxygen contributing to the superior reactivity of HM-PSF. The straightforward synthetic process showed a scalable, low-cost, and template-free method to fabricate manganese oxide nanoarray monolithic catalysts for exhaust treatment.

18.
Inorg Chem ; 54(21): 10163-71, 2015 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-26451851

RESUMO

Due to the excellent catalytic performance of manganese oxide (K-OMS-2) in a wide range of applications, incorporation of various dopants has been commonly applied for K-OMS-2 to acquire additional functionality or activities. However, the understanding of its substitution mechanism with respect to the catalytic performance of doped K-OMS-2 materials remains unclear. Here we present the structural distortion (from tetragonal to monoclinic cell) and morphological evolution in K-OMS-2 materials by doping hexavalent molybdenum. With a Mo-to-Mn ratio of 1:20 (R-1:20) in the preparation, the resultant monoclinic K-OMS-2 shows a small equidimensional particle size (∼15 nm), a high surface area of 213 m(2) g(-1), and greatly improved catalytic activity toward CO oxidation with lower onset temperatures (40 °C) than that of pristine K-OMS-2 (above 130 °C). HR-TEM analyses reveal direct evidence of structural distortion on the cross-section of 2 × 2 tunnels with the absence of 4-fold rotation symmetry expected for a tetragonal cell, which are indexed using a monoclinic cell. Our results suggest that substitution of Mo(6+) for Mn(3+) (rather than Mn(4+)) coupled with the vacancy generation results in a distorted structure and unique morphology. The weakened Mn-O bonds and Mn vacancies associated with the structural distortion may be mainly responsible for the enhanced catalytic activity of monoclinic K-OMS-2 instead of dopant species.

19.
Jpn J Clin Oncol ; 45(9): 819-27, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26056323

RESUMO

OBJECTIVE: This multicenter Phase II trial evaluated the toxicity/efficacy of gemcitabine plus cisplatin as first-line chemotherapy in patients with recurrent/metastatic nasopharyngeal carcinoma. METHODS: Gemcitabine 1250 mg/m(2) on Days 1 and 8 and cisplatin 75 mg/m(2) on Day 1 were administered at a 3-week interval. The primary endpoint was the response rate. Secondary endpoints included progression-free survival, overall survival, response duration and safety. RESULTS: Fifty-two patients were recruited between 2004 and 2008. The response rate was 51.9% (complete remission rate, 9.6%) in the intent-to-treat group. The median progression-free and overall survivals were 9.8 and 14.6 months, respectively. The major Grade III/IV adverse event was leucopenia (61.6%). The mean number of cycles was 6.63 ± 0.40. The regimen was well-tolerated, although one treatment-related death occurred after severe sepsis from aspiration pneumonia. CONCLUSIONS: Gemcitabine plus cisplatin is an effective, well-tolerated regimen as a first-line treatment for recurrent/metastatic nasopharyngeal carcinoma.


Assuntos
Cisplatino/uso terapêutico , Desoxicitidina/análogos & derivados , Neoplasias Nasofaríngeas/tratamento farmacológico , Adulto , Idoso , Carcinoma , Desoxicitidina/uso terapêutico , Intervalo Livre de Doença , Esquema de Medicação , Quimioterapia Combinada , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas/mortalidade , Neoplasias Nasofaríngeas/patologia , Metástase Neoplásica , Recidiva Local de Neoplasia , Estadiamento de Neoplasias , Razão de Chances , Modelos de Riscos Proporcionais , Estudos Prospectivos , Análise de Sobrevida , Taiwan , Resultado do Tratamento , Gencitabina
20.
Nutr Cancer ; 66(7): 1211-9, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25256137

RESUMO

A small pilot study of the fermented soybean extract MicrSoy-20(MS-20) demonstrated its ability to restore chemotherapy-induced immunosuppression and improve quality of life (QoL). This randomized, cross-over, comparative trial was conducted to confirm the effects of MS-20 on QoL and to understand its underlying mechanism when used in conjunction with chemotherapy. One hundred forty-three patients undergoing cancer chemotherapy were randomly assigned to 2 groups. Group 1 was administered MS-20 for 1 wk followed by 3 wk of concomitant MS-20 plus chemotherapy. Group 2 was administered chemotherapy for 3 wk. QoL was assessed by the EORTC/QLQ-C30 questionnaire and visual analogue scales (VAS). Changes in immunological parameters and antioxidant profiles were also examined. Significant increases were observed in EORTC/QLQ-C30 scores for physical (4.45, P = 0.023) and social (3.99, P = 0.023) functioning in Group 1 patients compared to Group 2 patients. VAS scores for fatigue and appetite loss significantly improved with MS-20 treatment (P < 0.001). Group 1 patients exhibited smaller decreases in peripheral blood mononuclear cells compared to Group 2 patients (P = 0.026). Other immunological parameters, antioxidant, and safety profiles were not significantly different between treatment groups. Addition of MS-20 as an adjuvant to chemotherapy can be effective in improving QoL for cancer patients.


Assuntos
Apetite/efeitos dos fármacos , Fadiga/tratamento farmacológico , Neoplasias/tratamento farmacológico , Extratos Vegetais/farmacologia , Adulto , Idoso , Quimioterapia Adjuvante/métodos , Estudos Cross-Over , Determinação de Ponto Final , Fadiga/induzido quimicamente , Feminino , Humanos , Leucócitos Mononucleares , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Estudos Prospectivos , Qualidade de Vida , Glycine max/química , Inquéritos e Questionários , Escala Visual Analógica , Adulto Jovem
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