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1.
World J Gastroenterol ; 30(1): 112-114, 2024 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-38293328

RESUMO

This letter to the editor is a commentary on a study titled "Liver metastases: The role of magnetic resonance imaging." Exploring a noninvasive imaging evaluation system for the biological behavior of hepatocellular carcinoma (HCC) is the key to achieving precise diagnosis and treatment and improving prognosis. This review summarizes the role of magnetic resonance imaging in the detection and evaluation of liver metastases, describes its main imaging features, and focuses on the added value of the latest imaging tools (such as T1 weighted in phase imaging, T1 weighted out of phase imaging; diffusion-weighted imaging, T2 weighted imaging). In this study, I investigated the necessity and benefits of gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid for HCC diagnostic testing and prognostic evaluation.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Neoplasias Hepáticas/patologia , Carcinoma Hepatocelular/patologia , Meios de Contraste , Gadolínio DTPA , Imageamento por Ressonância Magnética/métodos , Imagem de Difusão por Ressonância Magnética , Estudos Retrospectivos
2.
Nat Commun ; 14(1): 1444, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36922495

RESUMO

With the advancement of global civilisation, monitoring and managing dumpsites have become essential parts of environmental governance in various countries. Dumpsite locations are difficult to obtain in a timely manner by local government agencies and environmental groups. The World Bank shows that governments need to spend massive labour and economic costs to collect illegal dumpsites to implement management. Here we show that applying novel deep convolutional networks to high-resolution satellite images can provide an effective, efficient, and low-cost method to detect dumpsites. In sampled areas of 28 cities around the world, our model detects nearly 1000 dumpsites that appeared around 2021. This approach reduces the investigation time by more than 96.8% compared with the manual method. With this novel and powerful methodology, it is now capable of analysing the relationship between dumpsites and various social attributes on a global scale, temporally and spatially.

3.
Materials (Basel) ; 15(21)2022 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-36363444

RESUMO

To study the effect of SAP incorporation on the early shrinkage of SAP internally cured concrete with the aim to solve the problems of early shrinkage and cracking of bridge leveling-layer concrete, using the SAP incorporation method as a parameter, the mechanical properties test of internally cured concrete, the shrinkage performance test of ring restraint and the scanning electron microscope observation test were carried out. The effects of the SAP content and incorporation method on the flowability, mechanical properties, shrinkage performance and microstructure of internally cured concrete were analyzed. The experimental results show that when the content of the SAP in concrete is 0.2% of the mass of cementitious materials, it has the least influence on the compressive strength of concrete. The addition of preabsorbed water to the SAP can delay early cement hydration, increase the later cement hydration rate and final hydration degree, and improve the concrete strength. Preabsorbed water mixed with an SAP can effectively improve the shrinkage of concrete, and the shrinkage reduction effect is more obvious than that from the dry addition of the SAP; the early cracking risk of concrete without an SAP is high, and it will crack before day 28. The addition of an SAP can strengthen the microstructure of concrete and improve its density and crack resistance, effectively avoiding concrete cracking. It is recommended that the water-absorbent resin be incorporated in a preabsorbent manner, and the SAP preabsorbent ratio is equal to the maximum water storage rate of the SAP.

4.
Comput Math Methods Med ; 2022: 1721526, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35535227

RESUMO

Whether TERT promoter mutation is related to more aggressive clinicopathologic features and worse outcomes in papillary thyroid carcinoma patients (PTCs) is still variable and controversial. Our intention was to investigate the risk or prognostic factors that may additionally predict the TERT promoter mutation doable of these lesions and new prevention techniques in PTCs. A total of 2,539 PTC patients with 11.50% TERT mutation have been analyzed using Revman 5.3 software in this study. The PubMed and Embase databases were systematically searched for works published until November 9, 2021. The following variables had been associated with an extended chance of TERT promoter mutation in PTC patients: age < 45 years (MD = 10.93, 95%CI = 7.25-14.61); gender = male (pooled OR = 1.63, 95%CI = 1.17-2.28); tumor size > 1 cm (MD = 0.56, 95%CI = 0.34-0.77); lymph node metastasis (pooled OR = 1.29, 95%CI = 0.93-1.79); vascular invasion (pooled OR = 1.78, 95%CI = 0.83-3.84); extrathyroidal extension (pooled OR = 2.00, 95%CI = 1.32-3.02); distant metastasis (pooled OR = 1.46, 95%CI = 1.04-2.04); advanced TNM stage (pooled OR = 3.19, 95%CI = 2.28-4.45). In addition, multifocality (pooled OR = 0.67, 95%CI = 0.14-3.24) had no affiliation with TERT promoter mutation in PTC patients. Our finding showed that age < 45 years, male, tumor size > 1 cm, lymph node metastasis, vascular invasion, and superior/advanced TNM stage were dangerous elements for TERT promoter mutation of worse effect in PTCs while that multifocality was once negatively correlated. TERT promoter mutation is drastically associated with recurrence and PTC-related mortality.


Assuntos
Telomerase , Câncer Papilífero da Tireoide , Humanos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Mutação , Prognóstico , Fatores de Risco , Telomerase/genética , Câncer Papilífero da Tireoide/genética , Câncer Papilífero da Tireoide/patologia
5.
J Clin Pharm Ther ; 46(4): 927-935, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34138497

RESUMO

WHAT IS KNOWN AND OBJECTIVE: Administration of corticosteroids to immune checkpoint inhibitors (ICI)-treated patients has raised concerns due to doubts about ICIs' efficacy under those conditions. Hence, we reviewed studies comparing overall and progression-free survival (OS and PFS) outcomes in patients with non-small-cell lung carcinoma (NSCLC) treated with ICI and either with or without corticosteroids for any reason. METHODS: We searched the PubMed Central, Cochrane library, EMBASE and MEDLINE databases from inception until February 2021 for relevant publications. We used the Newcastle-Ottawa scale to assess the quality of the identified studies. We used the published data to carry out a meta-analysis with a random-effects model and report pooled odds ratios (ORs) with 95% confidence intervals (CIs). RESULTS: We included data from 14 studies with 5461 participants in the meta-analysis. Most studies were retrospective in nature and of low quality, and most of them were conducted in the USA and in European countries. Nivolumab is the most common ICI used in the included studies followed by pembrolizumab. We found that patients using corticosteroids had reduced OSs (pooled HR, 1.82; 95% CI, 1.51-2.18) and PFSs (pooled HR, 1.69; 95% CI, 1.41-2.04) than the patients not using corticosteroids. We identified significant heterogeneity and publication bias for both the outcomes. However, the sensitivity analysis revealed that the estimates were robust to the individual study effects. WHAT IS NEW AND CONCLUSION: Our findings suggest that corticosteroids significantly reduce the OS and PFS of patients with NSCLC under ICI therapy. Hence, clinicians and oncologists should consider this information when prescribing corticosteroids for this target population.


Assuntos
Corticosteroides/uso terapêutico , Antineoplásicos Imunológicos/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Inibidores de Checkpoint Imunológico/uso terapêutico , Neoplasias Pulmonares/tratamento farmacológico , Corticosteroides/administração & dosagem , Antineoplásicos Imunológicos/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Humanos , Inibidores de Checkpoint Imunológico/administração & dosagem , Neoplasias Pulmonares/mortalidade , Estudos Observacionais como Assunto , Intervalo Livre de Progressão , Ensaios Clínicos Controlados Aleatórios como Assunto
6.
Pain Med ; 22(7): 1612-1618, 2021 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-33620466

RESUMO

OBJECTIVES: The treatment for neuropathic pain is still a big challenge. Pulsed radiofrequency technique has been widely used to relieve neuropathic pain in recent years. The purpose of this study is to optimize the temperature for pulsed radiofrequency therapy. DESIGN: Animal, experimental study. METHODS: Seventy-five male SD rats were randomly divided into five groups: Sham operation group (Sham group), chronic constriction injury group (CCI group), PRF 42°C group (P42 group), PRF 50°C group (P50 group), and PRF 60°C group (P60 group). The hindpaw withdrawal threshold (HWT), paw thermal withdrawal latency (PTWL), sciatic nerve structure, and the concentration of spinal methionine enkephalin(M-ENK) were detected to identify which temperature is the best for PRF treatment. RESULTS: PRF at 42°C, 50°C and 60°C significantly alleviated the pain in CCI rats. The therapeutic effects of 50°C and 60°C were similar, and both were better than 42°C. In addition, PRF using 42°C, 50°C, and 60°C mediated nerve injury to sciatic nerve were grade 1, 1, and 2, respectively. The concentration of M-ENK in spinal cord increased accompanying with the increasing of the temperature of PRF. CONCLUSIONS: PRF using 50°C could induce less damage while achieving better improvement of mechanical and thermal pain threshold than 42°C and 60°C in CCI rats, which may be achieved by promoting the expression of M-ENK in spinal cord.


Assuntos
Neuralgia , Tratamento por Radiofrequência Pulsada , Animais , Constrição , Masculino , Neuralgia/terapia , Ratos , Ratos Sprague-Dawley , Nervo Isquiático , Temperatura
7.
ACS Appl Mater Interfaces ; 11(21): 19066-19076, 2019 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-31066261

RESUMO

The acidity/alkalinity and structural properties of NiMgAl trimetallic oxides (MMOs) can be effectively modulated by the alkaline-etching process with various etching times, which are further used as a support to prepare KMoS-based catalysts through the cetyltrimethylammonium bromide-encapsulated Mo-precursor strategy. The enriched surface anion groups in alkaline-etched MMO affect the textural properties, metal-support interaction, and sulfidation degree of the as-synthesized KMoS-based catalysts. As a result, KMoS-based catalysts using alkaline-etched MMO as supports effectively enhance the reducibility and dispersion of Mo species, which exert a positive influence on higher alcohol synthesis (HAS) performance in CO hydrogenation. A proper balance between acidity/alkalinity and structural properties in K, Mo/MMO- x catalysts can significantly enhance the alcohol selectivity in HAS from 55 to 65% (carbon selectivity). The formation of C2+ alcohols can be boosted by adol condensation with optimal acidic/basic properties via suppressing the acidity and increasing the amount of basic sites. The alkaline-etching process also significantly improves the space time yield of C2+ alcohols over unit mass of molybdenum.

8.
Dalton Trans ; 47(46): 16567-16577, 2018 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-30417180

RESUMO

Metal-organic frameworks (MOFs), as precursors for synthesizing new carbon materials, hold promise for applications in the oxygen reduction reaction (ORR) as efficient non-precious metal catalysts. Here, a facile template-assisted strategy was adopted to fabricate a core-shell structure derived from MIL-101(Fe) and polyaniline. MIL-101(Fe) nanoparticles obtained by microwave-assisted synthesis were combined with PAni in different ratios and carbonized at 900 °C under flowing N2. An optimized core-shell Fe3O4/Fe3N@graphite carbon structure was successfully prepared and exhibited attractive ORR activity, with a half-wave potential of 0.916 V vs. RHE and an electron transfer number of 4.0 at 0.4 V vs. RHE. Furthermore, the catalyst displayed excellent stability in an alkaline solution. The superior ORR performance of the catalyst is mainly attributed to its stable core-shell structure, large specific surface area and high content of electrocatalytically active N species.

9.
Chemistry ; 24(70): 18689-18695, 2018 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-30318819

RESUMO

Electrochemical water splitting is a promising way for the sustainable production of hydrogen, but the efficiency of the overall water-splitting reaction largely depends on the oxygen evolution reaction (OER) because of its sluggish kinetics. Herein, a series of hierarchical ZnCo2 O4 /Co3 O4 /NC-CNT (NC-CNT=nitrogen-rich carbon nanotube) mesoporous dodecahedrons grafted to carbon nanotubes have been synthesized from ZnCo bimetallic zeolitic imidazolate frameworks (ZnCo-ZIFs) through sequential pyrolysis in nitrogen and mild oxidation in air. The simultaneous modulation of oxygen vacancies, composition, and hierarchical mesoporous architecture remarkably enhanced their electronic conduction and the amount and reactivity of accessible actives; thus boosting their intrinsic activity in the OER. The optimal ZnCo2 O4 /Co3 O4 /NC-CNT-700 sample exhibited a large current density of 50 mA cm-2 at a potential of 1.65 V, a small Tafel slope of 88.5 mV dec-1 , and superior stability in alkaline media. This work should provide a facile strategy for the rational design of advanced OER catalysts by simultaneous engineering of oxygen vacancies and composition.

10.
Dalton Trans ; 47(24): 7975-7982, 2018 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-29863208

RESUMO

Despite intense research in the past decades, the lack of high-performance catalysts for fuel cell reactions remains a challenge in realizing fuel cell applications. Herein, we report a novel hybrid nanomaterial of platinum-nickel hydroxide-nanotubes (Pt/Ni(OH)2/CNTs) for improving electrocatalytic performance in alkaline environments. Ni(OH)2 was directly grown on functionalized nanotubes and then, Pt nanoparticles were in situ immobilized by the microwave synthesis method. Due to electronic and synergistic effects, 10 : 2-Pt/Ni(OH)2/N-CNT catalyst exhibited 2.77 times specific activity and 6.27 times mass activity toward methanol oxidation reaction (MOR), which were higher than those of commercial Pt/C in alkaline solution. The CO-stripping experiments and hydrogen evolution reaction (HER) further demonstrated that Ni(OH)2 could promote oxidation removal of carbonaceous poison for MOR via accelerating water dissociation: (i) Ni(OH)2 acted on an H2O molecule, leading to the formation of OHad; (ii) OHad oxidized the intermediate COad to CO2. Furthermore, the 10 : 2-Pt/Ni(OH)2/N-CNT catalyst also exhibited 2.07 times specific activity and 1.67 times mass activity toward oxygen reduction reaction (ORR), which were higher than those of commercial Pt/C in alkaline solution and Pt/N-CNT catalysts. Thus, the preparation of this hybrid nanomaterial provides a new direction for catalyst performance optimization towards next-generation fuel cells in alkaline environments.

11.
Small ; 13(46)2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-29044959

RESUMO

Synthesizing noble metallic nanoparticles (NPs) enclosed by high-index facets (HIFs) is challenged as it involves the tuning of growth kinetics, the selective adsorption of certain chemical species, and the epitaxial growth from HIF enclosed seeds. Herein, a simple and general strategy is reported by using dual reduction agents and dual capping agents to prepare Pt-based alloy NPs with HIFs, in which both glycine and poly(vinylpyrrolidone) serve as the reductants and capping agents. Due to the facilely tunable growth/nucleation rates and protecting abilities of the reductants and capping agents, Pt concave nanocube (CNC), binary Pt-Ni CNC, ternary Pt-Mn-Cu CNC, and Pt-Mn-Cu ramiform polyhedron alloy NPs terminated by HIFs as well as other NPs with well-defined morphologies such as Pt-Mn-Cu nanocube and Pt-Mn-Cu nanoflower are obtained with this approach. Owing to the high density of low-coordinated Pt sites (HIF structure) and the unique electronic effect of Pt-Mn-Cu ternary alloys, the as-prepared Pt-Mn-Cu NPs show enhanced catalytic activity toward methanol and formic acid electro-oxidation reactions with excellent stability. This work provides a promising methodology for designing and fabricating Pt-based alloy NPs as efficient fuel cell catalyst.

12.
ACS Appl Mater Interfaces ; 8(50): 34396-34404, 2016 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-27935299

RESUMO

Hydrogen produced from electrocatalytic water splitting is a promising route due to the sustainable powers derived from the solar and wind energy. However, the sluggish kinetics at the anode for water splitting makes the highly effective and inexpensive electrocatalysts desirable in oxygen evolution reaction (OER) by structure and composition modulations. Metal-organic frameworks (MOFs) have been intensively used as the templates/precursors to synthesize complex hollow structures for various energy-related applications. Herein, an effective and facile template-engaged strategy originated from bimetal MOFs is developed to construct hollow microcubes assembled by interconnected nanopolyhedron, consisting of intimately dominant FeNi alloys coupled with a small NiFe2O4 oxide, which was confined within carbonitride outer shell (denoted as FeNi/NiFe2O4@NC) via one-step annealing treatment. The optimized FeNi/NiFe2O4@NC exhibits excellent electrocatalytic performances toward OER in alkaline media, showing 10 mA·cm-2 at η = 316 mV, lower Tafel slope (60 mV·dec-1), and excellent durability without decay after 5000 CV cycles, which also surpasses the IrO2 catalyst and most of non-noble catalysts in the OER, demonstrating a great perspective. The superior OER performance is ascribed to the hollow interior for fast mass transport, in situ formed strong coupling between FeNi alloys and NiFe2O4 for electron transfer, and the protection of carbonitride layers for long stability.

13.
Drug Deliv ; 22(5): 627-37, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-24471983

RESUMO

CONTEXT: Pathogen evolution currently outpaces novel drug development, and because development of new antibiotics is pending, combination therapy with existing drugs may provide effective alternative treatments. OBJECTIVE: The present study was aimed at evaluating the concurrent use of two antibiotics, daptomycin and clarithromycin, against methicillin-resistant Staphylococcus aureus (MRSA) infections. MATERIALS AND METHODS: Polyeythylene glycol (PEGylated liposomes loaded with daptomycin, clarithromycin, or both (PL[CD]) at an optimized mass ratio of 1:32 were generated and characterized using dynamic light scattering and electron microscopy. In vitro and in vivo approaches were used to compare liposome effects on MRSA. RESULTS: PL[CD] were stable, with a mean (± SD) vesicle diameter of 98.2 ± 2.21 nm and encapsulation efficiency of 94.71 ± 1.37% (daptomycin) and 92.94 ± 1.21% (clarithromycin). Compared with daptomycin-only liposomes, PL[CD] showed significantly enhanced anti-MRSA activity in vitro and significantly reduced MRSA bacterial load and increased host survival in vivo. DISCUSSION: Co-delivery of daptomycin with clarithromycin produced significant anti-MRSA activity in the presence of only one-thirtieth of the concentration required in liposomes containing daptomycin only. CONCLUSION: These findings suggested that concurrent liposomal delivery of daptomycin and clarithromycin has the potential to be an effective and less toxic treatment for MRSA infections.


Assuntos
Antibacterianos/farmacologia , Claritromicina/farmacologia , Daptomicina/farmacologia , Lipossomos/farmacologia , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Polietilenoglicóis/farmacologia , Animais , Antibacterianos/administração & dosagem , Cromatografia Líquida de Alta Pressão , Claritromicina/administração & dosagem , Daptomicina/administração & dosagem , Modelos Animais de Doenças , Lipossomos/uso terapêutico , Camundongos , Polietilenoglicóis/uso terapêutico , Infecções Estafilocócicas/tratamento farmacológico , Resultado do Tratamento
14.
Yao Xue Xue Bao ; 49(5): 701-10, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-25151744

RESUMO

In the face of escalating problems with pathogen control, the development of proper formulations of existing antibiotics is as important as the development of novel antibiotics. Daptomycin is a lipopeptide antibiotic with potent activity against Gram-positive bacteria. Currently, only injectable solution of daptomycin has been approved for clinical use. In the present study, the formulation of PEGylated liposomal daptomycin (PLD) was prepared and optimized, and its efficacy against methicillin-resistant Staphylococcus aureus (MRSA252) strains was investigated. The obtained PLD had a mean vesicle diameter of (111.5 +/- 15.4) nm and a mean percent drug loading of (5.81 +/- 0.19) % with high storage stability. Potent activity of PLD against MRSA was demonstrated in vitro with a more sustained effect than that of conventional liposomal daptomycin and daptomycin solution. In addition, intravenous administration of a single dose (equal to human use) of PLD significantly increased the survival of mice in a MRSA252 systemic infection model compared with other formulations. Drug distribution in the lung was significantly enhanced following administration of PLD, and no measurable tissue lesions or pathological changes were detected during PLD treatment. Taken together, PEGylated liposomes loaded with daptomycin may represent a promising approach to reduce MRSA252 infections, especially those involving bloodstream dissemination, such as hematogenous pulmonary infection.


Assuntos
Antibacterianos/farmacologia , Daptomicina/farmacologia , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Infecções Estafilocócicas/tratamento farmacológico , Animais , Lipossomos , Camundongos
15.
Yao Xue Xue Bao ; 49(1): 106-14, 2014 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-24783515

RESUMO

In this study, we developed a novel liposome-silica hybrid nano-carrier for tumor combination therapy via oral route, using paclitaxel and cyclosporine as a model drug pair. Optimization of the preparation of the drug-loading formulation and characterization of its physicochemical parameters and drug release profile were performed in vitro. Then in vivo pharmacodynamics and pharmacokinetics studies were performed. The results showed that the obtained formulation has a small particle size (mean diameter of 100.2 +/- 15.2 nm), a homogeneous distribution [the polydispersity index was (0.251 +/- 0.018)] and high encapsulation efficiency (90.15 +/- 2.47) % and (80.64 +/- 3.52) % for paclitaxel and cyclosporine respectively with a mild and easy preparation process. A sequential drug release trend of cyclosporine prior to palictaxel was observed. The liposome-silica hybrid nano-carrier showed good biocompatibility in vivo and co-delivery of cyclosporine and paclitaxel significantly enhanced the oral absorption of paclitaxel with improved anti-tumor efficacy, suggesting a promising approach for multi-drug therapy against tumor and other serious diseases via oral route.


Assuntos
Ciclosporina/administração & dosagem , Portadores de Fármacos/química , Lipossomos/química , Nanopartículas , Paclitaxel/administração & dosagem , Dióxido de Silício/química , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/antagonistas & inibidores , Administração Oral , Animais , Antineoplásicos Fitogênicos/administração & dosagem , Antineoplásicos Fitogênicos/farmacocinética , Antineoplásicos Fitogênicos/farmacologia , Disponibilidade Biológica , Ciclosporina/farmacocinética , Ciclosporina/farmacologia , Feminino , Masculino , Camundongos , Transplante de Neoplasias , Paclitaxel/farmacocinética , Paclitaxel/farmacologia , Tamanho da Partícula , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Sarcoma 180/patologia , Carga Tumoral/efeitos dos fármacos
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