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1.
Langmuir ; 40(21): 11251-11262, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38748644

RESUMO

Artificial photosynthesis for high-value hydrogen peroxide (H2O2) through a two-electron reduction reaction is a green and sustainable strategy. However, the development of highly active H2O2 photocatalysts is impeded by severe carrier recombination, ineffective active sites, and low surface reaction efficiency. We developed a dual optimization strategy to load dense Ni nanoparticles onto ultrathin porous graphitic carbon nitride (Ni-UPGCN). In the absence and presence of sacrificial agents, Ni-UPGCN achieved H2O2 production rates of 169 and 4116 µmol g-1 h-1 with AQY (apparent quantum efficiency) at 420 nm of 3.14% and 17.71%. Forming a Schottky junction, the surface-modified Ni nanoparticles broaden the light absorption boundary and facilitate charge separation, which act as active sites, promoting O2 adsorption and reducing the formation energy of *OOH (reaction intermediate). This results in a substantial improvement in both H2O2 generation activity and selectivity. The Schottky junction of dual modulation strategy provides novel insights into the advancement of highly effective photocatalytic agents for the photosynthesis of H2O2.

2.
Nutr Cancer ; 75(3): 805-814, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36533716

RESUMO

Determine the association of lean body mass (LBM) on the incidence and severity of peripheral neurotoxicity in cancer patients who received nab-paclitaxel alone or combined with cisplatin or carboplatin. This prospective clinical study examined 32 cancer patients classified into a sarcopenia or non-sarcopenia group according to the Asian L3 vertebra skeletal muscle index (L3-SMI) at Ordos Central Hospital (China) from December 2020-2021, to compare the incidence and severity of neurotoxicity and analizing the relationship between nab-paclitaxel dose per kg LBM and neurotoxicity. There were 18 patients (56.25%) in the sarcopenia group and 14 (43.75%) in the non-sarcopenia group. The incidences of peripheral and severe neurotoxicity were higher in the sarcopenia group (both P < 0.05). Patients in three different body surface area (BSA) groups received the same nab-paclitaxel dose (260 mg/m2 BSA). However, when patients were divided into three groups according to LBM, they received different doses (low-LBM: 15.18 mg/kg LBM, middle-LBM: 12.82 mg/kg LBM, and high-LBM: 11.14 mg/kg LBM). The incidence of grade-C or higher neurotoxicity of these three groups was 61.54% (8/13), 20.00% (1/5), and 11.11% (1/9). Sarcopenia and a higher dose of nab-paclitaxel per kg LBM were associated with peripheral and severe neurotoxicity. Chemotherapy dosing based on body composition may reduce neurotoxicity in patients receiving nab-paclitaxel.Registration number of Clinical Trial: ChiCTR2000040918.


Assuntos
Neoplasias , Sarcopenia , Humanos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Composição Corporal , Neoplasias/complicações , Neoplasias/tratamento farmacológico , Paclitaxel/efeitos adversos , Estudos Prospectivos , Sarcopenia/induzido quimicamente , Sarcopenia/epidemiologia
3.
Int J Mol Sci ; 23(24)2022 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-36555570

RESUMO

Surface-enhanced Raman spectroscopy (SERS) is an ultra-sensitive and rapid technique that is able to significantly enhance the Raman signals of analytes absorbed on functional substrates by orders of magnitude. Recently, semiconductor-based SERS substrates have shown rapid progress due to their great cost-effectiveness, stability and biocompatibility. In this work, three types of faceted Co3O4 microcrystals with dominantly exposed {100} facets, {111} facets and co-exposed {100}-{111} facets (denoted as C-100, C-111 and C-both, respectively) are utilized as SERS substrates to detect the rhodamine 6G (R6G) molecule and nucleic acids (adenine and cytosine). C-100 exhibited the highest SERS sensitivity among these samples, and the lowest detection limits (LODs) to R6G and adenine can reach 10-7 M. First-principles density functional theory (DFT) simulations further unveiled a stronger photoinduced charge transfer (PICT) in C-100 than in C-111. This work provides new insights into the facet-dependent SERS for semiconductor materials.


Assuntos
Nanopartículas Metálicas , Nanopartículas Metálicas/química , Análise Espectral Raman/métodos , Semicondutores
4.
Molecules ; 27(12)2022 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-35744947

RESUMO

The main aspects of material research: material synthesis, material structure, and material properties, are interrelated. Acquiring atomic structure information of electron beam sensitive materials by electron microscope, such as porous zeolites, organic-inorganic hybrid perovskites, metal-organic frameworks, is an important and challenging task. The difficulties in characterization of the structures will inevitably limit the optimization of their synthesis methods and further improve their performance. The emergence of integrated differential phase contrast scanning transmission electron microscopy (iDPC-STEM), a STEM characterization technique capable of obtaining images with high signal-to-noise ratio under lower doses, has made great breakthroughs in the atomic structure characterization of these materials. This article reviews the developments and applications of iDPC-STEM in electron beam sensitive materials, and provides an outlook on its capabilities and development.


Assuntos
Elétrons , Microscopia Eletrônica de Transmissão e Varredura/métodos , Microscopia de Contraste de Fase
5.
Molecules ; 27(17)2022 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-36080302

RESUMO

As a promising metal-free photocatalyst, graphitic carbon nitride (g-C3N4) is still limited by insufficient visible light absorption and rapid recombination of photogenerated carriers, resulting in low photocatalytic activity. Here, we adjusted the microstructure of the pristine bulk-g-C3N4 (PCN) and further loaded silver (Ag) nanoparticles. Abundant Ag nanoparticles were grown on the thin-layer g-C3N4 nanosheets (CNNS), and the Ag nanoparticles decorated g-C3N4 nanosheets (Ag@CNNS) were successfully synthesized. The thin-layer nanosheet-like structure was not only beneficial for the loading of Ag nanoparticles but also for the adsorption and activation of reactants via exposing more active sites. Moreover, the surface plasmon resonance (SPR) effect induced by Ag nanoparticles enhanced the absorption of visible light by narrowing the band gap of the substrate. Meanwhile, the composite band structure effectively promoted the separation and transfer of carriers. Benefiting from these merits, the Ag@CNNS reached a superior hydrogen peroxide (H2O2) yield of 120.53 µmol/g/h under visible light irradiation in pure water (about 8.0 times higher than that of PCN), significantly surpassing most previous reports. The design method of manipulating the microstructure of the catalyst combined with the modification of metal nanoparticles provides a new idea for the rational development and application of efficient photocatalysts.

6.
Food Chem ; 411: 135483, 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-36708641

RESUMO

Formaldehyde (FA) is widely used as an adhesion promoter and dyeing aid in industrial production. Ingestion of a certain amount of formaldehyde may cause corrosive burns in the mouth, throat, and digestive tract. Therefore, it is very necessary to use simple and effective detection methods to ensure human health and food safety. Herein, a novel fluorescent probe NFD based on naphthalimide for the detection of formaldehyde in food was designed and synthesized. The probe had a remarkable fluorescence response to formaldehyde at 554 nm. And it exhibited fascinating advantages of good selectivity, high sensitivity, and low detection limit. In addition, the solid sensor prepared by loading the probe on the filter paper was successfully realized the visual detection of liquid and gaseous formaldehyde. More importantly, the probe possessed excellent stability in the detection of formaldehyde in real food samples and animal serum samples.


Assuntos
Corantes Fluorescentes , Gases , Animais , Humanos , Espectrometria de Fluorescência/métodos , Formaldeído , Naftalimidas
7.
Nat Commun ; 14(1): 7115, 2023 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-37932292

RESUMO

Photocatalytic two-electron oxygen reduction to produce high-value hydrogen peroxide (H2O2) is gaining popularity as a promising avenue of research. However, structural evolution mechanisms of catalytically active sites in the entire photosynthetic H2O2 system remains unclear and seriously hinders the development of highly-active and stable H2O2 photocatalysts. Herein, we report a high-loading Ni single-atom photocatalyst for efficient H2O2 synthesis in pure water, achieving an apparent quantum yield of 10.9% at 420 nm and a solar-to-chemical conversion efficiency of 0.82%. Importantly, using in situ synchrotron X-ray absorption spectroscopy and Raman spectroscopy we directly observe that initial Ni-N3 sites dynamically transform into high-valent O1-Ni-N2 sites after O2 adsorption and further evolve to form a key *OOH intermediate before finally forming HOO-Ni-N2. Theoretical calculations and experiments further reveal that the evolution of the active sites structure reduces the formation energy barrier of *OOH and suppresses the O=O bond dissociation, leading to improved H2O2 production activity and selectivity.

8.
Front Oncol ; 12: 965848, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36523983

RESUMO

Objective: To explore the dynamic changes in the body composition during chemotherapy in patients with gastrointestinal malignancies in the context of active nutrition intervention. Methods: Patients with gastrointestinal malignancies receiving first-line chemotherapy in the Department of Medical Oncology of Ordos Central Hospital from September 2019 to January 2022 were included in this study. The Nutritional Risk Screening form 2002, Patient-Generated Subjective Global Assessment form, bioelectrical impedance analysis, and dynamic changes in L3 skeletal muscle index (SMI) (L3SMI) were assessed at baseline and after chemotherapy. The recommended protocol of the Nutrition Guidelines for Cancer Patients in China 2020 was adopted as the active nutrition intervention. Chemotherapy-related toxic adverse reactions and the degree of toxicity were recorded with the adoption of the Common Terminology Criteria for Adverse Events version 4.0 by the National Institutes of Health. The type of toxicity Chemotherapy-Induced Nauseaand Vomiting(CINV) and hematological. Results: Fifty cases were enrolled in the study, and 38 cases completed the dynamic follow-ups. The average follow-up time was 125.63 d. In the context of active nutrition intervention, the prevalence of sarcopenia decreased from 26.3% before chemotherapy to 21.1% after chemotherapy. The average L3SMI decreased from 38.77 cm2/m2 to 38.04 cm2/m2, with a reduction of 1.41% ± 8.49% (P = 0.177). The SMI remained stable or increased in 57.9% (22/38) of patients. The benefit of active nutrition intervention was greater in the sarcopenic group than in the non-sarcopenic group (P = 0.033). There was an increased incidence of chemotherapy-related toxic adverse reactions of ≥ grade 3 during chemotherapy in the sarcopenic group compared with the muscle retention/gain group (P = 0.089). Conclusion: Active nutrition intervention might decrease the degree of reduction of L3SMI and the incidence of sarcopenia in patients with gastrointestinal tumors and raise the proportion of patients with stable or increased SMI during chemotherapy.

9.
Zhonghua Wei Zhong Bing Ji Jiu Yi Xue ; 31(4): 509-512, 2019 Apr.
Artigo em Zh | MEDLINE | ID: mdl-31109433

RESUMO

OBJECTIVE: The modified early warning score (MEWS), as a rapid assessment and early warning scoring tool, has been widely used in patients in China, which can help nurses to identify potentially critical patients early, but not in all clinical fields. Through the retrieval of the relevant literature of the clinical application of the MEWS in Wanfang Medical Database from 2011 to 2018, the SWOT analysis was used in this paper [strength (S), weakness (W), opportunities (O) and threats (T)] methods, to systematically analyze the advantages, problems existence, implementation opportunities and challenges in the clinical application of the MEWS in our country. The purpose of this study was to obtain the best cut-off value of MEWS in different diseases and to formulate standard early-warning intervention measures for MEWS, which may provide reference for clinical workers to carry out relevant research.


Assuntos
Estado Terminal , Diagnóstico Precoce , Monitorização Fisiológica/métodos , China , Estado Terminal/enfermagem , Humanos , Diagnóstico de Enfermagem , Valores de Referência
10.
Curr Probl Cancer ; 43(6): 100462, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-30709557

RESUMO

OBJECTIVE: To assess the safety and efficacy of combined neurokinin-1 antagonist aprepitant treatment for multiple-day anthracycline chemotherapy-induced nausea and vomiting. METHODS: One hundred patients with breast cancer from department of Medical Oncology of Ordos Central Hospital from June 2015 to February 2018 were selected and randomize subdivided into 2 groups. All cases received anthracycline (30 mg/m2/d for pirarubicin or 45 mg/m2/d for epirubicin) and cyclophosphamide adjuvant chemotherapy, along with either the standard therapy (dexamethasone and tropisetron) or the combined aprepitant therapy (aprepitant plus dexamethasone and tropisetron). The results of the observation between groups were presented by complete response in the overall phase (OP, 0-120 hours), acute phase (AP, 0-24 hours) and delay phase (DP, 25-120 hours). The Kaplan-Meier curves were plotted to exhibit the first time of vomiting, Functional Living Index-Emesis of patients' quality of life, and therapy-related adverse effects (AEs). RESULTS: The complete response of OP, AP, and DP were statistically different between aprepitant group and standard group (80.0% vs 48%, P = 0.001; 92.0% vs 74%, P = 0.017; 80.0% vs 48%, P = 0.001). The aprepitant group held a longer time reaching the first emesis after the relevant treatment than the standard group. The Functional Living Index-Emesis increased significantly in the aprepitant group compared with the standard group (24% vs 8.3%, P = 0.029). Fatigue and constipation were the only AEs of aprepitant, since no significant differences were observed in fatigue between the 2 groups (72% vs 70%, P = 0.826), while the incidence of constipation of aprepitant group was higher than the standard group (48% vs 28%, P = 0.039). CONCLUSION: Combined aprepitant therapy is efficient and safe in the multiple-day anthracycline chemotherapy-induced nausea and vomiting control and is recommended for the clinical use.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Aprepitanto/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Náusea/tratamento farmacológico , Antagonistas dos Receptores de Neurocinina-1/uso terapêutico , Vômito/tratamento farmacológico , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Estudos de Casos e Controles , Doxorrubicina/administração & dosagem , Doxorrubicina/análogos & derivados , Epirubicina/administração & dosagem , Feminino , Seguimentos , Humanos , Pessoa de Meia-Idade , Náusea/induzido quimicamente , Náusea/patologia , Prognóstico , Estudos Prospectivos , Taxa de Sobrevida , Vômito/induzido quimicamente , Vômito/patologia
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