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1.
Inorg Chem ; 63(30): 14171-14182, 2024 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-39001852

RESUMO

Highly efficient removal of low concentrations of hydrogen isotope gas in air is crucial for the safe operation of nuclear energy plants. Herein, silicalite-1-confined Pt cluster catalysts were used for the catalytic oxidation of hydrogen isotopes, and the related catalytic mechanism was revealed. Increased temperature in direct hydrogen reduction treatment slightly increased the size of Pt clusters from 1.6 nm at 400 °C to 1.8 nm at 600 °C. The catalyst reduced at 600 °C exhibited excellent performance (99%) in hydrogen isotope oxidation at 75 °C, as well as high stability and catalytic efficiency in continuous and intermittent operation for 7200 min. X-ray absorbance spectroscopy confirmed the existence of Pt clusters in the catalysts, and the theoretical results showed that the total net charge was -0.07 e, indicating a slight charge transfer from the zeolite to the Pt atoms. The metal-support interaction thermally stabilized Pt clusters and altered the metal electronic structure, which enhanced the catalytic activity following a hydroperoxyl (OOH)-mediated route. Based on the low reaction temperature, efficient hydrogen conversion rate, and high stability, the silicalite-1-confined Pt cluster catalyst is expected to be used in hydrogen isotope oxidation treatment to achieve nuclear safety.

2.
J Environ Manage ; 324: 116342, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36166870

RESUMO

In order to find a rapid, efficient, safe and reliable treatment technology for radioactive contaminated soil, the microwave sintering method was used to sinter the simulated radioactive contaminated soil with different CeO2 content at 1100 °C, 1200 °C and 1300 °C for 30 min to achieve vitrification. The phase, microstructure, morphology, mechanical properties, and chemical durability of the sintered samples were investigated. XRD and SEM-EDS results showed that Ce4+ did not participate in the formation of the glass network, but was fixed in the glass network structure. The amorphous fraction of the samples sintered at 1300 °C can reach up to 98%. EDS results showed that the element distribution was uniform. In addition, the density and hardness values of the sintered matrices were in the range of 1.875-2.543 g/cm3 and 6.667-7.112 GPa, respectively. Our results show that the density and hardness values are related to the sintering temperature and CeO2 content. The normalized leaching rate of Ce in samples reached 10-7 g/(m2·d) after 28 d.


Assuntos
Vidro , Micro-Ondas , Temperatura , Teste de Materiais , Solo
3.
J Biochem Mol Toxicol ; 35(4): e22699, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33398916

RESUMO

Statins are a group of hydroxymethylglutaryl coenzyme A reductase inhibitors that are used in the treatment of cardiovascular diseases. However, statins have been found to be cytotoxic, and many unexpected side effects have been reported in clinical applications. The susceptibilities of different cell lines toward statins are diverse, and the mechanisms of cytotoxicity remain unknown. Therefore, the present study aimed to investigate differences in the susceptibility to and mechanisms of statin-induced cytotoxicity in two cell lines, HT-29 and A549, using a high content screening-based multiparametric toxicity assay panel. We found that the two cell types exhibited differing susceptibilities to the cytotoxic effects of the different statins. Additionally, the cytotoxicity was inconsistent between different statins in the two cell lines. Four statins with strong cytotoxicity decreased the viability of HT-29 cells via the mitochondrial pathway, as evidenced by decreased mitochondrial membrane potential, and elevated mitochondrial mass, calcium release and cell apoptosis, and reactive oxygen species. In contrast, these four statins only induced a decrease in the mitochondrial membrane potential in A549 cells. The above results provide an objective reason for future evaluations of cytotoxic differences in cell types and the underlying mechanisms of cytotoxicity in different statins, and provide a good scientific basis for further research on countermeasures against statin-induced cell injuries.


Assuntos
Apoptose/efeitos dos fármacos , Citotoxinas/efeitos adversos , Inibidores de Hidroximetilglutaril-CoA Redutases/efeitos adversos , Potenciais da Membrana/efeitos dos fármacos , Mitocôndrias/metabolismo , Células A549 , Sobrevivência Celular/efeitos dos fármacos , Citotoxinas/farmacologia , Células HT29 , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Mitocôndrias/patologia
4.
J Enzyme Inhib Med Chem ; 36(1): 1079-1087, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34030574

RESUMO

Inhibitors of COMT are clinically used for the treatment of Parkinson's disease. Here, we report the first natural pentacyclic triterpenoid-type COMT inhibitors and their structure-activity relationships and inhibition mechanism. The most potent compounds were found to be oleanic acid, betulinic acid and celastrol with IC50 values of 3.89-5.07 µM, that acted as mixed (uncompetitive plus non-competitive) inhibitors of COMT, representing a new skeleton of COMT inhibitor. Molecular docking suggested that they can specifically recognise and bind with the unique hydrophobic residues surrounding the catechol pocket. Furthermore, oleanic acid and betulinic acid proved to be less disruptive of mitochondrial membrane potential (MMP) compared to tolcapone, thus reducing the risk of liver toxicity. These findings could be used to produce an ideal lead compound and to guide synthetic efforts in generating related derivatives for further preclinical testing.


Assuntos
Produtos Biológicos/farmacologia , Catecol O-Metiltransferase/metabolismo , Inibidores Enzimáticos/farmacologia , Triterpenos Pentacíclicos/farmacologia , Produtos Biológicos/síntese química , Produtos Biológicos/química , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Humanos , Cinética , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Conformação Molecular , Simulação de Acoplamento Molecular , Triterpenos Pentacíclicos/síntese química , Triterpenos Pentacíclicos/química , Proteínas Recombinantes/metabolismo , Estereoisomerismo , Relação Estrutura-Atividade
5.
Front Pharmacol ; 15: 1380098, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38881875

RESUMO

Rheumatoid arthritis is a chronic immunological disease leading to the progressive bone and joint destruction. Angiogenesis, accompanied by synovial hyperplasia and inflammation underlies joint destruction. Delaying or even blocking synovial angiogenesis has emerged as an important target of RA treatment. Natural medicines has a long history of treating RA, and numerous reports have suggested that natural medicines have a strong inhibitory activity on synovial angiogenesis, thereby improving the progression of RA. Natural medicines could regulate the following signaling pathways: HIF/VEGF/ANG, PI3K/Akt pathway, MAPKs pathway, NF-κB pathway, PPARγ pathway, JAK2/STAT3 pathway, etc., thereby inhibiting angiogenesis. Tripterygium wilfordii Hook. f. (TwHF), sinomenine, and total glucoside of Paeonia lactiflora Pall. Are currently the most representative of all natural products worthy of development and utilization. In this paper, the main factors affecting angiogenesis were discussed and different types of natural medicines that inhibit angiogenesis were systematically summarized. Their specific anti-angiogenesis mechanisms are also reviewed which aiming to provide new perspective and options for the management of RA by targeting angiogenesis.

6.
J Glob Health ; 14: 04058, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38602274

RESUMO

Background: Due to a lack of related research, we aimed to determine the effectiveness of a pharmacist-led medication reconciliation intervention in China. Methods: We conducted a multicentre, prospective, open-label, assessor-blinded, cluster, nonrandomised controlled study at six county-level hospitals, with hospital wards serving as the clusters. We included patients discharged from the sampled hospitals who were aged ≥60 years; had ≥1 studied diagnoses; and were prescribed with ≥3 medications at discharge. Patients in the intervention group received a pharmacist-led medication reconciliation intervention and those in the control group received standard care. We assessed the incidence of medication discrepancies at discharge, patients' medication adherence, and health care utilisation within 30 days after discharge. Results: There were 429 patients in the intervention group (mean age = 72.5 years, standard deviation (SD) = 7.0) and 526 patients in the control group (mean age = 73.6 years, SD = 7.1). Of the 1632 medication discrepancies identified at discharge, fewer occurred in the intervention group (1.9 per patient on average) than the control group (2.6 per patient on average).The intervention significantly reduced the incidence of medication discrepancy by 9.6% (95% confidence interval (CI) = -15.6, -3.6, P = 0.002) and improved patients' medication adherence, with an absolute decrease in the mean adherence score of 2.5 (95% CI = -2.8, -2.2, P < 0.001). There was no significant difference in readmission rates between the intervention and control groups. Conclusions: Pharmacist-led medication reconciliation at discharge from Chinese county-level hospitals reduced medication discrepancies and improved patients' adherence among patients aged 60 years or above, though no impact on readmission after discharge was observed. Registration: ChiCTR2100045668.


Assuntos
Reconciliação de Medicamentos , Farmacêuticos , Humanos , Idoso , Estudos Prospectivos , Hospitais de Condado , Adesão à Medicação
7.
Biomed Pharmacother ; 167: 115550, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37741254

RESUMO

Corydalis bungeana Turcz. (CBT) is frequently used to treat inflammatory illnesses, the mechanisms underlying its use to ulcerative colitis (UC) remain unclear. A dextran sulfate sodium (DSS)-induced UC mice model was established. The disease activity index (DAI), colonic length, histological inspection by hematoxylin-eosin staining, the cytokines levels in the colon, proteomics and intestinal flora in mice were investigated to evaluate the effect of CBT. The results showed that CBT can significantly reduce the DAI, increase the length of colon, improve the pathological injury of colon tissue, decrease the level of TNF-α, IL-6, IL-1ß and increase the level of IL-10 in UC mice. Gut microbe sequencing showed that CBT could enhance the abundance of the intestinal microbiome, decrease possibly harmful bacteria and promote potentially helpful microbes. Proteomics investigation showed that 20 overlapping differentially expressed proteins (DEPs) were discovered in the control, model, and CBT administration groups. The DEPs in the CBT administration group were connected to biological procedures mainly involving detoxification. Extracellular matrix (ECM) receptor-associated proteins such as Col6a1 and CD36 may be important targets for CBT treatment of UC. Overall, this integrated methodology identified a comprehensive multi-omics network, composed of a certain set of gut microbiota and proteins, which may be potential targets for CBT treatment with UC.

8.
Appl Radiat Isot ; 200: 110960, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37515858

RESUMO

The evaluation of radiation resistance of the treated radioactive contaminated soil is crucial. The irradiation behavior of simulated radioactive soil waste irradiated with 1.5 MeV Xe20+ ions at fluences of 1 × 1012-1 × 1015 ions/cm2 was studied. Before the irradiation experiment, all the samples were sintered by microwave. The results showed that microwave sintering may be used to treat radioactive contaminated soil. In addition, the irradiation experiment results show that when the Nd2O3 content was low (<20 wt.%), the irradiation has little effect on the sample. When the Nd2O3 content was higher, the Vickers hardness of the sample (25 wt.%) decreased by 7 % at a fluence of 1 × 1015 ions/cm2, which may be due to the high Nd2O3 content that destroyed the overall stability of the glass waste form. The low normalized leaching rate of the irradiated sample (LRNd, ∼10-6 g·m-2·d-1) also proved that it had good aqueous durability. Moreover, the radiation resistance of the sample was illustrated by studying the influence mechanism of 1.5 MeV Xe20+ irradiation on radioactive contaminated soil. This work can help to study the environmental pollution problems of radioactive contaminated soil containing various contents of actinide nuclear waste.

9.
BMJ Open ; 12(3): e053741, 2022 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-35277404

RESUMO

INTRODUCTION: Pharmacist-participated medication reconciliation proved an effective strategy to decrease the risk of medication discrepancy-related errors. However, it is still under pilot in China and its effectiveness in the Chinese healthcare system remains unclear. This study aims to conduct a pharmacist-participated medication reconciliation intervention for elderly patients in county hospitals in China and to evaluate its effect. METHODS AND ANALYSIS: This is a multicentre, prospective, open-label, assessor-blinded, cluster, non-randomised, controlled study for elderly patients. The study will be conducted in seven county hospitals, and the clusters will be hospital wards. In each hospital, two internal medicine wards will be randomly allocated into either intervention group or control group. Patients in the intervention group will receive pharmacist-participated medication reconciliation, and those in the control group will receive standard care. The primary outcome is the incidence of medication discrepancy, and the secondary outcomes are patients' medication adherence, healthcare utilisation and medical costs within 30 days after discharge. ETHICS AND DISSEMINATION: Ethics committee approval of this study was obtained from Peking University Institution Review Board (IRB00001052-21016). We have also obtained ethical approvals from all the participating centres. The findings will be published in scientific and conference presentations. TRAIL REGISTRATION NUMBER: ChiCTR2100045668.


Assuntos
Reconciliação de Medicamentos , Farmacêuticos , Idoso , Hospitais de Condado , Humanos , Adesão à Medicação , Reconciliação de Medicamentos/métodos , Estudos Multicêntricos como Assunto , Estudos Prospectivos
10.
Basic Clin Pharmacol Toxicol ; 129(1): 15-25, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33915023

RESUMO

Polyphyllin I (PPI) and its analogues, including polyphyllin II (PPII), polyphyllin VI (PPVI) and polyphyllin VII (PPVII), are major bioactive compounds isolated from the Chinese herb Chonglou. However, the susceptibilities of PPI and its analogues towards the different cell lines are diversified and the mechanisms are not fully clarified. Thus, the present study aimed to investigate the cytotoxicity of PPI and its analogues on two different cell lines, as well as to explore the underlying mechanisms of these agents via inducing mitochondrial dysfunction. The results showed that PPI and its analogues were cytotoxic agents towards both A549 and HT-29 cells, with IC50 values ranged from 1.0 to 4.5 µmol/L. Further investigations demonstrated that they decreased the mitochondrial membrane potentials of both A549 and HT-29 cells in a dose-dependent manner. Among all tested compounds, PPVI and PPI induced the most obvious changes in Ca2+ haemostasis in these two cell lines. In addition, they could induce the accumulation of ROS in cells and down-regulated the Bcl-2 expression, up-regulated the Bax expression and induced the activity of cleaved caspase-3 in cells. Collectively, our findings clearly demonstrated the cytotoxic differences and mechanisms of PPI and its analogues induced cell apoptosis and could partially explain the anticancer effects of these natural constituents in Chonglou.


Assuntos
Diosgenina/análogos & derivados , Neoplasias Pulmonares/tratamento farmacológico , Células A549 , Apoptose/efeitos dos fármacos , Neoplasias do Colo , Diosgenina/farmacologia , Diosgenina/uso terapêutico , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Células HT29 , Humanos , Concentração Inibidora 50 , Neoplasias Pulmonares/patologia , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/patologia , Espécies Reativas de Oxigênio/metabolismo , Saponinas/farmacologia , Saponinas/uso terapêutico , Transdução de Sinais/efeitos dos fármacos , Esteroides/farmacologia , Esteroides/uso terapêutico
11.
J Hazard Mater ; 405: 124273, 2021 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-33131939

RESUMO

In the field of radioactive waste immobilization, the investigation of irradiation stability is of considerable importance. In this study, uranium-contaminated soil samples were irradiated by 1.5 MeV Xe20+ ions with fluences ranging from 1 × 1012 to 1 × 1015 ions/cm2. Xe20+ heavy-ion radiation was used to simulate the self-irradiation of actinide nuclides. The uranium-contaminated soil samples were sintered via microwaves. Grazing incidence X-ray diffraction results showed that irradiation can cause crystallization of the sample. After irradiation, the Vickers hardness of the samples decreased slightly. Comparative analysis showed that the sample had good radiation resistance, and the leaching rate (28 d) of the sample increased slightly after irradiation, but the overall performance was stable. Our investigation reveals the corresponding mechanism of uranium-contaminated soil irradiation of 1.5 MeV Xe20+ ions.

12.
J Hazard Mater ; 403: 123588, 2021 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-32777747

RESUMO

To better deal with the radioactive iodine generated during the development of nuclear energy, B2O3, Bi2O3, ZnO, and SiO2 were used to sinter borosilicate glass for the immobilization of iodine. The effect of B2O3 on glass formation was discussed by changing the molar ratio of B2O3 in the matrix. When B2O3 content is 50 mol% and sintering temperature is 600 ℃, the amorphous degree of quaternary glass is the highest. The sintered body with the highest degree of amorphous was selected to study radioactive iodine. Then, the effects of different iodine loading concentrations for sintering borosilicate glass in terms of microstructure and phase change were discussed. With the increase in iodine content on silica-gel, the degree of amorphous of the specimens presented a decreasing trend, and there are obvious SiO2 peaks. When the content was 20 wt.%-30 wt.%, a large number of new phases were generated. When the iodine content is 20 wt.%, in addition to the enrichment of Si and O elements, the elemental distribution for B, Bi, Zn, I, and Ag was even. TEM results also showed that there was a crystalline phase in the sinter.

13.
Se Pu ; 20(2): 108-14, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12541963

RESUMO

Three kinds of affinity membranes utilized for endotoxin removal, namely, chitosan affinity membrane (KFCC517), hydrophobic and cationic charged membrane (KFCG316) and metal chelate affinity membrane (KFCM402) were prepared by using cellulose membrane as support. The adsorbability and applications of the membranes in endotoxin removal were investigated. The results showed that all of these affinity membranes could be utilized for endotoxin removal in several kinds of solutions. The factors affecting endotoxin removal such as ionic strength, pH value and flow rate were investigated, and the results were discussed. Three cartridges of membranes KFCC517, KFCG316 and KFCM402 were utilized for endotoxin removal in human serum albumin solution. The cartridge of membrane KFCC517 also was utilized in medicine injections, such as hydrocortisone, puerarin, tetracaine hydrochloride and dextran 40 glucose. Under the optimal conditions, the removal efficiencies of endotoxin were over 80% and the recoveries of desirable substances were over 95%.


Assuntos
Cromatografia de Afinidade/métodos , Endotoxinas/isolamento & purificação , Hidrocortisona/isolamento & purificação , Albumina Sérica/isolamento & purificação , Adsorção , Cromatografia de Afinidade/instrumentação , Contaminação de Medicamentos , Isoflavonas/isolamento & purificação , Membranas Artificiais
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