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1.
Int J Biol Macromol ; 254(Pt 3): 128008, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37951068

RESUMO

In order to improve the removal rate of uranium and reduce the harm of radioactive pollution, a physically crosslinked polyvinyl alcohol/phosphorylated chitosan (PPP) hydrogel electrode was designed by freezing thawing method. The results show that PPP hydrogel has a good adsorption effect on uranium, and 200 mL of uranium tailings leachate is absorbed, and the treatment efficiency reaches 100 % within 15 min. PPP hydrogel can adapt to a wide range of pH conditions and exhibit excellent adsorption efficiency in the range of 3-9. At the same time, PPP hydrogel maintains an adsorption efficiency of over 85 % for 950 mg/L uranium solution. This lays the foundation for the practical application of PPP hydrogel. In addition, PPP hydrogel also exhibits good repeatability, after 7 cycles, the material still retains 95 % of its initial performance. The synergistic effect of various functional groups such as phosphate, hydroxyl, and ammonium in the material is the main mechanism of PPP's adsorption capacity for uranium. Furthermore, electrochemical adsorption method significantly enhances the adsorption performance of PPP hydrogel.


Assuntos
Quitosana , Urânio , Ácido Fítico , Álcool de Polivinil , Concentração de Íons de Hidrogênio , Hidrogéis , Adsorção
2.
Int J Biol Macromol ; 238: 124074, 2023 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-36934816

RESUMO

A novel chitosan-based porous composite adsorbent with multifunctional groups, such as phosphoric acid, amidoxime, and quaternary ammonium groups, was prepared to improve the adsorption rate and competitive uranium­vanadium adsorption of amidoxime group adsorbents. The maximum uranium adsorption capacity of PACNC was 962.226 mg g-1 at 308 K and pH = 7. The maximum adsorption rate constant of PACNC for uranium was 2.83E-2 g mg-1 min-1, which is 2.38 times that of ACNC (1.19E-2 g mg-1 min-1). Moreover, the adsorption equilibrium time was shortened from 300 (ACNC) to 50 (PACNC) min. In simulated and real seawater, the Kd and adsorption capacity of PACNC for uranium were approximately 8 and 6.62 times those for vanadium, respectively. These results suggest that phosphorylation significantly improved the competitive adsorption of uranium­vanadium and uranium adsorption rate. PACNC also exhibited good recycling performance and maintained stable adsorption capacity after five cycles. DFT calculations were used to analyze and calculate the possible co-complex structure of PACNC and uranium. The binding structure of phosphate and amidoxime is the most stable, and its synergistic effect effectively improves the competitive adsorption of uranium-vanadium of amidoxime. All the results demonstrated that PACNC has substantial application potential for uranium extraction from seawater.


Assuntos
Quitosana , Urânio , Urânio/química , Quitosana/química , Adsorção , Fosforilação , Vanádio , Água do Mar/química
3.
Carbohydr Polym ; 300: 120270, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36372493

RESUMO

In this study, a novel sponge phosphoric acid functionalized porous composite adsorbent (named SPCCHC) was prepared from chitosan and chlorella hydrothermal charcoal. Kinetics and thermodynamics experiments showed that the theoretical maximum adsorption capacity of SPCCHC to U(VI) is 579.27 mg/g (288 K, pH = 6.5), indicating a spontaneous exothermic reaction. SPCCHC showed good adsorption selectivity for uranium in the adsorption studies of simulated seawater and a mixed solution of uranium-vanadium. The characterization of SPCCHC before and after U(VI) adsorption proves that the introduction of the phosphate group can greatly improve the adsorption effect of the adsorbent on uranium, particularly the distribution coefficients of uranium and vanadium differ by up to 89.5 times. At the same time, SPCCHC has good recycling performance, which is expected to be used in natural seawater uranium extraction.


Assuntos
Quitosana , Chlorella , Urânio , Urânio/química , Quitosana/química , Vanádio , Adsorção , Cinética
4.
J Ethnopharmacol ; 289: 115028, 2022 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-35077825

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Yiqi Shengsui formula (YQSSF) is a commonly used formula to treat chemotherapy-induced myelosuppression, but little is known about its therapeutic mechanisms. AIM OF THIS STUDY: This study aims to examine the effect of YQSSF in treating myelosuppression and explore its mechanism. MATERIALS AND METHODS: A myelosuppression BALB/c mouse model was established by intraperitoneal (i.p.) injection of cyclophosphamide (CTX). The efficacy of YQSSF in alleviating chemotherapy-induced myelosuppression was evaluated by blood cell count, immune organ (thymus, spleen, liver) index, bone marrow nucleated cell (BMNC) count and histopathological analysis of bone marrow and spleen. Then, ultra-performance liquid chromatograph quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF/MS) was performed to analyze the ingredients of YQSSF extract. Key effects and potential mechanism of YQSSF extract in alleviating myelosuppression were predicted by network pharmacology method. Finally, cell cycle and TUNEL staining of bone marrow cells was detected to verify the key effects, and RT-qPCR or Western blotting were performed to measure the gene and protein expressions of the effect targets respectively to confirm the predicted mechanism of YQSSF for myelosuppression. RESULTS: YQSSF up-regulated the number of peripheral blood leukocytes and BMNC, reduced spleen index and liver index, improved the pathological morphology of bone marrow and spleen. A total of 40 ingredients were isolated from YQSSF extract using UPLC-Q/TOF-MS analysis. Network pharmacology revealed that YQSSF regulated both proliferation and apoptosis to alleviate myelosuppression. Finally, YQSSF decreased G0/G1 ratio, increased the proportion of bone marrow cells in S phase and proliferation index (PI), and reduced apoptotic cells in femur bone marrow. RT-qPCR and Western blotting showed that YQSSF up-regulated the expression levels of CDK4, CDK6, CyclinB1, c-Myc and Bcl-2, as well as down-regulated the expression levels of Cyt-c, Fas, Caspase-8/3 and p53. CONCLUSIONS: YQSSF promotes the proliferation and inhibits the apoptosis of bone marrow cells to relieve chemotherapy-induced myelosuppression.


Assuntos
Células da Medula Óssea/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Ciclofosfamida/toxicidade , Medicamentos de Ervas Chinesas/farmacologia , Animais , Antineoplásicos Alquilantes/toxicidade , Apoptose/efeitos dos fármacos , Células da Medula Óssea/citologia , Ciclo Celular/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos BALB C
5.
Prostaglandins Other Lipid Mediat ; 158: 106608, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34958945

RESUMO

The objective of this study was to investigate the protective effects of Shengmai Yin(SMY) on rats with chronic heart failure(CHF).Sprague-Dawley rats were used to establish a CHF animal model via ligation of the left anterior descending branch of the coronary artery and exhaustive swimming.Echocardiography, serum biochemical indicators and histopathology were used to evaluate the pharmacodynamics of SMY in CHF rats.UPLC-Q-TOF/MS analysis based on serum was performed to identify the potential metabolites in the pathological process of CHF. Metabolic pathway analysis was carried out to elucidate the metabolic network associated with SMY treatment of CHF.Moreover,quantitative real-time PCR (qRT-PCR), Western blotting (WB), and Enzyme-linked immunosorbent assay (ELISA) were used to measure the RNA and protein expression levels in related pathways. Results revealed that SMY significantly restored the cardiac function of CHF rats, reduced the serum biochemical indicators, and alleviated cardiac histological damage. Metabolomics analysis shows that the therapeutic effect of SMY for CHF involves 14 biomarkers and 8 metabolic pathways, especially linoleic acid pathway, to be influenced, which implied the potential mechanism of SMY in treating CHF. Two key indicators Lipoxygenase arachidonic acid 15 lipoxygenase (ALOX15) and Cytochrome P450 1A2(CYP1A2) of linoleic acid metabolism pathway were verified by RT-PCR, WB and ELISA. Verification result showed that compared with the model group, expression levels of ALOX15 and CYP1A2 in SMY group were lower. In conclusion, SMY has cardioprotective effect on chronic heart failure rats, and its mechanism may be related to linoleic acid metabolism pathway.


Assuntos
Medicamentos de Ervas Chinesas , Insuficiência Cardíaca , Animais , Combinação de Medicamentos , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/uso terapêutico , Insuficiência Cardíaca/tratamento farmacológico , Insuficiência Cardíaca/metabolismo , Ácido Linoleico/farmacologia , Metabolômica , Ratos , Ratos Sprague-Dawley
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