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1.
Methods ; 220: 106-114, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37972913

RESUMO

Discovering new indications for existing drugs is a promising development strategy at various stages of drug research and development. However, most of them complete their tasks by constructing a variety of heterogeneous networks without considering available higher-order connectivity patterns in heterogeneous biological information networks, which are believed to be useful for improving the accuracy of new drug discovering. To this end, we propose a computational-based model, called SFRLDDA, for drug-disease association prediction by using semantic graph and function similarity representation learning. Specifically, SFRLDDA first integrates a heterogeneous information network (HIN) by drug-disease, drug-protein, protein-disease associations, and their biological knowledge. Second, different representation learning strategies are applied to obtain the feature representations of drugs and diseases from different perspectives over semantic graph and function similarity graphs constructed, respectively. At last, a Random Forest classifier is incorporated by SFRLDDA to discover potential drug-disease associations (DDAs). Experimental results demonstrate that SFRLDDA yields a best performance when compared with other state-of-the-art models on three benchmark datasets. Moreover, case studies also indicate that the simultaneous consideration of semantic graph and function similarity of drugs and diseases in the HIN allows SFRLDDA to precisely predict DDAs in a more comprehensive manner.


Assuntos
Algoritmos , Semântica , Serviços de Informação
2.
Molecules ; 29(5)2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38474519

RESUMO

A series of NH2-functionalized nano-sized magnetic metal-organic frameworks (MOFs) were prepared in this study for Cr(VI) removal from wastewater. It was observed that not only the morphological, i.e., orientation growth of N-doped and iron-based metal-organic frameworks, but also the adsorption of magnetic MOFs is largely related to the used amount of ammonium hydroxide in preparation. For example, with increasing amounts of ammonium hydroxide used in preparation, the morphology of magnetic MOFs changed from spherical to cube and triangular cone. Moreover, the maximum adsorption capacity of spherical-magnetic MOFs, cubic-magnetic MOFs and triangular cone-magnetic MOFs could be up to 204.08 mg/g, 232.56 mg/g and 270.27 mg/g, respectively. Under optimal conditions, the adsorption process of magnetic MOFs for Cr(VI) was consistent with the pseudo-second-order rate equation (R2 = 1) and Langmuir isotherm model (R2 > 0.99). Therefore, magnetic MOFs developed in this work offered a viable option for the removal of Cr(VI) from wastewater.

3.
J Neuroradiol ; 50(4): 415-423, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36462648

RESUMO

BACKGROUND AND PURPOSE: Endovascular treatment (EVT) is the best treatment for acute ischemic stroke with large vessel occlusion (LVO) and makes it possible to analyze the blood contents from the occluded vascular compartments. In this study, we attempted to evaluate regional changes in blood gas values and electrolytes in the occluded vessels, aiming to determine whether these changes can predict outcomes in LVO patients receiving EVT. MATERIALS AND METHODS: We prospectively observed 45 consecutive ischemic stroke patients with LVO of the anterior circulation who underwent EVT. We collected the arterial blood proximal to the occlusion site before and after EVT, and the blood within the core of the occluded vascular compartment (distal to the thrombus) and evaluated the labs for blood gas values and electrolytes. Femoral samples were obtained under physiological flow conditions to represent systemic arterial blood. RESULTS: Compared with the femoral arterial blood samples, significant decreases in K+, Ca2+, HCO3-, BE, HCT, tHbc, and TCO2 levels were observed in the proximal luminal blood before EVT. Decreases in K+ and Ca2+ levels were also observed in the proximal luminal blood after EVT. Proximal/femoral ratio of pH and Na+ was associated with short-term clinical outcomes at 72 hours after EVT. A higher proximal/femoral Na+ ratio was associated with successful recanalization. Further analysis after propensity score matching showed significant changes in blood gas and electrolyte among different arterial locations in ICA and MCA LVO participants. Linear regression analyses indicated that the proximal/femoral ratio of pH, Na+, pCO2, HCO3, and TCO2 before EVT were associated with decrease in NIHSS score at 72 hours in ICA-LVO group. CONCLUSIONS: Obvious changes in several parameters of arterial blood gas and electrolyte from the ischemic vasculature occur during hyperacute stroke. Proximal/femoral pH and Na+ ratio before EVT may be associated with short-term clinical outcome, which deserve to be further investigated.


Assuntos
Isquemia Encefálica , Procedimentos Endovasculares , AVC Isquêmico , Acidente Vascular Cerebral , Humanos , Cálcio , Trombectomia , Resultado do Tratamento , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/terapia , Acidente Vascular Cerebral/etiologia , Eletrólitos , Procedimentos Endovasculares/efeitos adversos , Artérias , Isquemia Encefálica/diagnóstico por imagem , Isquemia Encefálica/cirurgia
4.
Molecules ; 27(17)2022 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-36080279

RESUMO

In this work, magnetic tetraethylenepentamine (TEPA)-modified carboxyl-carbon nanotubes were synthesized, characterized, and used as adsorbents to conduct magnetic solid-phase extraction (MSPE) for the preconcentration of seven local anesthetic drugs (procaine, lidocaine, mepivacaine, oxybuprocaine, bupivacaine, tetracaine, and cinchocaine) from human plasma. The separation and determination of analytes were performed on high-performance liquid chromatography with UV detection. Several factors affected the extraction efficiency, such as the amount of adsorbents used, extraction time, sample pH, and optimization of elution conditions. Under optimal conditions, satisfactory linear relationships were obtained in the range of 0.02-5.00 mg/L, with the limits of detection (LOD) ranging from 0.003 mg/L to 0.008 mg/L. The recoveries of analytes for spiked human plasma were in the range of 82.0-108%. Moreover, the precision with intra-day and inter-day RSD values were obtained in the range of 1.5-7.7% and 1.5-8.3%. The results indicated that this method could determine the concentration of seven local anesthetic drugs in human plasma with high precision and repeatability and provide support for the clinical monitoring of the concentration of local anesthetic drugs in human plasma.


Assuntos
Anestésicos Locais , Nanotubos de Carbono , Cromatografia Líquida de Alta Pressão/métodos , Humanos , Fenômenos Magnéticos , Extração em Fase Sólida/métodos
5.
Am J Ther ; 25(3): e291-e298, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-26910056

RESUMO

To determine the effects of 80-mg atorvastatin administration for the first time in patients with acute ST segment elevation myocardial infarction (STEMI) before emergency percutaneous coronary intervention (PCI). A total of 118 patients with STEMI who underwent emergency PCI were enrolled in this study. The patients were divided into 80-mg group (n = 59) and 40-mg group (n = 59), according to the loading dose of atorvastatin firstly before operation. The occurrence of no-reflows and changes of HbA1c were observed preoperatively and postoperatively on second and fifth days. All patients were followed up for 1 year with major adverse cardiac events (MACE) recorded. The incidence of no-reflow in 80-mg group was obviously lower than in 40-mg group (13.56% vs. 25.42%) (χ = 4.374, P = 4.374). The preoperative HbA1c levels exhibited no significant difference between 80-mg group and 40-mg group (P > 0.05). The postoperative HbA1c levels in 2 groups showed a trend of gradual decline, which were lower in 80-mg group than in 40-mg group for second day, fifth day, first month, sixth month, and 12th month (all P < 0.05). The postoperative incidence of MACE in 80-mg group was significantly lower than in 40-mg group for sixth and 12th months (both P < 0.05). The incidence of MACE in patients with reflow in 80-mg and 40-mg groups was significantly higher than in patients with no-reflow who were in 80-mg and 40-mg groups for postoperative 12th month (both P < 0.05). The first loading high dose of atorvastatin can significantly prevent occurrence of postoperative no-reflow in patients with STEMI after PCI, reduce HbA1c levels and the incidence of MACE. Clinical randomized controlled trial with larger sample size is required to confirm this finding.


Assuntos
Atorvastatina/uso terapêutico , Tratamento de Emergência/métodos , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Intervenção Coronária Percutânea/métodos , Infarto do Miocárdio com Supradesnível do Segmento ST/terapia , Idoso , Angiografia Coronária , Relação Dose-Resposta a Droga , Feminino , Hemoglobinas Glicadas/análise , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Fenômeno de não Refluxo/diagnóstico por imagem , Fenômeno de não Refluxo/epidemiologia , Período Perioperatório , Cuidados Pré-Operatórios/métodos , Infarto do Miocárdio com Supradesnível do Segmento ST/sangue , Infarto do Miocárdio com Supradesnível do Segmento ST/diagnóstico por imagem , Resultado do Tratamento
6.
J Sep Sci ; 41(22): 4096-4104, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30230241

RESUMO

A simple, cost-effective, sensitive, and quick method for the determination of nitenpyram and its metabolite 6-chloronicotinic acid in environmental samples was developed by coupling an ion chromatograph with a fluorescence detector and a post-column photochemical reactor. This developed analytical method involved a rapid sample extraction by modified and miniaturized quick, easy, cheap, effective, rugged, and safe method followed by isocratic ion chromatographic separation of nitenpyram and 6-chloronicotinic acid into an IonPac™ AS11-HC column protected by IonPac™ AG11A guard column by running 30 mM NaOH + 10% acetonitrile mobile phase. A homemade post-column photochemical reactor was also integrated with the ion chromatographic system for online transformation of both analytes into their respective highly fluorescent photoproduct in basic media without using an extra pump. The developed method was validated by following SANTE/11945/2015 guidelines on analytical quality control and validation procedures. The method showed a good linear response (r > 0.999), improved limit of detection (0.101-0.132 µg/L), minimum or no matrix effect, excellent recoveries (90.2-100.10%) and relative standard deviations were found to be ≤6.50%.


Assuntos
Poluentes Ambientais/química , Neonicotinoides/análise , Ácidos Nicotínicos/análise , Cromatografia por Troca Iônica , Monitoramento Ambiental , Estrutura Molecular , Processos Fotoquímicos , Espectrometria de Fluorescência
7.
J Sep Sci ; 40(22): 4294-4302, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28960918

RESUMO

A directly-coupled-column ultra-fast liquid chromatography coupled with diode array detection method for the determination of 12 allergenic disperse dyes in river water at sub-ppb levels has been developed and successfully validated. The analytical method is based on the use of two different reversed-phased columns connected through a two-position switching valve. A baseline separation was achieved by proper selection of stationary phases, mobile phases, and the use of a gradient elution in both dimensions. Furthermore, an easy-to-handle magnetic solid-phase extraction procedure was developed for the preconcentration of 12 allergenic disperse dyes from river water. An enrichment factor of 100 times was obtained. The results showed excellent performance in terms of trueness (76.8-99.0%), precision (intraday: 2.2-8.0%, interday: 3.3-8.2%), and sensitivity (limits of determination, 0.027-1.46 µg/L). Twenty real samples collected from the outfalls in the Yaojiang, Yongjiang and Fenghuajiang estuary were analyzed, and three of the studied compounds were found in one collected sample (12.6 µg/L for disperse blue 7, 11.6 µg/L for disperse blue 106, and 0.22 µg/L for disperse blue 3).

8.
Biochem Biophys Res Commun ; 470(2): 287-293, 2016 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-26797522

RESUMO

Matrix metalloproteinase-2 (MMP-2), also known as gelatinase A, is involved in vascular calcification. Another member of gelatinases is MMP-9 (gelatinase B). However, the role of gelatinases in the pathogenesis of vascular calcification is not well understood. The current study aims to clarify the relationship between gelatinases and vascular calcification and to elucidate the underlying mechanism. Beta-glycerophosphate (ß-GP) was used to induce calcification of vascular smooth muscle cells (VSMCs) with or without 2-[[(4-Phenoxyphenyl)sulfonyl]methyl]-thiirane (SB-3CT), a specific gelatinases inhibitor. Levels of calcification were determined by assessing calcium content and calcification area of VSMCs. Phenotype transition of VSMCs was observed by assessing expressions of alkaline phosphatase (ALP), smooth muscle α-actin (SM-α-actin) and desmin. Gelatin zymography was applied to determine the activities of gelatinases, and western blot was applied to determine expressions of gelatinases, bone morphogenetic protein-2 (BMP-2), Runt-related transcription factor 2 (RUNX2) and msh homeobox homolog 2 (Msx-2). Gelatinases inhibition by SB-3CT alleviated calcification and phenotype transition of VSMCs induced by ß-GP. Increased gelatinases expression and active MMP-2 were observed in calcifying VSMCs. Gelatinases inhibition reduced expression of RUNX2, Msx-2 and BMP-2. BMP-2 treatment increased expressions of RUNX2 and Msx-2, while noggin, an antagonist of BMP-2, decreased expressions of RUNX2 and Msx-2. Gelatinases promote vascular calcification by upregulating BMP-2 which induces expression of RUNX2 and Msx-2, two proteins associated with phenotype transition of VSMCs in vascular calcification. Interventions targeting gelatinases inhibition might be a proper candidate for ameliorating vascular calcification.


Assuntos
Proteína Morfogenética Óssea 2/metabolismo , Gelatinases/metabolismo , Músculo Liso Vascular/metabolismo , Miócitos de Músculo Liso/metabolismo , Calcificação Vascular/metabolismo , Calcificação Vascular/patologia , Animais , Células Cultivadas , Masculino , Músculo Liso Vascular/patologia , Ratos , Ratos Wistar , Regulação para Cima
9.
J Sep Sci ; 39(4): 762-8, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26632107

RESUMO

A novel triethylenetetramine-functionalized magnetic graphene oxide composite was prepared and used as a magnetic solid-phase extraction adsorbent for the fast detection of ten trace-level phenolic environmental estrogens in environmental water. The synthesized material was carefully characterized by scanning electron microscopy, transmission electron microscopy, vibrating sample magnetometry, and X-ray photoelectron spectroscopy to confirm the structure and components. The adsorption and desorption conditions of the adsorbent toward phenolic environmental estrogens were optimized in detailed to obtain the best extraction recovery and elution efficiency. Under the optimum conditions, the limits of detection of the method for ten phenolic environmental estrogens were in range of 0.15-1.5 ng/L, which was lower than the reported methods for phenolic environmental estrogens detection in literatures. This could be contributed to the unique structure and property of the as-prepared material. The developed method was successfully applied for the determination of environmental water samples with recoveries ranging from 88.5 to 105.6%.


Assuntos
Estrogênios/química , Grafite/química , Magnetismo , Óxidos/química , Fenol/química , Trientina/química , Água/química , Adsorção , Cromatografia Líquida de Alta Pressão , Monitoramento Ambiental/métodos , Poluentes Ambientais , Limite de Detecção , Impressão Molecular , Polímeros/química , Reprodutibilidade dos Testes , Solventes/química , Poluentes Químicos da Água/química
10.
Bioorg Med Chem ; 22(2): 692-702, 2014 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-24388993

RESUMO

Novel series of N-(5-(arylcarbonyl)thiazol-2-yl)amides and N-(5-(arylcarbonyl)thiophen-2-yl)amides were discovered as potent retinoic acid receptor-related orphan receptor-gamma-t (RORγt) inhibitors. SAR studies of the RORγt HTS hit 6a led to identification of thiazole ketone amide 8h and thiophene ketone amide 9g with high binding affinity and inhibitory activity of Th17 cell differentiation. Compound 8h showed in vivo efficacy in both mouse experimental autoimmune encephalomyelitis (EAE) and collagen induced arthritis (CIA) models via oral administration.


Assuntos
Amidas/farmacologia , Artrite/tratamento farmacológico , Descoberta de Drogas , Encefalomielite Autoimune Experimental/tratamento farmacológico , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/antagonistas & inibidores , Administração Oral , Amidas/administração & dosagem , Amidas/química , Animais , Artrite/induzido quimicamente , Diferenciação Celular/efeitos dos fármacos , Colágeno , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Humanos , Camundongos , Estrutura Molecular , Relação Estrutura-Atividade , Células Th17
11.
Pharmaceutics ; 16(1)2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-38276519

RESUMO

The unique properties of ionic liquids (ILs), such as structural tunability, good solubility, chemical/thermal stability, favorable biocompatibility, and simplicity of preparation, have led to a wide range of applications in the pharmaceutical and biomedical fields. ILs can not only speed up the chemical reaction process, improve the yield, and reduce environmental pollution but also improve many problems in the field of medicine, such as the poor drug solubility, product crystal instability, poor biological activity, and low drug delivery efficiency. This paper presents a systematic and concise analysis of the recent advancements and further applications of ILs in the pharmaceutical field from the aspects of drug synthesis, drug analysis, drug solubilization, and drug crystal engineering. Additionally, it explores the biomedical field, covering aspects such as drug carriers, stabilization of proteins, antimicrobials, and bioactive ionic liquids.

12.
J Chromatogr A ; 1725: 464962, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38704923

RESUMO

Because of the "enterohepatic circulation" of bile acid, liver damage can be reflected by monitoring the content of bile acid in the serum of the organism. To monitor the concentration of 15 bile acids in plasma samples, a new technique of PRiME (process, ruggedness, improvement, matrix effect, ease of use) pass-through cleanup procedure combined with high performance liquid chromatography-tandem quadrupole mass spectrometry (HPLC-MS/MS) was developed. The sorbent used in the PRiME pass-through cleanup procedure is a new type of magnetic organic resin composite nano-material modified by C18 (C18-PS-DVB-GMA-Fe3O4), which has high cleanup efficiency of plasma samples. It also shows good performance in the separation and analysis of 15 kinds of bile acids. Under the optimal conditions, the results show higher cleanup efficiency of C18-PS-DVB-GMA-Fe3O4 with recoveries in the range of 82.1-115 %. The limit of quantitative (LOQs) of 15 bile acids were in the range of 0.033 µg/L-0.19 µg/L, and the RSD values of 15 bile acids were in the range of 3.00-11.9 %. Validation results on linearity, specificity, accuracy and precision, as well as on the application to analysis of 15 bile acids in 100 human plasma samples demonstrate the applicability to clinical studies.


Assuntos
Ácidos e Sais Biliares , Limite de Detecção , Nanocompostos , Espectrometria de Massas em Tandem , Humanos , Ácidos e Sais Biliares/sangue , Ácidos e Sais Biliares/química , Espectrometria de Massas em Tandem/métodos , Nanocompostos/química , Cromatografia Líquida de Alta Pressão/métodos , Reprodutibilidade dos Testes , Polímeros/química , Nanopartículas de Magnetita/química
13.
CNS Neurosci Ther ; 30(3): e14687, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38497517

RESUMO

AIMS: This study aimed to compare the clinical outcomes and safety of endovascular treatment (EVT) in patients with primary versus secondary medium vessel occlusion (MeVO). METHODS: From the endovascular treatment for acute ischemic stroke in the China registry, we collected consecutive patients with MeVO who received EVT. The primary endpoint was a good outcome, defined as a modified Rankin Scale (mRS) 0 to 2 at 90 days. RESULTS: 154 patients were enrolled in the final analysis, including 74 primary MeVO and 80 secondary MeVO. A good outcome at 90 days was achieved in 42 (56.8%) patients with primary MeVO and 33 (41.3%) patients with secondary MeVO. There was a higher probability of good outcomes in patients with the primary vs secondary MeVO (adjusted odds ratio, 2.16; 95% confidence interval, 1.04 to 4.46; p = 0.04). There were no significant differences in secondary and safety outcomes between MeVO groups. In the multivariable analysis, baseline ASPECTS (p = 0.001), final modified thrombolysis in cerebral infarction score (p = 0.01), and any ICH (p = 0.03) were significantly associated with good outcomes in primary MeVO patients, while baseline National Institutes of Health Stroke Scale (p = 0.002), groin puncture to recanalization time (p = 0.02), and early neurological improvement (p < 0.001) were factors associated with good outcome in secondary MeVO patients. CONCLUSION: In MeVO patients who received EVT, there was a higher likelihood of poor outcomes in patients with secondary versus primary MeVO.


Assuntos
Isquemia Encefálica , Procedimentos Endovasculares , AVC Isquêmico , Acidente Vascular Cerebral , Estados Unidos , Humanos , Acidente Vascular Cerebral/cirurgia , Acidente Vascular Cerebral/etiologia , Isquemia Encefálica/cirurgia , Isquemia Encefálica/etiologia , Resultado do Tratamento
14.
Natl Sci Rev ; 11(4): nwae063, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38623453

RESUMO

The Chinese Bayan Obo deposit is a world-class rare earth element (REE) deposit with considerable niobium (Nb) and iron (Fe) resources. A complete genetic understanding on all metals is fundamental for establishing genetic models at Bayan Obo. With extensive research being focused on REE enrichment, the timing and controls of Nb enrichment remain unresolved at Bayan Obo, which is mainly due to the challenges in dating, i.e. multistage thermal events, fine-grained minerals with complex textures and the rare occurrence of uranium-enriched minerals with mature dating methods. Based on robust geological and petrographic frameworks, here we conducted ion probe uranium-lead (U-Pb) dating of ferrocolumbite to unravel the timing, hence the genesis of Nb mineralization. Three types of hydrothermal ferrocolumbites-key Nb-bearing minerals-are identified based on their textures and mineral assemblages. They yield U-Pb ages of 1312 ± 47 Ma (n = 99), 438 ± 7 Ma (n = 93), and 268 ± 5 Ma (n = 19), respectively. In line with deposit geology, we tentatively link the first, second and third stage Nb mineralization to Mesoproterozoic carbonatite magmatism, ubiquitous early Paleozoic hydrothermal activity, and Permian granitic magmatism, respectively. While quantifying the contribution of metal endowment from each stage requires further investigation, our new dates highlight that multi-stage mineralization is critical for Nb enrichment at Bayan Obo, which may also have implications for the enrichment mechanism of Nb in REE deposits in general.

15.
Contemp Oncol (Pozn) ; 17(6): 525-9, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24592141

RESUMO

AIM OF THE STUDY: The present study aims to discuss the value and the effect of resection of suprasellar meningioma through the interhemispheric approach. MATERIAL AND METHODS: Twenty-nine cases of patients with suprasellar meningioma diagnosed through enhanced magnetic resonance imaging (MRI) scans and postoperative histopathological examination underwent resection of tumours (the largest diameter ranged from 3 cm to 6 cm) by the microsurgical technique of a small bone window (about 4 cm × 5 cm) through the interhemispheric approach. RESULTS: Among all cases, 25 (86%) (Simpson I, II) were of total resection of tumours and 4 were of subtotal resection of tumours. 19 (65%) were of improvement of vision and visual field, 2 (7%) were of postoperative diabetes insipidus, and 1 (3%) was of electrolyte imbalance. No operative death occurred. CONCLUSIONS: The small bone window interhemispheric approach can be used to expose tumours, lightly stretch brain tissues, reduce the incidence of complications, and improve the total resection rate of tumours of patients with sellae meningiomas growing forward, upward, and into the sella.

16.
J Mass Spectrom ; 58(2): e4905, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36775912

RESUMO

The determination of isotope ratios in individual uranium particles is very important for nuclear safeguards. In this work, accelerator mass spectrometry (AMS), thermal ionization mass spectrometry (TIMS), and secondary ion mass spectrometry (SIMS) were applied to isotope ratio analysis of individual uranium particles and compared in terms of background, measurement accuracy, and efficiency. Several individual uranium particles (1-7 µm) from certified reference materials were used as samples. The results show that the average values of blank counting rate of 235 U for AMS, FT-TIMS (FT: fission track), SEM-TIMS (SEM: scanning electron microscope), and SIMS were 7.3, 7.8, 2.7 and 2.2 cps, respectively. The relative error of 234 U/235 U and 234 U/236 U isotope ratios of the particles from U200 for AMS were within 10% and 20%, whereas the results of FT-TIMS and SIMS were within 5% and 10%, respectively. The relative error and external precision of 234 U/238 U and 235 U/238 U of the particles from U850 for the method of AMS, SEM-TIMS, and SIMS were within 10% and 5%, respectively. For 236 U/238 U, the average values of the relative error and external precision measured by AMS were within 5%, which measured by SEM-TIMS and SIMS were all within 10%. AMS has advantages in measuring 236 U/238 U. The measurement time of AMS and SEM-TIMS was shorter than that of FT-TIMS and longer than that of SIMS. It is considered that AMS and SEM-TIMS have a certain development prospect, and it is necessary to research deeply.

17.
Nanomaterials (Basel) ; 13(6)2023 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-36986005

RESUMO

A new type of magnetic nanomaterial with Fe3O4 as the core and organic polymer as the shell was synthesized by seed emulsion polymerization. This material not only overcomes the problem of insufficient mechanical strength of the organic polymer, it also solves the problem that Fe3O4 is prone to oxidation and agglomeration. In order to make the particle size of Fe3O4 meet the requirement of the seed, the solvothermal method was used to prepare Fe3O4. The effects of the reaction time, amount of solvent, pH value, and polyethylene glycol (PEG) on the particle size of Fe3O4 were investigated. In addition, in order to accelerate the reaction rate, the feasibility of preparing Fe3O4 by microwave was studied. The results showed that under the optimum conditions, the particle size of Fe3O4 could reach 400 nm and had good magnetic properties. After three stages of oleic acid coating, seed emulsion polymerization, and C18 modification, the obtained C18-functionalized magnetic nanomaterials were used for the preparation of the chromatographic column. Under optimal conditions, stepwise elution significantly shortened the elution time of sulfamethyldiazine, sulfamethazine, sulfamethoxypyridazine, and sulfamethoxazole while still achieving a baseline separation.

18.
Int J Biol Macromol ; 242(Pt 3): 125043, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37224909

RESUMO

The investigation of interaction mechanism of U(VI) selective removal on amidoxime-functionalized metal organic framework (i.e., UiO-66(Zr)-AO) derived from macromolecular carbohydrate is conducive to apply metal organic frameworks in actual environmental remediation. The batch experiments showed that UiO-66(Zr)-AO displayed the fast removal rate (equilibrium time of 0.5 h), high adsorption capacity (384.6 mg/g), excellent regeneration performance (<10 % decrease after three cycles) towards U(VI) removal due to the unprecedented chemical stability, large surface area and simple fabrication. U(VI) removal at different pH can be satisfactorily fitted by diffuse layer modeling with cation exchange at low pH and an inner-sphere surface complexation at high pH. The inner-sphere surface complexation was further demonstrated by X-ray absorption near edge structure (XANES) and extended X-ray absorption fine structure (EXAFS) analysis. These findings revealed that UiO-66(Zr)-AO can be an effective adsorbent to remove the radionuclides from aqueous solution, which is crucial for recycling of uranium resource and decreasing the uranium harm to the environment.


Assuntos
Estruturas Metalorgânicas , Urânio , Urânio/química , Porosidade , Adsorção
19.
J Mass Spectrom ; 58(11): e4979, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37903512

RESUMO

Electrospray Ionization Mass Spectrometry (ESI-MS) technique and density functional theory (DFT) calculations were combined to study the formation of the complexes of lanthanides (Ln = La, Ce, Nd, Sm, Eu, Yb) and actinides (UO2 2+ , Th4+ ) with CyMe4 -BTBP (6,6'-bis(5,5,8,8-tetramethyl-5,6,7,8-tetrahydro-benzo-[1,2,4-]triazin-3-yl)-[2,2']bipyridine) to understand the mechanisms during the extraction process. Mass spectrometry titrations showed the formation of the complexation in acetonitrile. For lanthanides, only 1:2 complexes ([Ln(L)2 ]3+ , [Ln(L)2 (CH3 CN)]3+ ), [Ln(L)2 (NO3 )]2+ ) were found at low [Ln]/[L] concentration ratios, whereas the 1:1 complexes ([Ln(L)(NO3 )2 ]+ ) were observed when the [Ln]/[L] concentration ratio reached 1.0. For uranyl complexes, 1:1 complex ([UO2 L(NO3 )]+ ) was the only species within the measuring range. Th4+ complexes had two compositions: 1:1 and 1:2, in which 1:2 species was the dominant complex. Collision-induced dissociation (CID) was employed to characterize the fragmentation process. The fragmentation process was unfolded sequentially on both sides of CyMe4 -BTBP ligand with the loss of alkyl groups and cleavage of triazinyl rings. The CID results of CyMe4 -BTBP complexes revealed a slight difference depending on the metal center. The DFT calculations showed that the stable complexes formed in acetonitrile solution were consistent with the ESI-MS results.

20.
J Neurointerv Surg ; 15(e3): e356-e362, 2023 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-36627195

RESUMO

BACKGROUND: The aim of the study was to establish a reliable scoring tool to identify the probability of symptomatic intracranial hemorrhage (sICH) in anterior circulation stroke patients with contrast enhancement (CE) on brain non-contrast CT (NCCT) after endovascular thrombectomy (EVT). METHODS: We retrospectively reviewed consecutive patients with acute ischemic stroke (AIS) who had CE on NCCT immediately after EVT for anterior circulation large vessel occlusion (LVO). We used the Alberta stroke program early CT score (ASPECTS) scoring system to estimate the extent and location of CE. Multivariable logistic regression was performed to derive an sICH predictive score. The discrimination and calibration of this score were assessed using the area under the receiver operator characteristic curve, calibration curve, and decision curve analysis. RESULTS: In this study, 194 of 322 (60.25%) anterior circulation AIS-LVO patients had CE on NCCT. After excluding 85 patients, 109 patients were enrolled in the final analysis. In multivariate regression analysis, age ≥70 years (adjusted OR (aOR) 9.23, 95% CI 2.43 to 34.97, P<0.05), atrial fibrillation (AF) (aOR 4.17, 95% CI 1.33 to 13.12, P<0.05), serum glucose ≥11.1 mmol/L (aOR 9.39, 95% CI 2.74 to 32.14, P<0.05), CE-ASPECTS <5 (aOR 3.95, 95% CI 1.30 to 12.04 P<0.05), and CE at the internal capsule (aOR 3.45, 95% CI 1.03 to 11.59, P<0.05) and M1 region (aOR 3.65, 95% CI 1.13 to 11.80, P<0.05) were associated with sICH. These variables were incorporated as the CE-age-glucose-AF (CAGA) score. The CAGA score demonstrated good discrimination and calibration in this cohort, as well as the fivefold cross validation. CONCLUSION: The CAGA score reliably predicted sICH in patients with CE on NCCT after EVT treatment.


Assuntos
Isquemia Encefálica , Procedimentos Endovasculares , AVC Isquêmico , Acidente Vascular Cerebral , Humanos , Idoso , Estudos Retrospectivos , AVC Isquêmico/etiologia , Isquemia Encefálica/diagnóstico por imagem , Isquemia Encefálica/cirurgia , Isquemia Encefálica/complicações , Resultado do Tratamento , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/cirurgia , Acidente Vascular Cerebral/complicações , Hemorragias Intracranianas/etiologia , Hemorragias Intracranianas/complicações , Trombectomia/efeitos adversos , Glucose , Procedimentos Endovasculares/efeitos adversos
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