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The dimethyl maleate hydrogenation activity of Cu, ZnO-X and physically mixed Cu+ZnO-X samples was systematically investigated to probe the essential role of ZnO in ester hydrogenation processes. Cu samples exhibited high CîC bond hydrogenation ability with dimethyl succinate as the main product. Comparatively, ZnO was inactive in hydrogenation due to its weak ability to dissociate hydrogen while the CîO group could be activated and adsorbed on the ZnO surface. Interestingly, physical mixing with ZnO significantly improved the CîO hydrogenation activity of Cu samples. The H2-TPD results reveal the origin of "Cu-ZnO synergy": hydrogen atoms formed on the copper surface can spill over to the ZnO surface and react with the adsorbed CîO group.
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Anthropogenic emissions have resulted in increases in the atmospheric fluxes of both nutrient and toxic elements. However, the long-term geochemical impacts on lake sediments of deposition activities have not been clearly clarified. We selected two small enclosed lakes in northern China-Gonghai, strongly influenced by anthropogenic activities, and Yueliang lake, relatively weakly influenced by anthropogenic activities-to reconstruct historical trends of atmospheric deposition on the geochemistry of the recent sediments. The results showed an abrupt rise in the nutrient levels in Gonghai and the enrichment of toxic metal elements from 1950 (the Anthropocene) onwards. While, at Yueliang lake, the rise on TN was from 1990 onwards. These consequences are attributable to the aggravation of anthropogenic atmospheric deposition in N, P and toxic metals, from fertilizer consumption, mining and coal combustion. The intensity of anthropogenic deposition is considerable, which leave a significant stratigraphic signal of the Anthropocene in lake sediments.
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BACKGROUND: Due to radical resection, endoprosthetic reconstruction (EPR) is more invasive and increases the risk of dislocation. Therefore, the suitability of EPR for elderly patients with metastatic tumor needs further investigation. METHODS: Seventy-one adult patients with isolated proximal femoral bone metastases who underwent EPR were retrospectively analyzed and stratified into two groups: elderly age group (≥60 years, n = 31) and younger age group (<60 years, n = 40). The effect of age on prognosis was analyzed to determine whether EPR is beneficial in elderly patients with proximal femoral metastatic tumor. Cox regression modeling was used to evaluate the effect of different factors on postoperative survival outcomes. RESULTS: Ten (32.26%) and 9 (22.50%) cases of perioperative complications were recorded in the elderly and younger age groups, respectively, with median survival times of 22.00 ± 4.61 months and 23.00 ± 2.85 months, respectively; a log-rank test showed that the difference was not statistically significant (p = 0.657). A Cox regression model was established with patient age as the covariable to evaluate whether it affected postoperative survival. The risk of death due to age was not significant (p = 0.649), but malignancy and femoral metastasis type were significantly associated with postoperative survival (p = 0.001 and p = 0.019). CONCLUSION: Although older patients have a slightly higher incidence of postoperative complications than younger patients, they do not experience severe adverse consequences. With rigorous selection and careful preparation, EPR is appropriate for the treatment of proximal femoral metastases in older patients, including those with Harrington type I-II acetabular invasion.
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Neoplasias Ósseas , Procedimentos de Cirurgia Plástica , Adulto , Humanos , Idoso , Pessoa de Meia-Idade , Lactente , Pré-Escolar , Estudos Retrospectivos , Fêmur/cirurgia , Fêmur/patologia , Neoplasias Ósseas/secundário , Extremidade Inferior/patologia , Resultado do TratamentoRESUMO
An aqueous suspension of WO3/poly(4-(2,3-dihydrothieno[3,4-b]-[1,4]dioxin-2-yl-methoxy)-1-butanesulfonic acid) (PEDTS) hybrid nanoparticles (NPs) is prepared by air-assisted oxidative polymerization and simultaneous attachment of PEDTS on WO3-NPs, and used for electrochromic (EC) film fabrication via air-brush spraying. The hybrid EC device exhibits enhanced EC properties compared to the ones based on WO3-NP or PEDTS alone.
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OBJECTIVE: To evaluate the photodynamic therapy (PDT) against multi-antibiotic-resistant Staphylococcus aureus (S. aureus) and Staphylococcus epidermidis (S.epidermidis) obtained from patients with chronic rhinosinusitis (CRS). METHODS: Forty-five CRS patients who had been given medical treatment but still needed endoscopic surgery were included in this study. The mucus from middle meatus was collected from these patients during surgery, followed by separation of S. aureus and S. epidermidis and drug sensitive test. The strains which could form biofilm were selected. Light emitting diode (LED) array with a major wavelength of (633±10) nm was used as light source and 5-Aminolevulinic acid (ALA) was used as photosensitizer in this PDT experiment. The safe range of LED dose and ALA concentration which were not toxic to bacteria by themselves were confirmed, and then did PDT experiment on S. aureus and S. epidermidis. The data of bacterial colony forming unit were transformed to lgCFU before statistical analysis.The Graph Pad Prism 5 software was used to analyzed the data. RESULTS: Thirteen S. aureus and 16 S. epidermidis were included in this experiment(from 45 patients), all of them were multi-antibiotic-resistant bacteria, and four of S. aureus and five of S. epidermidis could form biofilm in each group. In planktonic S. aureus experiment, the mean lgCFU was 8.32±0.31 in control group whereas the experiment group was 6.47±0.67 (t=9.01, P<0.01), and in planktonic S. epidermidis experiment the final data was 8.34±0.20 (control group) and 6.97±0.59 (experiment group) (t=8.84, P<0.01). In biofilm S. aureus experiment, the mean lgCFU was 8.68±0.05 (control group), 6.90±0.96(experiment group) (t=3.68, P<0.05); and in biofilm S. epidermidis experiment the data was 8.67±0.05 (control group), 7.29±0.61 (experiment group, t=5.07, P<0.01). CONCLUSION: Our results demonstrated that ALA-mediated PDT on multi-antibiotic-resistant S. aureus and S. epidermidis from CRS patients was effective in vitro. Additional work defining if the PDT treatment would damage the nasal mucosa and further checking the effectiveness of PDT in vivo is still needed.
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Farmacorresistência Bacteriana Múltipla , Fotoquimioterapia , Rinite/tratamento farmacológico , Sinusite/tratamento farmacológico , Infecções Estafilocócicas/tratamento farmacológico , Ácido Aminolevulínico/uso terapêutico , Antibacterianos , Biofilmes , Humanos , Luz , Fármacos Fotossensibilizantes/uso terapêutico , Rinite/microbiologia , Sinusite/microbiologia , Infecções Estafilocócicas/complicações , StaphylococcusRESUMO
An efficient process was designed for the synthesis of furfuryl alcohol and 2-methylfuran from xylose using a continuous fixed-bed reactor over a catalyst combining Hß zeolite and Cu/ZnO/Al2 O3 in γ-butyrolactone (GBL)/water as solvent. The cooperative effect of Hß zeolite and GBL facilitated the dehydration of xylose and enhanced largely the furfural yield. The production of furfuryl alcohol and 2-methylfuran can be simply tuned by changing the hydrogenation temperature for furfural over the Cu/ZnO/Al2 O3 catalyst. The yield for furfuryl alcohol reached 87.2 % at 150 °C whereas a yield of 86.8 % was achieved for 2-methylfuran at 190 °C.
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Furanos/química , Xilose/química , Catálise , TemperaturaRESUMO
Sodium butyrate (SB) has been widely used to treat cerebral diseases. The aim of the present study is to examine the neuroprotective effects of SB on early TBI in mice and to explore the underlying mechanisms of these effects. TBI was induced using a modified weight-drop method. Neurological deficits were evaluated according to the neurological severity score (NSS), brain oedema was measured by brain water content, and blood-brain barrier (BBB) permeability was evaluated by Evans blue (EB) dye extravasation. Neuronal injury was assessed by hematoxylin and eosin (H&E) staining and Fluoro-Jade C staining. The expression of tight junction-associated proteins, such as occludin and zonula occludens-1 (ZO-1), was analysed by western blotting and immunofluorescence. Our results showed that mice subjected to TBI exhibited worsened NSS, brain oedema, neuronal damage and BBB permeability. However, these were all attenuated by SB. Moreover, SB reversed the decrease in occludin and ZO-1 expression induced by TBI. These findings suggest that SB might attenuate neurological deficits, brain oedema, neuronal change and BBB damage, as well as increase occludin and ZO-1 expression in the brain to protect against TBI. The protective effect of SB may be correlated with restoring the BBB following its impairment.
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Barreira Hematoencefálica/efeitos dos fármacos , Lesões Encefálicas Traumáticas/metabolismo , Ácido Butírico/administração & dosagem , Neurônios/efeitos dos fármacos , Fármacos Neuroprotetores/administração & dosagem , Animais , Comportamento Animal/efeitos dos fármacos , Barreira Hematoencefálica/metabolismo , Edema Encefálico/metabolismo , Lesões Encefálicas Traumáticas/patologia , Lesões Encefálicas Traumáticas/prevenção & controle , Permeabilidade da Membrana Celular , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Neurônios/metabolismo , Ocludina/metabolismo , Proteína da Zônula de Oclusão-1/metabolismoRESUMO
One-step direct conversion of biomass-derived furfural to 2-methyltetrahydrofuran was realized under atmospheric pressure over a dual solid catalyst based on two-stage-packed Cu-Pd in a reactor; this is the first report that one-step conversion of furfural resulted in high yield of 2-methyltetrahydrofuran (97.1 %) under atmospheric pressure. This strategy provided a successive hydrogenation process, which avoids high H2 pressure, uses the reactor efficiently, and eliminates the product-separation step. Therefore, it could enhance the overall efficiency as a result of low cost and high yield.
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Furaldeído/química , Furanos/química , Catálise , Hidrogênio/química , HidrogenaçãoRESUMO
CONTEXT: Inflammation plays a critical role in the development and progression of obstructive sleep apnea (OSA). Lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1) activation is involved in the pathophysiology of inflammatory process-related disorders. OBJECTIVE: This study aims to investigate whether serum soluble LOX-1 (sLOX-1) levels are associated with the presence and severity of OSA. MATERIALS AND METHODS: A total of 137 OSA patients and 78 controls were recruited in this study. Serum sLOX-1 levels were measured by enzyme-linked immunosorbent assay. The severity of OSA was assessed by the apnea-hypopnea index (AHI). RESULTS: OSA patients had significantly higher serum sLOX-1 levels compared with controls. Serum sLOX-1 levels elevated with the increment of OSA severity. sLOX-1 was the independent predictor of OSA. Serum sLOX-1 levels were significantly correlated with AHI and high-sensitivity C-reactive protein levels. CONCLUSIONS: Serum sLOX-1 levels were independently correlated with the presence and severity of OSA. These findings revealed that sLOX-1 might function as a potential biomarker for monitoring the development and progression of OSA.
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Receptores Depuradores Classe E/sangue , Apneia Obstrutiva do Sono/sangue , Idoso , Biomarcadores/sangue , Proteína C-Reativa/metabolismo , Estudos de Casos e Controles , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Inflamação/sangue , Masculino , Pessoa de Meia-Idade , Síndromes da Apneia do Sono/sangueRESUMO
OBJECTIVE: The purpose of this study was to determine the optimal operative approach for the treatment of spinal tuberculosis. We analyzed two types of pathological vertebrae (thoracic and lumbar) and three cardinal operative approaches for surgery. METHODS: Sixty patients with spinal tuberculosis were divided into thoracic (n=30) and lumbar groups (n=30) based on locations of the foci. These patients underwent anti-tuberculosis drug and surgical therapy. The operative approaches for the surgical treatments were the anterior approach (AA, n=20), posterior approach (PA, n=20), and combined anterior and posterior approach (CAPA, n=20). All clinical data from the patients was collected and included surgical time, blood loss, correction of kyphosis, and vertebral body height reconstruction. Differences in the means between the groups were evaluated statistically with one-way analyses of variance (ANOVAs). RESULTS: The surgery time in the CAPA group was longer than that of AA group (P<0.05), and there were no significant differences between the CAPA and PA groups or the AA and PA groups. The average vertebral body height reconstruction in the AA group was larger than that of the PA or CAPA groups, and there was no significant difference between the PA and CAPA groups (P>0.05). There were no interactions between the location of the pathological vertebra and the type of surgical approach, with the exception of blood loss. The blood loss of the CAPA was greater than those of the AA and PA patients in the thoracic group (P<0.05), and no significant difference was found in the lumbar group (P>0.05). CONCLUSIONS: AA was well-suited for serious vertebral collapse that required reconstruction of the height of the vertebrae. CAPA was unfit for patients with poor basic conditions due to the long surgical time, but the long surgery time of CAPA did not necessarily lead to greater blood loss compared to the other approaches.
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Vértebras Lombares/cirurgia , Procedimentos Ortopédicos/métodos , Vértebras Torácicas/cirurgia , Tuberculose da Coluna Vertebral/cirurgia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Humanos , Vértebras Lombares/patologia , Masculino , Pessoa de Meia-Idade , Procedimentos Ortopédicos/normas , Vértebras Torácicas/patologia , Resultado do Tratamento , Tuberculose da Coluna Vertebral/patologia , Adulto JovemRESUMO
Sinonasal Rosai-Dorfman disease (S-RDD) is a rare form of RDD limited to the sinonasal cavity. Multipatient studies of Chinese S-RDD and documentation of its clinical spectrum are rare. This study aimed to identify the clinical profiles of Chinese S-RDD. Medical records of and tissue sections from 10 patients diagnosed with S-RDD between 2007 and 2014 were reviewed. Data on clinical presentations, endoscopy signs, imageological change, treatment and outcome were analyzed. The mean age of five male and five female patients at the first visit was 40.3 years and the mean follow-up period was 58.6 months. Based on the lesion sites, five cases were divided into an anterior sinonasal group, accompanied by symptoms of epistaxis, nasal obstruction and nasal dorsal deformity. Five other cases were divided into a posterior sinonasal group, accompanied by symptoms of hyposmia, epistaxis and nasal obstruction. Endoscopy signs and imageological changes in the anterior group showed diffuse infiltration of the RDD lesion under the septum mucosa, but in the posterior group the RDD lesions often showed as formations on polyps. At the end of follow-up, only one case spontaneously resolved without surgery; two cases in the anterior sinonasal group and three cases in the posterior sinonasal group recurred after endoscopic surgery, but surgery can result in short-term symptomatic control and restoration of function in all cases. S-RDD of the anterior and posterior sinonasal cavity may have different clinical characteristics; endoscopic surgery is effective for short-term symptomatic control and restoration of function for S-RDD.
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Histiocitose Sinusal/cirurgia , Doenças Nasais/cirurgia , Doenças dos Seios Paranasais/cirurgia , Adolescente , Adulto , Endoscopia , Epistaxe/etiologia , Feminino , Seguimentos , Histiocitose Sinusal/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade , Cavidade Nasal/cirurgia , Obstrução Nasal/etiologia , Septo Nasal/cirurgia , Doenças Nasais/diagnóstico , Doenças dos Seios Paranasais/diagnóstico , Recidiva , Estudos Retrospectivos , Adulto JovemRESUMO
An electrofluorochromic (EFC) conjugated copolymer (PEFC) containing carbazole and benzothiadiazole (BTD) moieties is synthesized through Suzuki coupling followed by electrochemical polymerization, resulting in a nanoporous EFC polymer electrode. The electrode exhibits high sensitivity and selectivity in the EFC detection of cyanide anions (CN(-)) in largely aqueous electrolyte (67â vol % water) because electrochemical oxidation of PEFC leads to significant fluorescence quenching, and the presence of different concentrations (1 to 100â µM) of CN(-) in the electrolyte can weaken the oxidative quenching to substantially different extents. Although PEFC is hydrophobic in the neutral state, it is converted to radical cation/dication states upon oxidation, rendering the PEFC some hydrophilicity. Moreover, its nanoporous morphology provides a large surface area and short diffusion distance, facilitating the movement of CN(-) in the electrolyte into the PEFC film to interact with receptors. Density functional theory calculations show that the noncovalent interaction between electron-deficient BTD and nucleophilic CN(-) is energy favorable in the oxidized states in both aqueous and organic media, suggesting that the specific π(-)-π(+) interaction plays the main role in the CN(-) detection.
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microRNAs constitute a novel class of small, non-coding RNAs that negatively regulate gene expression via translational inhibition or mRNA degradation. Aberrant miRNA expression has been implicated in the initiation, progression, and metastasis of hepatocellular carcinoma (HCC). It is well-documented that miRNAs function as either tumor suppressor genes or oncogenes in the development and progression of HCC. Additionally, substantial evidence suggests that unique miRNA signatures can serve as valuable diagnostic and prognostic biomarkers for HCC. Interestingly, certain subsets of miRNAs have also been identified as potential therapeutic targets for HCC.
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Biomarcadores/metabolismo , Carcinoma Hepatocelular/diagnóstico , Regulação Neoplásica da Expressão Gênica/fisiologia , Neoplasias Hepáticas/diagnóstico , MicroRNAs/metabolismo , Humanos , MicroRNAs/genéticaRESUMO
A rapid, sensitive and reliable liquid chromatography-tandem mass spectrometry method was developed and validated for the determination of betulonic acid in rat plasma. The plasma samples were prepared by protein precipitation. Chromatographic separation was achieved on an Agela MG-C18 analytical column (50 × 2.1 mm, 5 µm) using methanol-water-formic acid (80:20:0.1, v/v/v) as the mobile phase with a constant flow rate of 0.6 mL/min. Mass detection was conducted by electrospray ionization in positive ion multiple reaction monitoring mode. The calibration curves were linear over a concentration range of 3.00-3,000 ng/mL for the analyte. The intra-day and inter-day accuracy and precision were within the acceptable limits of ±15% at all concentrations. The method was successfully applied for the estimation of betulonic acid in rat plasma from a preclinical pharmacokinetics study.
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Cromatografia Líquida/métodos , Ácido Oleanólico/análogos & derivados , Espectrometria de Massas em Tandem/métodos , Animais , Estabilidade de Medicamentos , Liquidambar/química , Masculino , Ácido Oleanólico/sangue , Ácido Oleanólico/química , Ácido Oleanólico/farmacocinética , Ratos , Ratos Sprague-Dawley , Reprodutibilidade dos Testes , Sensibilidade e EspecificidadeRESUMO
Selective detection of cyanide anions is realized via electrofluorochromism of a benzothiadiazole-containing conjugated copolymer because oxidative fluorescence quenching induced by positive potentials can be significantly weakened by interaction between nucleophilic cyanide and electron-deficient benzothiadiazole.
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A series of solvent-free ionic liquid (IL)-based polymer electrolytes composed of amorphous and biodegradable poly(propylene carbonate) (PPC) host, LiClO4, and 1-butyl-3-methylimidazolium tetrafluoroborate (BMIM(+)BF4(-)) were prepared and characterized for the first time. FTIR studies reveal that the interaction between PPC chains and imidazolium cations weakens the complexation between PPC chains and Li(+) ions. Thermal analysis (DSC and TGA) results show that the incorporation of BMIM(+)BF4(-) into PPC/LiClO4 remarkably decreases the glass transition temperature and improves the thermal stability of the electrolytes. AC impedance results show that the ionic conductivities of the electrolytes are significantly increased with the increase of BMIM(+)BF4(-) amount, the ambient ionic conductivity of the electrolyte at a PPC/LiClO4/BMIM(+)BF4(-) weight ratio of 1/0.2/3 is 1.5 mS/cm, and the ionic transport behavior follows the Arrhenius equation. Both PPC/LiClO4/BMIM(+)BF4(-) and PPC/BMIM(+)BF4(-) electrolytes were applied in electrochromic devices with polyaniline as the electrochromic layer. The PPC/LiClO4/BMIM(+)BF4(-)-based device exhibits much better electrochromic performance in terms of optical contrast and switching time due to the presence of much smaller cations.
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OBJECTIVES: Lysophosphatidic acid (LPA) is a bioactive lipid mediator involved in tumour progression, cell invasion and metastasis. The mechanism of action of LPA in the invasive and metastatic capacity of human hepatocellular carcinoma (HCC) is not fully understood. This study investigated the effects of LPA on HCC cell invasion and induction of matrix metalloproteinase (MMP) -2 and -9. METHODS: LPA receptor levels in HCC cell lines were detected by Western blot analysis; HCC cell invasion was analysed by the Transwell® system. The LPA receptor blocker Ki16425 was used to determine whether HCC cell invasion was LPA dependent. Expression of the MMP2 and MMP9 genes in HCC cells was determined by real-time quantitative reverse transcription-polymerase chain reaction (qPCR). RESULTS: LPA increased HCC cell invasion, which was LPA-receptor dependent. Real-time RT-qPCR showed that LPA increased MMP9, but not MMP2, expression in HCC cells. Pharmacological inhibition of LPA receptors with Ki16452 significantly attenuated LPA-induced HCC cell invasion. CONCLUSIONS: HCC invasiveness is facilitated by LPA and may be relevant to tumour progression. Thus, LPA receptors may be a potential therapeutic target for HCC.
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Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Receptores de Ácidos Lisofosfatídicos/metabolismo , Western Blotting , Carcinoma Hepatocelular/enzimologia , Carcinoma Hepatocelular/genética , Linhagem Celular Tumoral , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Neoplasias Hepáticas/enzimologia , Neoplasias Hepáticas/genética , Lisofosfolipídeos/farmacologia , Metaloproteinase 2 da Matriz/genética , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/genética , Metaloproteinase 9 da Matriz/metabolismo , Invasividade Neoplásica , Receptores de Ácidos Lisofosfatídicos/antagonistas & inibidoresRESUMO
Azulene-containing conjugated polymers with near-infrared absorption up to 1.5 µm and beyond are achieved by treating with trifluoroacetic acid (TFA). Density functional theory calculations reveal that the near-infrared absorption arises from a strong intramolecular charge transfer transition on the polymer backbone, and the near-infrared absorption can be tuned by the degree of protonation. Furthermore, TFA treated polymers show a ten-fold enhancement in electrochromic contrast and significantly improved switching stability, suggesting that these polymers are promising candidates for fabrication of the first generation organic near-infrared devices.
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2α, 3α, 24-Trihydroxyurs-12-en-28-oic acid (TEOA) is a prominent ursane-type triterpenoid isolated from the root of Actinidia deliciosa, which has numerous pharmacological activities. To date, there is no report on the pharmacokinetic characterization of TEOA in biological samples. A specific, sensitive and robust liquid chromatography-tandem mass spectrometry (LC-MS-MS) method is reported for the fast assay of TEOA in rat plasma. Plasma sample preparation was based on liquid-liquid extraction with ethyl acetate. The extracted samples were determined using LC-MS-MS coupled with an atmospheric-pressure chemical ionization source in multiple-reaction monitoring scan mode. Chromatographic separation was achieved on a C18 Capcell PAK UG120 column (100 × 4.6 mm, i.d., 5 µm) using an isocratic elution mode with a total running time of 2.8 min. The selected ion pairs m/z 471.3 â 203.1 for the analyte and m/z 309.2 â 163.1 for internal standard were monitored in positive ionization mode for MS-MS detection. This method has been fully validated and the results showed good linearity, precision, accuracy and recovery. A stability test was conducted under various sample preparation, analysis and storage conditions. The method was successfully applied for the pharmacokinetic study of TEOA in rat plasma after oral administration of 100 mg/kg TEOA.