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1.
Nutr Cancer ; 76(1): 89-97, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37979150

RESUMO

We aimed to explore the association between the serum 25-hydroxyvitamin D concentration and all-cause and cancer-specific mortality in 2,463 adult patients with cancer from the National Health and Nutrition Examination Survey 2007-2018. We linked mortality data from the survey to the National Death Index records up to December 31, 2019. During a median follow-up period of 70 months, 567 patients died, of whom 194 died due to cancer. Multivariate adjustment was performed for demographic characteristics, lifestyle, dietary factors, 25-hydroxyvitamin D testing period, and cancer site. Higher serum 25-hydroxyvitamin D concentrations up to 75 nmol/L significantly reduced the risk of all-cause and cancer-specific mortality. When 25-hydroxyvitamin D quartiles were compared, the multivariable-adjusted hazard ratios were 0.59 (95% confidence interval: 0.42, 0.84) for all-cause mortality (P for trend <0.001) and 0.48 (95% confidence interval: 0.29, 0.79) for cancer-specific mortality (P for trend = 0.037) in quartile 3 (79.3-99.2 nmol/L). A threshold of 75 nmol/L for serum 25-hydroxyvitamin D may represent an intervention target to reduce mortalities in patients with cancer, and maintaining 25(OH)D concentrations within range (79.3-99.2 nmol/L) is beneficial for reducing all-cause and cancer-specific mortality.


Assuntos
Doenças Cardiovasculares , Neoplasias , Deficiência de Vitamina D , Adulto , Humanos , Inquéritos Nutricionais , Vitamina D , Vitaminas , Calcifediol , Fatores de Risco
2.
ACS Nano ; 17(22): 23103-23114, 2023 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-37930125

RESUMO

Rare earth (RE) elements possess electronic configurations that can provide additional pathways for tailoring the electronic structures of active elements through alloying, making it an important area of exploration in electrocatalysis. However, the large negative redox potential between RE and Pt has hindered the development of RE nanoalloys. In this study, a solid-phase synthesis strategy was employed to synthesize ternary Pt3-xIrxSc nanoparticles (NPs). By leveraging the electronegativity difference between Pt (2.28), Ir (2.20), and Sc (1.36), a charge-balance strategy was implemented to stabilize and enhance the catalytic performance of the alloy. The electron transfer from Sc to Pt/Ir results in the latter being negatively charged, and the Ir modifies the electron density of Pt, enabling favorable adsorption of active H species during the hydrogen evolution reaction (HER). Pt2IrSc exhibits enhanced HER activity at all pH values, achieving low overpotentials at 10 mA cm-2 of only 13, 18, and 25 mV in 0.5 M H2SO4, 1 M PBS, and 1 M KOH, respectively. This electrocatalyst also exhibits robust electrocatalytic stability even after 20,000 cycles. This work represents an application of the charge balance strategy to RE nanoalloys, and it is expected to inspire the design and synthesis of highly reactive RE nanoalloys.

3.
Nutr Cancer ; 75(5): 1340-1348, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36988095

RESUMO

Vitamin D (VD) plays a regulatory role in tumor occurrence and development, although the factors influencing serum 25-hydroxyvitamin D3 (25(OH)D3) levels in patients with cancer have not been studied. Therefore, we aimed to evaluate circulating levels of 25(OH)D3 and factors influencing the VD status in patients with malignant tumors. Adult patients with malignant tumors who had undergone assessments of serum 25(OH)D3 at Beijing Cancer Hospital from January 2019 to July 2022 were included. A multiple logistic regression model was applied to explore the associations of patient characteristics, environment, and disease characteristics with 25(OH)D3 levels. Among the 1,076 included patients, the median 25(OH)D3 serum concentration was 16.25 ng/mL. VD deficiency and the combined VD insufficiency and sufficiency were observed in 811 (75.37%) and 265 (24.63%) patients, respectively. Latitude, season, sex, body mass index, and type of cancer were associated with VD concentration/status in patients with malignant tumors. 25(OH)D3 concentrations were significantly higher in patients with thyroid cancer and significantly lower in patients receiving tumor-related treatment than in untreated patients. Surprisingly, we observed 25(OH)D3 serum concentration was lower in patients receiving nutritional supplementation than in those receiving no nutritional supplements. Patients with malignant tumors are at high risk of VD deficiency.


Assuntos
Neoplasias da Glândula Tireoide , Deficiência de Vitamina D , Adulto , Humanos , Vitamina D , Vitaminas , Calcifediol , Suplementos Nutricionais
4.
Biomed Chromatogr ; 33(1): e4387, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30238479

RESUMO

Determination of amino acids in biofluids is a challenging task because of difficulties deriving from their high polarity and matrix interference. A simple, reliable and high-throughput hydrophilic interaction UHPLC-MS/MS method was developed and validated for the rapid simultaneous determination of 19 free amino acids in rat plasma and urine samples in this paper. Hydrophilic method with a Waters Acquity UPLC BEH Amide column (100 × 2.1 mm,1.7 µm) was used with a gradient mobile phase system of acetonitrile and water both containing 0.2% formic acid. The analysis was performed on a positive electrospray ionization mass spectrometer via multiple reaction monitoring. Samples of 10 µL plasma and 50 µL urine were spiked with three deuterated internal standards, pretreated with 250 µL acetonitrile for one-step protein precipitation and a final dilution of urine samples. Good linearities (r > 0.99) were obtained for all of the analytes with the lower limit of quantification from 0.1 to 1.2 µg/mL. The relative standard deviation of the intra-day and inter-day precisions were within 15.0% and the accuracy ranged from -12.8 to 12.7%. The hydrophilic interaction UHPLC-MS/MS method was rapid, accurate and high-throughput and exhibited better chromatography behaviors than the regular RPLC methods. It was further successfully applied to detect 19 free amino acids in biological matrix.


Assuntos
Aminoácidos/sangue , Aminoácidos/urina , Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas em Tandem/métodos , Aminoácidos/química , Animais , Interações Hidrofóbicas e Hidrofílicas , Limite de Detecção , Modelos Lineares , Masculino , Ratos , Ratos Sprague-Dawley , Reprodutibilidade dos Testes
5.
Biomed Chromatogr ; 33(4): e4456, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30536598

RESUMO

A rapid, selective and sensitive ultra-high-performance liquid chromatography-tandem mass spectrometry method was developed to simultaneously determine oxybutynin and its active metabolite N-desethyl oxybutynin in rat plasma. A 0.1 mL sample of plasma was extracted with n-hexane. Chromatographic separation was performed on a UPLC BEH C18 column (2.1 × 100 mm i.d.,1.7 µm) with mobile phase of methanol-water (containing 2 mmol/L ammonium acetate and 0.1% formic acid; 90:10, v/v). The detection was performed in positive selected reaction monitoring mode. Each plasma sample was chromatographed within 3 min. The linear calibration curves were obtained in the concentration range of 0.0944-189 ng/mL (r ≥ 0.99) for oxybutynin and 0.226-18.0 ng/mL (r ≥ 0.99) for N-desethyl oxybutynin. The intra- and inter-day precision (relative standard deviation) values were not more than 14% and the accuracy (relative error) was within ±7.6%. The method described was superior to previous methods for the quantitation of oxybutynin with three product ions and was successfully applied to a pharmacokinetic study of oxybutynin and its active metabolite N-desethyl oxybutynin in rat plasma after transdermal administration.


Assuntos
Ácidos Mandélicos/sangue , Ácidos Mandélicos/farmacocinética , Adesivo Transdérmico , Animais , Cromatografia Líquida de Alta Pressão/métodos , Limite de Detecção , Modelos Lineares , Masculino , Ácidos Mandélicos/administração & dosagem , Ácidos Mandélicos/química , Ratos , Ratos Wistar , Reprodutibilidade dos Testes , Espectrometria de Massas em Tandem/métodos
6.
Artigo em Inglês | MEDLINE | ID: mdl-29132024

RESUMO

A HILIC-UHPLC-MS/MS untargeted urinary metabonomic method combined with quantitative analysis of five potential polar biomarkers in rat urine was developed and validated, to further understand the anti-osteoporosis effect of Gushudan(GSD) and its mechanism on prednisolone-induced osteoporosis(OP) rats in this study. The metabolites were separated and identified on Waters BEH HILIC (2.1mm×100mm, 1.7µm) column using the Waters ACQUITY™ ultra performance liquid chromatography system (Waters Corporation, Milford, USA) coupled with a Micromass Quattro Micro™ API mass spectrometer (Waters Corp, Milford, MA, USA). Principal component analysis (PCA) was used to identify potential biomarkers. Primary potential polar biomarkers including creatinine, taurine, betaine, hypoxanthine and cytosine, which were related to energy metabolism, lipid metabolism and amino acid metabolism, were found in the untargeted metabonomic research. Moreover, these targeted biomarkers were further separated and quantified in multiple-reaction monitoring (MRM) with positive ionization mode, using tinidazole as internal standard (I.S.). Good linearities (r>0.99) were obtained for all the analytes with the low limit of quantification from 1.00 to 12.8µg/mL. The relative standard deviation (RSD) of the intra-day and inter-day precisions were within 15.0% and the accuracy ranged from -14.3% to 13.5%. The recovery was more than 85.0%. And the validated method was successfully applied to investigate the urine samples of the control group, prednisolone-induced osteoporosis model group and Gushudan-treatment group in rats. Compared to the control group, the level of creatinine, taurine, betaine, hypoxanthine and cytosine in the model group revealed a significant decrease trend (p<0.05), while the Gushudan-treatment group showed no statistically differences by an independent sample t-test. This paper provided a better understanding of the therapeutic effect and mechanism of GSD on prednisolone-induced osteoporosis rats.


Assuntos
Biomarcadores/urina , Cromatografia Líquida de Alta Pressão/métodos , Medicamentos de Ervas Chinesas/farmacologia , Metaboloma/efeitos dos fármacos , Metabolômica/métodos , Espectrometria de Massas em Tandem/métodos , Administração Oral , Animais , Biomarcadores/metabolismo , Medicamentos de Ervas Chinesas/administração & dosagem , Medicamentos de Ervas Chinesas/farmacocinética , Limite de Detecção , Modelos Lineares , Masculino , Análise de Componente Principal , Ratos , Ratos Wistar , Reprodutibilidade dos Testes
7.
Biomed Chromatogr ; 32(2)2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28718960

RESUMO

In this paper, an ultra high performance liquid chromatography tandem mass spectrometric (UPLC-ESI-MS/MS) method in positive ion mode was established to systematically identify and to compare the major aconitum alkaloids and their metabolites in rat plasma and urine after oral administration of Fuzi extract. A total twenty-nine components including twenty-five C19-diterpenoid alkaloids and four C20-diterpenoid alkaloids were identified in Fuzi extract. Thirteen of the parent components and five metabolites were detected in rat plasma and sixteen parent compounds and six metabolites in urine. These parent components found in rat plasma and urine were mainly C19-diterpenoid alkaloids. All of the metabolites in vivo were demethylated metabolites (phase I metabolites), which suggested that demethylation was the major metabolic pathway of aconitum alkaloids in vivo. A comparison of the parent components in rat plasma and urine revealed that 3-deoxyacontine was found in plasma but not in urine, while kalacolidine, senbusine and 16-ß-hydroxycardiopetaline existed in urine but not in plasma, which indicated that most alkaloids components were disposed and excreted in prototype form. This research provides some important information for further metabolic investigations of Fuzi in vivo.


Assuntos
Aconitum/química , Alcaloides/sangue , Alcaloides/urina , Extratos Vegetais/farmacocinética , Administração Oral , Alcaloides/química , Alcaloides/farmacocinética , Animais , Cromatografia Líquida de Alta Pressão/métodos , Diterpenos , Medicamentos de Ervas Chinesas , Masculino , Extratos Vegetais/administração & dosagem , Raízes de Plantas/química , Ratos , Ratos Sprague-Dawley , Espectrometria de Massas em Tandem/métodos
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