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1.
Angew Chem Int Ed Engl ; 62(32): e202307490, 2023 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-37318956

RESUMO

Photocatalytic hydrogen (H2 ) production is significant to overcome challenges like fossil fuel depletion and carbon dioxide emission, but its efficiency is still far below that which is needed for commercialization. Herein, we achieve long-term stable H2 bubbling production from water (H2 O) and lactic acid via visible-light-driven photocatalysis in a porous microreactor (PP12); the catalytic system benefits from photocatalyst dispersion, charge separation, mass transfer, and dissociation of O-H bonds associated with H2 O. With the widely used platinum/cadmium-sulfide (Pt/CdS) photocatalyst, PP12 leads to a H2 bubbling production rate of 602.5 mmol h-1 m-2 , which is 1000 times higher than that in a traditional reactor. Even when amplifying PP12 into a flat-plate reactor with an area as large as 1 m2 and extending the reaction time to 100 h, the H2 bubbling production rate still remains at around 600.0 mmol h-1 m-2 , offering great potential for commercialization.

2.
Biomed Chromatogr ; 33(3): e4426, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30408206

RESUMO

The pharmacokinetics of R-(-)ondansetron (R-ond) compared with that of S-(-)ondansetron (S-ond) was studied in rats. R-ond and S-ond were injected intravenously into rats at a dose of 2.0 mg/kg. The stability of ondansetron enantiomers in rat was determined by chiral HPLC, and the concentrations of R-ond and S-ond in plasma were determined by an LC/MS/MS method. The pharmacokinetic parameters were calculated and analyzed statistically using the t-test. The enantiomer inversions between R-ond and S-ond did not occur in rat. The pharmacokinetic parameters (t1/2 , AUC, MRT, CL) of R-ond and S-ond differed significantly. The concentration in plasma of the R/S-enantiomeric ratio reached a maximum value of 9.5 at 4.0 h post-dose. The pharmacokinetics of R-ond and S-ond are stereoselective in rat, which indicates substantial stereoselectivity in the disposition of ondansetron enantiomers in rat. R-ond has more potential than S-ond to be developed as a single enantiomer drug.


Assuntos
Cromatografia Líquida/métodos , Ondansetron/sangue , Ondansetron/farmacocinética , Espectrometria de Massas em Tandem/métodos , Animais , Feminino , Modelos Lineares , Masculino , Ondansetron/química , Distribuição Aleatória , Ratos , Ratos Wistar , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Estereoisomerismo
3.
Biomed Chromatogr ; 33(10): e4618, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31174234

RESUMO

Ondansetron, a 5-hydroxytryptamine type 3 (5-HT3 ) receptor antagonist, is regarded as an excellent candidate to treat chemotherapy- and radiotherapy-induced nausea and vomiting. To better understand the metabolic profiles of ondansetron in human urine, the metabolites were analyzed using liquid chromatography/mass spectrometry (LC/MSn ). Urine samples were collected after oral administration of 8 mg ondansetron to healthy volunteers. Then samples were treated by solid-phase extraction and detected with LC/MSn . Besides ondansetron, in human urine, a total of 19 metabolites including 13 new metabolites were detected and identified via comparing the retention time and product ion spectra with those of reference standards isolated and characterized. The results showed that ondansetron was metabolized via hydroxylation, glucuronidation, sulfation and minor N-demethylation in human. LC/MSn was demonstrated to be useful and sensitive in the metabolic study of ondansetron.


Assuntos
Cromatografia Líquida/métodos , Ondansetron , Espectrometria de Massas em Tandem/métodos , Adulto , Humanos , Masculino , Modelos Moleculares , Ondansetron/química , Ondansetron/metabolismo , Ondansetron/urina , Extração em Fase Sólida , Adulto Jovem
4.
Food Funct ; 2024 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-39073342

RESUMO

Caffeine, a controversial substance, was once known to be addictive and harmful. In recent years, new effects of caffeine on the human body have been confirmed. Recent research over the past few decades has shown the potential of caffeine in treating pancreas-related diseases. This review aims to analyze the known and possible mechanisms of caffeine on pancreatic diseases and provides an overview of the current research status regarding the correlation between caffeine and pancreatic disease, while enhancing our understanding of their relationship.

5.
World J Gastrointest Oncol ; 16(3): 1059-1075, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38577469

RESUMO

BACKGROUND: Glycosylation, a commonly occurring post-translational modification, is highly expressed in several tumors, specifically in those of the digestive system, and plays a role in various cellular pathophysiological mechanisms. Although the importance and detection methods of glycosylation in digestive system tumors have garnered increasing attention in recent years, bibliometric analysis of this field remains scarce. The present study aims to identify the developmental trends and research hotspots of glycosylation in digestive system tumors. AIM: To find and identify the developmental trends and research hotspots of glycosylation in digestive system tumors. METHODS: We obtained relevant literature from the Web of Science Core Collection and employed VOSviewer 1.6.19 and CiteSpace (version 6.1.R6) to perform bibliometric analysis. RESULTS: A total of 2042 documents spanning from 1978 to the present were analyzed, with the research process divided into three phases: the period of obscurity (1978-1990), continuous development period (1991-2006), and the rapid outbreak period (2007-2023). These documents were authored by researchers from 66 countries or regions, with the United States and China leading in terms of publication output. Reis Celso A had the highest number of publications, while Pinho SS was the most cited author. Co-occurrence analysis revealed the most popular keywords in this field are glycosylation, expression, cancer, colorectal cancer, and pancreatic cancer. Furthermore, the Journal of Proteome Research was the most prolific journal in terms of publications, while the Journal of Biological Chemistry had the most citations. CONCLUSION: The bibliometric analysis shows current research focus is primarily on basic research in this field. However, future research should aim to utilize glycosylation as a target for treating tumor patients.

6.
Adv Sci (Weinh) ; 11(22): e2400250, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38554396

RESUMO

Porous materials with sound absorption and load-bearing capabilities are in demand in engineering fields like aviation and rail transportation. However, achieving both properties simultaneously is challenging due to the trade-off between interconnected pores for sound absorption and mechanical strength. Inspired by quilling art, a novel design using spiral material formed by rolling planar materials into helical structures is proposed. Experimental results show high structural strength through self-locking mechanisms, while double porosities from interlayer spiral slits and aligned submillimeter pores provide excellent sound absorption. These spiral sheets surpass foam aluminum in specific strength (up to 5.1 MPa) and approach aerogels in sound absorption (average coefficient of 0.93 within 0-6400 Hz). With its adaptability to various planar materials, this spiral design allows for hybrid combinations of different materials for multi-functionality, paving the way for designing advanced, lightweight porous materials for broad applications.

7.
Phys Rev E ; 107(2-1): 024502, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36932574

RESUMO

Salt concentration and confinement effects affect the configuration of polyelectrolyte (PE) brushes due to electrostatic interactions. In this work, we develop a new theoretical model to analyze the electrostatics and swelling-shrinking behavior of two opposing PE brushes. By comparing three length scales, i.e., equilibrium brush height, separation distance, and Debye length, we obtain distinct scaling laws for brush height in different regimes. We provide explanations for the anomalous shrinkage of the PE brush with added salt reported in experiments and simulations, the applicability of the homogeneous brush assumption, and the confinement effect on the brush height. Our model can be used to shed light on the configuration and functionalities of PE-grafted interfaces, which play important roles in ion selective membranes and organism lubrication. We also anticipate that our method will be useful to understand the functionalities of other charged soft matter systems, such as hydrogel swelling and colloidal stability.

8.
Sci Rep ; 13(1): 20535, 2023 11 23.
Artigo em Inglês | MEDLINE | ID: mdl-37996510

RESUMO

A multi-class classification model for acute coronary syndrome (ACS) remains to be constructed based on multi-fluid metabolomics. Major confounders may exert spurious effects on the relationship between metabolism and ACS. The study aims to identify an independent biomarker panel for the multiclassification of HC, UA, and AMI by integrating serum and urinary metabolomics. We performed a liquid chromatography-tandem mass spectrometry (LC-MS/MS)-based metabolomics study on 300 serum and urine samples from 44 patients with unstable angina (UA), 77 with acute myocardial infarction (AMI), and 29 healthy controls (HC). Multinomial machine learning approaches, including multinomial adaptive least absolute shrinkage and selection operator (LASSO) regression and random forest (RF), and assessment of the confounders were applied to integrate a multi-class classification biomarker panel for HC, UA and AMI. Different metabolic landscapes were portrayed during the transition from HC to UA and then to AMI. Glycerophospholipid metabolism and arginine biosynthesis were predominant during the progression from HC to UA and then to AMI. The multiclass metabolic diagnostic model (MDM) dependent on ACS, including 2-ketobutyric acid, LysoPC(18:2(9Z,12Z)), argininosuccinic acid, and cyclic GMP, demarcated HC, UA, and AMI, providing a C-index of 0.84 (HC vs. UA), 0.98 (HC vs. AMI), and 0.89 (UA vs. AMI). The diagnostic value of MDM largely derives from the contribution of 2-ketobutyric acid, and LysoPC(18:2(9Z,12Z)) in serum. Higher 2-ketobutyric acid and cyclic GMP levels were positively correlated with ACS risk and atherosclerosis plaque burden, while LysoPC(18:2(9Z,12Z)) and argininosuccinic acid showed the reverse relationship. An independent multiclass biomarker panel for HC, UA, and AMI was constructed using the multinomial machine learning methods based on serum and urinary metabolite signatures.


Assuntos
Síndrome Coronariana Aguda , Infarto do Miocárdio , Humanos , Síndrome Coronariana Aguda/diagnóstico , Ácido Argininossuccínico , Cromatografia Líquida , Espectrometria de Massas em Tandem , Biomarcadores , Infarto do Miocárdio/diagnóstico , Angina Instável , GMP Cíclico
9.
Heliyon ; 9(9): e19801, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37809417

RESUMO

Ferroptosis is a form of regulated cell death that was first formally proposed a decade ago. While its role in cancer cell death was initially understudied, it has recently gained considerable interest from researchers. In recent years, a growing number of studies have focused on the role of ferroptosis in cancer progression, with the goal of developing novel ferroptosis-inducing cancer therapies. This study aims to present the developmental trend and hotspots of research on ferroptosis-inducing cancer therapy using bibliometric analysis. A literature search was conducted using the Web of Science Core Collection on October 1st, 2022, to retrieve articles and reviews pertaining to ferroptosis and cancer published from 2012 to 2022. Microsoft Excel 2016, VOSviewer 1.6.18 and CiteSpace (version 6.1. R6) were utilized to conduct the bibliometric analysis of publication trends, authorship, and citation networks, with a focus on identifying countries, institutions, journals, and authors contributing to the field. These analyses were used to predict future trends in this area. A total of 2839 articles were identified and extracted for analysis. The number of publications has increased almost every year, with a sharp increase after 2018. China produced the most publications in this area, followed by the United States. Central South University was the institution that published the most papers. Frontiers in Oncology was the journal with the highest number of publications, while Cell had the greatest impact factor. Daolin Tang was the most productive author and Dixon SJ was the most influential author. Co-occurrence and burst analyses of keywords and references were conducted to identify the developmental trends and hotspots in ferroptosis-inducing cancer therapy research. Main research directions have shifted from investigating the mechanism of ferroptosis to developing novel ferroptosis-targeting cancer therapies. Emerging topicsfocus on the role of ferroptosis in solid tumor therapy. Based on our bibliometric analysis, we predict that research on ferroptosis in cancer therapy will continue to be a hot topic in the future, with a growing number of treatment modalities related to ferroptosis being developed. Our study provides valuable insights into the current state and future trends of research in this field, serving as a useful guide for researchers seeking to make important contributions in this area.

10.
Food Chem ; 344: 128681, 2021 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-33279349

RESUMO

Fermentation with excellent aroma-producing yeasts can enhance the flavour of soy sauce. In this work, Millerozyma farinosa CS2.23, Zygosaccharomyces rouxii CS2.42, and Candida parapsilosis CS2.53 were added to the high-salt liquid-state moromi to promote soy sauce fermentation. All three yeasts improved the TE of soy sauce, the highest of which reached 1.03 g/L with added CS2.42. Other quality indexes of soy sauce, including RS, TA, and AN, were not greatly affected. The volatile esters of soy sauce added to the three yeasts increased by 108.85%, 166.71%, and 113.61% compared with the control through GC-MS analysis. Obviously, CS2.42 had an excellent ability to produce esters. Studying the biosynthesis pathway of esters, CS2.42 has the best esterification ability, while CS2.53 has the advantage of alcoholysis ability. The exploration of the biosynthetic pathway of acetate and ethyl esters has laid a foundation for regulating esters in soy sauce fermentation.


Assuntos
Ésteres/química , Ésteres/metabolismo , Fermentação/efeitos dos fármacos , Odorantes/análise , Cloreto de Sódio/farmacologia , Alimentos de Soja/microbiologia , Leveduras/metabolismo , Paladar
11.
Hepatol Int ; 15(5): 1103-1108, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34312798

RESUMO

BACKGROUND: Hepatitis B virus (HBV) infection is a significant global health problem and > 42-52% of patients are infected during perinatal period. Tenofovir alafenamide fumarate (TAF) and tenofovir disoproxil fumarate (TDF) have been widely recognized as the main compounds used for antiviral treatment of hepatitis B. The present study evaluated the efficacy and safety of TAF in reducing HBV vertical transmission. METHODS: A total of 72 pregnant women, who met the inclusion criteria, were randomly divided into the TDF (300 mg/day, n = 36) and TAF (25 mg/day, n = 36) groups. Clinical and laboratory data were analyzed and compared between the two groups. RESULTS: No significant differences in alanine aminotransferase, total bilirubin, blood creatinine and blood urea nitrogen levels were noted between the two groups after treatment. The serum HBV DNA viral load and hepatitis B e antigen (HBeAg) levels of the two groups were significantly decreased following treatment, whereas the difference between the two groups was not statistically significant. The levels of urine retinol-binding protein and ß2-microglobulin had no significant change after TAF treatment (p > 0.05), but increased significantly after TDF treatment (p < 0.05). All drug concentrations were undetectable in umbilical cord blood (UCB) and breast milk samples of the TAF group, while the drug concentration of UCB and breast milk samples in the TDF group was 2.98 ± 1.44 and 19.16 ± 15.26 ng/ml, respectively. All infants were tested negative for serum hepatitis B surface antigen, HBV DNA, and HBeAg. CONCLUSIONS: Both TAF and TDF effectively block the mother-to-child transmission of hepatitis B. TAF was superior to TDF with regard to renal safety and breastfeeding.


Assuntos
Vírus da Hepatite B , Hepatite B Crônica , Alanina , Antivirais/uso terapêutico , Feminino , Fumaratos/uso terapêutico , Hepatite B Crônica/tratamento farmacológico , Humanos , Lactente , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Gravidez , Tenofovir/análogos & derivados , Tenofovir/uso terapêutico , Resultado do Tratamento , Carga Viral
12.
Artigo em Inglês | MEDLINE | ID: mdl-30077093

RESUMO

Ondansetron, a potent and highly sensitive 5-hydroxytryptamine type 3 (5-HT3) receptor antagonist, has been used for the treatment of chemotherapy- and radiotherapy-induced nausea and vomiting. The isolation and identification of ondansetron metabolites were investigated in our research. The feces and bile samples collected after oral administration of ondansetron were extracted and then isolated by semi-preparative HPLC. Then the pretreated samples were characterized by LC/MSn and NMR. In rats feces, a total of four metabolites were isolated and elucidated including 7-hydroxyl-ondansetron (M1), 8-hydroxyl-ondansetron (M2), 7-hydroxyl-N-desmethyl-ondansetron (M3), and 8-hydroxyl-N-desmethyl-ondansetron (M4). In addition, a kind of metabolite of phase II isolated in rats bile was characterized as N-desmethyl-ondansetron-7-O-ß-D-glucuronide (M5). To our knowledge, three metabolites were reported for the first time. LC/MSn and NMR-based approach was proved to be useful for full structure elucidation of unknown metabolites. The systematic metabolites isolation and elucidation provided metabolite reference standards for metabolites detection of ondansetron.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Espectroscopia de Ressonância Magnética/métodos , Ondansetron , Espectrometria de Massas em Tandem/métodos , Animais , Fezes/química , Masculino , Modelos Moleculares , Ondansetron/análise , Ondansetron/química , Ondansetron/metabolismo , Ratos , Ratos Wistar
13.
Toxicon ; 46(5): 500-6, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16135377

RESUMO

To study the safety of Aconitum medicinal herbs in clinic and identify Aconitum alkaloids poisoning in forensic medicine, Aconitum alkaloids and their metabolites were separated and identified in human urine by liquid chromatography-electrospray ionization-multi-stage mass spectrometry (LC-ESI-MS(n)) and chemical pathway of metabolism was investigated. The alkaloids and their metabolites in the urine sample were extracted with solid-phase cartridges and separated by HPLC with acetonitrile-water-formic acid (40:60:0.5) mobile phase. Structures of five metabolites and three parent Aconitum alkaloids were identified with multi-stage mass spectrometry data through comparison with authentic substances as aconitine (M(1)), mesaconitine (M(2)), hypaconitine (M(3)), benzoylaconine (M(4)), benzoylmesaconine (M(5)), benzoylhypaconine (M(6)), 16-O-demethylaconitine (M(7)) and 16-O-demethylhypaconitine (M(8)), respectively. Among them, M(8) was identified and reported for the first time. Metabolic pathways of Aconitum alkaloids in human body were proposed.


Assuntos
Aconitum/química , Alcaloides/isolamento & purificação , Alcaloides/urina , Biotransformação , Cromatografia Líquida de Alta Pressão , Medicamentos de Ervas Chinesas/metabolismo , Feminino , Humanos , Espectrometria de Massas por Ionização por Electrospray
14.
Yao Xue Xue Bao ; 37(10): 781-3, 2002 Oct.
Artigo em Zh | MEDLINE | ID: mdl-12567861

RESUMO

AIM: To identify the main metabolites of aconitine in the urine of rabbits. METHODS: After oral administration of aconitine (5 mg.kg-1), the urine of male rabbits was collected and extracted by solid phase extraction and analyzed by liquid chromatography-ion trap mass spectrometry. RESULTS: Aconitine and 4 metabolites were found in the rabbit urine. Their protonated molecular ions at m/z 632, m/z 604, m/z 590, m/z 500 and multistage fragment ions with neutral loss of 60 u, 32 u, 28 u and 18 u were monitored. Their relative concentration were M1 > Aconitine > M4 > M2 > M3. CONCLUSION: The metabolites M1-M4 were deduced as 16-O-demethylaconitine, benzoylaconine, 16-O-demethylbenzoylaconine and aconine, respectively.


Assuntos
Aconitina/análogos & derivados , Aconitina/urina , Aconitina/metabolismo , Alcaloides/urina , Animais , Cromatografia Líquida de Alta Pressão , Masculino , Coelhos , Espectrometria de Massas por Ionização por Electrospray
15.
Magn Reson Chem ; 44(10): 972-5, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16835896

RESUMO

Assignments of 1H and 13C NMR chemical shifts were made by means of heteronuclear single quantum coherence (HSQC) and heteronuclear multiple bond correlation (HMBC) experiments for ondansetron, and by means of 1H-1H correlation spectroscopy (1H-1H COSY) and two-dimensional nuclear Overhauser effect spectroscopy (NOESY) experiments for two novel metabolites (M1 and M2) of ondansetron. These two metabolites were isolated for the first time from Mucor circinelloides.


Assuntos
Espectroscopia de Ressonância Magnética , Ondansetron/análogos & derivados , Ondansetron/química , Isótopos de Carbono/análise , Hidrogênio/análise , Estrutura Molecular , Mucor/metabolismo , Ondansetron/isolamento & purificação , Ondansetron/metabolismo , Estereoisomerismo
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