Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 98
Filtrar
1.
Nanoscale Res Lett ; 17(1): 8, 2022 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-34989892

RESUMO

The outstanding optoelectrical properties and high-quality factor of whispering gallery mode perovskite nanocavities make it attractive for applications in small lasers. However, efforts to make lasers with better performance have been hampered by the lack of efficient methods for the synthesis and transfer of perovskite nanocavities on desired substrate at quality required for applications. Here, we report transfer printing of perovskite nanocavities grown by chemical vapor deposition from mica substrate onto SiO2 substrate. Transferred perovskite nanocavity has an RMS roughness of ~ 1.2 nm and no thermal degradation in thermal release process. We further use femtosecond laser to excite a transferred perovskite nanocavity and measures its quality factor as high as 2580 and a lasing threshold of 27.89 µJ/cm2 which is almost unchanged as compared with pristine perovskite nanocavities. This method represents a significant step toward the realization of perovskite nanolasers with smaller sizes and better heat management as well as application in optoelectronic devices.

2.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 29(6): 1741-1745, 2021 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-34893103

RESUMO

OBJECTIVE: To investigate the clinical characteristics and prognosis of acute myeloid leukemia(AML) patients with ASXL1 mutation. METHODS: The clinical data of 229 newly diagnosed AML patients treated in our hospital from April 2016 to October 2019 were analyzed retrospectively. The next-generation sequencing technology was used to detect gene mutations in all the patients, the clinical characteristics of the patients with ASXL1 mutation were analyzed. RESULTS: ASXL1 gene mutation was detected out in 45 patients(19.6%). Among these patients, the frameshift mutation (n=22,48.9%) was most common, followed by missense mutation (n=15, 33.3%) and nonsense mutation (n=8,17.8%), respectively, all of them were located at exon 12. The median mutation rate was 32.47%(range, 2.74%-53.50%). The median age of the patients with ASXL1 mutation was 54(range, 14-74) years old, and most of the patients were male, and most of them with the history of MDS or MPN, and low white blood cell count at the initial diagnosed (P<0.05). Patients with ASXL1 mutation showed a lower CR rate than that of without ASXL1 mutation. Patients with or without ASXL1 mutation showed a statistically significant difference in survival at 20 months (P=0.042), while there was no significant difference between the patients in the two groups over 20 months (P=0.505). All the 6 patients with ASXL1 mutation in low-risk group were survived, while the median OS time was 16 months in the high-risk group(P=0.034). Multivariate analysis showed that the history of MDS or MPN and CR rate from induction therapy were the independent risk factors affecting survival of the patients. CONCLUSION: Frameshift mutation is commonly in AML patients with ASXL1 gene mutation, and ASXL1 mutation were more often in men, the history of MDS or MPN, and low white blood cell count. The CR rate of the patients with ASXL1 mutation was lower than that of the AML patients without ASXL1 mutations, AML patients with ASXL1 mutation showed poor short-term efficacy, but there was no significant difference between the two groups in long-term survival over 20 months.

3.
Signal Transduct Target Ther ; 6(1): 405, 2021 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-34795208

RESUMO

Thalidomide induces γ-globin expression in erythroid progenitor cells, but its efficacy on patients with transfusion-dependent ß-thalassemia (TDT) remains unclear. In this phase 2, multi-center, randomized, double-blind clinical trial, we aimed to determine the safety and efficacy of thalidomide in TDT patients. A hundred patients of 14 years or older were randomly assigned to receive placebo or thalidomide for 12 weeks, followed by an extension phase of at least 36 weeks. The primary endpoint was the change of hemoglobin (Hb) level in the patients. The secondary endpoints included the red blood cell (RBC) units transfused and adverse effects. In the placebo-controlled period, Hb concentrations in patients treated with thalidomide achieved a median elevation of 14.0 (range, 2.5 to 37.5) g/L, whereas Hb in patients treated with placebo did not significantly change. Within the 12 weeks, the mean RBC transfusion volume for patients treated with thalidomide and placebo was 5.4 ± 5.0 U and 10.3 ± 6.4 U, respectively (P < 0.001). Adverse events of drowsiness, dizziness, fatigue, pyrexia, sore throat, and rash were more common with thalidomide than placebo. In the extension phase, treatment with thalidomide for 24 weeks resulted in a sustainable increase in Hb concentrations which reached 104.9 ± 19.0 g/L, without blood transfusion. Significant increase in Hb concentration and reduction in RBC transfusions were associated with non ß0/ß0 and HBS1L-MYB (rs9399137 C/T, C/C; rs4895441 A/G, G/G) genotypes. These results demonstrated that thalidomide is effective in patients with TDT.

4.
Food Chem ; 360: 129977, 2021 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-34023712

RESUMO

Organic acids, as an important component of food, have great influence on the flavor, texture, freshness of food. By lowering the pH of food to bacteriostatic acidity, organic acids are also used as additives and preservatives. Because organic acids are crucial to predict and evaluate food maturity, production and quality control, the rapid and sensitive determination methods of organic acids are necessary. This review aims to summarize and update the progress of the determination of organic acids in food samples. Pretreatment methods include simple steps (e.g., "dilute and shoot," protein precipitation, filtration, and centrifugation) and advanced microextraction methods (e.g., hollow fiber liquid phase microextraction, stir bar sorptive extraction and dispersive micro-solid phase extraction). Advances in novel materials (nanomaterial), solvents (ionic liquids and supercritical fluids) and hybrid methods are clearly displayed in detail. Continuous progress which has been made in electrochemical method, two-dimensional chromatography, high resolution mass is thoroughly illustrated.


Assuntos
Ácidos/análise , Análise de Alimentos/métodos , Ácidos/química , Ácidos/isolamento & purificação , Solventes/química
5.
J Chromatogr A ; 1644: 462068, 2021 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-33836299

RESUMO

Benzimidazoles, commonly used as pesticides and veterinary drugs, have posed a threat to human health and the environment due to unreasonable use and lack of valid regulation. Therefore, an up-to-date and comprehensive summary of the pretreatment and analytical approaches in different substrates is urgently needed. The present review consequently updates and covers various newly developed pretreatment methods (e.g., cationic micellar precipitation, magnetic-solid phase extraction, hollow fiber liquid phase microextraction, disperse liquid-liquid microextraction-solidified floating organic drop, stir cake sorptive extraction, solid phase microextraction method, QuEChERS, and molecular imprinted polymer-based methods) since 2005. The review also elaborates and discusses different determination methods (e.g., newly developed HPLC and related methods, improved spectrofluorimetry methods, capillary electrophoresis, and the electrochemical sensor). Furthermore, some critical points and prospects are highlighted, to describe the trends in this area.


Assuntos
Métodos Analíticos de Preparação de Amostras , Benzimidazóis/análise , Benzimidazóis/química , Humanos , Líquidos Iônicos/química , Microextração em Fase Líquida , Extração em Fase Sólida , Microextração em Fase Sólida
6.
Med Oncol ; 38(5): 49, 2021 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-33772655

RESUMO

Increasing evidence demonstrated that alternative splicing (AS) plays a vital role in tumorigenesis and clinical outcome of patient. However, systematical analysis of AS in lung squamous cell carcinoma (LUSC) is lacking and greatly necessary. Thus, this study was to systematically estimate the function of AS events served as prognostic indicators in LUSC. Among 31,345 mRNA AS events in 9633 genes, we detected 1996 AS in 1409 genes which have significant connection with overall survival (OS) of LUSC patients. Then, prognostic model based on seven types of AS events was established and we further constructed a combined prognostic model. The Kaplan-Meier curve results suggested that seven types of AS signatures and the combined prognostic model could exhibit robust performance in predicting prognosis. Patients in the high-risk group had significantly shorter OS than those in the low-risk group. The ROC showed all prognostic models had high accuracy and powerful predictive performance with different AUC ranging from 0.837 to 0.978. Moreover, the combined prognostic model had highest performance in risk stratification and predictive accuracy than single prognostic models and had higher accuracy than other mRNA model. Finally, a significant correlation network between survival-related AS genes and prognostic splicing factors (SFs) was established. In conclusion, our study provided several potential prognostic AS models and constructed splicing network between AS and SFs in LUSC, which could be used as potential indicators and treatment targets for LUSC patients.


Assuntos
Processamento Alternativo/genética , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/mortalidade , Bases de Dados Genéticas/tendências , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/mortalidade , Carcinoma de Células Escamosas/diagnóstico , Estudos de Coortes , Humanos , Neoplasias Pulmonares/diagnóstico , Taxa de Sobrevida/tendências
7.
J Phys Chem Lett ; 12(9): 2232-2244, 2021 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-33635675

RESUMO

Profound understanding of the luminescence mechanism and structure-property relationship is vital for Cu(I) thermally activated delayed fluorescence (TADF) emitters. Herein, we theoretically simulated luminescent behavior in both solution and solid phases for two Cu(I) complexes and found the following: (i) The strengthened spin-orbit coupling (SOC) effect by more dx2-y2 orbital contributions and well-restricted structural distortion via remarkable intramolecular interaction in [Cu(dmp)(POP)]+ enable the emission at room temperature to be a mixture of direct phosphorescence (10%) and TADF (90%). (ii) Benefiting from enhanced steric hindrance and the electron-donating ability of the paracyclophane group, the narrowed S1-T1 energy separation (ΔEST) in [Cu(dmp)(phanephos)]+ accelerates the reverse intersystem crossing, promoting the TADF rate (1.88 × 105 s-1) and intensity ratio (98.3%). These results indicate that the small ΔEST is superior for reducing the lifetime and that the strong SOC stimulates the phosphorescence to compete with TADF, which are both conducive to avoiding collision-induced exciton quenching and reducing the roll-off in devices.

8.
J Ethnopharmacol ; 273: 113950, 2021 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-33610713

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Thesium chinense Turcz. has been used to treat mastitis, pulmonitis, tonsillitis, iaryngopharyngitis and upper respiratory tract infections in the indigenous medicine of China for a long history. Presently, several pharmaceutics prepared by this medical herb have been clinically used for the therapy of infectious diseases. AIM OF THE REVIEW: This review aims to comprehensively summarize the current researches on the ethnomedical, phytochemical and pharmacological aspects of T. chinense, and discuss their possible opportunities for the future research. MATERIALS AND METHODS: Extensive database searches, including Web of Science, SciFinder, Google Scholar and China Knowledge Resource Integrated, were performed using keywords such as 'Thesium chinense', 'Bai Rui Cao', and their chemical constituents. In addition, local classic herbal literature on ethnopharmacology and relevant textbooks were consulted to provide a comprehensive survey of this ethnomedicine. RESULTS: Thirty four chemical constituents, including flavonoids, alkaloids, and terpenoids, have been identified from T. chinense. Of which, flavonoids are the predominant and characteristic constituents. The crude extracts, the purified constituents, and commercial available pharmaceutics have displayed diverse in vitro and in vivo pharmacological functions (e.g. anti-inflammation, antimicrobial activity, analgesic effect, hepaprotection), and are particularly useful as a potential therapeutic agent against inflammation-related diseases. CONCLUSIONS: T. chinense is an important ethnomedical medicine and possesses a satisfying effect for treating inflammation, microbial infection, and upper respiratory diseases. It has received plenty of researches on its phytochemical and pharmacological aspects since 1970s. These findings definitely establish the link between chemical composition and pharmacological application, and support the ethnomedical use of T. chinense in the indigenous medicine of China. However, chemical composition of this plant and the molecular mechanisms of purified constituents have not been comprehensively investigated, and thus the trace constituents and the therapeutic targets of bioactive constituents deserve a further exploration. Collectively, the researchers should pay more attention to a better understanding and application of this ethnomedical plant.


Assuntos
Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/farmacologia , Compostos Fitoquímicos/química , Compostos Fitoquímicos/farmacologia , Santalaceae/química , Animais , Estudos Clínicos como Assunto , Medicamentos de Ervas Chinesas/uso terapêutico , Medicamentos de Ervas Chinesas/toxicidade , Humanos , Medicina Tradicional Chinesa , Compostos Fitoquímicos/uso terapêutico , Compostos Fitoquímicos/toxicidade
9.
Ann Palliat Med ; 10(1): 285-291, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33353353

RESUMO

BACKGROUND: To investigate the reference value of blood gas analysis and related factors in healthy adults in Diqing Tibetan Autonomous Prefecture in Yunnan Province. METHODS: From August 24, 2018 to August 11, 2020, healthy people between the ages of 18 and 70 years were observed at the Physical Examination Center of People's Hospital of Diqing Tibetan Autonomous Prefecture in Yunnan province. Participant information and clinical characteristics were collected. Blood gas analyzer was used to measure PH value, arterial partial oxygen pressure (PaO2), arterial partial pressure of carbon dioxide (PaCO2), arterial oxygen saturation (SaO2), acidity (pH), actual bicarbonate (AB) and residual base (BE). The participants' basic and blood gas indicator data were analyzed, and the blood gas reference values and related factors were analyzed using chi-squared tests, Mann-Whitney-Wilcoxon Test, and Spearman's correlation analysis. RESULTS: A total of 1,218 eligible health examination participants were included. They had an average age of 40 [31-47] years, and males accounted for 51.0%. In terms of blood gas reference values, the average pH value was moderate, and the values of PaO2, SaO2, PaCO2, AB, and BE were low. PaO2 was basically matched with the estimated value of the domestic model formula. These indexes were found to be correlated with social demographic characteristics such as sex, age, and smoking history. CONCLUSIONS: The correlations between the indexes and social demographic characteristics may be helpful in the prediction of blood gas analysis results in clinical practice. For men, middle-aged and elderly people, or adults with a history of active smoking/biofuel exposure, blood gas PaO2 and PaCO2 should be monitored to facilitate the early intervention of respiratory failure. The PaO2 data basically matched the estimated values of the domestic model formula, suggesting that other regions in the Prefecture could use comprehensive epidemiological data and model methods to guide clinical work.


Assuntos
Oxigênio , Adolescente , Adulto , Idoso , Gasometria , China , Humanos , Masculino , Pessoa de Meia-Idade , Pressão Parcial , Tibet , Adulto Jovem
10.
Lung Cancer ; 152: 39-48, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33341538

RESUMO

OBJECTIVES: Epidermal growth factor receptor (EGFR) exon 20 insertion (ex20 ins) mutations are generally associated with de novo resistance to first- or second-generation EGFR tyrosine kinase inhibitors in non-small cell lung cancer (NSCLC). However, the real efficacy of osimertinib for this subset remains elusive. We performed this study to investigate the real efficacy of osimertinib for Chinese advanced NSCLC patients harboring EGFR ex20 ins mutations. MATERIALS AND METHODS: We retrospectively collected data of metastatic NSCLC patients with EGFR ex20 ins mutations who were treated with osimertinib 80 mg or 160 mg once daily in our center from June 2017 to May 2020. Progression-free survival (PFS), objective response rate (ORR) and disease control rate (DCR) were assessed. RESULTS: A total of 62 cases with EGFR ex20 ins mutations were included, and the major insertion variant was D770_N771insSVD and V769_D770insASV (45.1 %). Concurrent TP53 mutation was most commonly observed (59.7 %). Four patients showed partial response, 29 cases with stable disease and 29 showed progressive disease as best response to osimertinib (ORR: 6.5 %, DCR: 53.2 %). The median PFS (mPFS) in total patients was 2.3 (95 %CI, 1.5-3.1) months. Patients harboring A763_Y764insFQEA/D770delinsGY variants showed numerically longer mPFS than those with other variants (4.2 vs. 2.2 months, P =  0.164). Patients who failed to osimertinib and occurred extracranial progression showed similar mPFS to those with intracranial progression (2.3 vs. 1.9 months, P =  0.142). Median PFS was not significantly different between patients who received osimertinib 80mg or 160mg once daily (2.5 vs. 1.3 months, P = 0.161), either with no significance when it used in fist-line setteing or bove (3.0 vs. 2.2 months, P =  0.639). CONCLUSION: The unique insertion variant A763_Y764insFQEA and D770delinsGY might better respond to osimertinib than other ex20 ins subtypes. Osimertinib either 80 mg or 160 mg once daily showed less activity in Chinese NSCLC patients harboring diverse EGFR ex20 ins mutations.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Acrilamidas , Compostos de Anilina , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , China , Receptores ErbB/genética , Éxons/genética , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Mutagênese Insercional , Mutação , Inibidores de Proteínas Quinases/uso terapêutico , Estudos Retrospectivos
11.
Crit Rev Anal Chem ; 51(1): 55-86, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-31646873

RESUMO

Cephalosporins, one of the classic ß-lactam antibiotics, has been widely concerned by global population as the most commonly used broad-spectrum antibiotic. Serious health hazards are possible to be posed by quality control problems caused by its unstable structure, as well as food and environmental pollution introduced by improper use. Given the reasons above, the sensitive and valid methods for monitor and determination of cephalosporins in different matrices are urgently required. This review aims to provide a comprehensive overview on the current status of the pretreatment and analysis methods of cephalosporins in bulk drug, pharmaceutics, animal-derived foodstuffs including eggs, milk, meat, environment samples, and biological samples. Pretreatment methods including simple steps (protein precipitation, centrifugation, filtration), liquid-liquid extraction, solid phase extraction, QuECHERS, and detection methods covering LC, LC-MS/MS, voltammetric sensor, capillary electrophoresis spectroscopy, biological methods from January 2005 to October 2018 are updated, elaborated and compared here. Moreover, advanced materials and prospects for development are discussed. HighlightsDetermination of cephalosporins in different newly found matrix are represented.Comparisons between different mass analyzers and progress in HRMS methods are in detailed.Optimization of experimental conditions are discussed.Newly emerged eco-friendly methods are introduced.


Assuntos
Antibacterianos/análise , Cefalosporinas/análise , Poluentes Ambientais/análise , Contaminação de Alimentos/análise , Cromatografia Líquida/métodos , Extração em Fase Sólida/métodos , Espectrometria de Massas em Tandem/métodos
12.
Crit Rev Food Sci Nutr ; 61(21): 3626-3660, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32776791

RESUMO

As highly toxic substances, N-nitrosamines (NAs) have been proved to cause carcinogenesis and mutagenesis in humans. Therefore, to carefully monitor safety and preserve human health, the development of rapid, accurate, and high-sensitivity determination methods of NAs is of substantial importance. This review provides a current-status comprehensive summary of the pretreatment and determination methods of NAs in various samples since 2010. Common pretreatment methods that have been used to extract and purify targets include solid-phase extraction, liquid-liquid extraction and various microextraction methods, such as solid-phase microextraction and liquid-phase microextraction, among others. Determination methods include liquid chromatography, gas chromatography, supercritical fluid chromatography and electrochemical methods, among others. In addition, we discuss and compare the advantages and disadvantages of various pretreatment and analytical methods and examine the prospects in this area.

13.
Crit Rev Anal Chem ; : 1-34, 2020 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-32880479

RESUMO

Food safety and quality issues are becoming increasingly important and attract much attention, requiring the development of better analytical platforms. For example, high-resolution (especially Orbitrap) mass spectrometry simultaneously offers versatile functions such as targeted/non-targeted screening while providing qualitative and quantitative information on an almost unlimited number of analytes to facilitate routine analysis and even allows for official surveillance in the food field. This review covers the current state of Orbitrap mass spectrometry (OMS) usage in food analysis based on research reported in 2012-2019, particularly highlighting the technical aspects of OMS application and the achievement of OMS-based screening and quantitative analysis in the food field. The gained insights enhance our understanding of state-of-the-art high-resolution mass spectrometry and highlight the challenges and directions of future research.

14.
Front Pharmacol ; 11: 810, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32547402

RESUMO

Although increasing reports from the literature on herbal-related hepatotoxicity, the identification of susceptibility-related factors and biomarkers remains challenging due to idiosyncratic drug-induced liver injury (IDILI). As a well-known Chinese medicine prescription, Xianling Gubao Capsule (XLGB) has attracted great attention due to reports of potential liver toxicity. But the mechanism behind it is difficult to determine. In this paper, we found that XLGB-induced liver injury belongs to IDILI through the analysis of clinical liver injury cases. In toxicological experiment assessment, co-exposure to XLGB and non-toxic dose of lipopolysaccharide (LPS) could cause evident liver injury as manifested by significantly increased plasma alanine aminotransferase activity and obvious liver histological damage. However, it failed to induce observable liver injury in normal rats, suggesting that mild immune stress may be a susceptibility factor for XLGB-induced idiosyncratic liver injury. Furthermore, plasma cytokines were determined and 15 cytokines (such as IL-1ß, IFN-γ, and MIP-2α etc) were acquired by receiver operating characteristic (ROC) curves analysis. The expression of these 15 cytokines in LPS group was significantly up-regulated in contrast to the normal group. Meanwhile, the metabolomics profile showed that mild immune stress caused metabolic reprogramming, including sphingolipid metabolism, phenylalanine metabolism, and glycerophospholipid metabolism. 8 potential biomarkers (such as sphinganine, glycerophosphoethanolamine, and phenylalanine etc.) were identified by correlation analysis. Therefore, these results suggested that intracellular metabolism and immune changes induced by mild immune stress may be important susceptibility mechanisms for XLGB IDILI.

15.
Pharmacogenomics J ; 20(2): 169-178, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31796890

RESUMO

Many medical centers in the United States have implemented pharmacogenomics (PGx) programs to integrate PGx into clinical practice. The roles of pharmacists in optimizing medication use based on genetic testing results are emergently evolving. A literature search was conducted to assess pharmacists' roles in pharmacogenetics/pharmacogenomics or precision/personalized medicine programs. Fifteen PGx pharmacy practice models implemented in eleven hospitals and one community pharmacy in the U.S. were selected for evaluation. Pharmacists perform results interpretation, genotype-guided medication selection and adjustment, medication acquisition, adverse reactions monitoring, and patient education. Institutions that are interested in implementing a PGx program should plan the strategies to overcome the challenges, such as educational knowledge gaps, informatics, and reimbursement issues. Strong institutional support, well-defined goals, standardized procedures, and strategies to educate clinicians and patients are the prerequisites to comprehensively deliver genomic data for individualized drug therapy.


Assuntos
Serviços Comunitários de Farmácia/organização & administração , Conduta do Tratamento Medicamentoso/organização & administração , Farmacêuticos/organização & administração , Farmacogenética/métodos , Medicina de Precisão/métodos , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Educação de Pacientes como Assunto , Papel Profissional , Estados Unidos
16.
Biomed Pharmacother ; 121: 109669, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31766100

RESUMO

Oxidative stress is closely associated to the onset and progression of many human diseases. Activation of the nuclear factor erythroid 2-related factor 2 (Nrf2)/antioxidant response element (ARE) signaling pathway using naturally-derived molecules is an efficient strategy for alleviating the intracellular oxidative insults, and thus blocking the pathogenesis of oxidative stress-induced diseases. In the present study, a naturally-derived isopimarane-type diterpenoid sphaeropsidin C (SC) was identified to be an activator of Nrf2/ARE signaling pathway. Our data indicated that SC was able to stimulate Nrf2-mediated defensive system through promoting Nrf2 translocation, inhibiting Nrf2 ubiquitination, and enhancing Nrf2 stability in normal human lung epithelial Beas-2B cells. Furthermore, SC-induced Nrf2 activation required the involvement of protein kinases, exemplified by protein kinase C (PKC), protein kinase R-like endoplasmic reticulum kinase (PERK), and phosphatidylinositol-4,5-bisphosphate 3-kinase (PI3K). It alleviated sodium arsenite [As(III)]-induced intracellular oxidative stress in an Nrf2-dependent manner. These results suggested that SC displayed potential application for the prevention and therapy against oxidative stress-induced diseases. Moreover, isopimarane-type diterpenoid represents a promising skeleton for developing Nrf2 activators.


Assuntos
Hidrolases de Éster Carboxílico/metabolismo , Diterpenos/farmacologia , Células Epiteliais/efeitos dos fármacos , Pulmão/efeitos dos fármacos , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Animais , Antioxidantes/metabolismo , Arsenitos/farmacologia , Linhagem Celular Tumoral , Células Epiteliais/metabolismo , Humanos , Pulmão/metabolismo , Camundongos , Fosfatidilinositol 3-Quinases/metabolismo , Proteína Quinase C/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Compostos de Sódio/farmacologia
17.
Crit Rev Anal Chem ; 50(2): 136-160, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-30900462

RESUMO

Recently, supercritical fluid chromatography (SFC) has attracted considerable attention for their application in food analysis. The use of supercritical CO2 (SC-CO2), as a mobile phase for SFC, with its low viscosity and high molecular diffusiveness, results in shorter analysis time and lower consumption of organic solvents as compared to high-performance liquid chromatography (HPLC). In addition, with recent improvements in its detection system, SFC has shown satisfactory selectivity and sensitivity. Thus, although the composition of food is complex, SFC remains a powerful tool in food analysis with some simple sample pretreatment techniques, such as liquid-liquid extraction, solid-phase extraction, and QuEChERS. Here, we summarize the applications of SFC in food quality and safety from 2012 to 2018, and mainly focus on sample pretreatment strategies and analysis conditions.


Assuntos
Cromatografia com Fluido Supercrítico , Análise de Alimentos , Qualidade dos Alimentos , Inocuidade dos Alimentos
18.
Free Radic Biol Med ; 152: 525-539, 2020 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-31760092

RESUMO

Chronic obstructive pulmonary disease (COPD) is a chronic inflammatory disease resulted from airflow obstructions, and there is a driving requirement for novel and effective preventive and therapeutic agents of COPD. Nuclear factor-erythroid 2-related factor 2 (Nrf2) has been regarded to be a promising therapeutic target for COPD. Resveratrol is a natural Nrf2 activator with antioxidant and anti-inflammatory properties, however, its application is limited by its relative low efficiency and poor bioavailability. Herein, based on the skeleton of resveratrol, trans-4,4'-dihydroxystilbene (DHS) has been firstly identified to be an Nrf2 activator, which is more potent than the well-known sulforaphane (SF) and resveratrol. Our results indicate that DHS blocks Nrf2 ubiquitylation through specifically reacting with Cys151 cysteine in Keap1 protein to activate Nrf2-regulated defensive response, and thus enhances intracellular antioxidant capability. Furthermore, DHS relieves lipopolysaccharide (LPS)-stimulated inflammatory response via inhibition of NF-κB. Importantly, DHS significantly ameliorates pathological alterations (e.g. infiltration of leukocytes and fibrosis), downregulates the levels of oxidant biomarkers malondialdehyde (MDA) and 8-oxo-7,8-dihydro-2'-deoxyguanosin (8-oxo-dG), and inhibits the overproductions of inflammatory mediators [e.g. tumor necrosis factor α (TNF-α), cyclooxygenase-2 (COX-2), and matrix metalloproteinase-9 (MMP-9)] in a cigarette smoke (CS)-induced pulmonary impairment mice model. Taken together, this study demonstrates that DHS attenuates the CS-induced pulmonary impairments through inhibitions of oxidative stress and inflammatory response targeting Nrf2 and NF-κB in vitro and in vivo, and could be developed into a preventive agent against pulmonary impairments induced by CS.


Assuntos
Fator 2 Relacionado a NF-E2 , Doença Pulmonar Obstrutiva Crônica , Animais , Proteína 1 Associada a ECH Semelhante a Kelch/genética , Pulmão/metabolismo , Camundongos , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Fumar/efeitos adversos , Estilbenos
19.
Analyst ; 144(18): 5324-5352, 2019 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-31348475

RESUMO

Medicinal plants with complex matrices are endowed with a wide scope of biological activities. The separation, quantification, characterization and purification of bioactive components from herbal medicine extracts have always challenged analysts. Fortunately, the advancement of various emerging techniques has provided potent support for improving the method selectivity, sensitivity and run speeds in medicinal plant analyses. In recent years, the advent of new-generation supercritical fluid chromatography (SFC) instruments and a wide diversity of column chemistries, coupled with the intrinsic technical features of SFC, have made it an alternative and prominent analytical platform in the medicinal plant research area. This work aims to give a comprehensive overview of the fundamentals, technical advancement and investigating parameters of SFC in combination with three prevalent detectors. Moreover, the latest research progress of SFC applications in medicinal plant analyses is illuminated, with focus on herbal medicine-related SFC papers on the analytical and preparative scale that were published during the period of 2012 to December 2018. The most relevant applications were classified based on the constituents to be analysed. As for the respective research cases, analytical protocols and data processing strategies were provided, along with the indicated restrictions or superiority of the method; thus, the current status of SFC in medicinal plant analysis was presented.


Assuntos
Cromatografia com Fluido Supercrítico/métodos , Compostos Fitoquímicos/análise , Plantas Medicinais/química , Cromatografia com Fluido Supercrítico/instrumentação
20.
J Chromatogr A ; 1605: 360361, 2019 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-31327479

RESUMO

Biogenic amines (BAs), mainly produced by amino acid decarboxylation, are widespread in foods and human organisms. Appropriate intake of BAs is beneficial to the human body, while excessive consumption may cause discomfort. Meanwhile, BAs are a kind of chemical marker for evaluating meat freshness. For these reasons, simple, rapid and efficient methods have been developed for the determination of BAs in food and biological products. This review introduces the provenance, classification and physiological activity of eight essential BAs and summarizes the dominant pretreatment and analysis methods since 2010. Pretreatment technologies mainly include the "dilute and shoot" method, ultrasonic assisted extraction, solid-phase extraction, matrix solid-phase dispersion, dispersive liquid-liquid microextraction, etc. Determination methods include liquid chromatography coupled to ultraviolet or fluorescence detectors, liquid chromatography tandem mass spectrometry, capillary electrophoresis, biosensors and so on.


Assuntos
Métodos Analíticos de Preparação de Amostras , Aminas Biogênicas/análise , Análise de Alimentos/métodos , Aminoácidos/análise , Animais , Aminas Biogênicas/química , Técnicas Biossensoriais , Humanos , Carne/análise
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...