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1.
Acta Pharmacol Sin ; 45(7): 1438-1450, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38565961

RESUMO

Angiogenesis plays a critical role in many pathological processes, including irreversible blindness in eye diseases such as retinopathy of prematurity. Endothelial mitochondria are dynamic organelles that undergo constant fusion and fission and are critical signalling hubs that modulate angiogenesis by coordinating reactive oxygen species (ROS) production and calcium signalling and metabolism. In this study, we investigated the role of mitochondrial dynamics in pathological retinal angiogenesis. We showed that treatment with vascular endothelial growth factor (VEGF; 20 ng/ml) induced mitochondrial fission in HUVECs by promoting the phosphorylation of dynamin-related protein 1 (DRP1). DRP1 knockdown or pretreatment with the DRP1 inhibitor Mdivi-1 (5 µM) blocked VEGF-induced cell migration, proliferation, and tube formation in HUVECs. We demonstrated that VEGF treatment increased mitochondrial ROS production in HUVECs, which was necessary for HIF-1α-dependent glycolysis, as well as proliferation, migration, and tube formation, and the inhibition of mitochondrial fission prevented VEGF-induced mitochondrial ROS production. In an oxygen-induced retinopathy (OIR) mouse model, we found that active DRP1 was highly expressed in endothelial cells in neovascular tufts. The administration of Mdivi-1 (10 mg·kg-1·d-1, i.p.) for three days from postnatal day (P) 13 until P15 significantly alleviated pathological angiogenesis in the retina. Our results suggest that targeting mitochondrial fission may be a therapeutic strategy for proliferative retinopathies and other diseases that are dependent on pathological angiogenesis.


Assuntos
Movimento Celular , Dinaminas , Células Endoteliais da Veia Umbilical Humana , Subunidade alfa do Fator 1 Induzível por Hipóxia , Camundongos Endogâmicos C57BL , Dinâmica Mitocondrial , Quinazolinonas , Espécies Reativas de Oxigênio , Neovascularização Retiniana , Fator A de Crescimento do Endotélio Vascular , Dinâmica Mitocondrial/efeitos dos fármacos , Animais , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Humanos , Espécies Reativas de Oxigênio/metabolismo , Dinaminas/metabolismo , Dinaminas/antagonistas & inibidores , Fator A de Crescimento do Endotélio Vascular/metabolismo , Quinazolinonas/farmacologia , Neovascularização Retiniana/metabolismo , Neovascularização Retiniana/patologia , Neovascularização Retiniana/tratamento farmacológico , Movimento Celular/efeitos dos fármacos , Camundongos , Proliferação de Células/efeitos dos fármacos , Mitocôndrias/metabolismo , Mitocôndrias/efeitos dos fármacos , Angiogênese
2.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 46(3): 414-424, 2024 Jun.
Artigo em Zh | MEDLINE | ID: mdl-38953266

RESUMO

Helicobacter pylori (Hp) is a common Gram-negative bacillus causing gastrointestinal infections.It mainly exists on the surface of gastric epithelial cells and in mucus and is associated with gastric ulcers,gastric cancer,and gastric mucosa-associated lymphomas.Studies have shown that Hp can induce or exacerbate certain extragastric diseases and is associated with the occurrence of coronavirus disease 2019.It is hypothesized that Hp may be indirectly or directly involved in the occurrence and development of diseases by stimulating the production of inflammatory cytokines or inducing cross-immune reactions.In addition,Hp can enter Candida to release toxins continuously and play a role in escaping the recognition of the host immune system and the bactericidal effect of drugs.This article reviews the research progress in Hp-associated extragastric diseases in recent years,aiming to draw the attention of clinical workers to Hp-associated extragastric diseases and enrich the knowledge about Hp infection for formulating countermeasures to avoid the aggravation or triggering of other diseases by Hp.


Assuntos
Infecções por Helicobacter , Helicobacter pylori , Humanos , Infecções por Helicobacter/complicações , COVID-19
3.
Angew Chem Int Ed Engl ; 63(21): e202400769, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38544401

RESUMO

Generating circularly polarized luminescence (CPL) with simultaneous high photoluminescence quantum yield (PLQY) and dissymmetry factor (glum) is difficult due to usually unmatched electric transition dipole moment (µ) and magnetic transition dipole moment (m) of materials. Herein we tackle this issue by playing a "cascade cationic insertion" trick to achieve strong CPL (with PLQY of ~100 %) in lead-free metal halides with high glum values reaching -2.3×10-2 without using any chiral inducers. Achiral solvents of hydrochloric acid (HCl) and N, N-dimethylformamide (DMF) infiltrate the crystal lattice via asymmetric hydrogen bonding, distorting the perovskite structure to induce the "intrinsic" chirality. Surprisingly, additional insertion of Cs+ cation to substitute partial (CH3)2NH2 + transforms the chiral space group to achiral but the crystal maintains chiroptical activity. Further doping of Sb3+ stimulates strong photoluminescence as a result of self-trapped excitons (STEs) formation without disturbing the crystal framework. The chiral perovskites of indium-antimony chlorides embedded on LEDs chips demonstrate promising potential as CPL emitters. Our work presents rare cases of chiroptical activity of highly luminescent perovskites from only achiral building blocks via spontaneous resolution as a result of symmetry breaking.

4.
Anal Bioanal Chem ; 415(12): 2249-2260, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36920495

RESUMO

In this work, we design and synthesize 2,2'-(7,9-dimethyl-2,4,6,8-tetraoxo-6,7,8,9-tetrahydropyrimido[5,4-g]pteridine-1,3(2H,4H)-diyl)bis(N,N-bis(2-chloroethyl)acetamide) (PT-MCA) as a novel DNA intercalator and potential antitumor agent. Electrochemical analysis reveals the redox process of PT-MCA on the electrode surface. The bioelectrochemical sensors are obtained by modifying the surface of GCE with calf thymus DNA (ctDNA), poly (dG), poly (dA), and G-quadruplex, respectively. The DNA oxidative damage induced by PT-MCA is investigated by comparing the peak intensity change of dGuo and dAdo and monitoring the peaks of the oxidation products of guanine and/or adenine (8-oxoGua and/or 2,8-oxoAde). UV-vis absorption and fluorescence spectra and gel electrophoresis are further employed to understand the intercalation of PT-MCA into DNA base pairs. Moreover, PT-MCA is proved to exhibit stronger anti-proliferation activity than mitoxantrone against both 4T1 and B16-F10 cancer cells. At last, the oxidative damage of PT-MCA toward ctDNA is not interfered by the coexistence of ions and also can be detected in real serums.


Assuntos
Antineoplásicos , Pteridinas , DNA/genética , Antineoplásicos/farmacologia , Adenina , Estresse Oxidativo , Dano ao DNA
5.
J Environ Sci (China) ; 132: 122-133, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37336603

RESUMO

Recently, the global background concentration of ozone (O3) has demonstrated a rising trend. Among various methods, groun-based monitoring of O3 concentrations is highly reliable for research analysis. To obtain information on the spatial characteristics of O3 concentrations, it is necessary that the ground monitoring sites be constructed in sufficient density. In recent years, many researchers have used machine learning models to estimate surface O3 concentrations, which cannot fully provide the spatial and temporal information contained in a sample dataset. To solve this problem, the current study utilized a deep learning model called the Residual connection Convolutional Long Short-Term Memory network (R-ConvLSTM) to estimate daily maximum 8-hr average (MDA8) O3 over Jiangsu province, China during 2020. In this research, the R-ConvLSTM model not only provides the spatiotemporal information of MDA8 O3, but also involves residual connection to avoid the problem of gradient explosion and gradient disappearance with the deepening of network layers. We utilized the TROPOMI total O3 column retrieved from Sentinel-5 Precursor, ERA5 reanalysis meteorological data, and other supplementary data to build a pre-trained dataset. The R-ConvLSTM model achieved an overall sample-base cross-validation (CV) R2 of 0.955 with root mean square error (RMSE) of 9.372 µg/m3. Model estimation also showed a city-based CV R2 of 0.896 with RMSE of 14.029 µg/m3, the highest MDA8 O3 in spring being 122.60 ± 31.60 µg/m3 and the lowest in winter being 69.93 ± 18.48 µg/m3.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Aprendizado Profundo , Ozônio , Ozônio/análise , Poluição do Ar/análise , Poluentes Atmosféricos/análise , Monitoramento Ambiental/métodos , China
6.
Plant Dis ; 2022 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-35486601

RESUMO

In July 2019, leaf blight on Actaea dahurica, a plant with high value in Chinese traditional medicine, was discovered in a 2 ha planting area in Heilongjiang Province (129.6°E, 44.6°N), China. Disease incidence was 90% in the field. Symptoms consisted of irregular black spots with gray margins on both sides of the leaf, often at the leaf margin, mostly on the older leaves. To isolate the pathogen, ten diseased leaves were randomly collected, surface disinfested, and 5 x 5 mm segments were removed from the margin of the lesions. Leaf segments were placed onto potato dextrose agar (PDA) and incubated at 25 ℃ for 7 days. Ten pure cultures with the same morphological characteristics were obtained from three leaves showing typical symptoms. Cultures on PDA initially had a cottony mycelium, white-gray to gray. After two to three weeks of growth, mycelium color changed from gray to black. Conidiophores were clustered, dark at the base, tapering to the apex, born from simple sublates, unbranched, with 1 to 5 septa, and 70.4-530.3 × 5-7.5 µm in size. Conidia were 12.5-82.5 × 5.2-20.3 µm, usually in chains, had 2 to 8 transverse septa, 0 to 4 longitudinal or oblique septa, and a smooth brown surface. Simple, pale, vimineous or verrucous beaks developed from the apical cells with 0 to 4 septa. The morphological characteristics were consistent with Alternaria species (Simmons, 2007). To fulfill Koch's postulates, pathogenicity tests were carried out on three-month-old A. dahurica plants. A spore suspension was prepared from PDA cultures of isolates SM0101 and SM0102 and adjusted to 105 spores/mL using a hemocytometer. Each leaf was sprayed with 2 mL of the spore suspension, then incubated at 25 ℃ for 7 days. The same number of healthy A. dahurica plants were sprayed with sterile water as a control. After 7 days, small brown necrotic spots appeared on inoculated plants, but the control group showed no symptoms. A fungus with the same characteristics as that used for inoculation was re-isolated from the lesions. This experiment was replicated three times, and the results of each experiment were consistent. Genomic DNA was extracted from isolates SM0101 and SM0102 and used for PCR amplification of the rDNA internal transcribed spacer regions (ITS), RNA polymerase II gene (RPB2) and Alternaria allergen a 1 (Alt a 1) gene sequences using the primer pairs ITS1/ITS4 (White et al. 1990), RPB2-5F2/RPB2-7CR (Khodaei and Arzanlou, 2013) and Alt-for/Alt-rev (Hong et al. 2005), respectively. The ITS (OL703042, OL616086), RPB2 (OL703043, OL898416), and Alt a 1 sequences (OL616087, OL898415) were deposited in GenBank. The sequences obtained in this study had the highest match to corresponding sequences of Alternaria alternata CBS 916.96 (AF347031, KC584375, AY563301). For isolate SM0101 the matches were ITS (461/461 bp), RPB2 (897/985 bp), and Alt a 1 (488/488 bp). For isolate SM0202 the matches were ITS (457/457 bp), RPB2 (893/985 bp), and Alt a 1 (484/484 bp). A phylogenetic analysis was performed using MEGA7 software. The alignment included sequences from 16 ex-type Alternaria species and the two isolates causing leaf blight on A. dahurica. Branch supports were calculated with 1,000 bootstrap replicates, and phylogenetic inference was performed using the maximum likelihood estimation. The fungus isolated from A. dahurica clustered with A. alternata. This is the first report of A. alternata on A. dahurica in the world. This report will help to identify the disease symptoms in the field and provides a basis for research into the occurrence, distribution, and control of leaf blight on A. dahurica.

7.
Carcinogenesis ; 42(4): 587-600, 2021 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-33151304

RESUMO

c-Met hyperactivity has been observed in numerous neoplasms. Several researchers have shown that the abnormal activation of c-Met is mainly caused by transcriptional activation. However, the molecular mechanism behind this transcriptional regulation is poorly understood. Here, we suggest that Smad3 negatively regulates the expression and activation of c-Met via a transcriptional mechanism. We explore the molecular mechanisms that underlie Smad3-induced c-Met transcription inhibition. We found in contrast to the high expression of c-Met, Smad3 showed low protein and mRNA levels. Smad3 and c-Met expressions were inconsistent between lung cancer tissues and cell lines. We also found that Smad3 overexpression suppresses whereas Smad3 knockdown significantly promotes Epithelial-Mesenchymal Transition and production of the angiogenic factors VEGF, CTGF and COX-2 through the ERK1/2 pathway. In addition, Smad3 overexpression decreases whereas Smad3 knockdown significantly increases protein and mRNA levels of invasion-related ß-catenin and FAK through the PI3K/Akt pathway. Furthermore, using the chromatin immunoprecipitation analysis method, we demonstrate that a transcriptional regulatory complex consisting of HDAC1, Smad3 and mSin3A binds to the promoter of the c-Met gene. By either silencing endogenous mSin3A expression with siRNA or by pretreating cells with a specific HDAC1 inhibitor (MS-275), Smad3-induced transcriptional suppression of c-Met could be effectively attenuated. These results demonstrate that Smad3-induced inhibition of c-Met transcription depends on of a functional transcriptional regulatory complex that includes Smad3, mSin3A and HDAC1 at the c-Met promoter. Collectively, our findings reveal a new regulatory mechanism of c-Met signaling, and suggest a potential molecular target for the development of anticancer drugs.


Assuntos
Histona Desacetilase 1/genética , Neoplasias Pulmonares/genética , Complexo Correpressor Histona Desacetilase e Sin3/genética , Proteína Smad3/genética , Linhagem Celular Tumoral , Fator de Crescimento do Tecido Conjuntivo/genética , Ciclo-Oxigenase 2/genética , Transição Epitelial-Mesenquimal/genética , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Neoplasias Pulmonares/patologia , Fosfatidilinositol 3-Quinases/genética , Regiões Promotoras Genéticas/genética , Proteínas Proto-Oncogênicas c-met/genética , Ativação Transcricional/genética , Fator A de Crescimento do Endotélio Vascular/genética , beta Catenina/genética
8.
Anal Bioanal Chem ; 413(2): 585-597, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33184759

RESUMO

The toxic protein of ricin has drawn wide attention in recent years as a potential bioterrorism agent due to its high toxicity and wide availability. For the verification of the potential anti-terrorism activities, it is urgent for the quantification of ricin in food-related matrices. Here, a novel strategy of trypsin/Glu-C tandem digestion was introduced for quantitative detection of ricin marker peptides in several beverage matrices using isotope-labeled internal standard (IS)-mass spectrometry. The ricin in beverages was captured and enriched by biotinylated anti-ricin polyclonal antibodies conjugated to streptavidin magnetic beads. The purified ricin was cleaved using the developed trypsin/Glu-C tandem digestion method and then quantitatively detected by ultra-high-pressure liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) with isotope-labeled T7A and TG11B selected as IS. The use of trypsin/Glu-C digestion allows shorter peptides, which are more suitable for MS detection, to be obtained than the use of single trypsin digestion. Under the optimized tandem digestion condition, except for T7A in the A-chain, two resulting specific peptides of TG13A, TG28A from the A-chain and two of TG11B, TG33B from the B-chain were chosen as novel marker peptides with high MS response. The uniqueness of the selected marker peptides allows for unambiguous identification of ricin among its homologous proteins in a single run. The MS response of the four novel marker peptides is increased by more than 10 times compared with that of individual corresponding tryptic peptides. Both the marker peptides of A-chain T7A and B-chain TG11B were selected as quantitative peptides based on the highest MS response among the marker peptides from their individual chains. The limit of detection (LOD) of ricin is 0.1 ng/mL in PBS and 0.5 ng/mL in either milk or orange juice. The linear range of calibration curves for ricin were 0.5-300 ng/mL in PBS, 1.0-400 ng/mL in milk, and 1.0-250 ng/mL in orange juice. The method accuracy ranged between 82.6 and 101.8% for PBS, 88.9-105.2% for milk, and 95.3-118.7% for orange juice. The intra-day and inter-day precision had relative standard deviations (%RSD) of 0.3-9.4%, 0.7-8.9%, and 0.2-6.9% in the three matrices respectively. Furthermore, whether T7A or TG11B is used as a quantitative peptide, the quantitative results of ricin are consistent. This study provides not only a practical method for the absolute quantification of ricin in beverage matrices but also a new strategy for the investigation of illegal use of ricin in chemical weapon verification tasks such as OPCW biotoxin sample analysis exercises.


Assuntos
Bebidas/análise , Cromatografia Líquida de Alta Pressão/métodos , Ricina/análise , Espectrometria de Massas em Tandem/métodos , Tripsina/análise , Biotinilação , Calibragem , Marcação por Isótopo , Limite de Detecção , Magnetismo , Peptídeos/química , Controle de Qualidade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Solventes , Estreptavidina/análise
9.
Biosci Biotechnol Biochem ; 85(5): 1128-1139, 2021 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-33693487

RESUMO

The C-terminal of G protein-coupled receptors is now recognized as being important for G protein activation and signaling function. To detect the role of C-terminal tail in receptor activation, we used the α1b-AR, which has a long C-terminal of 164 amino acids. We constructed the intramolecular FRET sensors, in which the C-terminal was truncated to 10 (∆C-10), 20 (∆C-20), 30 (∆C-30), 50 (∆C-50), 70 (∆C-70), or 90 (∆C-90). The truncated mutants of ∆C-10, ∆C-20, or ∆C-30 cannot induce FRET signal changes and downstream ERK1/2 phosphorylation. However, the truncated mutants of ∆C-50, ∆C-70, or ∆C-90 induce significant FRET signal changes and downstream ERK1/2 phosphorylation, especially ∆C-90. This is particularly true in the case of the ∆C-90, ∆C-70, or ∆C-50 which retained the potential phosphorylation sites (Ser401, Ser404, Ser408, or Ser410). The ∆C-90 showed an increase in agonist-induced FRET signal changes and ERK1/2 phosphorylation in PKC- or endocytosis-dependent and EGFR-, src-, or ß-arrestin2-independent.


Assuntos
Técnicas Biossensoriais , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Processamento de Proteína Pós-Traducional , Receptores Adrenérgicos alfa 1/química , beta-Arrestina 2/genética , Animais , Transferência Ressonante de Energia de Fluorescência , Expressão Gênica , Genes Reporter , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Células HEK293 , Humanos , Mesocricetus , Proteína Quinase 1 Ativada por Mitógeno/genética , Proteína Quinase 3 Ativada por Mitógeno/genética , Fenilefrina/farmacologia , Fosforilação/efeitos dos fármacos , Plasmídeos/química , Plasmídeos/metabolismo , Domínios Proteicos , Engenharia de Proteínas/métodos , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Receptores Adrenérgicos alfa 1/genética , Receptores Adrenérgicos alfa 1/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Serina/metabolismo , beta-Arrestina 2/antagonistas & inibidores , beta-Arrestina 2/metabolismo
10.
Zhongguo Zhong Yao Za Zhi ; 46(22): 5736-5743, 2021 Nov.
Artigo em Zh | MEDLINE | ID: mdl-34951161

RESUMO

The medicinal plants with roots and rhizomes as the medicinal parts account for about 1/3 of Chinese medicinal herbs. Root and rhizome medicinal materials are widely used in clinical practice, whereas their wild resource reserves are insufficient to meet the market demand. With the expansion of planting areas, the formation of large-scale production areas, and the increase in planting years, diseases and insect pests of these medicinal plants, which are diverse and have broad transmission routes, strong concealment, and heavy damage, have become more and more serious. The prevention and control of these diseases and insect pests is characterized by multiple ways of pesticide application, large consumption of pesticides, susceptibility to soil barrier, difficulty in the control, and unstable control efficiency. Organophosphorus pesticides(OPPs) are widely used in the cultivation of Chinese medicinal plants because of their diverse varieties, broad-spectrum, good efficacy, and low residues, and have a positive effect on the yield and quality of Chinese medicinal materials. However, the abuse of OPPs not only increases the planting cost, but also affects the quality and safety of Chinese medicinal plants, the safety of clinical use of Chinese medicine, and the ecological safety of production areas. This paper reviewed the research and development progress of OPPs, the registration status of OPPs used in root and rhizome medicinal materials, residue limit standards, residue status, and rapid detection technology progress of OPPs. This review aims to provide research ideas and references for standardizing the use of OPPs in root and rhizome medicinal materials, reducing OPP residues, and establishing a fast, efficient, accurate, and reliable method for the detection of OPP residues in Chinese herbal medicine.


Assuntos
Resíduos de Praguicidas , Praguicidas , Plantas Medicinais , Compostos Organofosforados , Resíduos de Praguicidas/análise , Praguicidas/análise , Rizoma/química
11.
Eur Radiol ; 30(6): 3059-3065, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32064562

RESUMO

INTRODUCTION: We aimed to investigate the utility of compressed sensing time-of-flight magnetic resonance angiography (CS TOF-MRA) for diagnosing intracranial and cervical arterial stenosis by using digital subtraction angiography (DSA) as the reference standard. METHODS: Thirty-seven patients with head and neck arterial stenoses who underwent CS TOF-MRA and DSA were retrospectively enrolled. The reconstructed resolution of CS TOF-MRA was 0.4 × 0.4 × 0.4 mm3. The scan time was 5 min and 2 s. The image quality of CS TOF-MRA was independently ranked by two neuroradiologists in 1031 arterial segments. The luminal stenosis grades on CS TOF-MRA and DSA were analyzed in 61 arterial segments and were compared using the Wilcoxon signed-rank test. The ability of CS TOF-MRA to predict moderate to severe stenosis or occlusion was analyzed. RESULTS: The image quality of most arterial segments (95.2%) on CS TOF-MRA was excellent. Arterial segments with low image quality were mainly the V3-4 segments of the vertebral artery. The majority of arterial stenoses (62.3%) were located in the cervical internal carotid artery. The luminal stenosis grades of CS TOF-MRA were concordant with that of DSA in 50 of 61 segments (p = 0.366). CS TOF-MRA had a sensitivity of 84.4% and a specificity of 88.5% for predicting moderate to severe stenosis. For detecting occlusion lesions, it had a sensitivity of 100% and a specificity of 94.1%. CONCLUSION: CS TOF-MRA provides adequate image quality within a reasonable acquisition time and is a reliable tool for diagnosing head and neck arterial steno-occlusive disease. KEY POINTS: • CS TOF-MRA provides a relatively large coverage (16 cm), high resolution (0.4 × 0.4 × 0.4 mm3) and good image quality of head and neck arteries within 5 min and 2 s. • The diagnostic accuracy of CS TOF-MRA in the assessment of moderate to severe stenosis and occlusion was comparable with that of DSA. • Arterial segments with low image quality were mainly the V3 and V4 segments of the vertebral artery.


Assuntos
Angiografia Digital/métodos , Arteriopatias Oclusivas/diagnóstico , Artéria Carótida Interna/diagnóstico por imagem , Angiografia por Ressonância Magnética/métodos , Artéria Vertebral/diagnóstico por imagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Curva ROC , Reprodutibilidade dos Testes , Estudos Retrospectivos
12.
Pestic Biochem Physiol ; 134: 8-13, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27914544

RESUMO

Three rice planthoppers, brown planthopper, Nilaparvata lugens, white-backed planthopper, Sogatella furcifera and small brown planthopper, Laodelphax striatellus, are important pests of cultivated rice in tropical and temperate Asia. They have caused severe economic loss and developed resistance to insecticides from most chemical classes. Dinotefuran is the third neonicotinoid which possesses a broad spectrum and systemic insecticidal activity. We determined the susceptibility of dinotefuran to field populations from major rice production areas in China from 2013 to 2015. All the populations of S. furcifera and L. striatellus were kept susceptible to dinotefuran (0.7 to 1.4-fold of S. furcifera and 1.1-to 3.4-fold of L. striatellus) However, most strains of N. lugens (except FQ15) collected in 2015 had developed moderate resistance to dinotefuran, with resistance ratios (RR) ranging from 23.1 to 100.0 folds. Cross-resistance studies showed that chlorpyrifos-resistant and buprofezin-resistant Sogatella furcifera, chlorpyrifos-resistant and fipronil-resistant L. striatellus, imidacloprid-resistant and buprofezin-resistant Nilaparvata lugens exhibited negligible or no cross-resistance to dinotefuran. Synergism tests showed that piperonyl butoxide (PBO) produced a high synergism of dinotefuran effects in the DY15 and JS15 populations (2.14 and 2.52-fold, respectively). The obvious increase in resistance to dinotefuran in N. lugens indicates that insecticide resistance management strategies are urgently needed to prevent or delay further increase of insecticide resistance in N. lugens.


Assuntos
Guanidinas/toxicidade , Hemípteros/efeitos dos fármacos , Resistência a Inseticidas , Inseticidas/toxicidade , Nitrocompostos/toxicidade , Animais , China , Imidazóis/toxicidade , Neonicotinoides , Oryza , Sinergistas de Praguicidas/toxicidade , Butóxido de Piperonila/toxicidade , Pirazóis/toxicidade , Tiadiazinas/toxicidade
13.
Biomed Environ Sci ; 27(9): 676-83, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25256857

RESUMO

OBJECTIVE: This study was aimed to investigate the toxic effects of 3 nanomaterials, i.e. multi-walled carbon nanotubes (MWCNTs), graphene oxide (GO), and reduced graphene oxide (RGO), on zebrafish embryos. METHODS: The 2-h post-fertilization (hpf) zebrafish embryos were exposed to MWCNTs, GO, and RGO at different concentrations (1, 5, 10, 50, 100 mg/L) for 96 h. Afterwards, the effects of the 3 nanomateria on spontaneous movement, heart rate, hatching rate, length of larvae, mortality, and malformations ls were evaluated. RESULTS: Statistical analysis indicated that RGO significantly inhibited the hatching of zebrafish embryos. Furthermore, RGO and MWCNTs decreased the length of the hatched larvae at 96 hpf. No obvious morphological malformation or mortality was observed in the zebrafish embryos after exposure to the three nanomaterials. CONCLUSION: MWCNTs, GO, and RGO were all toxic to zebrafish embryos to influence embryos hatching and larvae length. Although no obvious morphological malformation and mortality were observed in exposed zebrafish embryos, further studies on the toxicity of the three nanomaterials are still needed.


Assuntos
Desenvolvimento Embrionário/efeitos dos fármacos , Grafite/toxicidade , Nanotubos de Carbono/toxicidade , Óxidos/toxicidade , Animais , Embrião não Mamífero , Feminino , Frequência Cardíaca/efeitos dos fármacos , Masculino , Movimento/efeitos dos fármacos , Testes de Toxicidade , Peixe-Zebra
14.
Foods ; 13(4)2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38397512

RESUMO

Pyrrolizidine alkaloids (PAs) are naturally occurring secondary metabolites of plants. To date, more than 660 types of PAs have been identified from an estimated 6000 plants, and approximately 120 of these PAs are hepatotoxic. As a result of PAs being found in spices, herbal teas, honey, and milk, PAs are considered contaminants in foods, posing a potential risk to human health. Here, we summarize the chemical structure, toxic effects, levels, and regulation of PAs in different countries to provide a better understanding of their toxicity and risk assessment. With recent research on the risk assessment of PAs, this review also discusses the challenges facing this field, aiming to provide a scientific basis for PA toxicity research and safety assessment.

15.
J Ethnopharmacol ; 327: 117982, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38423411

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Cynanchum otophyllum C.K.Schneid.PI.Wilson, commonly referred as ''Qingyangshen'' (QYS), is a traditional folk medicine from Yunnan, renowned for its efficacy in neurological and psychiatric disorders. Glycosides isolated from QYS have shown promise in alleviating epilepsy, however, mechanisms of action and specific molecular targets remain to be elucidated. AIM OF THE STUDY: The study aimed to evaluate the anticonvulsant effects of Qingyangshen glycosides M1 (M1), a C21 steroidal glycoside from QYS, on pentylenetetrazol (PTZ)-induced convulsions in zebrafish (Danio rerio), and its neuroprotective effect on Glutamate (Glu)-induced damage to PC12 cells, and importantly to identify its potential molecular targets. MATERIALS AND METHODS: To evaluate anticonvulsant activity of M1, 7 days-post-fertilization (7-dpf) animals were pretreated (by immersion) and then exposed to PTZ (10 mM) solution. Furthermore, Glu-induced PC12 cell damage was employed to investigate the neuroprotective and anti-apoptotic capacity. Cells were pretreated with various concentrations of M1 (0-10 µM) for 12 h and then co-treated with Glu (15 mM) for an additional 24 h. The cell viability, apoptosis rate and apoptosis-related proteins (p-PI3K, PI3K, Akt, p-Akt, CREB, p-CREB, BDNF, Bax and Bcl-2) were measured using CCK-8, annexin V/PI and Western blot assays. To model the expected interaction between M1 and candidate cannabinoid receptor type 1 (CB1R), ERK phosphorylation, molecular docking, and drug affinity responsive target stability (DARTS) techniques were employed. Finally, CB1R antagonist Rimonabant (Rim) was validated by co-administration in both zebrafish and cells to confirm the requirement of CB1R for M1 efficacy. RESULTS: At a concentration of 400 µM, M1 dramatically reversed PTZ-induced convulsive-like behaviors in zebrafish, as evidenced by a significant reduction in locomotor activity. In the context of Glu-induced cytotoxicity, M1 (10 µM) demonstrated a notable increase in cell viability and suppressed apoptosis through modulation of the Bax/Bcl-2 ratio and activation of the PI3K/Akt/CREB/BDNF signaling axis. These effects were facilitated through CB1R activation. In contrast, Rim dampened the beneficial activities of M1 as a cannabinoid agonist. CONCLUSIONS: These results demonstrated that M1 as a potential CB1R activator, exhibiting anticonvulsive effects in a PTZ-induced zebrafish model and neuroprotective properties via the PI3K/Akt/CREB/BDNF signaling axis in a Glu-induced PC12 cell injury model. Notably, the observed seizure relief attenuated by CB1R chemical antagonism.


Assuntos
Fármacos Neuroprotetores , Proteínas Proto-Oncogênicas c-akt , Humanos , Ratos , Animais , Proteínas Proto-Oncogênicas c-akt/metabolismo , Glicosídeos/farmacologia , Glicosídeos/uso terapêutico , Glicosídeos/química , Peixe-Zebra , Anticonvulsivantes/farmacologia , Anticonvulsivantes/uso terapêutico , Fosfatidilinositol 3-Quinases/metabolismo , Proteína X Associada a bcl-2 , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Simulação de Acoplamento Molecular , China , Convulsões/induzido quimicamente , Convulsões/tratamento farmacológico , Convulsões/metabolismo , Proteínas Reguladoras de Apoptose , Apoptose , Proteínas Proto-Oncogênicas c-bcl-2 , Pentilenotetrazol/toxicidade , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico
16.
Spectrochim Acta A Mol Biomol Spectrosc ; 286: 122021, 2023 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-36283209

RESUMO

A novel fluorescent sensor was developed in this study based on glutathione-functionalized graphene quantum dots (GQDs@GSH) to detect organophosphorus pesticide residues in Radix Angelica Sinensis. GQDs@GSH was synthesized by a one-step pyrolysis method with a fluorescence quantum yield as high as 33.9% and its structure was characterized by transmission electron microscopy and X-ray photoelectron spectroscopy. GQDs@GSH exhibited excellent fluorescence property showing strong blue fluorescence under UV irradiation. The fluorescence of GQDs@GSH could be quenched by Fe3+ by electron transfer and the quenched fluorescence could be recovered due to the strong chelating and reducing ability of phytic acid (PA). Under the catalyzation of acetylcholinesterase (AChE) and choline oxidase (ChOx), acetylcholine (ACh) could be decomposed to H2O2, which could further oxidize Fe2+ to Fe3+ thus quenching the fluorescence of GQDs@GSH once again. Coumaphos, a kind of organophosphorus pesticide, could inhibit AChE activity, thus making the quenched fluorescence turn on again. Several parameters influencing the fluorescence response such as Fe3+, PA, ACh and coumaphos concentration, pH value and reaction time were optimized. Based on such a fluorescence "off-on-off-on" ngkmechanism, GQDs@GSH was successfully applied to the detection of coumaphos in Radix Angelica Sinensis. A good linear relationship between the fluorescence intensity and coumaphos concentration was obtained in the range of 0.1-10.0 µmol·L-1. By a standard addition method, the recoveries were measured to be 101.44-117.90% with RSDs lower than 1.98%. The biosensor system is simple, sensitive and accurate. It has a good application prospect in the detection of organophosphorus pesticide residues in traditional Chinese medicine and agricultural products, and also expanded the application scope for glutathione as a highly selective biological molecule.


Assuntos
Angelica sinensis , Grafite , Resíduos de Praguicidas , Praguicidas , Pontos Quânticos , Pontos Quânticos/química , Grafite/química , Corantes Fluorescentes/química , Compostos Organofosforados , Acetilcolinesterase , Peróxido de Hidrogênio , Cumafos , Glutationa/química
17.
J Pharm Biomed Anal ; 231: 115410, 2023 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-37087773

RESUMO

In this work, novel potential anthraquinone-temozolomide (TMZ) antitumor hybrids N-(2-((9,10-dioxo-9,10-dihydroanthracen-1-yl)amino)ethyl)-3-methyl-4-oxo-3,4-dihydroimidazo [5, 1-d][1,2,3,5]tetrazine-8-carboxamide (C-1) and 2-(9,10-dioxo-9,10-dihydroanthracen-1-yl)amino) ethyl-3-methyl-4-oxo-3,4-dihydroimidazo[5,1-d][1,2,3,5]tetrazine-8-carboxylate (C-9) were designed and synthesized successfully. The electrochemical behaviors of C-1 (C-9) involved the reversible processes of 9,10-anthraquinone ring, the irreversible reduction and oxidation processes of TMZ ring. Electrochemical biosensors were constructed with ctDNA, poly (dG) and poly (dA) modifying the surface of glassy carbon electrode (GCE) to evaluate the DNA oxidative damage caused by the interaction of C-1 (C-9) with DNA. Anthracycline skeleton and TMZ ring in C-1 (C-9) could exhibit bifunctional effects with both intercalating and alkylation modes toward DNA strands. The DNA biosensor had good practicability in mouse serum. The results of gel electrophoresis further demonstrated that C-1 (C-9) could effectively intercalated into ctDNA and disrupt plasmid conformation. Finally, anthraquinone-TMZ hybrid C-1 possessed high cytotoxicity toward A549 and GL261 cells, which could be a novel and optimal candidate for the clinic antitumor treatment.


Assuntos
Antraquinonas , Técnicas Biossensoriais , Animais , Camundongos , Temozolomida , Carbono , DNA/química , Eletrodos , Técnicas Eletroquímicas/métodos
18.
J Ethnopharmacol ; 317: 116706, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-37301305

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Nonsteroidal anti-inflammatory drugs (NSAIDs) have been used clinically to treat inflammatory diseases clinically. However, the adverse effects of NSAIDs cannot be ignored. Therefore, it is critical for us to find alternative anti-inflammatory drugs that can reduce adverse reactions to herbal medicine, such as Iris tectorum Maxim., which has therapeutic effects and can treat inflammatory diseases and liver-related diseases. AIM OF THE STUDY: This study aimed to isolate active compounds from I. tectorum and investigate their anti-inflammatory effects and action mechanisms. MATERIALS AND METHODS: Fourteen compounds were isolated from I. tectorum using silica gel column chromatography, Sephadex LH-20, ODS and high performance liquid chromatography, and their structures were identified by examining physicochemical properties, ultraviolet spectroscopy, infrared spectroscopy, mass spectrometry, and nuclear magnetic resonance spectroscopy. Classical inflammatory cell models were established using lipopolysaccharide (LPS)-stimulated RAW264.7 cells and rat primary peritoneal macrophages to examine the effect of these compounds. To examine the action mechanisms, the nitric oxide (NO) levels were measured by Griess reagent and the levels of inflammatory cytokines in the supernatant were measured by ELISA; The expressions of major proteins in prostaglandin E2 (PGE2) synthesis and the nuclear factor-κB (NF-κB) and mitogen-activated protein kinase (MAPK) signaling pathways were examined by Western blotting, and the mRNA expression levels were measured by quantitative real-time polymerase chain reaction; and the nuclear translocation of p65 was examined by high content imaging. Molecular docking was used to predict the binding of active compound to target protein. RESULTS: Our findings revealed that Iristectorigenin C (IT24) significantly inhibited the levels of NO and PGE2 without affecting cyclooxygenase (COX)-1/COX-2 expression in LPS-induced RAW264.7 cells and rat peritoneal macrophages. Furthermore, IT24 was shown to decrease the expression of microsomal prostaglandin synthetase-1 (mPGES-1) in LPS-induced rat peritoneal macrophages. IT24 did not suppress the phosphorylation and nuclear translocation of proteins in the NF-κB pathway, but it inhibited the phosphorylation of p38/JNK in LPS-stimulated RAW264.7 cells. Additionally, molecular docking analysis indicated that IT24 may directly bind to the mPGES-1 protein. CONCLUSION: IT24 might inhibit mPGES-1 and the p38/JNK pathway to exert its anti-inflammatory effects and could be also developed as an inhibitor of mPGES-1 to prevent and treat mPGES-1-related diseases, such as inflammatory diseases, and holds promise for further research and drug development.


Assuntos
Lipopolissacarídeos , Sistema de Sinalização das MAP Quinases , Ratos , Animais , Lipopolissacarídeos/farmacologia , NF-kappa B/metabolismo , Simulação de Acoplamento Molecular , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios não Esteroides/farmacologia , Macrófagos Peritoneais , Ciclo-Oxigenase 2/metabolismo , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo
19.
Zhonghua Yi Xue Za Zhi ; 92(22): 1540-3, 2012 Jun 12.
Artigo em Zh | MEDLINE | ID: mdl-22944057

RESUMO

OBJECTIVE: To explore the clinical significance of trefoil factor 1 (TFF1) protein expression and serum pepsinogen (PG) concentration in benign and malignant gastric ulcers. METHODS: The TFF1 protein expression was evaluated by immunohistochemistry in biopsies of gastric mucosa from 18 normal controls, 25 patients with gastric ulcer and 13 patients with ulcerative gastric cancer at our hospital during January to June 2011. The serum concentrations of PGI and PGII were detected by enzyme-linked immunosorbent assay (ELISA) and PG/PGII (PGR) was subsequently calculated. RESULTS: The expression of TFF1 protein increased significantly in ulcerative and peripheral gastric mucosa and peripheral mucosa of gastric cancers versus that in normal controls and the ulcerocancer group (3.04% ± 0.20%, 3.00% ± 0.20%, 3.23% ± 0.26% vs 1.67% ± 0.18%, 0.46% ± 0.18%, all P < 0.01). The elevated expression of TFF1 increased the risk of gastric ulcer (OR: 1.365, 95%CI: 1.065 - 1.749, P = 0.014) while the down-regulation of TFF1 significantly increased the risk of ulcerocancer (OR: 3.067, 95%CI: 1.391 - 6.757, P = 0.005). The serum levels of PGI and PGII in gastric ulcer group were significantly higher than that in normal control and ulcerocancer group ((150 ± 27), (28 ± 9) vs (121 ± 22), (17 ± 7), (79 ± 12), (20 ± 5) µg/L,all P < 0.01). The PGI level and PGR decreased significantly in the ulcerocancer group versus normal control (both P < 0.01). But there was no statistical difference in PGII (P > 0.05). Receiver operating characteristic curve analysis revealed that PGI and PGR were valuable for the diagnosis of malignant gastric cancer with an area under curve of 0.975 and 0.914 respectively. CONCLUSIONS: The expression of TFF1 protein increases in gastric ulcer but decreases in gastric ulcerocancer. The elevated serum levels of PGI and PGII indicate benign ulcer while a marked decline of serum PG I and PGR serves as a risk signal of malignant gastric ulcer. The evaluation of expression profiles of TFF1 protein and PGs is helpful for the differentiation of benign gastric ulcer from malignant ulcerocancer.


Assuntos
Pepsinogênio A/sangue , Neoplasias Gástricas/sangue , Úlcera Gástrica/sangue , Proteínas Supressoras de Tumor/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Soro/metabolismo , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/patologia , Úlcera Gástrica/diagnóstico , Úlcera Gástrica/patologia , Fator Trefoil-1
20.
Artigo em Inglês | MEDLINE | ID: mdl-35742435

RESUMO

Ozone (O3), whose concentrations have been increasing in eastern China recently, plays a key role in human health, biodiversity, and climate change. Accurate information about the spatiotemporal distribution of O3 is crucial for human exposure studies. We developed a deep learning model based on a long short-term memory (LSTM) network to estimate the daily maximum 8 h average (MDA8) O3 across eastern China in 2020. The proposed model combines LSTM with an attentional mechanism and residual connection structure. The model employed total O3 column product from the Tropospheric Monitoring Instrument, meteorological data, and other covariates as inputs. Then, the estimates from our model were compared with real observations of the China air quality monitoring network. The results indicated that our model performed better than other traditional models, such as the random forest model and deep neural network. The sample-based cross-validation R2 and RMSE of our model were 0.94 and 10.64 µg m−3, respectively. Based on the O3 distribution over eastern China derived from the model, we found that people in this region suffered from excessive O3 exposure. Approximately 81% of the population in eastern China was exposed to MDA8 O3 > 100 µg m−3 for more than 150 days in 2020.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Aprendizado Profundo , Ozônio , Poluentes Atmosféricos/análise , Poluição do Ar/análise , China , Monitoramento Ambiental/métodos , Humanos , Ozônio/análise
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