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1.
J Biochem Mol Toxicol ; 38(6): e23734, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38764151

RESUMO

We explored the effects of curcumin on the aberrant biological behaviors of prolactinoma cells and the downstream pathways through which curcumin exerts its antitumor effects. We used quantitative reverse transcription-polymerase chain reaction assays to measure miR-206 expression levels in peripheral blood samples from patients with prolactinoma before and after curcumin treatment. We also investigated the proliferation level, viability, and invasion ability of groups of cells treated with different concentrations of curcumin using 3-(4,5)-dimethylthiahiazo (-z-y1)-3-di-phenytetrazoliumromide (MTT) assays, cell cloning assays, and Transwell assays, respectively. Furthermore, we determined the levels of autophagy-related proteins and protein kinase B/mammalian target of the rapamycin (Akt/mTOR) signaling pathway-related proteins in each group of treated cells by western blot. Curcumin treatment upregulated miR-206 expression levels in the peripheral blood of patients with prolactinoma and in GH3 cells. Knockdown of miR-206 expression enhanced the proliferation and invasive ability of GH3 cells, while curcumin treatment effectively inhibited the aberrant biological behavior of GH3 cells enhanced by miR-206 knockdown. miR-206 knockdown also activated the Akt/mTOR signaling pathway and inhibited autophagy in GH3 cells, and these changes were effectively reversed by curcumin treatment. Thus, curcumin inhibited the Akt/mTOR signaling pathway and promoted cell autophagy by miR-206 upregulation, resulting in antitumor effects that inhibited prolactinoma cell proliferation and invasion.


Assuntos
Antineoplásicos , Curcumina , MicroRNAs , Neoplasias Hipofisárias , Prolactinoma , Curcumina/administração & dosagem , Prolactinoma/sangue , Prolactinoma/tratamento farmacológico , Neoplasias Hipofisárias/sangue , Neoplasias Hipofisárias/tratamento farmacológico , Autofagia/efeitos dos fármacos , Regulação para Cima , Regulação da Expressão Gênica , MicroRNAs/sangue , MicroRNAs/genética , Transdução de Sinais , Antineoplásicos/administração & dosagem , Masculino , Feminino
2.
BMC Plant Biol ; 21(1): 599, 2021 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-34915868

RESUMO

BACKGROUND: Soil salinization extensively hampers the growth, yield, and quality of crops worldwide. The most effective strategies to counter this problem are a) development of crop cultivars with high salt tolerance and b) the plantation of salt-tolerant crops. Glycyrrhiza inflata, a traditional Chinese medicinal and primitive plant with salt tolerance and economic value, is among the most promising crops for improving saline-alkali wasteland. However, the underlying molecular mechanisms for the adaptive response of G. inflata to salinity stress remain largely unknown. RESULT: G. inflata retained a high concentration of Na+ in roots and maintained the absorption of K+, Ca2+, and Mg2+ under 150 mM NaCl induced salt stress. Transcriptomic analysis of G. inflata roots at different time points of salt stress (0 min, 30 min, and 24 h) was performed, which resulted in 70.77 Gb of clean data. Compared with the control, we detected 2645 and 574 differentially expressed genes (DEGs) at 30 min and 24 h post-salt-stress induction, respectively. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses revealed that G. inflata response to salt stress post 30 min and 24 h was remarkably distinct. Genes that were differentially expressed at 30 min post-salt stress induction were enriched in signal transduction, secondary metabolite synthesis, and ion transport. However, genes that were differentially expressed at 24 h post-salt-stress induction were enriched in phenylpropane biosynthesis and metabolism, fatty acid metabolism, glycerol metabolism, hormone signal transduction, wax, cutin, and cork biosynthesis. Besides, a total of 334 transcription factors (TFs) were altered in response to 30 min and 24 h of salt stress. Most of these TFs belonged to the MYB, WRKY, AP2-EREBP, C2H2, bHLH, bZIP, and NAC families. CONCLUSION: For the first time, this study elucidated the salt tolerance in G. inflata at the molecular level, including the activation of signaling pathways and genes that regulate the absorption and distribution of ions and root growth in G. inflata under salt stress conditions. These findings enhanced our understanding of the G. inflata salt tolerance and provided a theoretical basis for cultivating salt-tolerant crop varieties.


Assuntos
Glycyrrhiza/crescimento & desenvolvimento , Transporte de Íons , Raízes de Plantas/crescimento & desenvolvimento , Estresse Salino , Absorção Fisico-Química , Regulação da Expressão Gênica de Plantas , Ontologia Genética , Glycyrrhiza/metabolismo , Sequenciamento de Nucleotídeos em Larga Escala , Raízes de Plantas/metabolismo , RNA-Seq , Tolerância ao Sal , Sódio/metabolismo , Transcriptoma
3.
J Cell Physiol ; 235(3): 2060-2070, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31318049

RESUMO

This study aims to determine whether caveolin-1 (Cav-1) participates in the process of diabetic neuropathic pain by directly regulating the expression of toll-like receptor 4 (TLR4) and the subsequent phosphorylation of N-methyl-D-aspartate receptor 2B subunit (NR2B) in the spinal cord. Male Sprague-Dawley rats (120-150 g) were continuously fed with high-fat and high-sugar diet for 8 weeks, and received a single low-dose of intraperitoneal streptozocin injection in preparation for the type-II diabetes model. Then, these rats were divided into five groups according to the level of blood glucose, and the mechanical withdrawal threshold and thermal withdrawal latency values. The pain thresholds were measured at 3, 7, and 14 days after animal grouping. Then, eight rats were randomly chosen from each group and killed. Lumbar segments 4-6 of the spinal cord were removed for western blot analysis and immunofluorescence assay. Cav-1 was persistently upregulated in the spinal cord after diabetic neuropathic pain in rats. The downregulation of Cav-1 through the subcutaneous injection of Cav-1 inhibitor daidzein ameliorated the pain hypersensitivity and TLR4 expression in the spinal cord in diabetic neuropathic pain (DNP) rats. Furthermore, it was found that Cav-1 directly bound with TLR4, and the subsequent phosphorylation of NR2B in the spinal cord contributed to the modulation of DNP. These findings suggest that Cav-1 plays a vital role in DNP processing at least in part by directly regulating the expression of TLR4, and through the subsequent phosphorylation of NR2B in the spinal cord.


Assuntos
Caveolina 1/metabolismo , Neuropatias Diabéticas/metabolismo , Dor/metabolismo , Transdução de Sinais/fisiologia , Receptor 4 Toll-Like/metabolismo , Animais , Diabetes Mellitus Experimental/induzido quimicamente , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Tipo 2/induzido quimicamente , Diabetes Mellitus Tipo 2/metabolismo , Modelos Animais de Doenças , Masculino , Limiar da Dor/fisiologia , Ratos , Ratos Sprague-Dawley , Medula Espinal/metabolismo , Estreptozocina/farmacologia
4.
Tumour Biol ; 39(5): 1010428317701632, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28466784

RESUMO

Long non-coding RNAs have recently emerged as important regulators in the pathogenesis and progression of cancers. The long non-coding RNA urothelial carcinoma-associated 1 is reportedly upregulated and functions as an oncogene in some tumors. However, the role of urothelial carcinoma-associated 1 in renal cell carcinoma is not well elucidated so far. In this study, we found that urothelial carcinoma-associated 1 was overexpressed in renal cell carcinoma tissues compared with the adjacent normal tissues, and higher urothelial carcinoma-associated 1 expression levels were positively associated with advanced tumor stage and poor survival time in renal cell carcinoma patients. Further studies showed that knockdown of urothelial carcinoma-associated 1 suppressed renal cell carcinoma cell proliferation and S-phase cell number in vitro. Moreover, urothelial carcinoma-associated 1 was found to be associated with enhancer of zeste homolog 2, which suppressed p21 expression through histone methylation (H3K27me3) on p21 promoter. We also showed that knockdown of urothelial carcinoma-associated 1 increased the p21 protein expression through regulating enhancer of zeste homolog 2. In addition, bioinformatics analysis and dual-luciferase reporter assays confirmed that miR-495 was a target of urothelial carcinoma-associated 1 in renal cell carcinoma, and urothelial carcinoma-associated 1 promoted cell proliferation by negatively regulating miR-495. These findings illuminated that urothelial carcinoma-associated 1 promoted renal cell carcinoma progression through enhancer of zeste homolog 2 and interacted with miR-495. Overall, overexpression of urothelial carcinoma-associated 1 functions as an oncogene in renal cell carcinoma that may offer a novel therapeutic target for renal cell carcinoma patients.


Assuntos
Carcinoma de Células Renais/genética , Proteína Potenciadora do Homólogo 2 de Zeste/genética , MicroRNAs/biossíntese , RNA Longo não Codificante/genética , Adulto , Idoso , Apoptose/genética , Carcinoma de Células Renais/patologia , Linhagem Celular Tumoral , Proliferação de Células , Metilação de DNA/genética , Epigênese Genética/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , MicroRNAs/genética , Pessoa de Meia-Idade , Regiões Promotoras Genéticas
5.
Bioorg Med Chem Lett ; 27(9): 1907-1910, 2017 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-28351591

RESUMO

This study investigated the anti-hepatoma activity of different extracts from A. squamosa pericarps, phytochemistry of the ethyl acetate (EtOAc) fraction and possible anti-hepatoma mechanism of active constituents. The anti-hepatoma activity of different extracts from A. squamosa pericarps were evaluated by MTT assay against SMMC-7721 cells in vitro and verified by using H22 xenografts bearing mice. Phytochemical investigation of the active pericarp extract was carried out. The pro-apoptosis and cycle arrest effects of active constituents were observed by fluorescent microscope and flow cytometry. Western blot assay was conducted to find the possible anti-hepatoma mechanisms of active constituents. The result showed that EtOAc extract was the active fraction. Two ent-kaurane diterpenoids, named ent-kauran-16-en-19-oic acid and ent-kauran-15-en-19-oic acid, were isolated from the active EtOAc fraction. The pro-apoptosis and G1 phase arrest effects of these diterpenoids were found. Western blot assay showed that ent-kauran-16-en-19-oic acid could activate caspase-3,-8,-9, up-regulate of Bax and down-regulate of Bcl-2.


Assuntos
Annona/química , Antineoplásicos Fitogênicos/uso terapêutico , Carcinoma Hepatocelular/tratamento farmacológico , Diterpenos do Tipo Caurano/uso terapêutico , Neoplasias Hepáticas/tratamento farmacológico , Fígado/efeitos dos fármacos , Animais , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Diterpenos do Tipo Caurano/química , Diterpenos do Tipo Caurano/isolamento & purificação , Diterpenos do Tipo Caurano/farmacologia , Humanos , Fígado/patologia , Neoplasias Hepáticas/patologia , Camundongos
6.
Exp Cell Res ; 340(1): 22-31, 2016 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-26708616

RESUMO

Excessive apoptosis of hematopoietic precursors in the bone marrow underlies the ineffective hematopoiesis characteristic of myelodysplastic syndrome (MDS). Toll-like receptor (TLR) signaling is abnormally activated in MDS and may be involved in excessive programmed cell death in the pathogenesis of MDS. TLRs expression and global histone H3/H4 acetylation were analyzed in bone marrow (BM) CD34+ cells from 20 lower-risk and 20 higher-risk MDS patients and 10 healthy controls. Apoptosis of BM CD34+ cells was examined by flow cytometry, and its correlation to histone acetylation and the expression of TLR2 and ß-arrestin1 (ß-arr1), measured by enzyme-linked immunosorbent assay and qRT-PCR, was assessed. TLR1, TLR2 and TLR6 expression and H4 acetylation levels were higher in lower-risk MDS patients than in higher-risk MDS patients or controls, and TLR2 expression and H4 acetylation levels were positively correlated with an increased rate of apoptosis. Lower-risk MDS was associated with increased ß-arr1 expression and histone acetyltransferase p300 activity. In in vitro-cultured primary normal and lower-risk MDS CD34+ cells, TLR2 activation-induced apoptosis was mediated by the upregulation of ß-arr1 leading to the recruitment of p300 and increased histone H4 acetylation. The nuclear accumulation of ßarr1 following TLR2 activation promote H4 acetylation at specific target gene promoters and may thus affect transcription of target genes in BM CD34+ cells. The mechanisms underlying the deregulation of TLR2 and increased apoptosis in MDS may involve the ß-arr1 mediated recruitment of p300 leading to increased levels of histone H4 acetylation.


Assuntos
Antígenos CD34/metabolismo , Apoptose , Arrestinas/metabolismo , Histonas/metabolismo , Síndromes Mielodisplásicas/metabolismo , Síndromes Mielodisplásicas/patologia , Receptores Toll-Like/metabolismo , Acetilação , Histonas/química , Humanos , Regulação para Cima , beta-Arrestina 1 , beta-Arrestinas
7.
Gynecol Endocrinol ; 33(8): 621-624, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28361552

RESUMO

OBJECTIVE: To analyze the concentrations of nesfatin-1 in maternal and cord serum, to evaluate the expression of nesfatin-1 in subcutaneous adipose tissue (SAT) from pregnant women with gestational diabetes mellitus (GDM) and those with normal glucose tolerance (NGT). METHODS: We studied a total of 50 GDM and 50 NGT subjects. The clinical features, serum nesfatin-1, homeostasis model assessment of insulin resistance (HOMA-IR), lipid profiles were measured at the third trimester of pregnancy. The expression of nesfatin-1 in the SAT was determined by western blot. RESULTS: Compared with the NGT group, the GDM group showed greater levels of serum nesfatin-1, adipocyte fatty acid binding protein (AFABP), and leptin; a greater level of cord blood nesfatin-1; and a higher level of expression in SAT (p < 0.05 or p < 0.01). Fasting insulin (FI) (b = 0.317, p= 0.022) and body mass index (BMI) before delivery (b = 0.367, p=0.008) were independently associated with serum nesfatin-1. Nesfatin-1 was the independent risk factor for GDM. CONCLUSIONS: The GDM group had higher levels of maternal serum and cord blood nesfatin-1, and greater nesfatin-1 expression in SAT. Nesfatin-1 is closely related to obesity and IR in pregnancy.


Assuntos
Proteínas de Ligação ao Cálcio/sangue , Proteínas de Ligação a DNA/sangue , Diabetes Gestacional/sangue , Proteínas do Tecido Nervoso/sangue , Regulação para Cima , Adulto , Povo Asiático , Biomarcadores/sangue , Biomarcadores/metabolismo , Glicemia/análise , Índice de Massa Corporal , Proteínas de Ligação ao Cálcio/metabolismo , China , Proteínas de Ligação a DNA/metabolismo , Diabetes Gestacional/metabolismo , Ensaio de Imunoadsorção Enzimática , Proteínas de Ligação a Ácido Graxo/sangue , Proteínas de Ligação a Ácido Graxo/metabolismo , Feminino , Sangue Fetal/metabolismo , Humanos , Insulina/sangue , Resistência à Insulina , Leptina/sangue , Leptina/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Nucleobindinas , Gravidez , Gordura Subcutânea Abdominal/metabolismo , Adulto Jovem
8.
J Med Syst ; 41(8): 126, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28718051

RESUMO

Coronary heart disease preoperative diagnosis plays an important role in the treatment of vascular interventional surgery. Actually, most doctors are used to diagnosing the position of the vascular stenosis and then empirically estimating vascular stenosis by selective coronary angiography images instead of using mouse, keyboard and computer during preoperative diagnosis. The invasive diagnostic modality is short of intuitive and natural interaction and the results are not accurate enough. Aiming at above problems, the coronary heart disease preoperative gesture interactive diagnostic system based on Augmented Reality is proposed. The system uses Leap Motion Controller to capture hand gesture video sequences and extract the features which that are the position and orientation vector of the gesture motion trajectory and the change of the hand shape. The training planet is determined by K-means algorithm and then the effect of gesture training is improved by multi-features and multi-observation sequences for gesture training. The reusability of gesture is improved by establishing the state transition model. The algorithm efficiency is improved by gesture prejudgment which is used by threshold discriminating before recognition. The integrity of the trajectory is preserved and the gesture motion space is extended by employing space rotation transformation of gesture manipulation plane. Ultimately, the gesture recognition based on SRT-HMM is realized. The diagnosis and measurement of the vascular stenosis are intuitively and naturally realized by operating and measuring the coronary artery model with augmented reality and gesture interaction techniques. All of the gesture recognition experiments show the distinguish ability and generalization ability of the algorithm and gesture interaction experiments prove the availability and reliability of the system.


Assuntos
Doença das Coronárias , Gestos , Algoritmos , Mãos , Humanos , Reprodutibilidade dos Testes
9.
Small ; 11(15): 1792-800, 2015 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-25581016

RESUMO

Surface modification or decoration of ultrathin MoS2 films with chemical moieties is appealing since nanointerfacing can functionalize MoS2 films with bonus potentials. In this work, a facile and effective method for microlandscaping of Au nanoparticles (NPs) on few-layer MoS2 films is developed. This approach first employs a focused laser beam to premodify the MoS2 films to achieve active surface domains with unbound sulfur. When the activated surface is subsequently immersed in AuCl3 solution, Au NPs are found to preferentially decorate onto the modified regions. As a result, Au NPs can be selectively and locally anchored onto designated regions on the MoS2 surface. With a scanning laser beam, microlandscapes comprising of Au NPs decorated on laser-defined micropatterns are constructed. By varying the laser power, reaction time and thickness of the MoS2 films, the size and density of the NPs can be controlled. The resulting hybrid materials are demonstrated as efficient Raman active surfaces for the detection of aromatic molecules with high sensitivity.


Assuntos
Dissulfetos/química , Ouro/química , Hidrocarbonetos Aromáticos/análise , Nanopartículas Metálicas/química , Nanopartículas Metálicas/ultraestrutura , Molibdênio/química , Análise Espectral Raman/métodos , Adsorção , Hidrocarbonetos Aromáticos/química , Teste de Materiais , Tamanho da Partícula , Propriedades de Superfície
10.
Guang Pu Xue Yu Guang Pu Fen Xi ; 34(10): 2645-51, 2014 Oct.
Artigo em Zh | MEDLINE | ID: mdl-25739201

RESUMO

Partial least squares (PLS) and radial basis function neural network (RBFNN) combined with near infrared spectros- copy (NIR) were applied to develop models for cordycepic acid, polysaccharide and adenosine analysis in Paecilomyces hepialid fermentation mycelium. The developed models possess well generalization and predictive ability which can be applied for crude drugs and related productions determination. During the experiment, 214 Paecilomyces hepialid mycelium samples were obtained via chemical mutagenesis combined with submerged fermentation. The contents of cordycepic acid, polysaccharide and adenosine were determined via traditional methods and the near infrared spectroscopy data were collected. The outliers were removed and the numbers of calibration set were confirmed via Monte Carlo partial least square (MCPLS) method. Based on the values of degree of approach (Da), both moving window partial least squares (MWPLS) and moving window radial basis function neural network (MWRBFNN) were applied to optimize characteristic wavelength variables, optimum preprocessing methods and other important variables in the models. After comparison, the RBFNN, RBFNN and PLS models were developed successfully for cordycepic acid, polysaccharide and adenosine detection, and the correlation between reference values and predictive values in both calibration set (R2c) and validation set (R2p) of optimum models was 0.9417 and 0.9663, 0.9803 and 0.9850, and 0.9761 and 0.9728, respectively. All the data suggest that these models possess well fitness and predictive ability.


Assuntos
Paecilomyces/química , Espectroscopia de Luz Próxima ao Infravermelho , Adenosina/análise , Calibragem , Fermentação , Análise dos Mínimos Quadrados , Modelos Teóricos , Micélio/química , Redes Neurais de Computação , Polissacarídeos/análise
11.
Comput Struct Biotechnol J ; 24: 247-257, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38617891

RESUMO

Objectives: Combination therapy of lenvatinib and immune checkpoint inhibitors (CLICI) has emerged as a promising approach for managing unresectable hepatocellular carcinoma (HCC). However, the response to such treatment is observed in only a subset of patients, underscoring the pressing need for reliable methods to identify potential responders. Materials & methods: This was a retrospective analysis involving 120 patients with unresectable HCC. They were divided into training (n = 72) and validation (n = 48) cohorts. We developed an interpretable deep learning model using multiphase computed tomography (CT) images to predict whether patients will respond or not to CLICI treatment, based on the Response Evaluation Criteria in Solid Tumors, version 1.1 (RECIST v1.1). We evaluated the models' performance and analyzed the impact of each CT phase. Critical regions influencing predictions were identified and visualized through heatmaps. Results: The multiphase model outperformed the best biphase and uniphase models, achieving an area under the curve (AUC) of 0.802 (95% CI = 0.780-0.824). The portal phase images were found to significantly enhance the model's predictive accuracy. Heatmaps identified six critical features influencing treatment response, offering valuable insights to clinicians. Additionally, we have made this model accessible via a web server at http://uhccnet.com/ for ease of use. Conclusions: The integration of multiphase CT images with deep learning-generated heatmaps for predicting treatment response provides a robust and practical tool for guiding CLICI therapy in patients with unresectable HCC.

12.
Aging (Albany NY) ; 15(17): 8613-8629, 2023 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-37702613

RESUMO

Gastric cancer possesses high lethality rate, and its complex molecular mechanisms of pathogenesis lead to irrational treatment outcomes. Autophagy plays a dual role in cancer by both promoting and suppressing the cancer. However, the role of autophagy in gastric cancer is still vague. Therefore, in this study, we first obtained autophagy-related genes from the Human Autophagy Database, and then applied consensus clustering analysis to analyse the molecular subtypes of gastric cancer samples in the TCGA database. The genes obtained after subtyping were then applied to construct risk prognostic model. Following this, PCA and tSNE assessed risk scores with good discriminatory ability for gastric cancer samples. The results of Cox regression analysis and time-dependent ROC curve analysis indicated that the model had good risk prediction ability. Finally, NRP1 was selected as the final study subject in the context of expression pairwise analysis, Kaplan-Meier curves and external validation of the GEO dataset. In vitro experiments showed that NRP1 has the ability to regulate the proliferation and autophagy of gastric cancer cells by affecting the Wnt/ß-catenin signalling pathway. Similarly, in vivo experiments have shown that NRP1 can affect tumour growth in vivo. We therefore propose that NRP1 can be used as both a prognostic factor and a therapeutic target through the regulation of autophagy in gastric cancer.


Assuntos
Neoplasias Gástricas , Humanos , Autofagia/genética , Proliferação de Células/genética , Neoplasias Gástricas/genética , Via de Sinalização Wnt/genética
13.
Huan Jing Ke Xue ; 44(1): 75-84, 2023 Jan 08.
Artigo em Zh | MEDLINE | ID: mdl-36635797

RESUMO

Liucheng county, as a suburb of Liuzhou City in Guangxi province, has a prominent ozone (O3) pollution problem; however, there have been no relevant analyses of the cause of local O3 pollution reported. In order to investigate the causes of O3 pollution, an online observation of 116 VOCs with a time resolution of 1 h was carried out in Liucheng county from October 1st to 15th, and the sensitivity of ozone to the relative changes in the NOx and VOCs was analyzed. The results showed that the average value of φï¼»total volatile organic compounds (TVOCs)ï¼½ during the observation period was 27.52×10-9, and the average value of φ(TVOCs) during the polluting process (October 1st to 6th) was 32.15×10-9, which was 32.79% higher than that of the non-pollution process (October 8th to 15th). In terms of species concentration, oxygenated volatile organic compounds (OVOCs) contributed the highest, accounting for 43.70%, followed by alkanes (23.00%), aromatics (11.75%), and halocarbons (7.35%). In terms of ozone formation potential (OFP), OVOCs contributed the highest (41.96%) to OFP, followed by aromatics (32.60%) and alkenes (17.92%). During the observation period, VOCs mainly came from motor vehicle emissions (32.44%), biomass combustion sources (29.31%), solvent use sources (16.43%), plant sources (11.34%), and chemical industry emissions (10.49%). The contribution ratios of solvent use sources and plant sources in the pollution process increased by 28.58% and 28.53%, respectively. The EKMA curve shows that, during the observation period, Liucheng county was in a synergistic control area for VOCs and nitric oxide (NOx). Therefore, in the high ozone-occurrence autumn of Liucheng county, the key will be to reduce both VOCs and NOx emissions.


Assuntos
Poluentes Atmosféricos , Ozônio , Compostos Orgânicos Voláteis , Ozônio/análise , Poluentes Atmosféricos/análise , Compostos Orgânicos Voláteis/análise , Monitoramento Ambiental/métodos , China , Emissões de Veículos/análise , Solventes/análise , Óxido Nítrico/análise
14.
World J Microbiol Biotechnol ; 28(3): 993-1002, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22805820

RESUMO

An analytical procedure has been developed for at-line (fast off-line) monitoring of 4 key parameters including nisin titer (NT), the concentration of reducing sugars, cell concentration and pH during a nisin fermentation process. This procedure is based on near infrared (NIR) spectroscopy and Partial Least Squares (PLS). Samples without any preprocessing were collected at intervals of 1 h during fifteen batch of fermentations. These fermentation processes were implemented in 3 different 5 l fermentors at various conditions. NIR spectra of the samples were collected in 10 min. And then, PLS was used for modeling the relationship between NIR spectra and the key parameters which were determined by reference methods. Monte Carlo Partial Least Squares (MCPLS) was applied to identify the outliers and select the most efficacious methods for preprocessing spectra, wavelengths and the suitable number of latent variables (n (LV)). Then, the optimum models for determining NT, concentration of reducing sugars, cell concentration and pH were established. The correlation coefficients of calibration set (R (c)) were 0.8255, 0.9000, 0.9883 and 0.9581, respectively. These results demonstrated that this method can be successfully applied to at-line monitor of NT, concentration of reducing sugars, cell concentration and pH during nisin fermentation processes.


Assuntos
Lactococcus lactis/crescimento & desenvolvimento , Lactococcus lactis/metabolismo , Nisina/metabolismo , Biotecnologia/métodos , Meios de Cultura/química , Fermentação , Concentração de Íons de Hidrogênio , Modelos Estatísticos , Espectroscopia de Luz Próxima ao Infravermelho/métodos
15.
Chemosphere ; 294: 133778, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35093421

RESUMO

Flame retardancy and recyclability are two important issues in the research field of thermosets, particularly for epoxy resin (EP) with the biggest market share. It is of great importance, but rarely achievable, to integrate these properties simultaneously into EP. Herein, we report a facile way to prepare intrinsically flame-retardant epoxy vitrimers combining rapid recycling and multiple shape memory effects by introducing dynamic ester-linkages with catalytic transesterification activity into the crosslinking networks of EP. The flame-retardant epoxy vitrimers exhibited high Tg (∼110.7 °C), desirable thermal stability and excellent flame retardancy with UL-94 V-0 rating, and high LOI of ∼34%. Also, the value of the peak heat release rate (PHRR) and the total heat release (THR) showed 63% and 32% reduction, respectively. Meanwhile, flame-retardant epoxy vitrimers showed high malleability that could be reprocessed in 15 min at 200 °C without sacrificing the mechanical properties and flame retardancy. Moreover, the dynamic transesterification network allowed flame-retardant EP to access multiple shape memory effect. The design of flame-retardant epoxy vitrimers provide a prime example to foster the cyclic utilization of flame-retardant thermosetting polymers.


Assuntos
Resinas Epóxi , Retardadores de Chama , Catálise , Temperatura Alta , Polímeros
16.
J Hazard Mater ; 436: 129272, 2022 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-35739787

RESUMO

Frequent oil spills have caused severe environmental and ecological damage. Effective cleanup has become a complex challenge owing to the poor flowability of viscous crude oils. The current method of solar heating to reduce the viscosity of heavy oil is only suitable during sunny days, while the use of Joule heating is limited by the risk of direct exposure to high-voltage electricity. Herein, we demonstrate a noncontact electromagnetic induction and solar dual-heating sponge for the quick, safe, and energy-saving cleanup of ultrahigh-viscosity heavy oil. The resulting sponge with magnetic, conductive, and hydrophobic properties can be rapidly heated to absorb heavy oil under alternating magnetic fields, solar irradiation, or both of these conditions. By constructing theoretical models and fitting the actual data, an in-depth analysis of induction and solar heating processes is carried out. The sponge has excellent resilience and stability, indicating its reusability, fast and continuous adsorption (16.17 g in 10 s), and large capacity (75-81 g/g, the highest value ever) for soft asphalt (a highly viscous crude oil). This work provides a new noncontact dual-heating strategy for heavy oil cleanup, in which absorbents use induction heating during an emergency and then switch to partial or full solar heating to save energy in sunny conditions. ENVIRONMENTAL IMPLICATION: Heavy oils stranded on the beach or floating on water can kill underwater plants by blocking sunlight, or trap water birds and other animals. Heavy oil also contains aromatic substances that are toxic to aquatic organisms. Although oil spills near shallow water cannot be cleaned up by fences or other machinery, an oil adsorbent can deal with this problem. However, common adsorbents cannot effectively absorb high-viscosity oils, such as heavy oil. In this paper, an induction and solar dual-heating sponge is developed for the effective cleanup of high-viscosity oil.


Assuntos
Poluição por Petróleo , Petróleo , Energia Solar , Animais , Óleos/química , Poluição por Petróleo/análise , Luz Solar , Viscosidade , Água/química
17.
Research (Wash D C) ; 2022: 9846940, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36299449

RESUMO

Covalent adaptable networks (CANs) combine the uniqueness of thermoplastics and thermosets to allow for reprocessability while being covalently crosslinked. However, it is highly desirable but rarely achieved for CANs to simultaneously demonstrate reversibility and mechanical robustness. Herein, we report a feasible strategy to develop a novel epoxy vitrimer (EV) composed of adaptable phosphate networks (APNs), by which the EVs exhibit promising mechanical properties (tensile strength of 62.5 ~ 87.8 MPa and tensile modulus of 1360.1 ~ 2975.3 MPa) under ambient conditions. At elevated temperatures, the topology rearrangement occurs relied on phosphate transesterification, which contributes to the shape memory performance, self-healing, reprocessing, and welding behaviors. Moreover, the incorporation of APNs allows for improvements in anti-ignition and also the inhibition of both heat release and smoke generation to avoid empyrosis, asphyxiation, and toxication during burning, showing expected intrinsic fire safety. Thermal, mechanical properties, and flame retardancy of the reprocessed EVs after hot pressing are very close to those of the original EVs, which is attributed to the sufficient reversibility of APNs. Accordingly, combining the aforementioned features, EVs are manufactured as flame-triggered switches for fire alarms, which symbolizes the innovative development of high-performance covalent adaptable polymeric materials.

19.
Nat Prod Res ; 34(15): 2243-2247, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30835539

RESUMO

In the present study, five new ent-kaurane diterpenes including 4α-hydroxy-17,19-dinor-ent-kaurane-16-one (1), 4ß-hydroxy-16ß-H-18-nor-ent-kaurane-17-oic acid (2), 4ß,17-dihydroxy-16α-acetoxy-18-nor-ent-kaurane (3), Annosquamosin Z (4) and 16α-H-ent-kaurane-17,18-dioic acid, 17-methy ester (5) were isolated from Annona squamosa L. pericarp. The compounds were also evaluated for their cytotoxic activities against SMMC-7721 and HepG2 cell lines, among which compound 3 exhibited potent cytotoxicity with IC50 value of less than 20 µM.


Assuntos
Annona/química , Diterpenos do Tipo Caurano/isolamento & purificação , Citotoxinas/isolamento & purificação , Citotoxinas/farmacologia , Diterpenos , Diterpenos do Tipo Caurano/toxicidade , Células Hep G2 , Humanos , Concentração Inibidora 50
20.
Am J Transl Res ; 12(8): 4819-4829, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32913553

RESUMO

OBJECTIVE: Diabetic neuropathic pain (DNP) is one of the common complications in type 2 Diabetes Mellitus (DM) patients. However, molecular mechanisms in underlying diabetic neuropathic pain are still poorly understood. Kalirin-7, a multifunctional Rho GDP/GTP exchange factor, located at the excitatory synapses, was reported to modulate the neuronal cytoskeleton. Therefore, in this study, we explored the effects of Kalirin-7 on type 2 diabetic neuropathic pain and the mechanisms in spinal cord in rats. METHODS: The type 2 diabetic neuropathic pain model was established in rats by feeding them with a high-sugar and high-fat diet for 8 weeks, and then fasting them for 12 hours, followed by a single intraperitoneal injection of STZ. Kalirin-7 was knocked down in the spinal cord by an intrathecal administration of Kalirin-7 siRNA. RESULTS: The levels of Kalirin-7, p-NR2B and PSD-95 as well as the PSD-95-NR2B coupling were significantly increased in the spinal cord of type 2 DM rats. The knockdown of Kalirin-7 expression in the spinal cord by the intrathecal administration of Kalirin-7 siRNA not only reduced the levels of p-NR2B and the PSD-95-NR2B coupling in the spinal cord, but also relieved mechanical allodynia and thermal hyperalgesia in type 2 DM rats. CONCLUSIONS: Our findings suggest that spinally expressed Kalirin-7 likely contributes to type 2 diabetic neuropathic pain through regulating the PSD-95/NR2B interaction-dependent NR2B phosphorylation in the spinal cord.

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