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1.
Bioinformatics ; 40(1)2024 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-38141207

RESUMO

MOTIVATION: The utilization of single-cell bisulfite sequencing (scBS-seq) methods allows for precise analysis of DNA methylation patterns at the individual cell level, enabling the identification of rare populations, revealing cell-specific epigenetic changes, and improving differential methylation analysis. Nonetheless, the presence of sparse data and an overabundance of zeros and ones, attributed to limited sequencing depth and coverage, frequently results in reduced precision accuracy during the process of differential methylation detection using scBS-seq. Consequently, there is a pressing demand for an innovative differential methylation analysis approach that effectively tackles these data characteristics and enhances recognition accuracy. RESULTS: We propose a novel beta mixture approach called scDMV for analyzing methylation differences in single-cell bisulfite sequencing data, which effectively handles excess zeros and ones and accommodates low-input sequencing. Our extensive simulation studies demonstrate that the scDMV approach outperforms several alternative methods in terms of sensitivity, precision, and controlling the false positive rate. Moreover, in real data applications, we observe that scDMV exhibits higher precision and sensitivity in identifying differentially methylated regions, even with low-input samples. In addition, scDMV reveals important information for GO enrichment analysis with single-cell whole-genome sequencing data that are often overlooked by other methods. AVAILABILITY AND IMPLEMENTATION: The scDMV method, along with a comprehensive tutorial, can be accessed as an R package on the following GitHub repository: https://github.com/PLX-m/scDMV.


Assuntos
Metilação de DNA , Sulfitos , Análise de Sequência de DNA/métodos , Sequenciamento Completo do Genoma
2.
Brief Bioinform ; 23(6)2022 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-36124777

RESUMO

A transcriptional regulatory network (TRN) is a collection of transcription regulators with their associated downstream genes, which is highly condition-specific. Understanding how cell states can be programmed through small molecules/drugs or conditions by modulating the whole gene expression system granted us the potential to amend abnormal cells and cure diseases. Condition Orientated Regulatory Networks (CORN, https://qinlab.sysu.edu.cn/home) is a library of condition (small molecule/drug treatments and gene knockdowns)-based transcriptional regulatory sub-networks (TRSNs) that come with an online TRSN matching tool. It allows users to browse condition-associated TRSNs or match those TRSNs by inputting transcriptomic changes of interest. CORN utilizes transcriptomic changes data after specific conditional treatment in cells, and in vivo transcription factor (TF) binding data in cells, by combining TF binding information and calculations of significant expression alterations of TFs and genes after the conditional treatments, TRNs under the effect of different conditions were constructed. In short, CORN associated 1805 different types of specific conditions (small molecule/drug treatments and gene knockdowns) to 9553 TRSNs in 25 human cell lines, involving 204TFs. By linking and curating specific conditions to responsive TRNs, the scientific community can now perceive how TRNs are altered and controlled by conditions alone in an organized manner for the first time. This study demonstrated with examples that CORN can aid the understanding of molecular pathology, pharmacology and drug repositioning, and screened drugs with high potential for cancer and coronavirus disease 2019 (COVID-19) treatments.


Assuntos
COVID-19 , Redes Reguladoras de Genes , Humanos , COVID-19/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Transcriptoma
3.
Respir Res ; 25(1): 233, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38840238

RESUMO

BACKGROUND: There is inconclusive evidence to suggest that the expression of programmed cell death ligand 1 (PD-L1) is a putative predictor of response to EGFR-TKI therapy in advanced EGFR-mutant non-small cell lung cancer (NSCLC). We evaluated the heterogeneity in PD-L1 expression in the primary lung site and metastatic lymph nodes to analyze the association between PD-L1 expression and response for patients treated with EGFR-TKI. METHODS: This study reviewed 184 advanced NSCLC patients with EGFR mutations who received first-generation EGFR-TKI as first-line treatment from 2020 to 2021 at Shanghai Chest Hospital. The patients were divided into the primary lung site group (n = 100) and the metastatic lymph nodes group (n = 84) according to the biopsy site. The patients in each group were divided into TPS < 1%, TPS 1-49%, and TPS ≥ 50% groups according to PD-L1 expression. RESULTS: The median PFS was 7 (95% CI: 5.7-8.3) months, and the median OS was 26 (95% CI: 23.5-28.5) months for all patients. No correlation existed between PFS or OS and PD-L1 expression. The median PFS in the primary lung site group was 11 months (95% CI: 9.6-12.4) in the TPS < 1% group, 8 months (95% CI: 6.6-9.4) in TPS 1-49% group, and 4 months (95% CI: 3.2-4.8) in TPS ≥ 50% group, with statistically significant differences (p = 0.000). The median OS of the TPS < 1% group and TPS ≥ 50% group showed a statistically significant difference (p = 0.008) in the primary lung site group. In contrast, PD-L1 expression in the lymph nodes of EGFR-mutant patients was unrelated to PFS or OS after EGFR-TKI therapy. CONCLUSION: PD-L1 expression from the primary lung site might predict clinical benefit from EGFR-TKI, whereas PD-L1 from metastatic lymph nodes did not. TRIAL REGISTRATION: This retrospective study was approved by the Ethics Committee of Shanghai Chest Hospital (ID: IS23060) and performed following the Helsinki Declaration of 1964 (revised 2008).


Assuntos
Antígeno B7-H1 , Carcinoma Pulmonar de Células não Pequenas , Receptores ErbB , Neoplasias Pulmonares , Metástase Linfática , Inibidores de Proteínas Quinases , Humanos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Antígeno B7-H1/biossíntese , Antígeno B7-H1/antagonistas & inibidores , Antígeno B7-H1/metabolismo , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Feminino , Masculino , Pessoa de Meia-Idade , Receptores ErbB/biossíntese , Receptores ErbB/genética , Receptores ErbB/metabolismo , Receptores ErbB/antagonistas & inibidores , Idoso , Inibidores de Proteínas Quinases/uso terapêutico , Estudos Retrospectivos , Linfonodos/patologia , Linfonodos/efeitos dos fármacos , Linfonodos/metabolismo , Adulto , Idoso de 80 Anos ou mais , Resultado do Tratamento , Valor Preditivo dos Testes , Mutação , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/biossíntese , Biomarcadores Tumorais/metabolismo , Biomarcadores Tumorais/análise
4.
Cell Biochem Funct ; 42(4): e4032, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38736209

RESUMO

Polymerase chain reaction (PCR) is an important tool for exogenous gene acquisition and recombinants identification. There exist two problems when using Serratia marcescens as a template for PCR amplification: amplified PCR products are rapidly degraded, and the results of PCR amplification are unstable. The aim of the present work was to elucidate the reasons for this. By mixing PCR products amplified from Escherichia coli DH5α with S. marcescens supernatant or pellet, we found that the DNA-degrading substance in S. marcescens is thermally resistant and present both intracellularly and extracellularly. We then determined that it is protein, and most likely S. marcescens nuclease, that degrades PCR products since the addition of SDS and EDTA can effectively inhibit or block the degradation of PCR products. By knocking out the S. marcescens nuclease encoding gene, nucA, we confirmed that the nuclease is responsible for the degradation of PCR products and the instability of PCR amplification. This work is the first to show that the S. marcescens nuclease is temporarily and partially inhibited by high temperatures during PCR and recovers rapidly at room temperature after PCR.


Assuntos
Reação em Cadeia da Polimerase , Serratia marcescens , Serratia marcescens/enzimologia , Serratia marcescens/genética , Serratia marcescens/metabolismo , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/genética , Escherichia coli/metabolismo , Escherichia coli/genética , Temperatura Alta , Temperatura
5.
Int J Cancer ; 153(3): 635-643, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37078587

RESUMO

Treatments for NSCLC patients with EGFR-TKI resistance are limited. Given that immunotherapy and antiangiogenic agents may have synergistic antitumor effects, we aimed to analyze the effect of multi-target angiogenesis inhibitor anlotinib and immune checkpoint inhibitors (ICIs) combination therapy in NSCLC patients who failed EGFR-TKI. The medical records of lung adenocarcinoma (LUAD) patients with EGFR-TKI resistance were reviewed. After EGFR-TKI resistance, patients who simultaneously received anlotinib and ICIs were enrolled in the observation group, and those who received platinum-pemetrexed chemotherapy were included in the control group. A total of 80 LUAD patients were reviewed and allocated to the anlotinib and ICIs combination therapy (n = 38) and chemotherapy (n = 42) groups. A re-biopsy was performed in all patients in the observation group before the administration of anlotinib and ICIs. The median follow-up was 15.63 months (95% CI: 12.19-19.08). Combination therapy exhibited better PFS (median PFS: 4.33 months [95% CI: 2.62-6.05] vs 3.60 months [95% CI: 2.48-4.73], P = .005), and better OS (median OS: 14.17 months [95% CI: 10.17-18.17] vs 9.00 months [95% CI: 6.92-11.08], P = .029) than chemotherapy. Most patients (73.7%) received combination therapy as fourth and later lines of therapy, with a median PFS of 4.03 months (95% CI: 2.05-6.02) and a median OS of 13.80 months (95% CI: 8.25-19.36). The disease control rate was 92.1%. Four patients discontinued the combination therapy due to adverse events, but the other adverse reactions were manageable and reversible. The combination of anlotinib and PD-1 inhibitors is a promising regimen for the late-line treatment of LUAD patients with EGFR-TKI resistance.


Assuntos
Adenocarcinoma de Pulmão , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Adenocarcinoma de Pulmão/tratamento farmacológico , Inibidores da Angiogênese/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/patologia , Receptores ErbB/genética , Inibidores de Checkpoint Imunológico/uso terapêutico , Neoplasias Pulmonares/patologia , Mutação , Inibidores de Proteínas Quinases/uso terapêutico
6.
Brief Bioinform ; 22(6)2021 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-34374760

RESUMO

Cell fate conversion by overexpressing defined factors is a powerful tool in regenerative medicine. However, identifying key factors for cell fate conversion requires laborious experimental efforts; thus, many of such conversions have not been achieved yet. Nevertheless, cell fate conversions found in many published studies were incomplete as the expression of important gene sets could not be manipulated thoroughly. Therefore, the identification of master transcription factors for complete and efficient conversion is crucial to render this technology more applicable clinically. In the past decade, systematic analyses on various single-cell and bulk OMICs data have uncovered numerous gene regulatory mechanisms, and made it possible to predict master gene regulators during cell fate conversion. By virtue of the sparse structure of master transcription factors and the group structure of their simultaneous regulatory effects on the cell fate conversion process, this study introduces a novel computational method predicting master transcription factors based on group sparse optimization technique integrating data from multi-OMICs levels, which can be applicable to both single-cell and bulk OMICs data with a high tolerance of data sparsity. When it is compared with current prediction methods by cross-referencing published and validated master transcription factors, it possesses superior performance. In short, this method facilitates fast identification of key regulators, give raise to the possibility of higher successful conversion rate and in the hope of reducing experimental cost.


Assuntos
Biologia Computacional/métodos , Genômica/métodos , Análise de Célula Única/métodos , Algoritmos , Animais , Sítios de Ligação , Linhagem da Célula/genética , Fenômenos Fisiológicos Celulares/genética , Sequenciamento de Cromatina por Imunoprecipitação , Biologia Computacional/normas , Células-Tronco Embrionárias/citologia , Células-Tronco Embrionárias/metabolismo , Elementos Facilitadores Genéticos , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Genômica/normas , Humanos , Camundongos , Regiões Promotoras Genéticas , Ligação Proteica , Análise de Célula Única/normas , Fatores de Transcrição/metabolismo , Transcriptoma , Fluxo de Trabalho
7.
Biochem Biophys Res Commun ; 606: 135-141, 2022 05 28.
Artigo em Inglês | MEDLINE | ID: mdl-35349822

RESUMO

Neuroendocrine transdifferentiation (NED) of prostate cancer (PCa) is the main cause of failure of androgen receptor inhibitor treatment. However, the molecular mechanisms underlying the development of NEPC, especially treatment-induced NEPC, remain unclear. Emerging evidence indicates that elevated monoamine oxidase A (MAOA) contribute to the proliferation, cell stemness, and bone metastasis in PCa. Here, we generated an enzalutamide-induced NED cell model to assess the role of MAOA during NED. Overall, MAOA expression was significantly increased upon Enz long-term exposure and was required for neuroendocrine marker expression. In particular, Enz was found to induce NED via the MAOA/mTOR/HIF-1α signaling axis. Further analyses revealed that the MAOA inhibitor clorgyline(CLG) may bring multiple benefits to CRPC patients, including better therapeutic effect and delays NED. These findings suggest that MAOA may be an important target for the development of anti-NED therapies, thereby providing a novel strategy for the combined application of CLG and AR inhibitors in the clinic.


Assuntos
Transdiferenciação Celular , Monoaminoxidase , Neoplasias da Próstata , Linhagem Celular Tumoral , Humanos , Masculino , Monoaminoxidase/genética , Monoaminoxidase/metabolismo , Neoplasias da Próstata/patologia , Transdução de Sinais
8.
BMC Genomics ; 18(1): 908, 2017 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-29178828

RESUMO

BACKGROUND: Crustacea, the second largest subphylum of Arthropoda, includes species of major ecological and economic importance, such as crabs, lobsters, crayfishes, shrimps, and barnacles. With the rapid development of crustacean aquaculture and biodiversity loss, understanding the gene regulatory mechanisms of growth, reproduction, and development of crustaceans is crucial to both aquaculture development and biodiversity conservation of this group of organisms. In these biological processes, transcription factors (TFs) play a vital role in regulating gene expression. However, crustacean transcription factors are still largely unknown, because the lack of complete genome sequences of most crustacean species hampers the studies on their transcriptional regulation on a system-wide scale. Thus, the current TF databases derived from genome sequences contain TF information for only a few crustacean species and are insufficient to elucidate the transcriptional diversity of such a large animal group. RESULTS: Our database CrusTF ( http://qinlab.sls.cuhk.edu.hk/CrusTF ) provides comprehensive information for evolutionary and functional studies on the crustacean transcriptional regulatory system. CrusTF fills the knowledge gap of transcriptional regulation in crustaceans by exploring publicly available and newly sequenced transcriptomes of 170 crustacean species and identifying 131,941 TFs within 63 TF families. CrusTF features three categories of information: sequence, function, and evolution of crustacean TFs. The database enables searching, browsing and downloading of crustacean TF sequences. CrusTF infers DNA binding motifs of crustacean TFs, thus facilitating the users to predict potential downstream TF targets. The database also presents evolutionary analyses of crustacean TFs, which improve our understanding of the evolution of transcriptional regulatory systems in crustaceans. CONCLUSIONS: Given the importance of TF information in evolutionary and functional studies on transcriptional regulatory systems of crustaceans, this database will constitute a key resource for the research community of crustacean biology and evolutionary biology. Moreover, CrusTF serves as a model for the construction of TF database derived from transcriptome data. A similar approach could be applied to other groups of organisms, for which transcriptomes are more readily available than genomes.


Assuntos
Crustáceos/genética , Bases de Dados Genéticas , Fatores de Transcrição/fisiologia , Transcriptoma , Animais , Filogenia , Fatores de Transcrição/química , Fatores de Transcrição/classificação , Fatores de Transcrição/genética
9.
Sensors (Basel) ; 17(2)2017 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-28146128

RESUMO

A new structure bulk tobacco curing barn was presented. To study the temperature and humidity field in the new structure tobacco curing barn, a 3D transient computational fluid dynamics (CFD) model was developed using porous medium, species transport, κ-ε turbulence and discrete phase models. The CFD results demonstrated that (1) the temperature and relative humidity predictions were validated by the experimental results, and comparison of simulation results with experimental data showed a fairly close agreement; (2) the temperature of the bottom and inlet area was higher than the top and outlet area, and water vapor concentrated on the top and outlet area in the barn; (3) tobacco loading density and thickness of tobacco leaves had an explicit effect on the temperature distributions in the barn.

10.
Proc Natl Acad Sci U S A ; 110(48): 19615-20, 2013 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-24218580

RESUMO

Rickettsiae are responsible for some of the most devastating human infections. A high infectivity and severe illness after inhalation make some rickettsiae bioterrorism threats. We report that deletion of the exchange protein directly activated by cAMP (Epac) gene, Epac1, in mice protects them from an ordinarily lethal dose of rickettsiae. Inhibition of Epac1 suppresses bacterial adhesion and invasion. Most importantly, pharmacological inhibition of Epac1 in vivo using an Epac-specific small-molecule inhibitor, ESI-09, completely recapitulates the Epac1 knockout phenotype. ESI-09 treatment dramatically decreases the morbidity and mortality associated with fatal spotted fever rickettsiosis. Our results demonstrate that Epac1-mediated signaling represents a mechanism for host-pathogen interactions and that Epac1 is a potential target for the prevention and treatment of fatal rickettsioses.


Assuntos
Aderência Bacteriana/efeitos dos fármacos , Fatores de Troca do Nucleotídeo Guanina/antagonistas & inibidores , Interações Hospedeiro-Patógeno/fisiologia , Hidrazonas/farmacologia , Isoxazóis/farmacologia , Infecções por Rickettsia/tratamento farmacológico , Transdução de Sinais/fisiologia , Animais , Aderência Bacteriana/fisiologia , Fatores de Troca do Nucleotídeo Guanina/metabolismo , Células Endoteliais da Veia Umbilical Humana , Humanos , Hidrazonas/uso terapêutico , Imuno-Histoquímica , Isoxazóis/uso terapêutico , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Infecções por Rickettsia/metabolismo
11.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(2): 515-9, 2016 Feb.
Artigo em Zh | MEDLINE | ID: mdl-27209760

RESUMO

Hyperspectral imaging feature on potato leaves stressed by late blight was studied in the present paper. The experiment used 60 potato leaves. Among those 60 potato leaves, 48 leaves were vitro inoculated with pathogen of potato late blight, the rest 12 leaves were used as control samples. The leaves were observed for 7 continuous days before and after inoculated and samples including healthy and infested were acquired. Hyperspectral data of healthy and infected potato samples of different disease severity were obtained by the hyperspectral imaging system from 374 to 1,018 nm and then extract spectral data of region of interest (ROI) from those hyperspectral data by the ENVI software. In order to improve the signal-to-noise ratio, the spectral data were preprocessed using different pretreatment methods such as moving average smoothing, normalization, derivative, baseline etc. The least squares-support vector machine(LS-SVM) models were developed based on the raw and those preprocessed data. Among the nine models, the model that used the raw data and the data after the spectroscopic transformation performed best with the discrimination of 94.87%. It was demonstrated that it is realized to determine the potato late blight disease of different disease severity using hyperspectral imaging technique.


Assuntos
Doenças das Plantas , Folhas de Planta/microbiologia , Solanum tuberosum/microbiologia , Análise Espectral
12.
Methods ; 67(3): 294-303, 2014 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-24650566

RESUMO

Inferring gene regulatory networks from gene expression data at whole genome level is still an arduous challenge, especially in higher organisms where the number of genes is large but the number of experimental samples is small. It is reported that the accuracy of current methods at genome scale significantly drops from Escherichia coli to Saccharomyces cerevisiae due to the increase in number of genes. This limits the applicability of current methods to more complex genomes, like human and mouse. Least absolute shrinkage and selection operator (LASSO) is widely used for gene regulatory network inference from gene expression profiles. However, the accuracy of LASSO on large genomes is not satisfactory. In this study, we apply two extended models of LASSO, L0 and L1/2 regularization models to infer gene regulatory network from both high-throughput gene expression data and transcription factor binding data in mouse embryonic stem cells (mESCs). We find that both the L0 and L1/2 regularization models significantly outperform LASSO in network inference. Incorporating interactions between transcription factors and their targets remarkably improved the prediction accuracy. Current study demonstrates the efficiency and applicability of these two models for gene regulatory network inference from integrative omics data in large genomes. The applications of the two models will facilitate biologists to study the gene regulation of higher model organisms in a genome-wide scale.


Assuntos
Perfilação da Expressão Gênica/métodos , Redes Reguladoras de Genes , Algoritmos , Imunoprecipitação da Cromatina/métodos , Genoma , Modelos Genéticos
13.
Mar Drugs ; 12(5): 2790-801, 2014 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-24824025

RESUMO

Angiogenesis is the formation of blood vessels from pre-existing vasculature. Excessive or uncontrolled angiogenesis is a major contributor to many pathological conditions whereas inhibition of aberrant angiogenesis is beneficial to patients with pathological angiogenesis. Catunaregin is a core of novel marine compound isolated from mangrove associate. The potential anti-angiogenesis of catunaregin was investigated in human umbilical vein endothelial cells (HUVECs) and zebrafish. HUVECs were treated with different concentrations of catunaregin in the presence or absence of VEGF. The angiogenic phenotypes including cell invasion cell migration and tube formation were evaluated following catunaregin treatment in HUVECs. The possible involvement of AKT, eNOS and ERK1/2 in catunaregin-induced anti-angiogenesis was explored using Western blotting. The anti-angiogenesis of catunaregin was further tested in the zebrafish embryo neovascularization and caudal fin regeneration assays. We found that catunaregin dose-dependently inhibited angiogenesis in both HUVECs and zebrafish embryo neovascularization and zebrafish caudal fin regeneration assays. In addition, catunaregin significantly decreased the phosphorylation of Akt and eNOS, but not the phosphorylation of ERK1/2. The present work demonstrates that catunaregin exerts the anti-angiogenic activity at least in part through the regulation of the Akt and eNOS signaling pathways.


Assuntos
Inibidores da Angiogênese/farmacologia , Catecóis/farmacologia , Lignanas/farmacologia , Óxido Nítrico Sintase Tipo III/efeitos dos fármacos , Proteína Oncogênica v-akt/efeitos dos fármacos , Nadadeiras de Animais/efeitos dos fármacos , Nadadeiras de Animais/crescimento & desenvolvimento , Animais , Catecóis/química , Movimento Celular/efeitos dos fármacos , Embrião não Mamífero , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Humanos , Lignanas/química , Fosforilação/efeitos dos fármacos , Regeneração/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Fator A de Crescimento do Endotélio Vascular/farmacologia , Peixe-Zebra
14.
Guang Pu Xue Yu Guang Pu Fen Xi ; 34(4): 922-6, 2014 Apr.
Artigo em Zh | MEDLINE | ID: mdl-25007601

RESUMO

The objectives of this study were: (1) to optimize a near-infrared (NIR) spectroscopy model for fresh jujube stored at room temperature to predict the quality change (yeast growth), (2) to establish a kinetic model of yeast growth for fresh jujubes at room temperature according to NIR spectroscopy data and storage time, and (3) to predict the shelf life of fresh jujube at room temperature. The Lizao samples of fresh jujubes were adopted as the research object in the study. The NIR spectral data were achieved before yeast infection level measured. In order to optimize the NIR model, the pretreatment techniques such as Savitzky-Golay smoothing (S-G smoothing), multiplicative scatter correction (MSC), first derivative (1-Der) and second derivative (2-Der) were compared with the raw spectra by using a statistical software package (Unscrambler 9.8), and the regression coefficient (RC) method was used to choose the characteristic wavenumber. Multiple linear regression (MLR) was applied as NIR modeling method. According to the predicted yeast infection level using NIR model, the chemical kinetic models of spectral data and storage time at room temperature with zero-order and first-order reaction were established by using a statistical software package (SPSS 18). The shelf life could be predicted based on the chemical kinetic model. The results showed that the characteristic wave numbers of 10 300, 8 330, 6 900, 5 666, 5 150 and 4 060 cm(-1) in the whole near-infrared range with MSC technique could be chosen to model the quality deterioration of fresh jujube at room temperature. The NIR model that produced the best prediction had the form of B = 320.027 - 233.920(chi1) - 206.663(chi2) - 61.584(chi3) - 14.847(chi4) - 2.680(chi5) - 9.131(chi6), where B is yeast value (lg/cfu x g(-1)), chi1-chi6 are absorbance value of characteristic wavenumber. The correlation coefficient of calibration (R(c)) was 0.950, the root mean square error of calibration (RMSEC) was 2. 560, the correlation coefficient of prediction (R(p)) was 0.863, and the root mean square error of prediction (RMSEP) was 2.447. The zero-order reaction kinetic model performed better than the first-order model. The zero-order reaction kinetic model of yeast growth with storage time was predicted by B(t) = 171.395-124.445(chi1) - 109.945(chi2) - 32.763(chi3) - 7.899(chi4) - 1.426(chi5) - 4.857(chi6) + 0.045t with a correlation coefficient of 0.996. Based on the linear correlation between the NIR measurement and storage time, the shelf life of fresh jujube at room temperature was predicted to be 8 days for the yeast infection level less than 10 cfu x g(-1). The study showed that the NIR when combed with kinetic models could be used as a non-destructive, rapid method to detect the yeast growth in fresh jujube, and to predict the shelf life and ensure the quality and safety of fresh jujube.


Assuntos
Saccharomyces cerevisiae/isolamento & purificação , Ziziphus/microbiologia , Frutas/microbiologia , Cinética , Modelos Lineares , Espectroscopia de Luz Próxima ao Infravermelho
15.
Int J Biol Macromol ; 258(Pt 1): 128848, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38114003

RESUMO

The survival benefit for patients with gastric cancer (GC) is modest due to its high transfer potential. Targeted therapy for metastasis-related genes in GC may be a viable approach, however, inhibitors specifically targeting GC are limited. In this study, GC patient-derived xenografts (PDX) with metastatic burden were established via orthotopic transplantation. PCR-Array analysis of primary and metastatic tumors revealed EPH receptor B2 (EPHB2) as the most significantly upregulated gene. The interaction between the EPHB2 receptor and its cognate-specific EFNB1 ligands was high in GC and correlated with a poor prognosis. Fc-EFNB1 treatment increased the invasion and migration abilities of GC cells and induced a high EPHB2 expression. EPHB2 knockdown in GC cells completely abolished the ephrin ligand-induced effects on invasion and migration abilities. Signal transduction analysis revealed Wnt/ß-catenin and FAK as downstream signaling mediators potentially inducing the EPHB2 phenotype. In conclusion, the observed deregulation of EPHB2/EFNB1 expression in GC enhances the invasive phenotype, suggesting a potential role of EPHB2/EFNB1 compound in local tumor cell invasion and the formation of metastasis.


Assuntos
Receptor EphB2 , Neoplasias Gástricas , Humanos , Receptor EphB2/genética , Receptor EphB2/metabolismo , Neoplasias Gástricas/patologia , Efrina-B1/genética , Efrina-B1/metabolismo , beta Catenina/metabolismo , Ligantes , Via de Sinalização Wnt , Movimento Celular/genética , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Proliferação de Células/genética
16.
Sensors (Basel) ; 13(11): 15673-81, 2013 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-24248281

RESUMO

Fresh jujube (Ziziphus jujube) is rich in vitamin C, which is an important quality index and generally decreases with storage time. The aim of this study was to build kinetic models for determining the vitamin C content, thus predicting the quality characteristics and shelf life of fresh jujube. The quality changes of the jujube stored at room temperature (20 °C) were analyzed using near-infrared spectroscopy. The significant spectra were determined and a calibration model for vitamin C content was developed. The results showed that vitamin C content could be described by the zero-order kinetics model based on the regressions. In addition, the shelf life of the jujube at room temperature was calculated according to the regression model.


Assuntos
Ácido Ascórbico/análise , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Ziziphus/química , Conservação de Alimentos , Frutas/química , Cinética , Modelos Teóricos
17.
Guang Pu Xue Yu Guang Pu Fen Xi ; 33(12): 3231-4, 2013 Dec.
Artigo em Zh | MEDLINE | ID: mdl-24611376

RESUMO

There are many fresh jujube varieties. The different variety has different quality. In addition, dehiscent fruit easily rot and the rotten fruit contaminated the full fruit very rapidly. It is necessary to discriminate the jujube varieties and dehiscent fruit to reduce the storage loss. The objective is to discriminate varieties and dehiscent Fruit of fresh jujube using near infrared (NIR) spectroscopy. Two jujube varieties were investigated. Smoothing, multiplicative scatter correction, the first derivative and second derivative methods were adopted to pretreat the spectra. The regression coefficient and principal component analysis were used to select wavenumber. Multilayer perceptron artificial neural network was used to build varieties and dehiscent fruit qualitative discrimination model. The results showed that the varieties and dehiscent fruit could be correctly discriminated and both the discrimination accuracy rates were 100%. Hence, near infrared spectroscopy could achieve to identify the variety of Dongzao and Lizao, and dehiscent fruit and intact fruit.


Assuntos
Frutas , Espectroscopia de Luz Próxima ao Infravermelho , Ziziphus/classificação , Análise de Alimentos , Modelos Teóricos , Redes Neurais de Computação , Análise de Componente Principal
18.
Bioorg Med Chem Lett ; 22(12): 4038-43, 2012 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-22607683

RESUMO

Exchange proteins directly activated by cAMP (Epac) are a family of guanine nucleotide exchange factors that regulate a wide variety of intracellular processes in response to second messenger cAMP. To explore the structural determinants for Epac antagonist properties of high throughput screening (HTS) hit ESI-08, pyrimidine 1, a series of 5-cyano-6-oxo-1,6-dihydro-pyrimidine analogues have been synthesized and evaluated for their activities for Epac inhibition. Structure-activity relationship (SAR) analysis led to the identification of three more potent Epac antagonists (6b, 6g, and 6h). These inhibitors may serve as valuable pharmacological probes for further elucidation of the physiological functions and mechanisms of Epac regulation. Our SAR results and molecular docking studies have also revealed that further optimization of the moieties at the C-6 position of pyrimidine scaffold may allow us to discover more potent Epac-specific antagonists.


Assuntos
AMP Cíclico/farmacologia , Fatores de Troca do Nucleotídeo Guanina/antagonistas & inibidores , Nitrilas/síntese química , Pirimidinas/síntese química , Simulação por Computador , AMP Cíclico/metabolismo , Fatores de Troca do Nucleotídeo Guanina/química , Fatores de Troca do Nucleotídeo Guanina/metabolismo , Células HEK293 , Ensaios de Triagem em Larga Escala , Humanos , Modelos Moleculares , Nitrilas/farmacologia , Fosforilação , Isoformas de Proteínas/antagonistas & inibidores , Isoformas de Proteínas/química , Isoformas de Proteínas/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Pirimidinas/farmacologia , Transdução de Sinais/efeitos dos fármacos , Bibliotecas de Moléculas Pequenas , Relação Estrutura-Atividade
19.
Molecules ; 17(9): 10470-93, 2012 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-22945027

RESUMO

In the present study a universally applicable HPLC-DAD/ESI-MS/MS method was developed for carrying out the comprehensive characterization of Jitai tablets (JTT). Based on the ESI-MS(n) fragmentation patterns of the reference standards, a total of 101 components were identified or tentatively characterized by comparing their retention times, UV and MS spectra with those of reference standards or through the matching of empirical information with those of published components in the in-house library. The characteristic fragmentation pattern of alkaloids, phenolic acids, tanshinones, flavonoid glycosides, cyanogenic glycosides, ginsenosides, 2-(2-phenylethyl) chromones, phthalides and gingerol-related compounds were tentatively elucidated using structurally-relevant product ions. It was observed that neutral losses of C(9)H(10)O(3) and C(9)H(8)O(2) were the characteristic product ions of scopola alkaloids. Neutral fragment mandelonitrile was the characteristic ion of cyanogenic glycosides. To our knowledge, tropylium ion and C(4)H(2)O unit were the characteristic ions of 2-(2-phenylethyl) chromone, which resulted from the Retro-Diels-Alder (RDA) cleavage of the C ring. The results indicated that the developed analysis method could be employed as a rapid, effective technique for structural characterization of chemical constituents in TCM. This work is expected to provide comprehensive information for the quality evaluation and pharmacokinetic studies of JTT.


Assuntos
Medicamentos de Ervas Chinesas/química , Cromatografia Líquida de Alta Pressão , Estrutura Molecular , Transtornos Relacionados ao Uso de Opioides/tratamento farmacológico , Espectrometria de Massas por Ionização por Electrospray , Síndrome de Abstinência a Substâncias/tratamento farmacológico
20.
J Clin Med ; 12(1)2022 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-36615124

RESUMO

OBJECTIVE: Type 2 diabetes mellitus (T2DM) is the most common metabolic disease and is characterized by sustained hyperglycemia. The impact of T2DM on the survival of lung cancer patients remains controversial. The aim of this study was to investigate the associations of type 2 diabetes with lung cancer mortality. METHODS: From January 2019 to January 2020, 228 patients with non-small cell lung cancer (NSCLC) staging earlier than IIIA were included. RESULTS: In our study, we found that the overall survival (OS) and progression-free survival (PFS) of lung cancer patients with diabetes was longer than non-diabetes group. Diagnosed T2DM was associated with the prognosis of lung cancer after adjusting for age and covariates. The association between T2DM and OS was influenced by age, stage of cancer and cancer treatment, as well as whether taking metformin was associated with the OS of lung cancer. However, with the adjustment for age and covariates, the relation trended to lose statistical significance. CONCLUSION: T2DM is an independent prognostic factor for patients with NSCLC staging before IIIA. The patients with both NSCLC and T2DM trended to having a longer OS, possibly due to metformin.

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