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1.
Food Chem ; 460(Pt 2): 140620, 2024 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-39094338

RESUMO

Food contamination has long plagued agriculture, posing significant health risks to consumers. The use of volatile gases for food safety detection has proven highly effective, with composite gas sensors that leverage the two-dimensional material MXene exhibiting notable advancements in detecting various target gases. This paper reviews the progress of MXene-based composite gas sensors in the detection of food safety-related gases. The review begins by examining MXene material synthesis methods and then presents an overview of techniques aimed at enhancing MXene-based sensor detection capabilities. Recently, advancements in MXene composite gas sensors tailored for food safety gases have been highlighted. Finally, challenges encountered in gas-sensing applications of MXene-based composites are outlined, alongside predictions for their future development, aiming to offer insights for the application and advancement of intelligent gas sensors for target gases in food safety.


Assuntos
Contaminação de Alimentos , Inocuidade dos Alimentos , Gases , Gases/análise , Contaminação de Alimentos/análise
2.
J Food Sci ; 89(8): 5016-5030, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38980966

RESUMO

To improve the classification and regression performance of the total volatile basic nitrogen (TVB-N) and acid value (AV) of different freshness fish meal samples detected by a metal-oxide semiconductor electronic nose (MOS e-nose), 402 original features, 62 manually extracted features, manually extracted and selected features by the RFRFE method, and the features extracted by the long short-term memory (LSTM) network were used as inputs to identify the freshness. The classification performance of the freshness grades and the estimation performance of the TVB-N and AV values of fish meal with different freshness were compared. According to the sensor response curve, preprocessing and feature extraction steps were first applied to the original data. Then, five classification algorithms and four regression algorithms were used for modeling. The results showed that a total of 30 features were extracted using the LSTM network, and the number of extracted features was significantly reduced. In the classification, the highest accuracy rate of 95.4% was obtained using the support vector machine method. In the regression, the least squares support vector regression method obtained the best root mean square error (RMSE). The coefficient of determination (R2), RMSE, and relative standard deviation (RSD) between the predicted value of TVBN and the actual value were 0.963, 11.01, and 7.9%, respectively. The R2, RMSE, and RSD between the predicted value of AV and the actual value were 0.972, 0.170, and 6.05%, respectively. The LSTM feature extraction method provided a new method and reference for feature extraction using an E-nose to identify other animal-derived material samples.


Assuntos
Nariz Eletrônico , Produtos Pesqueiros , Semicondutores , Produtos Pesqueiros/análise , Animais , Algoritmos , Nitrogênio/análise , Metais/análise , Máquina de Vetores de Suporte , Óxidos/química , Peixes
3.
J Sci Food Agric ; 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38808632

RESUMO

BACKGROUND: The total volatile basic nitrogen (TVB-N) is the main indicator for evaluating the freshness of fish meal, and accurate detection and monitoring of TVB-N is of great significance for the health of animals and humans. Here, to realize fast and accurate identification of TVB-N, in this article, a self-developed electronic nose (e-nose) was used, and the mapping relationship between the gas sensor response characteristic information and TVB-N value was established to complete the freshness detection. RESULTS: The TVB-N variation curve was decomposed into seven subsequences with different frequency scales by means of variational mode decomposition (VMD). Each subsequence was modelled using different long short-term memory (LSTM) models, and finally, the final TVB-N prediction result was obtained by adding the prediction results based on different frequency components. To improve the performance of the LSTM, the sparrow search algorithm (SSA) was used to optimize the number of hidden units, learning rate and regularization coefficient of LSTM. The prediction results indicated that the high accuracy was obtained by the VMD-LSTM model optimized by SSA in predicting TVB-N. The coefficient of determination (R2), the root-mean-squared error (RMSE) and relative standard deviation (RSD) between the predicted value and the actual value of TVBN were 0.91, 0.115 and 6.39%, respectively. CONCLUSIONS: This method improves the performance of e-nose in detecting the freshness of fish meal and provides a reference for the quality detection of e-nose in other materials. © 2024 Society of Chemical Industry.

4.
Dev Cell ; 59(16): 2085-2100.e9, 2024 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-38821057

RESUMO

The interactions of environmental compartments with epithelial cells are essential for mammary gland development and homeostasis. Currently, the direct crosstalk between the endothelial niche and mammary epithelial cells remains poorly understood. Here, we show that faciogenital dysplasia 5 (FGD5) is enriched in mammary basal cells (BCs) and mediates critical interactions between basal and endothelial cells (ECs) in the mammary gland. Conditional deletion of Fgd5 reduced, whereas conditional knockin of Fgd5 increased, the engraftment and expansion of BCs, regulating ductal morphogenesis in the mammary gland. Mechanistically, murine mammary BC-expressed FGD5 inhibited the transcriptional activity of activating transcription factor 3 (ATF3), leading to subsequent transcriptional activation and secretion of CXCL14. Furthermore, activation of CXCL14/CXCR4/ERK signaling in primary murine mammary stromal ECs enhanced the expression of HIF-1α-regulated hedgehog ligands, which initiated a positive feedback loop to promote the function of BCs. Collectively, these findings identify functionally important interactions between BCs and the endothelial niche that occur through the FGD5/CXCL14/hedgehog axis.


Assuntos
Diferenciação Celular , Células Epiteliais , Glândulas Mamárias Animais , Animais , Camundongos , Feminino , Glândulas Mamárias Animais/metabolismo , Glândulas Mamárias Animais/citologia , Glândulas Mamárias Animais/crescimento & desenvolvimento , Células Epiteliais/metabolismo , Células Epiteliais/citologia , Quimiocinas CXC/metabolismo , Quimiocinas CXC/genética , Células Endoteliais/metabolismo , Células Endoteliais/citologia , Retroalimentação Fisiológica , Transdução de Sinais , Humanos , Proliferação de Células
5.
J Hazard Mater ; 467: 133672, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38325099

RESUMO

Trimethylamine (TMA), Dimethylamine (DMA), Ammonia (NH3) and formaldehyde (HCHO) are typical volatile gases and able to cause great damage to the environment and the human body, and they may appear along in some particular cases such as marine meat spoilage. However, gas sensors can detect all the 4 hazardous gases simultaneously have rarely been reported. In this study, a quartz crystal microbalance (QCM) gas sensor modified with La-Ce-MOF was employed for the detection of 4 target gases (TMA, DMA, NH3 and HCHO). The sensor exhibited excellent stability (63 days), selectivity (3.51 Hz/(µmoL/L) for TMA, 4.19 Hz/(µmoL/L) for DMA, 3.14·Hz/(µmoL/L) for NH3 and 3.08·Hz/(µmoL/L) for HCHO), robustness and sensitivity towards target gases detection. Vienna Ab-initio Simulation Package calculations showed that this superior sensing performance was attributed to the preferential adsorption of target gas molecules onto the nanomicrospheres via hydrogen bond. The adsorption energy was - 0.4329 eV for TMA, - 0.5204 eV for DMA, - 0.6823 eV for NH3 and - 0.7576 eV for HCHO, all of which are physically adsorbed. In the detection of hazardous gases, sensor surface active sites were often susceptible to environmental factors and interfering substances, leading to a decrease in the sensitivity of the gas sensor, which in turn affects the signal accuracy in practical applications. This issue has been effectively addressed and the sensor has been implemented for the assessment of the salmon meat freshness, which may contribute to further advancements in the development of QCM gas sensors for monitoring food quality, human beings health and environment safety.

6.
Polymers (Basel) ; 15(5)2023 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-36904391

RESUMO

Because of high conductivity, acceptable cost and good screen-printing process performance, silver pastes have been extensively used for making flexible electronics. However, there are few reported articles focusing on high heat resistance solidified silver pastes and their rheological properties. In this paper, a fluorinated polyamic acids (FPAA) is synthesized by polymerization of the 4,4'-(hexafluoroisopropylidene) diphthalic anhydride and 3,4'-diaminodiphenylether as monomers in the diethylene glycol monobutyl. The nano silver pastes are prepared by mixing the obtained FPAA resin with nano silver powder. The agglomerated particles caused by nano silver powder are divided and the dispersion of nano silver pastes are improved by three-roll grinding process with low roll gaps. The obtained nano silver pastes possess excellent thermal resistance with 5% weight loss temperature higher than 500 °C. The volume resistivity of cured nano silver paste achieves 4.52 × 10-7 Ω·m, when the silver content is 83% and the curing temperature is 300 °C. Additionally, the nano silver pastes have high thixotropic performance, which contributes to fabricate the fine pattern with high resolution. Finally, the conductive pattern with high resolution is prepared by printing silver nano pastes onto PI (Kapton-H) film. The excellent comprehensive properties, including good electrical conductivity, outstanding heat resistance and high thixotropy, make it a potential application in flexible electronics manufacturing, especially in high-temperature fields.

7.
Free Radic Biol Med ; 196: 53-64, 2023 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-36640852

RESUMO

Oxidative stress can attack precursor nucleotides, resulting in nucleic acid damage in cells. It remains unclear how 8-oxo-dGTP and 8-oxoGTP, oxidized forms of dGTP and GTP, respectively, could affect DNA or RNA oxidation levels and tumor development. To address this, we intravenously administered 8-oxo-dGTP and 8-oxoGTP to wild-type and MTH1-knockout mice. 8-oxoGTP administration increased frequency of tumor incidence, which is more prominent in MTH1-knockout mice. However, 8-oxo-dGTP treatment rather reduced tumor development regardless of the mouse genotype. The tumor suppressive effects of 8-oxo-dGTP were further confirmed using xenograft and C57/6J-ApcMin/Nju mouse models. Mechanistically, 8-oxo-dGTP increased the 8-oxo-dG contents in DNA and DNA strand breakage, induced cell cycle arrest in S phase and apoptosis mediated by AIF, eventually leading to reduced tumor incidence. These results suggest distinct roles of 8-oxo-dGTP and 8-oxoGTP in tumor development.


Assuntos
Neoplasias , Monoéster Fosfórico Hidrolases , Humanos , Animais , Camundongos , Monoéster Fosfórico Hidrolases/genética , Fase S , Nucleotídeos de Desoxiguanina/metabolismo , Neoplasias/genética , DNA/metabolismo , Camundongos Knockout , Apoptose , Enzimas Reparadoras do DNA/genética
8.
Microbiol Spectr ; 11(1): e0311322, 2023 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-36507658

RESUMO

Pleurotus ostreatus is usually cultivated in horticultural facilities that lack environmental control systems and often suffer heat stress (HS). Salicylic acid (SA) is recognized as a plant defense-related hormone. Here, SA treatment (200 µM) induced fungal resistance to HS of P. ostreatus, with decreased malondialdehyde (MDA) content and HSP expression. Further analysis showed that SA treatment in P. ostreatus increased the cytosolic trehalose content and reduced the intracellular reactive oxygen species (ROS) level. Moreover, H2O2 could restore the MDA content and HSP expression of P. ostreatus treated with SA under HS. In addition, trehalose (25 mM) or CaCl2 (5 mM) treatment induced fungal resistance to HS, and CaCl2 treatment increased the cytosolic trehalose content of P. ostreatus under HS. However, inhibiting Ca2+ levels using Ca2+ inhibitors or mutants reversed the trehalose content induced by SA in P. ostreatus under HS. In addition, inhibiting trehalose biosynthesis using Tps-silenced strains reversed the MDA content and HSP expression of P. ostreatus treated with SA under HS. Taken together, these results indicate that SA treatment alleviates the HS response of P. ostreatus by reducing the intracellular ROS level and increasing the cytosolic trehalose content. IMPORTANCE Heat stress (HS) is a crucial environmental challenge for edible fungi. Salicylic acid (SA), a plant defense-related hormone, plays key roles in plant responses to biotic and abiotic stresses. In this study, we found that SA treatment increased the cytosolic trehalose content and induced fungal resistance to HS in P. ostreatus. Further analysis showed that SA can alleviate the HS of P. ostreatus by reducing the intracellular ROS level and increasing the cytosolic trehalose content. Our results help to understand the mechanism underlying the responses of P. ostreatus to HS. In addition, this research provides new insights for the cultivation of P. ostreatus.


Assuntos
Pleurotus , Espécies Reativas de Oxigênio/metabolismo , Pleurotus/metabolismo , Trealose , Ácido Salicílico/metabolismo , Ácido Salicílico/farmacologia , Peróxido de Hidrogênio/metabolismo , Cloreto de Cálcio/metabolismo , Resposta ao Choque Térmico/fisiologia , Hormônios/metabolismo
9.
Sensors (Basel) ; 22(24)2022 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-36560307

RESUMO

This paper presents a straightforward method to develop a nanoporous graphene oxide (NGO)-functionalized quartz crystal microbalance (QCM) gas sensor for the detection of trimethylamine (TMA), aiming to form a reliable monitoring mechanism strategy for low-concentration TMA that can still cause serious odor nuisance. The synthesized NGO material was characterized by transmission electron microscopy, X-ray photoelectron spectroscopy, and Fourier transform infrared spectroscopy to verify its structure and morphology. Compared with the bare and GO-based QCM sensors, the NGO-based QCM sensor exhibited ultra-high sensitivity (65.23 Hz/µL), excellent linearity (R2 = 0.98), high response/recovery capability (3 s/20 s) and excellent repeatability (RSD = 0.02, n = 3) toward TMA with frequency shift and resistance. Furthermore, the selectivity of the proposed NGO-based sensor to TMA was verified by analysis of the dual-signal responses. It is also proved that increasing the conductivity did not improve the resistance signal. This work confirms that the proposed NGO-based sensor with dual signals provides a new avenue for TMA sensing, and the sensor is expected to become a potential candidate for gas detection.


Assuntos
Grafite , Nanoporos , Técnicas de Microbalança de Cristal de Quartzo , Grafite/química , Quartzo
10.
Nat Metab ; 4(9): 1202-1213, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36131205

RESUMO

Insulin signaling is essential for glucose metabolism, and insulin decreases insulin receptor (InsR) levels in a dose-dependent and time-dependent manner. However, the regulatory mechanisms of InsR reduction upon insulin stimulation remain poorly understood. Here, we show that Eph receptor B4 (EphB4), a tyrosine kinase receptor that modulates cell adhesion and migration, can bind directly to InsR, and this interaction is markedly enhanced by insulin. Due to the adaptor protein 2 (Ap2) complex binding motif in EphB4, the interaction of EphB4 and InsR facilitates clathrin-mediated InsR endocytosis and degradation in lysosomes. Hepatic overexpression of EphB4 decreases InsR and increases hepatic and systemic insulin resistance in chow-fed mice, whereas genetic or pharmacological inhibition of EphB4 improve insulin resistance and glucose intolerance in obese mice. These observations elucidate a role for EphB4 in insulin signaling, suggesting that EphB4 might represent a therapeutic target for the treatment of insulin resistance and type 2 diabetes.


Assuntos
Diabetes Mellitus Tipo 2 , Resistência à Insulina , Receptor EphB4 , Receptor de Insulina , Animais , Clatrina , Diabetes Mellitus Tipo 2/metabolismo , Glucose/metabolismo , Insulina/metabolismo , Resistência à Insulina/genética , Fígado/metabolismo , Camundongos , Receptor EphB4/metabolismo , Receptor de Insulina/metabolismo
11.
J Fungi (Basel) ; 8(9)2022 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-36135627

RESUMO

The global regulator LaeA plays crucial roles in morphological development and secondary metabolite biosynthesis in filamentous fungi. However, the functions of LaeA in basidiomycetes are less reported. The basidiomycete Pleurotus ostreatus is a well-known fungus used both in medicine and as food that produces polysaccharides and cellulolytic enzymes. In this study, we characterized three LaeA homologs (PoLaeA1, PoLaeA2, and PoLaeA3) in P. ostreatus. PoLaeA1 showed different expression patterns than PoLaeA2 and PoLaeA3 during different developmental stages. Silencing PoLaeA1 decreased the intracellular polysaccharide (IPS) content by approximately 28-30% and reduced intracellular ROS levels compared with those of the WT strain. However, silencing PoLaeA2 and PoLaeA3 decreased cellulase activity by 31-34% and 35-40%, respectively, and reduced the cytosolic Ca2+ content, compared with those of the WT strain. Further analysis showed that PoLaeA1 regulated IPS biosynthesis through intracellular ROS levels, whereas PoLaeA2 and PoLaeA3 regulated cellulase activity through intracellular Ca2+ signaling. Our results provide new insights into the regulation of polysaccharide biosynthesis and cellulase production in filamentous fungi.

12.
J Sci Food Agric ; 102(9): 3673-3682, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34890123

RESUMO

BACKGROUND: Milled rice are prone to be contaminated with spoilage or toxigenic fungi during storage, which may pose a real threat to human health. Most traditional methods require long periods of time for enumeration and quantification. However, headspace-gas chromatography-ion mobility spectrometry (HS-GC-IMS) technology could characterize the complex volatile organic compounds (VOCs) released from samples in a non-destructive and environmentally friendly manner. Thus, this study described an innovative HS-GC-IMS strategy for analyzing VOC profiles to detect fungal contamination in milled rice. RESULTS: A total of 24 typical target compounds were identified. Analysis of variance-partial least squares regression (APLSR) showed significant correlations between the target compounds and colony counts of fungi. While the changes of selected volatile components (acetic acid, 3-hydroxy-2-butanone and oct-en-3-ol) in fungi-inoculated rice had sufficiently high positive correlations with the colony counts, the logistic model could effectively be used to monitor the growth of individual fungus (R2  = 0.902-0.980). PLSR could effectively be used to predict fungal colony counts in rice samples (R2  = 0.831-0.953), and the different fungi-inoculated rice samples at 24 h could be successfully distinguished by support vector machine (SVM) (94.6%). The ability of HS-GC-IMS to monitor fungal infection would help to prevent contaminated rice grains from entering the food chain. CONCLUSIONS: This result indicated that HS-GC-IMS three-dimensional fingerprints may be appropriate for the early detection of fungal infection in rice grains. © 2021 Society of Chemical Industry.


Assuntos
Oryza , Compostos Orgânicos Voláteis , Cromatografia Gasosa-Espectrometria de Massas/métodos , Humanos , Espectrometria de Mobilidade Iônica/métodos , Análise dos Mínimos Quadrados , Oryza/microbiologia , Compostos Orgânicos Voláteis/química
13.
Appl Microbiol Biotechnol ; 105(19): 7353-7365, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34515845

RESUMO

The telomerase reverse transcriptase (TERT) is the core catalytic subunit of telomerase. Its canonical function is synthesizing telomeric repeats to maintain telomere length and chromosomal stability. Accumulating evidence suggests that TERT has other important fundamental functions in addition to its catalytic telomere repeat synthesis activity. However, the non-canonical roles of TERT independent of its enzymatic activity are not clear in filamentous fungi. In the present study, we characterized the GlTert gene in Ganoderma lucidum. The non-canonical roles of GlTert were explored using GlTert-silenced strains (Terti8 and Terti25) obtained by RNA interference. Silencing GlTert delayed the fungal growth, decreased the length between hyphal branches, and induced fungal resistance to oxidative stress in G. ludicum. Further examination revealed that the intracellular ROS (reactive oxygen species) levels were increased while the enzyme activities of the antioxidant systems (superoxide dismutase, catalase, glutathione peroxidase, and ascorbate peroxidase) were decreased in GlTert-silenced strains. In addition, silencing GlTert decreased the ganoderic acid (GA) biosynthesis of G. lucidum. Taken together, our results indicate that GlTert plays a fundamental function on fungal growth, oxidative stress, and GA biosynthesis in G. lucidum, providing new insights for the canonical functions of TERT in filamentous fungi. KEY POINTS: • GlTert affected fungal growth and hyphal branching of G. lucidum. • Silencing GlTert increased the intracellular ROS levels of G. lucidum. • GlTert regulated GA biosynthesis of G. lucidum.


Assuntos
Reishi , Telomerase , Estresse Oxidativo , Telomerase/genética , Triterpenos
14.
Anal Bioanal Chem ; 413(23): 5789-5798, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34322736

RESUMO

In recent years, the invasive cypress bark beetle (Phloeosinus aubei) has caused extensive damage to Platycladus orientalis plants in China, but its infestation is hard to monitor in the early stages. In this study, gas chromatography-mass spectrometry (GC-MS) was initially employed to investigate the volatile organic compound (VOC) emissions of P. aubei-infested P. orientalis saplings. The emissions of total sesquiterpenes were dominating (84-86% of total VOCs) and increased by 3.09-fold in P. aubei-damaged P. orientalis samples compared to undamaged samples, and the monoterpenes, aromatic compounds, and ketone emissions also had varying degrees of increase between 1.39-fold and 5.65-fold. Based on this variation, gas chromatography-ion mobility spectrometry (GC-IMS) was applied, as an untargeted analytical approach, to discriminate P. orientalis samples with different invasive severity. Two different features derived from GC-IMS data were adopted as the input information for classification and prediction models. Results showed that grid search support vector machine (GS-SVM) combined with multilinear principal component analysis (MPCA) based on spectral fingerprint achieved the best classification performances (> 88.98%), and partial least squares discriminant analysis (PLSR) method can accurately predict the pest numbers (R2 > 0.9423 and RMSE < 0.9827). In a word, the VOC profiling-based approach had the potential for evaluating P. aubei invasive severity and pest management.


Assuntos
Besouros/efeitos dos fármacos , Cupressaceae/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Espécies Introduzidas , Controle de Pragas/métodos , Compostos Orgânicos Voláteis/farmacologia , Animais , China
15.
Sci Transl Med ; 13(586)2021 03 24.
Artigo em Inglês | MEDLINE | ID: mdl-33762435

RESUMO

Most basal-like breast cancers (BLBCs) are triple-negative breast cancers (TNBCs), which have the worst prognosis and distant metastasis-free survival among breast cancer subtypes. Now, no targeted therapies are available for patients with BLBC due to the lack of reliable and effective molecular targets. Here, we performed the BLBC tissue microarray-based immunohistochemical analysis and showed that Faciogenital Dysplasia 5 (FGD5) abundance is associated with poor prognosis in BLBCs. FGD5 deletion decreased the proliferation, invasion, and tumorsphere formation capacity of BLBC cells. Furthermore, genetic inhibition of Fgd5 in mouse mammary epithelial cells attenuated BLBC initiation and progression by reducing the self-renewal ability of tumor-initiating cells. In addition, FGD5 abundance was positively correlated with the abundance of epidermal growth factor receptor (EGFR) in BLBCs. FGD5 ablation decreased EGFR abundance by reducing EGFR stability in TNBC cells in 2D and 3D culture conditions. Mechanistically, FGD5 binds to EGFR and interferes with basal EGFR ubiquitination and degradation induced by the E3 ligase ITCH. Impaired EGFR degradation caused BLBC cell proliferation and promoted invasive properties and self-renewal. To verify the role of the FGD5-EGFR interaction in the regulation of EGFR stability, we screened a cell-penetrating α-helical peptide PER3 binding with FGD5 to disrupt the interaction. Treatment of BLBC patient-derived xenograft-bearing mice with the peptide PER3 disrupting the FGD5-EGFR interaction either with or without chemotherapy reduced BLBC progression. Our study identified FGD5 as a positive modulator of tumor-initiating cells and suggests a potential therapeutic option for the BLBC subtype of breast cancer.


Assuntos
Fatores de Troca do Nucleotídeo Guanina/genética , Células-Tronco Neoplásicas , Neoplasias de Mama Triplo Negativas , Animais , Receptores ErbB , Feminino , Humanos , Camundongos , Neoplasias de Mama Triplo Negativas/genética
16.
J Sci Food Agric ; 101(10): 4220-4228, 2021 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-33426692

RESUMO

BACKGROUND: Rice grains can be contaminated easily by certain fungi during storage and in the market chain, thus generating a risk for humans. Most classical methods for identifying and rectifying this problem are complex and time-consuming for manufacturers and consumers. However, E-nose technology provides analytical information in a non-destructive and environmentally friendly manner. Two-feature fusion data combined with chemometrics were employed for the determination of Aspergillus spp. contamination in milled rice. RESULTS: Linear discriminant analysis (LDA) indicated that the efficiency of fusion signals ('80th s values' and 'area values') outperformed that of independent E-nose signals. Linear discriminant analysis showed clear discrimination of fungal species in stored milled rice for four groups on day 2, and the discrimination accuracy reached 92.86% by using an extreme learning machine (ELM). Gas chromatography-mass spectrometry (GC-MS) analysis showed that the volatile compounds had close relationships with fungal species in rice. The quantification results of colony counts in milled rice showed that the monitoring models based on ELM and the genetic algorithm optimized support vector machine (GA-SVM) (R2  = 0.924-0.983) achieved better performances than those based on partial least squares regression (PLSR) (R2  = 0.877-0.913). The ability of the E-nose to monitor fungal infection at an early stage would help to prevent contaminated rice grains from entering the food chains. CONCLUSIONS: The results indicated that an E-nose coupled with ELM or GA-SVM algorithm could be a useful tool for the rapid detection of fungal infection in milled rice, to prevent contaminated rice from entering the food chain. © 2021 Society of Chemical Industry.


Assuntos
Aspergillus/isolamento & purificação , Nariz Eletrônico , Contaminação de Alimentos/análise , Oryza/química , Oryza/microbiologia , Preparações de Plantas/química , Aspergillus/química , Análise Discriminante , Cromatografia Gasosa-Espectrometria de Massas , Pós/química , Máquina de Vetores de Suporte
17.
J Agric Food Chem ; 68(45): 12719-12728, 2020 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-33124819

RESUMO

Conventional methods for detecting fungal contamination are generally time-consuming and sample-destructive, making them impossible for large-scale nondestructive detection and real-time analysis. Therefore, the potential of headspace-gas chromatography-ion mobility spectrometry (HS-GC-IMS) was examined for the rapid determination of fungal infection on wheat samples in a rapid and nondestructive manner. In addition, the validation experiment of detecting the percent A. flavus infection presented in simulated field samples was carried out. Because the dual separation of HS-GC-IMS could generate massive amounts of three-dimensional data, proper chemometric processing was required. In this study, two chemometric strategies including: (i) nontargeted spectral fingerprinting and (ii) targeted specific markers were introduced to evaluate the performances of classification and prediction models. Results showed that satisfying results for the differentiation of fungal species were obtained based on both strategies (>80%) by the genetic algorithm optimized support vector machine (GA-SVM), and better values were obtained based on the first strategy (100%). Likewise, the GA-SVM model based on the first strategy achieved the best prediction performances (R2 = 0.979-0.998) of colony counts in fungal infected samples. The results of validation experiment showed that GA-SVM models based on the first strategy could still provide satisfactory classification (86.67%) and prediction (R2 = 0.889) performances for percent A. flavus infection presented in simulated field samples at day 4. This study indicated the feasibility of HS-GC-IMS-based approaches for the early detection of fungal contamination in wheat kernels.


Assuntos
Aspergillus/isolamento & purificação , Contaminação de Alimentos/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Penicillium/isolamento & purificação , Triticum/microbiologia , Aspergillus/crescimento & desenvolvimento , Penicillium/crescimento & desenvolvimento , Triticum/química
18.
Nat Commun ; 10(1): 5720, 2019 12 16.
Artigo em Inglês | MEDLINE | ID: mdl-31844113

RESUMO

The existence of breast cancer stem cells (BCSCs) is a major reason underlying cancer metastasis and recurrence after chemotherapy and radiotherapy. Targeting BCSCs may ameliorate breast cancer relapse and therapy resistance. Here we report that expression of the pseudokinase Tribble 3 (TRIB3) positively associates with breast cancer stemness and progression. Elevated TRIB3 expression supports BCSCs by interacting with AKT to interfere with the FOXO1-AKT interaction and suppress FOXO1 phosphorylation, ubiquitination, and degradation by E3 ligases SKP2 and NEDD4L. The accumulated FOXO1 promotes transcriptional expression of SOX2, a transcriptional factor for cancer stemness, which in turn, activates FOXO1 transcription and forms a positive regulatory loop. Disturbing the TRIB3-AKT interaction suppresses BCSCs by accelerating FOXO1 degradation and reducing SOX2 expression in mouse models of breast cancer. Our study provides insights into breast cancer development and confers a potential therapeutic strategy against TRIB3-overexpressed breast cancer.


Assuntos
Neoplasias da Mama/genética , Proteínas de Ciclo Celular/metabolismo , Proteína Forkhead Box O1/metabolismo , Células-Tronco Neoplásicas/patologia , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Repressoras/metabolismo , Fatores de Transcrição SOXB1/genética , Animais , Mama/patologia , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Progressão da Doença , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Camundongos , Pessoa de Meia-Idade , Ligação Proteica , Proteínas Serina-Treonina Quinases/metabolismo , Proteólise , Proteínas Proto-Oncogênicas c-akt/metabolismo , Análise Serial de Tecidos , Transcrição Gênica , Ensaios Antitumorais Modelo de Xenoenxerto
19.
Free Radic Res ; 52(9): 961-969, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30422023

RESUMO

Emerging evidence suggests that microbial pathogens may induce oxidative stress in infected hosts. The aim of the present study was to investigate the relationship between changes in oxidative stress and intestinal infection with and without antibiotic treatment in animal models. Sprague-Dawley (SD) rats were divided into three groups: rats infected with Salmonella enterica serovar Enteritidis (S. enteritidis), rats infected with S. enteritidis followed by norfloxacin treatment, and the control group. To evaluate oxidative stress changes, levels of 8-oxo-7,8-dihydroguanosine (8-oxo-Gsn) and 8-oxo-7,8-dihydro-2-deoxyguanosine (8-oxo-dGsn), which represented oxidative damage to RNA and DNA, respectively, were analysed in urine and tissue samples. In urine, the level of 8-oxo-Gsn increased significantly after oral exposure to S. enteritidis (p ≤ 0.001) and returned to baseline after recovery. Notably, norfloxacin treatment decreased the level of 8-oxo-Gsn in urine significantly (p = 0.001). Changes of 8-oxo-Gsn measured in tissues from the small intestine, colon, liver and spleen were consistent with 8-oxo-Gsn measured in urine. Our study suggested that 8-oxo-Gsn in urine may serve as a highly sensitive biomarker for evaluating the severity of S. enteritidis infection and the effectiveness of antibiotic treatment against infection.


Assuntos
Dano ao DNA/efeitos dos fármacos , Infecções/genética , Fígado/metabolismo , Estresse Oxidativo , Animais , Dano ao DNA/genética , Humanos , Infecções/microbiologia , Infecções/patologia , Mucosa Intestinal/microbiologia , Mucosa Intestinal/patologia , Fígado/microbiologia , Fígado/patologia , Oxirredução , Valor Preditivo dos Testes , RNA/química , Ratos , Salmonella enteritidis/patogenicidade
20.
FASEB J ; 31(6): 2533-2547, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28242773

RESUMO

Recent studies have shown that KIF5B (conventional kinesin heavy chain) mediates glucose transporter type 4 translocation and adiponectin secretion in 3T3-L1 adipocytes, suggesting an involvement of KIF5B in the homeostasis of metabolism. However, the in vivo physiologic function of KIF5B in adipose tissue remains to be determined. In this study, adipose-specific Kif5b knockout (F-K5bKO) mice were generated using the Cre-LoxP strategy. F-K5bKO mice had similar body weights to controls fed on a standard chow diet. However, F-K5bKO mice had hyperlipidemia and significant glucose intolerance and insulin resistance. Deletion of Kif5b aggravated the deleterious impact of a high-fat diet (HFD) on body weight gain, hepatosteatosis, glucose tolerance, and systematic insulin sensitivity. These changes were accompanied by impaired insulin signaling, decreased secretion of adiponectin, and increased serum levels of leptin and proinflammatory adipokines. F-K5bKO mice fed on an HFD exhibited lower energy expenditure and thermogenic dysfunction as a result of whitening of brown adipose due to decreased mitochondria biogenesis and down-regulation of key thermogenic gene expression. In conclusion, selective deletion of Kif5b in adipose tissue exacerbates HFD-induced obesity and its associated metabolic disorders, partly through a decrease in energy expenditure, dysregulation of adipokine secretion, and insulin signaling.-Cui, J., Pang, J., Lin, Y.-J., Gong, H., Wang, Z.-H., Li, Y.-X., Li, J., Wang, Z., Jiang, P., Dai, D.-P., Li, J., Cai, J.-P., Huang, J.-D., Zhang, T.-M. Adipose-specific deletion of Kif5b exacerbates obesity and insulin resistance in a mouse model of diet-induced obesity.


Assuntos
Tecido Adiposo/metabolismo , Dieta Hiperlipídica/efeitos adversos , Resistência à Insulina/fisiologia , Cinesinas/metabolismo , Obesidade/induzido quimicamente , Animais , Intolerância à Glucose , Resistência à Insulina/genética , Cinesinas/genética , Masculino , Camundongos , Camundongos Knockout
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