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1.
Heliyon ; 9(10): e20522, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37790976

RESUMO

This study introduces a novel machine learning methodology for predicting GlutoPeak test parameters from image data, leveraging AutoKeras and transfer learning. The GlutoPeak test is a tool used in the baking industry to evaluate the properties of flour, based on its gluten strength and elasticity. Our research aimed to devise an efficient and cost-effective technique for quantifying the gluten properties of wheat varieties. We aimed to accomplish this by predicting the GlutoPeak test results with convolutional neural network (CNN) models, utilizing the benefits of transfer learning and AutoKeras. AutoKeras is a public code repository capable of automating neural architecture search and hyperparameter tuning. The ResNet101 model, when trained with the Adam optimizer, achieved the highest accuracy of 0.5765 in the 2-class prediction. Meanwhile, the ResNet101 model trained with the SGD optimizer reached the highest accuracy of 0.4362 in the 4-class prediction. The outcomes of this study illustrate the possibility in using machine learning and deep learning techniques for predicting GlutoPeak test parameters from image data. This offers a faster and more cost-effective approach for evaluating gluten quality in wheat varieties.

2.
Food Chem ; 421: 136182, 2023 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-37086517

RESUMO

Proanthocyanidins (PA) form poorly digestible complexes with starch. The study examined amylase degradation mechanism and hydrothermal stability of starch-PA complexes. Sorghum-derived PA was complexed with wheat starch, reconstituted into flour (10% gluten added) and processed into crackers and pancakes. In vitro digestion profile of the complexes and products were characterized. The starch-PA complexes retained more (34-84%) fragments with degree of polymerization (DP) > 6,000 after 120 min digestion than controls (0-21%). Debranching further revealed higher retention of DP 11 - 30 chains in the digested starch-PA complexes than controls, suggesting amylopectin complexation contributed to reduced starch digestion. Starch-PA complexes retained reduced digestibility (50-56% higher resistant starch vs controls) in the cracker, but not pancake model. However, removing gluten from the pancake formulation restored the reduced digestibility of the starch-PA complexes. The starch-PA complexes are stable to hydrothermal processing, but can be disrupted by hydrophobic gluten proteins under excess moisture conditions.


Assuntos
Proantocianidinas , Amido , Amido/química , Amilases , Amilose/química , Glutens , Digestão
3.
Curr Res Food Sci ; 5: 1668-1675, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36193040

RESUMO

High amylose and waxy starches from maize and potato were incubated with plasma-activated water (PAW) at 25 °C, 60 °C, and 80 °C temperatures to investigate PAW treatment effects on the starches' properties. At 60 °C incubation temperature, the starches were basically annealed with PAW. Annealing starches with PAW significantly increased (p < 0.05) the gelatinization parameters except for the enthalpy of gelatinization of waxy potato starch. Furthermore, starch swelling power significantly decreased while the water absorption capacity and solubility increased significantly when incubated at 80 °C. X-ray photoelectron spectroscopy (XPS) analysis showed the oxidation of C-C/C-H and C-O into carboxyl groups in waxy and high amylose maize starches incubated with PAW at 60 °C and 80 °C, respectively. In addition, cross-linking was observed in waxy maize and high amylose potato incubated with PAW at 80 °C and 25 °C, respectively. Overall, the results indicated PAW temperature is an important factor in modifying cereals and tuber starches with PAW.

4.
Mol Cancer Res ; 20(12): 1799-1810, 2022 12 02.
Artigo em Inglês | MEDLINE | ID: mdl-36074101

RESUMO

The TP53 gene is mutated in 80% of triple-negative breast cancers. Cells that harbor the hot-spot p53 gene mutation R273H produce an oncogenic mutant p53 (mtp53) that enhances cell proliferative and metastatic properties. The enhanced activities of mtp53 are collectively referred to as gain-of-function (GOF), and may include transcription-independent chromatin-based activities shared with wild-type p53 (wtp53) such as association with replicating DNA and DNA replication associated proteins like PARP1. However, how mtp53 upregulates cell proliferation is not well understood. wtp53 interacts with PARP1 using a portion of its C-terminus. The wtp53 oligomerization and far C-terminal domain (CTD) located within the C-terminus constitute putative GOF-associated domains, because mtp53 R273H expressing breast cancer cells lacking both domains manifest slow proliferation phenotypes. We addressed if the C-terminal region of mtp53 R273H is important for chromatin interaction and breast cancer cell proliferation using CRISPR-Cas9 mutated MDA-MB-468 cells endogenously expressing mtp53 R273H C-terminal deleted isoforms (R273HΔ381-388 and R273HΔ347-393). The mtp53 R273HΔ347-393 lacks the CTD and a portion of the oligomerization domain. We observed that cells harboring mtp53 R273HΔ347-393 (compared with mtp53 R273H full-length) manifest a significant reduction in chromatin, PARP1, poly-ADP-ribose (PAR), and replicating DNA binding. These cells also exhibited impaired response to hydroxyurea replicative stress, decreased sensitivity to the PARP-trapping drug combination temozolomide-talazoparib, and increased phosphorylated 53BP1 foci, suggesting reduced Okazaki fragment processing. IMPLICATIONS: The C-terminal region of mtp53 confers GOF activity that mediates mtp53-PARP1 and PAR interactions assisting DNA replication, thus implicating new biomarkers for PARP inhibitor therapy.


Assuntos
Poli Adenosina Difosfato Ribose , Proteína Supressora de Tumor p53 , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Genes p53 , Mutação com Ganho de Função , Poli(ADP-Ribose) Polimerase-1 , Cromatina
5.
J Food Sci ; 87(8): 3496-3512, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35781707

RESUMO

In this study, the effects of extrusion conditions such as feed moisture content (20%, 24%, and 28%), screw speed (200, 300, and 400 rpm), and extrusion temperature (130, 150, and 170°C) on the physical and functional properties (moisture content, expansion ratio, bulk density, hardness, water absorption index [WAI], water solubility index [WSI]) of intermediate wheatgrass (IWG) were investigated for the first time. Response surface methodology was used to model and optimize the extrusion conditions to produce expanded IWG. The model coefficient of determination (R2 ) was high for all the responses (0.87-0.98). All the models were found to be significant (p < 0.05) and were validated with independent experiments. Generally, all the extrusion conditions were found to have significant effects on the IWG properties measured. Increasing the screw speed and decreasing the extrusion temperature resulted in IWG extrudates with a high expansion ratio. This also resulted in IWG extrudates with generally low hardness and bulk density. Screw speed was found to have the most significant effect on the WAI and WSI, with increasing screw speed resulting in a significant (p < 0.05) decrease in WAI and a significant (p < 0.05) increase in WSI. The optimum conditions for obtaining an IWG extrudate with a high expansion ratio and WAI were found to be 20% feed moisture, 200 -356 rpm screw speed, and 130-154°C extrusion temperature. PRACTICAL APPLICATION: Extrusion cooking was employed in the production of expanded IWG. This research could provide a foundation to produce expanded IWG, which can potentially be used as breakfast cereals and snacks. This is critical in the efforts to commercialize IWG for mainstream food applications.


Assuntos
Culinária , Manipulação de Alimentos , Fenômenos Químicos , Culinária/métodos , Manipulação de Alimentos/métodos , Poaceae , Solubilidade , Água
6.
Curr Res Food Sci ; 5: 451-463, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35243357

RESUMO

Native starches have limited applications in the food industry due to their unreactive and insoluble nature. Cold plasma technology, including plasma-activated water (PAW), has been explored to modify starches to enhance their functional, thermal, molecular, morphological, and physicochemical properties. Atmospheric cold plasma and low-pressure plasma systems have been used to alter starches and have proven successful. This review provides an in-depth analysis of the different cold plasma setups employed for starch modifications. The effect of cold plasma technology application on starch characteristics is summarized. We also discussed the potential of plasma-activated water as a novel alternative for starch modification. This review provides information needed for the industrial scale-up of cold plasma technologies as an eco-friendly method of starch modification.

7.
J Food Sci ; 87(2): 686-698, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35067922

RESUMO

The effect of carbon dioxide-argon radio frequency cold plasma treatment on the in vitro digestion and structural characteristics of granular and non-granular waxy maize, potato, and rice starches was investigated in this study. The effect on the fine structure of waxy potato was very minimal after plasma treatment irrespective of their granular or non-granular form. The short chain length (SCL) of waxy maize and rice (granular and non-granular) starches was reduced leading to subsequent increases in the long chain length (LCL). In vitro digestibility studies showed that cold plasma treatment enhanced (p < 0.05) the amount of slowly digestible starches (5.62%; 10.24%) and resistant starches (0.28%; 85.66%) in non-granular waxy maize (WMS NG) and granular waxy potato starches (WPS G), respectively. The amount of rapidly digestible starches increased in granular waxy maize starch (WMS G) (85.08%) but was unaffected in non-granular waxy rice (WRS NG), WPS G, and non-granular waxy potato starches after plasma treatment. FTIR-ATR data confirmed the ability of cold plasma to induce cross-linking in waxy starches specifically in WMS NG, WRS G, WRS NG, and WPS G. Overall, the unit and internal chain structure of the waxy starches were mostly unaffected by radio frequency plasma treatment. Cross-linking served as the dominant mechanism by which plasma altered the structure and digestibility of these starches. PRACTICAL APPLICATION: Cold plasma technology has been suggested as a green technique for starch modification. More research is, however, needed to facilitate the industrial scale up of this technology. In this study, we utilized a carbon dioxide-argon radio frequency cold plasma to modify waxy maize, rice and potato starches. Cold plasma treatment resulted in starches that were resistant to digestion and were highly cross-linked. The cross-linking would give the starches the ability to possibly withstand the high temperatures and shear that can be applied during industrial processing.


Assuntos
Gases em Plasma , Amilopectina , Hidrólise , Amido , Ceras , Zea mays
8.
Food Chem ; 371: 131135, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-34571408

RESUMO

The impact of plasma-produced reactive oxygen and nitrogen species, in particular O3, NxOy, H2O2 and OH, on the structure and functionality of pea protein isolate (PPI) was evaluated. Reactive species were produced through a combination of controlled measurements and plasma treatments. Pronounced structural and functional effects were observed upon treatment with reactive species at pH 2. All reactive species induced protein denaturation and the formation of disulfide-linked soluble aggregates. A significant increase in surface hydrophobicity and ß-sheet content was only induced by treatment with O3 and OH. These specific changes resulted in significant enhancement in gelation and emulsification. While H2O2 enhanced PPI color by increasing whiteness, it had the least impact on protein structure and functionality. Results of this work can be used to optimize cold atmospheric plasma treatment of PPI to induce specific structural changes and a directed enhancement in functionality.


Assuntos
Proteínas de Ervilha , Gases em Plasma , Peróxido de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Espécies Reativas de Oxigênio
9.
Front Cell Dev Biol ; 9: 772315, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34881245

RESUMO

The TP53 gene is often mutated in cancer, with missense mutations found in the central DNA binding domain, and less often in the C-terminal oligomerization domain (OD). These types of mutations are found in patients with the rare inherited cancer predisposition disorder called Li-Fraumeni syndrome. We previously found that mutant p53 (mtp53) R273H associates with replicating DNA and promotes the chromatin association of replication-associated proteins mini-chromosome maintenance 2 (MCM2), and poly ADP-ribose polymerase 1(PARP1). Herein, we created dual mutants in order to test if the oligomerization state of mtp53 R273H played a role in chromatin binding oncogenic gain-of-function (GOF) activities. We used site-directed mutagenesis to introduce point mutations in the OD in wild-type p53 (wtp53), and mtp53 R273H expressing plasmids. The glutaraldehyde crosslinking assay revealed that both wtp53 and mtp53 R273H formed predominantly tetramers, while the single OD mutant A347D, and the dual mtp53 R273H-A347D, formed predominantly dimers. The R337C, L344P, mtp53 R273H-R337C, and mtp53 R273H-L344P proteins formed predominantly monomers. Wtp53 was able to activate the cyclin-dependent kinase gene p21/waf and the p53 feedback regulator MDM2. As expected, the transactivation activity was lost for all the single mutants, as well as the mtp53 R273H-dual mutants. Importantly, mtp53 R273H and the dual oligomerization mutants, R273H-A347D, R273H-R337C, and R273H-L344P were able to interact with chromatin. Additionally, the dual oligomerization mutants, R273H-A347D, R273H-R337C, and R273H-L344P, maintained strong interactions with MCM2 and PARP1. Our findings suggest that while mtp53 R273H can form tetramers, tetramer formation is not required for the GOF associated chromatin interactions.

10.
Theor Appl Genet ; 134(11): 3743-3757, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34345971

RESUMO

KEY MESSAGE: Moisture content during nixtamalization can be accurately predicted from NIR spectroscopy when coupled with a support vector machine (SVM) model, is strongly modulated by the environment, and has a complex genetic architecture. Lack of high-throughput phenotyping systems for determining moisture content during the maize nixtamalization cooking process has led to difficulty in breeding for this trait. This study provides a high-throughput, quantitative measure of kernel moisture content during nixtamalization based on NIR scanning of uncooked maize kernels. Machine learning was utilized to develop models based on the combination of NIR spectra and moisture content determined from a scaled-down benchtop cook method. A linear support vector machine (SVM) model with a Spearman's rank correlation coefficient of 0.852 between wet laboratory and predicted values was developed from 100 diverse temperate genotypes grown in replicate across two environments. This model was applied to NIR spectra data from 501 diverse temperate genotypes grown in replicate in five environments. Analysis of variance revealed environment explained the highest percent of the variation (51.5%), followed by genotype (15.6%) and genotype-by-environment interaction (11.2%). A genome-wide association study identified 26 significant loci across five environments that explained between 5.04% and 16.01% (average = 10.41%). However, genome-wide markers explained 10.54% to 45.99% (average = 31.68%) of the variation, indicating the genetic architecture of this trait is likely complex and controlled by many loci of small effect. This study provides a high-throughput method to evaluate moisture content during nixtamalization that is feasible at the scale of a breeding program and provides important information about the factors contributing to variation of this trait for breeders and food companies to make future strategies to improve this important processing trait.


Assuntos
Culinária/métodos , Aprendizado de Máquina , Espectroscopia de Luz Próxima ao Infravermelho , Água/análise , Estudos de Associação Genética , Genótipo , Zea mays/genética
11.
Foods ; 10(7)2021 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-34202754

RESUMO

Previous work indicated that bran removal promotes network formation in breads prepared from intermediate wheatgrass (IWG) flour. However, refinement reduces yields as well as contents of nutritionally beneficial compounds such as fiber. This study evaluated xylanase pretreatment of IWG bran as a processing option to enhance the properties of bread made with half of the original bran content. Xylanase pretreatment did not affect stickiness but significantly reduced hardness and increased specific loaf volumes compared to negative (without xylanase) and positive controls (with xylanase but without pretreatment). However, the surface of breads with pretreated bran was uneven due to structural collapse during baking. Fewer but larger gas cells were present due to pretreatment. Addition of ascorbic acid modulated these effects, but did not prevent uneven surfaces. Accessible thiol concentrations were slightly but significantly increased by xylanase pretreatment, possibly due to a less compact crumb structure. Endogenous xylanases (apparent activity 0.46 and 5.81 XU/g in flour and bran, respectively) may have been activated during the pretreatment. Moreover, Triticum aestivum xylanase inhibitor activity was also detected (193 and 410 InU/g in flour and bran). Overall, xylanase pretreatment facilitates incorporation of IWG bran into breads, but more research is needed to improve bread appearance.

13.
Oncotarget ; 12(12): 1128-1146, 2021 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-34136083

RESUMO

We recently documented that gain-of-function (GOF) mutant p53 (mtp53) R273H in triple negative breast cancer (TNBC) cells interacts with replicating DNA and PARP1. The missense R273H GOF mtp53 has a mutated central DNA binding domain that renders it unable to bind specifically to DNA, but maintains the capacity to interact tightly with chromatin. Both the C-terminal domain (CTD) and oligomerization domain (OD) of GOF mtp53 proteins are intact and it is unclear whether these regions of mtp53 are responsible for chromatin-based DNA replication activities. We generated MDA-MB-468 cells with CRISPR-Cas9 edited versions of the CTD and OD regions of mtp53 R273H. These included a frame-shift mtp53 R273Hfs387, which depleted mtp53 protein expression; mtp53 R273HΔ381-388, which had a small deletion within the CTD; and mtp53 R273HΔ347-393, which had both the OD and CTD regions truncated. The mtp53 R273HΔ347-393 existed exclusively as monomers and disrupted the chromatin interaction of mtp53 R273H. The CRISPR variants proliferated more slowly than the parental cells and mt53 R273Hfs387 showed the most extreme phenotype. We uncovered that after thymidine-induced G1/S synchronization, but not hydroxyurea or aphidicholin, R273Hfs387 cells displayed impairment of S-phase progression while both R273HΔ347-393 and R273HΔ381-388 displayed only moderate impairment. Moreover, reduced chromatin interaction of MCM2 and PCNA in mtp53 depleted R273Hfs387 cells post thymidine-synchronization revealed delayed kinetics of replisome assembly underscoring the slow S-phase progression. Taken together our findings show that the CTD and OD domains of mtp53 R273H play critical roles in mutant p53 GOF that pertain to processes associated with DNA replication.

14.
Biomech Model Mechanobiol ; 20(1): 69-91, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32860537

RESUMO

An essential prerequisite for the efficient biomechanical tailoring of crops is to accurately relate mechanical behavior to compositional and morphological properties across different length scales. In this article, we develop a multiscale approach to predict macroscale stiffness and strength properties of crop stem materials from their hierarchical microstructure. We first discuss the experimental multiscale characterization based on microimaging (micro-CT, light microscopy, transmission electron microscopy) and chemical analysis, with a particular focus on oat stems. We then derive in detail a general micromechanics-based model of macroscale stiffness and strength. We specify our model for oats and validate it against a series of bending experiments that we conducted with oat stem samples. In the context of biomechanical tailoring, we demonstrate that our model can predict the effects of genetic modifications of microscale composition and morphology on macroscale mechanical properties of thale cress that is available in the literature.


Assuntos
Produtos Agrícolas/fisiologia , Modelos Biológicos , Caules de Planta/fisiologia , Biomassa , Fenômenos Biomecânicos , Parede Celular/genética , Produtos Agrícolas/ultraestrutura , Elasticidade , Mutação/genética , Caules de Planta/ultraestrutura , Microtomografia por Raio-X
15.
Mol Pharm ; 18(1): 338-346, 2021 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-33289569

RESUMO

Triple negative breast cancer (TNBC) has no targeted detection or treatment method. Mutant p53 (mtp53) is overexpressed in >80% of TNBCs, and the stability of mtp53 compared to the instability of wild-type p53 (wtp53) in normal cells makes mtp53 a promising TNBC target for diagnostic and theranostic imaging. We generated Cy5p53Tet, a novel nucleus-penetrating mtp53-oligomerization-domain peptide (mtp53ODP) to the tetramerization domain (TD) of mtp53. This mtp53ODP contains the p53 TD sequence conjugated to a Cy5 fluorophore for near-infrared fluorescence imaging (NIRF). In vitro co-immunoprecipitation and glutaraldehyde cross-linking showed a direct interaction between mtp53 and Cy5p53Tet. Confocal microscopy and flow cytometry demonstrated higher uptake of Cy5p53Tet in the nuclei of TNBC MDA-MB-468 cells with mtp53 R273H than in ER-positive MCF7 cells with wtp53. Furthermore, depletion of mtp53 R273H caused a decrease in the uptake of Cy5p53Tet in nuclei. In vivo analysis of the peptide in mice bearing MDA-MB-468 xenografts showed that Cy5p53Tet could be detected in tumor tissue 12 min after injection. In these in vivo experiments, significantly higher uptake of Cy5p53Tet was observed in mtp53-expressing MDA-MB-468 xenografts compared with the wtp53-expressing MCF7 tumors. Cy5p53Tet has clinical potential as an intraoperative imaging agent for fluorescence-guided surgery, and the mtp53ODP scaffold shows promise for modification in the future to enable the delivery of a wide variety of payloads including radionuclides and toxins to mtp53-expressing TNBC tumors.


Assuntos
Antineoplásicos/farmacologia , Núcleo Celular/efeitos dos fármacos , Peptídeos/farmacologia , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Proteína Supressora de Tumor p53/metabolismo , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Feminino , Humanos , Células MCF-7 , Camundongos , Camundongos Nus , Mutação/efeitos dos fármacos , Neoplasias de Mama Triplo Negativas/metabolismo
16.
J Agric Food Chem ; 68(45): 12569-12576, 2020 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-33126793

RESUMO

Understanding the contribution of stem cell wall components to lodging is important in developing breeding programs aimed at reducing lodging in cereal crops. This study is one of the first to investigate the correlation between the amounts of cell wall-bound ferulic acid, p-coumaric acid, and lignin in the nodes and internodes of cereals (oat, wheat, and barley) and their lodging susceptibility during grain fill. All samples, except two-row barley, were susceptible to lodging and expressed a significantly lower stalk strength. Lignin and phenolic contents between nodes and internodes of all samples were significantly different, with internodes having higher amounts (5.5-7.0 and 10.9-16.2 µg/g p-coumaric acid, and 2.5-3.2 and 3.9-7.1 µg/g ferulic acid in nodes and internodes, respectively). The acid-soluble lignin content was different between nodes and internodes but not between crops. This data set did not correlate with lodging classification, possibly due to sample size and type.


Assuntos
Avena/metabolismo , Parede Celular/metabolismo , Ácidos Cumáricos/metabolismo , Hordeum/metabolismo , Lignina/metabolismo , Triticum/metabolismo , Avena/química , Avena/crescimento & desenvolvimento , Parede Celular/química , Ácidos Cumáricos/química , Hordeum/química , Hordeum/crescimento & desenvolvimento , Lignina/química , Triticum/química , Triticum/crescimento & desenvolvimento
17.
Foods ; 9(10)2020 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-33050551

RESUMO

Cold plasma (CP) is generated when an electrical energy source is applied to a gas, resulting in the production of several reactive species such as ultraviolet photons, charged particles, radicals and other reactive nitrogen, oxygen, and hydrogen species. CP is a novel, non-thermal technology that has shown great potential for food decontamination and has also generated a lot of interest recently for a wide variety of food processing applications. This review discusses the potential use of CP in mainstream food applications to ensure food safety. The review focuses on the design elements of cold plasma technology, mode of action of CP, and types of CP technologies applicable to food applications. The applications of CP by the food industry have been demonstrated for food decontamination, pesticide residue removal, enzyme inactivation, toxin removal, and food packaging modifications. Particularly for food processing, CP is effective against major foodborne pathogenic micro-organisms such as Listeria monocytogenes and Salmonella Typhimurium, Tulane virus in romaine lettuce, Escherichia coli O157:H7, Campylobacter jejuni, and Salmonella spp. in meat and meat products, and fruits and vegetables. However, some limitations such as lipid oxidation in fish, degradation of the oligosaccharides in the juice have been reported with the use of CP, and for these reasons, further research is needed to mitigate these negative effects. Furthermore, more research is needed to maximize its potential.

18.
Cancer Res ; 80(3): 394-405, 2020 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-31776133

RESUMO

Over 80% of triple-negative breast cancers (TNBC) express mutant p53 (mtp53) and some contain oncogenic gain-of-function (GOF) p53. We previously reported that GOF mtp53 R273H upregulates the chromatin association of mini chromosome maintenance (MCM) proteins MCM2-7 and PARP and named this the mtp53-PARP-MCM axis. In this study, we dissected the function and association between mtp53 and PARP using a number of different cell lines, patient-derived xenografts (PDX), tissue microarrays (TMA), and The Cancer Genome Atlas (TCGA) database. Endogenous mtp53 R273H and exogenously expressed R273H and R248W bound to nascent 5-ethynyl-2´-deoxyuridine-labeled replicating DNA. Increased mtp53 R273H enhanced the association of mtp53 and PARP on replicating DNA. Blocking poly-ADP-ribose gylcohydrolase also enhanced this association. Moreover, mtp53 R273H expression enhanced overall MCM2 levels, promoted cell proliferation, and improved the synergistic cytotoxicity of treatment with the alkylating agent temozolomide in combination with the PARP inhibitor (PARPi) talazoparib. Staining of p53 and PARP1 in breast cancer TMAs and comparison with the TCGA database indicated a higher double-positive signal in basal-like breast cancer than in luminal A or luminal B subtypes. Higher PARP1 protein levels and PAR proteins were detected in mtp53 R273H than in wild-type p53-expressing PDX samples. These results indicate that mtp53 R273H and PARP1 interact with replicating DNA and should be considered as dual biomarkers for identifying breast cancers that may respond to combination PARPi treatments. SIGNIFICANCE: p53 gain-of-function mutant 273H and PARP1 interact with replication forks and could serve as potential biomarkers for breast cancer sensitivity to PARP inhibitors. GRAPHICAL ABSTRACT: http://cancerres.aacrjournals.org/content/canres/80/3/394/F1.large.jpg.


Assuntos
Replicação do DNA , DNA de Neoplasias/metabolismo , Mutação com Ganho de Função , Poli(ADP-Ribose) Polimerase-1/metabolismo , Neoplasias de Mama Triplo Negativas/patologia , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Antineoplásicos Alquilantes , Proliferação de Células , DNA de Neoplasias/genética , Feminino , Humanos , Componente 2 do Complexo de Manutenção de Minicromossomo/genética , Componente 2 do Complexo de Manutenção de Minicromossomo/metabolismo , Poli(ADP-Ribose) Polimerase-1/genética , Temozolomida/farmacologia , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/metabolismo
19.
Carbohydr Polym ; 223: 115075, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31426960

RESUMO

The use of carbon dioxide-argon gas radio frequency cold plasma in modifying waxy rice, maize and potato was explored in this paper. Treatment with plasma at 120 W or 0 W (carbon dioxide-argon gas mixture only) resulted in significant increases in the enthalpy of gelatinization of all three waxy starches. Treatment with plasma or gas resulted in a significant increase in the resistant starch content of maize and potato with rice increasing only after gas treatment. Significant decreases were observed in the setback and final viscosities after 120 W treatment in all starches. Plasma and gas treatment resulted in a 5.5% and 2.8% decrease in crystallinity of potato but not rice and maize starch. NMR results showed the presence of V-type single helices in mostly maize and rice starches. Carbon dioxide-argon radio frequency cold plasma served as a useful tool in modifying the properties of all three waxy starches.

20.
Foods ; 8(8)2019 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-31405124

RESUMO

Progress in breeding of intermediate wheatgrass (Thinopyrum intermedium), a perennial grain with environmental benefits, has enabled bran removal. Thus, determination of optimum milling conditions for production of refined flours is warranted. This study explored the effect of tempering conditions on intermediate wheatgrass flour properties, namely composition, color, solvent retention capacity, starch damage, and polyphenol oxidase activity. Changes in flour attributes were evaluated via a 3 × 3 × 2 factorial design, with factors targeting moisture (comparing un-tempered controls to samples of 12% and 14% target moisture), time (4, 8, and 24 h), and temperature (30 and 45 °C). All investigated parameters were significantly affected by target moisture; however, samples tempered to 12% moisture showed few differences to those tempered to 14%. Similarly, neither tempering time nor temperature exerted pronounced effects on most flour properties, indicating water uptake was fast and not dependent on temperature within the investigated range. Lactic acid retention capacity significantly correlated with ash (r = -0.739, p < 0.01), insoluble dietary fiber (r = -0.746, p < 0.01), polyphenol oxidase activity (r = -0.710, p < 0.01), starch content (r = 0.841, p < 0.01), and starch damage (r = 0.842, p < 0.01), but not with protein (r = 0.357, p > 0.05). In general, tempering resulted in flour with less bran contamination but only minor losses in protein.

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