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1.
PLoS Comput Biol ; 19(11): e1011623, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37939200

RESUMO

Recent breakthrough in spatial transcriptomics has brought great opportunities for exploring gene regulatory networks (GRNs) from a brand-new perspective. Especially, the local expression patterns and spatio-temporal regulation mechanisms captured by spatial expression images allow more delicate delineation of the interplay between transcript factors and their target genes. However, the complexity and size of spatial image collections pose significant challenges to GRN inference using image-based methods. Extracting regulatory information from expression images is difficult due to the lack of supervision and the multi-instance nature of the problem, where a gene often corresponds to multiple images captured from different views. While graph models, particularly graph neural networks, have emerged as a promising method for leveraging underlying structure information from known GRNs, incorporating expression images into graphs is not straightforward. To address these challenges, we propose a two-stage approach, MIGGRI, for capturing comprehensive regulatory patterns from image collections for each gene and known interactions. Our approach involves a multi-instance graph neural network (GNN) model for GRN inference, which first extracts gene regulatory features from spatial expression images via contrastive learning, and then feeds them to a multi-instance GNN for semi-supervised learning. We apply our approach to a large set of Drosophila embryonic spatial gene expression images. MIGGRI achieves outstanding performance in the inference of GRNs for early eye development and mesoderm development of Drosophila, and shows robustness in the scenarios of missing image information. Additionally, we perform interpretable analysis on image reconstruction and functional subgraphs that may reveal potential pathways or coordinate regulations. By leveraging the power of graph neural networks and the information contained in spatial expression images, our approach has the potential to advance our understanding of gene regulation in complex biological systems.


Assuntos
Drosophila , Redes Reguladoras de Genes , Animais , Drosophila/genética , Redes Reguladoras de Genes/genética , Biologia Computacional/métodos , Redes Neurais de Computação , Perfilação da Expressão Gênica/métodos
2.
Biomarkers ; : 1-16, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38923933

RESUMO

Background: RUNX3 is hypermethylated in multiple cancers. TIMP2 also functions as a regulator of tumors. However, there are only very few reports on the association of methylation of RUNX3 and TIMP2 with lung cancer (LC) in peripheral blood.Methods: 426 LC patients and 428 age- and sex-matched healthy controls were recruited. DNA methylation in blood was semi-quantitively assessed by mass spectrometry. For the association analysis, binary logistic regression analysis adjusted covariant was applied, and ORs were presented as per +10% methylation.Results: Hypermethylation of CpG_1, CpG_5and CpG_8 in RUNX3 was significantly associated with LC (ORs = 1.45, 1.35 and 1.35, respectively, adjusted p < 0.05), and even Stage I LC. The association between the three RUNX3 CpG sites and LC was enhanced by increased age (> 55 years, ORs ranged from 1.43 to 1.75, adjusted p < 0.05), male gender (ORs ranged from 1.47 to 1.59, adjusted p < 0.05) and tumor stage (Stage II&III&IV, ORs ranged from 1.86 to 3.03, adjusted p < 0.05).Conclusions: This study suggests a significant association between blood-based RUNX3 hypermethylation and LC, especially in elder people, in males and in LC patients with advanced stage.

3.
Bull Entomol Res ; 114(2): 210-229, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38444234

RESUMO

The Asian citrus psyllid, Diaphorina citri Kuwayama (Hemiptera: Psyllidae), is the key vector insect transmitting the Candidatus Liberibacter asiaticus (CLas) bacterium that causes the devastating citrus greening disease (Huanglongbing, HLB) worldwide. The D. citri salivary glands (SG) exhibit an important barrier against the transmission of HLB pathogen. However, knowledge on the molecular mechanism of SG defence against CLas infection is still limited. In the present study, we compared the SG transcriptomic response of CLas-free and CLas-infected D. citri using an illumine paired-end RNA sequencing. In total of 861 differentially expressed genes (DEGs) in the SG upon CLas infection, including 202 upregulated DEGs and 659 downregulated DEGs were identified. Functional annotation analysis showed that most of the DEGs were associated with cellular processes, metabolic processes, and the immune response. Gene ontology and Kyoto Encyclopaedia of Genes and Genomes enrichment analyses revealed that these DEGs were enriched in pathways involving carbohydrate metabolism, amino acid metabolism, the immune system, the digestive system, the lysosome, and endocytosis. A total of 16 DEGs were randomly selected to further validate the accuracy of RNA-Seq dataset by reverse-transcription quantitative polymerase chain reaction. This study provides substantial transcriptomic information regarding the SG of D. citri in response to CLas infection, which may shed light on the molecular interaction between D. citri and CLas, and provides new ideas for the prevention and control of citrus psyllid.


Assuntos
Hemípteros , Glândulas Salivares , Transcriptoma , Animais , Hemípteros/microbiologia , Hemípteros/genética , Glândulas Salivares/microbiologia , Glândulas Salivares/metabolismo , Doenças das Plantas/microbiologia , Citrus/microbiologia , Liberibacter
4.
Compr Rev Food Sci Food Saf ; 23(1): e13286, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38284581

RESUMO

Emerging nonthermal and thermal food processing technologies are a better alternative to conventional thermal processing techniques because they offer high-quality, minimally processed food. Texture is important in the food industry because it encompasses several product attributes and plays a vital role in consumer acceptance. Therefore, it is imperative to analyze the extent to which these technologies influence the textural attributes of food grains. Physical forces produced by cavitation are attributed to ultrasound treatment-induced changes in the conformational and structural properties of food proteins. Pulsed electric field treatment causes polarization of starch granules, damaging the dense outer layer of starch granules and decreasing the mechanical strength of starch. Prolonged radio frequency heating results in the denaturation of proteins and gelatinization of starch, thus reducing binding tendency during cooking. Microwave energy induces rapid removal of water from the product surface, resulting in lower bulk density, low shrinkage, and a porous structure. However, evaluating the influence of these techniques on food grain texture is difficult owing to differences in their primary operation mode, operating conditions, and equipment design. To maximize the advantages of nonthermal and thermal technologies, in-depth research should be conducted on their effects on the textural properties of different food grains while ensuring the selection of appropriate operating conditions for each food grain type. This article summarizes all recent developments in these emerging processing technologies for food grains, discusses their potential applications and drawbacks, and presents prospects for future developments in food texture enhancement.


Assuntos
Manipulação de Alimentos , Qualidade dos Alimentos , Manipulação de Alimentos/métodos , Culinária , Amido/química , Grão Comestível
5.
Opt Express ; 31(4): 5242-5256, 2023 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-36823810

RESUMO

Based on the intramolecular energy transfer mechanism between organic ligand TMHD (2, 2, 6, 6-tetramethyl-3, 5-heptanedione) and central Er3+ ions, optical gains at 1.55 µm were demonstrated in three structures of polymer waveguides using complex Er(TMHD)3-doped polymethylmethacrylate (PMMA) as the active material. With the excitation of two low-power UV light-emitting diodes (LEDs) instead of 980 or 1480 nm lasers, relative gains of 3.5 and 4.1 dB cm-1 were achieved in a 1-cm-long rectangular waveguide with an active core of Er(TMHD)3-doped PMMA polymer. Meanwhile, relative gain of 3.0 dB cm-1 was obtained in an evanescent-field waveguide with cross-section of 4 × 4 µm2 using passive SU-8 polymer as core and a ∼1-µm-thick Er(TMHD)3-doped PMMA as upper cladding. By growing a 100 nm thick aluminum mirror and active lower cladding, the optical gain was doubled to 6.7 dB cm-1 in evanescent-field waveguides because of the stimulated excitation of Er3+ ions in the upper and lower cladding and the improved absorption efficiency.

6.
BMC Cancer ; 23(1): 133, 2023 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-36759763

RESUMO

BACKGROUND: Transporter associated with antigen processing 1 (TAP1) is a molecule involved in processing and presentation of major histocompatibility complex class I restricted antigens, including tumor-associated antigens. TAP1 participates in tumor immunity, and is aberrantly expressed in multiple cancer types; METHODS: Transcriptome profiles were obtained from The Cancer Genome Atlas and Genotype-Tissue Expression databases. Genetic alterations, protein distribution, and interaction information for TAP1 were downloaded from cBioPortal, Human Protein Atlas and Compartmentalized Protein-Protein Interaction, respectively. Single-cell analyses of TAP1 across cancers were conducted via the Tumor Immune Single-cell Hub website. Gene set enrichment analysis was employed to investigate TAP1-associated functional mechanisms and processes. Immune cell infiltration was explored using Tumor Immune Estimation Resource 2.0. Pan-cancer correlations between TAP1 expression and immunotherapy biomarkers were explored using the Spearman's correlation test. Associations with immunotherapy responses were also investigated using clinicopathological and prognostic information from cohorts of patients with cancer receiving immune checkpoint inhibitors. RESULTS: TAP1 expression was elevated in most cancer types and exhibited distinct prognostic value. Immune cells expressed more TAP1 than malignant cells within most tumors. TAP1 expression was significantly correlated with immune-related pathways, T-lymphocyte infiltration, and immunotherapeutic biomarkers. Clinical cohort validation revealed a significant correlation with immune therapeutic effects and verified the prognostic role of TAP1 in immunotherapy. Western blot assay indicated that TAP1 is upregulated in glioblastoma compared with adjacent normal brain tissues. CONCLUSION: TAP1 is a robust tumor prognostic biomarker and a novel predictor of clinical prognosis and immunotherapeutic responses in various cancer types.


Assuntos
Apresentação de Antígeno , Glioblastoma , Humanos , Biomarcadores Tumorais , Western Blotting , Imunoterapia , Proteínas de Membrana Transportadoras , Prognóstico , Membro 2 da Subfamília B de Transportadores de Cassetes de Ligação de ATP/genética
7.
Crit Rev Food Sci Nutr ; : 1-17, 2023 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-37377348

RESUMO

Protein is one of the most important components of food which significantly contributes to the structure, functionality, and sensory properties which may affect consumer acceptability of processed products. Conventional thermal processing affects protein structure and induce undesirable degradation of food quality. This review provides an overview of emerging pretreatment and drying technologies (plasma treatment, ultrasound treatment, electrohydrodynamic, radio frequency, microwave, and superheated steam drying) in food processing by assessing protein structural changes to enhance functional and nutritional properties. In addition, mechanisms and principles of these modern technologies are described while challenges and opportunities for the development of these techniques in the drying process are also critically analyzed. Plasma discharges can lead to oxidative reactions and cross-linking of proteins that can change the structure of proteins. Microwave heating contributes to the occurrence of isopeptide or disulfide bonds which promotes α-helix and ß-turn formation. These emerging technologies can be adopted to improve protein surface by exposing more hydrophobic groups which restrict water interaction. It is expected that these innovative processing technologies should become a preferred choice in the food industry for better food quality. Moreover, there are some limitations for industrial scale application of these emerging technologies that need to be addressed.

8.
J Clin Lab Anal ; 37(17-18): e24499, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35576500

RESUMO

BACKGROUND: Due to the significant role of dyslipidemia, cardiovascular diseases (CVDs) are very common in obstructive sleep apnea (OSA). Nontraditional lipid indices are considered to be a better predictive index for cardiovascular risk. Nevertheless, the association between nontraditional lipid profiles and the severity of OSA is not clear. METHODS: A retrospective study was proceeded on 635 patients. Subjects were diagnosed with OSA through polysomnography (PSG). The association between severe OSA and nontraditional lipid profiles [triglyceride (TG)/high-density lipoprotein cholesterol (HDL-C) ratio, total cholesterol (TC)/HDL-C ratio, low-density lipoprotein cholesterol (LDL-C)/HDL-C ratio, non-high-density lipoprotein cholesterol (non-HDL-C), atherogenic index (AI), and lipoprotein combine index (LCI)] was examined by utilizing the restricted cubic spline and multivariate logistic regression analysis. RESULTS: All nontraditional lipid indices had positive relationships with the severity of OSA. By multivariable adjustment, the per SD increment of the TG/HDL-C, TC/ HDL-C, LDL-C/HDL-C, non-HDL-C, AI, and LCI were significantly associated with 88%, 50%, 42%, 40%, 50%, and 125% higher risk for severe OSA respectively. Compared with the lowest tertiles, the adjusted ORs (95% CI) were 2.42 (1.57-3.75), 2.39 (1.53-3.73), 2.35 (1.52-3.64), 1.86 (1.21-2.86), 2.39 (1.53-3.73), and 2.23 (1.43-3.48) for the top tertiles of TG/HDL-C, TC/ HDL-C, LDL-C/HDL-C, non-HDL-C, AI, and LCI respectively. CONCLUSION: All nontraditional lipid indices had positive relationship with the severity of OSA. In addition, TG/HDL-C, TC/HDL-C, and AI had better performance than the other nontraditional lipid indices for predicting severe OSA. These findings could help to determine the risk of cardiovascular diseases and improve the dyslipidemia management of OSA patients.


Assuntos
Aterosclerose , Doenças Cardiovasculares , Dislipidemias , Apneia Obstrutiva do Sono , Humanos , Estudos Retrospectivos , LDL-Colesterol , Doenças Cardiovasculares/complicações , Apneia Obstrutiva do Sono/diagnóstico , Triglicerídeos , Colesterol , HDL-Colesterol , Dislipidemias/epidemiologia , Dislipidemias/complicações
9.
J Sci Food Agric ; 103(1): 195-204, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-35860991

RESUMO

BACKGROUND: Insoluble dietary fiber (IDF) has beneficial physiological effects, such as the promoting of intestinal peristalsis, the improving of intestinal flora, and the absorbing of some harmful substances. Okara, a byproduct of soybean processing, is a potential source of IDF. But the larger particle size and poor water solubility of okara IDF have adverse effects on sensory properties and functional characteristics. Therefore, we used an emerging type of physical method is electron beam irradiation (EBI) to modify okara, and investigated that the effects of EBI doses on the structure and functional properties of okara IDF. RESULTS: It was found that the electron beam treatment damaged the crystalline structure of IDF. Observation of the surface of EBI-treated IDF revealed a loose and porous morphology rather than the typical smooth structure. At a dose of 6 kGy, a smallest particle size and largest specific surface area of IDF was obtained, and these factors increased the apparent viscosity of an IDF dispersion. The water holding capacity, swelling capacity and the oil holding capacity upon irradiation at 6 kGy increased 74.13%, 84.76% and 41.62%, respectively. In addition, the capacity for adsorption of cholesterol, sodium cholate, glucose and nitrite ion were improved after electron beam treatment. CONCLUSION: The modified okara IDF showed improved particle sizes and hydration properties, and these changes correlated with an improvement to the rough taste of IDF and improvements to the texture and storage period upon supplementation into food. © 2022 Society of Chemical Industry.


Assuntos
Fibras na Dieta , Elétrons , Glycine max/química , Adsorção , Água
10.
J Sci Food Agric ; 103(13): 6180-6189, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37139635

RESUMO

BACKGROUND: Plant protein is widely used in the study of animal protein substitutes and healthy sustainable products. The gel properties are crucial for the production of plant protein foods. Therefore, the present study investigated the use of soybean oil to modulate the gel properties of soybean protein isolation-wheat gluten composite with or without CaCl2 . RESULTS: Oil droplets filled protein network pores under the addition of soybean oil (1-2%). This resulted in an enhanced gel hardness and water holding capacity. Further addition of soybean oil (3-4%), oil droplets and some protein-oil compounds increased the distance between the protein molecule chain. The results of Fourier transform infrared spectroscopy and intermolecular interaction also showed that the disulfide bond and ß-sheet ratio decreased in the gel system, which damaged the overall structure of the gel network. Compared with the addition of 0 m CaCl2 , salt ion reduced the electrostatic repulsion between proteins, and local protein cross-linking was more intense at 0.005 m CaCl2 concentration. In the present study, structural properties and rheological analysis showed that the overall strength of the gel was weakened after the addition of CaCl2 . CONCLUSION: The presence of appropriate amount of soybean oil can fill the gel pores and improve the texture properties and network structure of soy protein isolate-wheat gluten (SPI-WG) composite gel. Excessive soybean oil may hinder protein-protein interaction and adversely affect protein gel. In addition, the presence or absence of CaCl2 significantly affected the gelling properties of SPI-WG composite protein gels. © 2023 Society of Chemical Industry.


Assuntos
Óleo de Soja , Proteínas de Soja , Proteínas de Soja/química , Triticum/química , Cloreto de Cálcio/química , Glutens/química , Géis/química
11.
J Sci Food Agric ; 103(4): 2057-2069, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36541590

RESUMO

BACKGROUND: High-pressure homogenization (HPH) is commonly used as a non-thermal processing technique for soybean and soy protein products, and the preparation of soy protein gel products often requires the synergistic effect of HPH and heat treatment. The dissociative association behavior of 11 S is the key to the protein gel formation state. In this study, therefore, 11 S thermal gels were prepared by high-pressure homogenization and co-induction (90 °C, 30 min) (adding Ca2+ to promote gel formation before heat treatment), and the effects of different high-pressure homogenization pressures (0-100 MPa) and co-treatment on the dissociative association behavior of 11 S protein, gel properties, and microstructure of 11 S gels were investigated. RESULTS: The results showed that HPH at higher pressures led to the breaking of disulfide bonds of aggregates and disrupted non-covalent interactions in protein aggregates, leading to collisions between protein aggregates and the reduction of large protein aggregates. High-pressure homogenization treatment at 60 MPa improved the gel properties of 11 S more. The HPH combined with heating changed the binary and tertiary structure of 11 S soy globulin and enhanced the hydrophobic interaction between 11 S molecules, thus improving the gel properties of 11 S. The change in intermolecular forces reflected the positive effect of HPH treatment on the formation of denser and more homogeneous protein gels. CONCLUSION: In conclusion, high-pressure homogenization combined with heating can improve the properties of 11 S gels by changing the structure of 11 S protein, providing data and theoretical support for soy protein processing and its further applications. © 2022 Society of Chemical Industry.


Assuntos
Globulinas , Glycine max , Proteínas de Soja/química , Agregados Proteicos , Géis/química
12.
J Sci Food Agric ; 103(12): 5992-6004, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37115040

RESUMO

BACKGROUND: Due to the extrusion black box effect, polysaccharides determine the formation of meat-like fibrous structures by modulating the flow behaviour and structural changes of plant proteins under high-moisture extrusion conditions. However, there is limited knowledge on the mechanism of resolution. This study simulated the rheological properties of soy protein-wheat protein under 57% moisture conditions with addition of 4% sodium alginate (SA), 2% xanthan gum (XG), and 2% maltodextrin (MD). The effect of these polysaccharides on the aggregation behaviour and conformation of raw protein during high-moisture extrusion was investigated. RESULTS: It was revealed that the three polysaccharides were effective in increasing the interaction between proteins and between proteins and water. Among them, 4% SA elicited a significantly stronger storage modulus (gelation behaviour) compared to the control. Analysis of different zones of extrudates by protein electrophoresis, particle size, and turbidity showed that SA-4% was able to form more high molecular protein aggregates (> 245 kDa) and promoted crosslinking of low molecular subunits (< 48 kDa), resulting in moderately sized protein aggregated particles. Fluorescence and ultraviolet spectra showed the transformation of protein tertiary structures in different extrusion zones, confirming that the key extrusion zone for protein conformational transformation by polysaccharides is the die-cooling zone. Furthermore, stretching of polypeptide chains and accelerated protein rearrangement facilitated the formation of more fibrillar structures. CONCLUSION: Theoretical support for polysaccharide modulation of plant protein quality in high moisture extruded products is provided by this study. © 2023 Society of Chemical Industry.


Assuntos
Agregados Proteicos , Proteínas de Soja , Proteínas de Soja/química , Triticum/química , Proteínas de Plantas/química , Carne
13.
J Sci Food Agric ; 102(14): 6273-6284, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35510347

RESUMO

BACKGROUND: Protein-polysaccharide complexes have been widely used to stabilize high-internal-phase emulsion (HIPEs). However, it is still unknown whether soy protein isolate-dextran (SPI-Dex) complexes can stabilize HIPEs or what is the effect of Dex concentration on the HIPEs. Furthermore, the non-covalent interaction mechanism between SPI and Dex is also unclear. Therefore, we fabricated SPI-Dex complexes and used them to stabilize HIPEs-loaded quercetin and explore the interaction mechanism between SPI and Dex, as well as the effect of Dex concentration on the particle size, ζ-potential, microstructure, rheology, quercetin encapsulation efficiency, and gastrointestinal fate of the HIPEs. RESULTS: Spectral analysis (fourier transform infrared spectroscopy, ultraviolet spectroscopy, and fluorescence spectroscopy) results identified the formation of SPI-Dex complexes, and indicated that the addition of Dex changed the spatial structure of SPI, whereas thermodynamic analysis (ΔH > 0, ΔS > 0) showed that hydrophobic interactions were the main driving forces in the formation of SPI-Dex complexes. Compared with HIPEs stabilized by SPI, the SPI-Dex complex-stabilized HIPEs had smaller particles (3000.33 ± 201.22 nm), as well as higher ζ-potential (-21.73 ± 1.10 mV), apparent viscosities, modulus, and quercetin encapsulation efficiency (98.19 ± 0.14%). In addition, in vitro digestion revealed that SPI-Dex complex-stabilized HIPEs significantly reduced the release of free fatty acid and improved quercetin bioaccessibility. CONCLUSION: HIPEs stabilized by SPI-Dex complexes delayed the release of free fat acid and improved the bioaccessibility of quercetin, and may be help in designing delivery systems for bioactive substances with specific properties. © 2022 Society of Chemical Industry.


Assuntos
Quercetina , Proteínas de Soja , Dextranos , Emulsões/química , Ácidos Graxos não Esterificados , Tamanho da Partícula , Polissacarídeos , Proteínas de Soja/química
14.
Analyst ; 146(11): 3623-3632, 2021 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-33929479

RESUMO

DNA methylation is a critical part of epigenetics and plays a vital role in maintaining normal cell function, genetic imprinting, and human tumorigenesis. Thus, it is important to develop a sensitive method for the determination of DNA methyltransferase (MTase) activity. Here, we present a simple and sensitive method based on single molecule fluorescence correlation spectroscopy (FCS) and polystyrene polymer dots (PS Pdots) for the quantitative detection of DNA adenine methylation (Dam) MTase activity and its inhibitor screening in homogeneous solution without separation. Its principle is based on the measurement of the characteristic diffusion time (τD) of unmethylated and methylated DNA-fluorescent probes by FCS. A hairpin DNA probe including the 5'-GATC-3' sequence is used by doubly labelling fluorophore Alexa Fluor 488 (Alexa 488) and biotin at the 5'- and 3'-terminus, respectively. Dam MTase catalyzed the methylation of the sequence of 5'-GATC-3', and DpnI cleaved the sequence of 5'-G-Am-TC-3'. Streptavidin conjugated PS Pdots were used to react with DNA probes without methylation to further increase the difference in τD values between methylated and unmethylated DNA-Alexa 488 probes. We used the FCS method to measure the τD values of DNA-Alexa 488 probes and further obtained the activity of Dam MTase. It is found that the τD value of the methylated DNA probe is negatively correlated with the logarithm of Dam MTase concentration in the range from 0.025 U mL-1 to 3 U mL-1. The detection limit is as low as 0.025 U mL-1. Furthermore, we evaluated the inhibition effect of drug-related DNA methylation and the half-maximal inhibitory concentration (IC50) value is consistent with a previous study. The results demonstrated that our proposed method will become a promising platform for the determination of Dam MTase activity and inhibitor screening.


Assuntos
Técnicas Biossensoriais , DNA Metiltransferases Sítio Específica (Adenina-Específica) , DNA/genética , Metilação de DNA , Humanos , Polímeros , Poliestirenos , DNA Metiltransferases Sítio Específica (Adenina-Específica)/genética , DNA Metiltransferases Sítio Específica (Adenina-Específica)/metabolismo
15.
J Synchrotron Radiat ; 27(Pt 1): 83-89, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31868740

RESUMO

Surface polarity with different crystal orientations has been demonstrated as a crucial parameter in determining the physical properties and device applications in many transition metal oxide and semiconductor compound systems. The influences of surface polarity on electronic structures in nitrogen-incorporated ZnO lattices have been investigated in the present work. The successful doping of nitrogen atoms in ZnO lattices is suggested by the existence of N-related chemical bonds obtained from X-ray photoelectron spectroscopy analysis where a pronounced N-Zn peak intensity has been observed in the (000\bar 1)-terminated polar ZnO compound compared with the (10\bar 10)-terminated nonpolar ZnO compound. An energy shift of the valence band maximum towards the Fermi level has been resolved for both polar and nonpolar ZnO lattices, whereas a charge redistribution of the O 2p hybridized states is only resolved for o-plane ZnO with a polar surface. Angular-dependent X-ray absorption analyses at the O K-edge reveal enhanced surface-state contributions and asymmetric O 2p orbital occupations in the (000\bar 1)-terminated o-plane ZnO compound. The results shed light on the efficient nitrogen doping in ZnO lattices with polar surfaces. The comprehensive electronic structure investigations of correlations between impurity doping and surface polarity in ZnO lattices may also offer guidance for the material design in other transition metal oxide and semiconductor systems.

16.
J Cell Mol Med ; 21(12): 3705-3717, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28714586

RESUMO

Oestrogens have been reported to attenuate acute inflammation in sepsis. In this study, the effects of long-term oestrogen replacement with 17ß-oestradiol (E2 ) on endotoxaemia-induced circulatory dysfunction and multiple organ dysfunction syndrome were evaluated in ovariectomized (Ovx) rats. E2 (50 µg/kg, s.c., 3 times/week) was administered for 8 weeks, followed by the induction of endotoxaemia by intravenous infusion of lipopolysaccharides (LPS; 30 mg/kg/4 hrs). Oestrogen deficiency induced by ovariectomy for 9 weeks augmented the LPS-induced damage, including endotoxic shock, myocardial contractile dysfunction, renal dysfunction and rhabdomyolysis. Cardiac levels of NF-κB p65, iNOS and oxidized glutathione, free radical production in skeletal muscles, myoglobin deposition in renal tubules, and plasma levels of plasminogen activator inhibitor-1, TNF-α, and IL-6 were more pronounced in the Ovx + LPS group than in the Sham + LPS group. Long-term treatment of E2 prevented this amplified damage in Ovx rats. Six hours after LPS initiation, activation of the autophagic process, demonstrated by increases in Atg12 and LC3B-II/LC3B-I ratios, and induction of haem oxygenase (HO)-1 and heat-shock protein (HSP) 70 protein expression in myocardium were increased significantly in the Ovx + E2  + LPS group. These results suggest that activation of autophagy and induction of HO-1 and HSP70 contribute to the protective effect of long-term E2 replacement on multiple organ dysfunction syndrome in endotoxaemia.


Assuntos
Anti-Inflamatórios/farmacologia , Autofagia/efeitos dos fármacos , Transtornos Cerebrovasculares/tratamento farmacológico , Endotoxemia/tratamento farmacológico , Estradiol/farmacologia , Insuficiência Renal/tratamento farmacológico , Rabdomiólise/tratamento farmacológico , Animais , Autofagia/genética , Proteína 12 Relacionada à Autofagia/genética , Proteína 12 Relacionada à Autofagia/metabolismo , Transtornos Cerebrovasculares/genética , Transtornos Cerebrovasculares/metabolismo , Transtornos Cerebrovasculares/patologia , Esquema de Medicação , Endotoxemia/genética , Endotoxemia/metabolismo , Endotoxemia/patologia , Feminino , Regulação da Expressão Gênica , Proteínas de Choque Térmico HSP70/genética , Proteínas de Choque Térmico HSP70/metabolismo , Heme Oxigenase-1/genética , Heme Oxigenase-1/metabolismo , Interleucina-6/genética , Interleucina-6/metabolismo , Lipopolissacarídeos , Óxido Nítrico Sintase Tipo II/genética , Óxido Nítrico Sintase Tipo II/metabolismo , Ovariectomia , Inibidor 1 de Ativador de Plasminogênio/genética , Inibidor 1 de Ativador de Plasminogênio/metabolismo , Ratos , Ratos Sprague-Dawley , Insuficiência Renal/genética , Insuficiência Renal/metabolismo , Insuficiência Renal/patologia , Rabdomiólise/genética , Rabdomiólise/metabolismo , Rabdomiólise/patologia , Fator de Transcrição RelA/genética , Fator de Transcrição RelA/metabolismo , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo
17.
J Cell Biochem ; 118(11): 3607-3615, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28618041

RESUMO

The present study introduced a direct co-culture of mouse ATDC5 cells and primary porcine chondrocytes into a microcavitary hydrogel, which possessed advantages in promoting the growth of chondrocytes and retaining the phenotype. These two types of cells were encapsulated with gelatin microspheres in alginate hydrogels in either of the three ratios (3:1, 1:1, or 1:3 of ATDC5 cells to chondrocytes) and cultured in chondrogenic medium for 28 days. Simultaneously, the single encapsulation of ATDC5 cells or chondrocytes was set as a control. Cell Counting Kit-8 (CCK-8), real-time PCR, and immunohistochemistry staining were used to evaluate the effect of various ratios of co-cultured ATDC5 cells and chondrocytes on the expression of the cartilaginous phenotype. The CCK-8 data indicated that the ratio of 3:1 group had an outstanding ability of cell growth. The other results demonstrated that higher the ATDC5 ratios and longer the culture duration, greater the expression of cartilage-specific genes (including type II collagen and aggrecan) and more the synthesized cartilaginous extracellular matrix. Also, the Western blot analysis suggested that p44/42 MAP Kinase was involved in cell proliferation. However, due to the direct co-culture of the two cell types, the underlying mechanism necessitates further investigation. Overall, the co-culture system in microcavitary hydrogel improved the effect of chondrogenesis and exhibited promising strategy for cartilage tissue engineering therapies. J. Cell. Biochem. 118: 3607-3615, 2017. © 2017 Wiley Periodicals, Inc.


Assuntos
Alginatos/química , Condrócitos/metabolismo , Regulação da Expressão Gênica , Hidrogéis/química , Animais , Linhagem Celular , Condrócitos/citologia , Técnicas de Cocultura , Ácido Glucurônico/química , Ácidos Hexurônicos/química , Camundongos , Suínos
18.
J Sep Sci ; 37(21): 3045-51, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25132205

RESUMO

A method based on matrix solid-phase dispersion extraction followed by ultra high performance liquid chromatography with tandem mass spectrometry is presented for the extraction and determination of phenolic compounds in Equisetum palustre. This method combines the high efficiency of matrix solid-phase dispersion extraction and the rapidity, sensitivity, and accuracy of ultra high performance liquid chromatography with tandem mass spectrometry. The influential parameters of the matrix solid-phase dispersion extraction were investigated and optimized. The optimized conditions were as follows: silica gel was selected as dispersing sorbent, the ratio of silica gel to sample was selected to be 2:1 (400/200 mg), and 8 mL of 80% methanol was used as elution solvent. Furthermore, a fast and sensitive ultra high performance liquid chromatography with tandem mass spectrometry method was developed for the determination of nine phenolic compounds in E. palustre. This method was carried out within <6 min, and exhibited satisfactory linearity, precision, and recovery. Compared with ultrasound-assisted extraction, the proposed matrix solid-phase dispersion procedure possessed higher extraction efficiency, and was more convenient and time saving with reduced requirements on sample and solvent amounts. All these results suggest that the developed method represents an excellent alternative for the extraction and determination of active components in plant matrices.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Equisetum/química , Fenóis/química , Extratos Vegetais/química , Extração em Fase Sólida/métodos , Espectrometria de Massas em Tandem/métodos , Limite de Detecção , Fenóis/isolamento & purificação , Extratos Vegetais/isolamento & purificação
19.
Insects ; 15(6)2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38921110

RESUMO

An increasing body of research has underscored the significant impact of non-consumptive effects on the dynamics of prey pests, encompassing growth, development, reproduction, and metabolism across various vertebrate and invertebrate taxa, rivaling the influence of consumption effects. In our investigation, we delved into the non-consumptive effects exerted by the natural predatory enemy Harmonia axyridis on the reproductive capacity and metabolism of Spodoptera frugiperda adults. Our findings revealed a substantial decrease in the reproductive ability of S. frugiperda adults when exposed to the non-consumptive effects of H. axyridis. Concurrently, we observed an elevation in hydrogen peroxide (H2O2) content and the activities of antioxidant enzymes such as superoxide dismutases (SODs), catalases (CATs), and peroxidases (PODs). Furthermore, notable alterations were detected in energy metabolism, characterized by heightened triglyceride levels and diminished glycogen and trehalose concentrations. These outcomes underscored the adaptive response of the pest aimed at mitigating non-consumptive adverse effects by augmenting antioxidant enzyme activity to counteract oxidative stress and minimize cellular damage. Nonetheless, this defensive mechanism entails a significant expenditure of energy resources, resulting in shifts in energy utilization. Elevated triglyceride levels and reduced glycogen and trehalose concentrations diminish available resources for reproductive processes, such as egg laying, ultimately culminating in decreased fecundity. This study contributes novel insights into the non-consumptive effects observed in insects, while also furnishing valuable insights into the mechanisms underlying insect stress responses.

20.
Int J Biol Macromol ; 254(Pt 3): 127943, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37951435

RESUMO

To enrich the application of nanocomposite hydrogels, we introduced two types of nanocellulose (CNC, cellulose nanocrystals; CNF, cellulose nanofibers) into the soy protein isolate(SPI)- konjac glucomannan (KGM) composite hydrogel system, respectively. The similarities and differences between the two types of nanocellulose as textural improvers of composite gels were successfully explored, and a model was developed to elaborate their interaction mechanisms. Appropriate levels of CNC (1.0 %) and CNF (0.75 %) prolonged SPI denaturation within the system, exposed more buried functional groups, improved molecular interactions, and strengthened the honeycomb structural skeleton formed by KGM. The addition of CNC resulted in greater gel strength (SKC1 2708.53 g vs. Control 810.35 g), while the addition of CNF improved the elasticity (SKF0.75 1940.24 g vs. Control 405.34 g). This was mainly attributed to the reinforcement of the honeycomb-structured, water binding and trapping, and the synergistic effect of covalent (disulfide bonds) and non-covalent interactions (hydrogen bonds, ionic bonds) within the gel network. However, the balance and interactions between proteins and polysaccharides were disrupted in the composite system with excessive CNF addition (≥0.75 %), which broken the stability of the honeycomb-like structure. We expect this study will draw attention on potential applications of CNC and CNF in protein-polysaccharide binary systems and facilitate the creation of novel, superior, mechanically strength-regulated nanofiber composite gels.


Assuntos
Hidrogéis , Proteínas de Soja , Hidrogéis/química , Celulose/química , Mananas/química , Cetonas
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