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1.
Adv Mater ; 36(5): e2305988, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37994230

RESUMO

Aqueous zinc-metal batteries are considered to have the potential for energy storage due to their high safety and low cost. However, the practical applications of zinc batteries are limited by dendrite growth and side reactions. Epitaxial growth is considered an effective method for stabilizing Zn anode, especially for manipulating the (002) plane of deposited zinc. However, (002) texture zinc is difficult to achieve stable cycle at high capacity due to its large lattice distortion and uneven electric field distribution. Here, a novel zinc anode with highly (101) texture (denoted as (101)-Zn) is constructed. Due to unique directional guidance and strong bonding effect, (101)-Zn can achieve dense vertical electroepitaxy in near-neutral electrolytes. In addition, the low grain boundary area inhibits the occurrence of side reactions. The resultant (101)-Zn symmetric cells exhibit excellent stability over 5300 h (4 mA cm-2 for 2 mAh cm-2 ) and 330 h (15 mA cm-2 for 10 mAh cm-2 ). Meanwhile, the cycle life of Zn//MnO2 full cell is meaningfully improved over 1000 cycles.

2.
Mater Today Bio ; 23: 100888, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38075250

RESUMO

Promoting the recovery of neurological function in patients with traumatic spinal cord injury (TSCI) remains challenging. The balance between astrocyte-mediated neurotrophic and pro-inflammatory responses is critical for TSCI repair. Recently, the utilization of nanomaterials has been considerably explored in immunological reconstructive techniques that specifically target astrocyte-mediated inflammation, yielding positive outcomes. In this review, we aim to condense the present knowledge regarding the astrocyte-mediated inflammation following TSCI. We then review the various categories of nanomaterials utilized in the management of astrocyte-mediated inflammation in TSCI and conclude by summarizing their functions and advantages to offer novel insights for the advancement of effective clinical strategies targeting TSCI.

3.
J Magn Reson Imaging ; 2023 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-38009385

RESUMO

BACKGROUND: Blood flow signals may be a confounder in quantifying T1 values of plaque or thrombus and how to realize black-blood T1 mapping remains a challenge task. PURPOSE: To develop a fast and three-dimensional black-blood T1 mapping technique for quantitative assessment of atherosclerosis and venous thrombosis. STUDY TYPE: Sequence development and optimization via phantoms and volunteers as well as pilot prospective. PHANTOM AND SUBJECTS: Numerical simulations, a standard phantom, 8 healthy volunteers (mean age, 22 ± 1 years; 5 males), and 19 patients (mean age, 57 ± 14 years; 13 males) with atherosclerosis or venous thrombosis. FIELD STRENGTH/SEQUENCE: 3T/inversion recovery spin-echo sequence (IR-SE), magnetization prepared 2 rapid acquisition gradient echoes (MP2RAGE), and black-blood prepared MP2RAGE (BB-MP2RAGE). ASSESSMENT: The black-blood preparation (i.e., delay alternating with nutation for tailored excitation, DANTE) was incorporated into MP2RAGE for black-blood T1 mapping. The BB-MP2RAGE was optimized numerically based on the Bloch equation, and then the phantom study was performed to verify the accuracy of T1 mapping by BB-MP2RAGE against IR-SE and MP2RAGE. Preliminary clinical validation was prospectively performed to assess the flow suppression effect and its potential application in plaque and thrombosis identification. STATISTICAL TESTS: Pearson correlation test, Bland-Altman analysis, paired t-test, and intraclass correlation coefficient. A P value <0.05 indicates a statistically significant difference. RESULTS: Phantom experiments showed comparable accuracy of T1 maps by BB-MP2RAGE with IR-SE and MP2RAGE (all r2 > 0.99); Compared to MP2RAGE, BB-MP2RAGE effectively nulled the blood flow signals, and had a significant improvement in contrast-to-noise ratio between static tissue and blood (250.5 ± 66.6 vs. 91.9 ± 35.9). BB-MP2RAGE can quantify plaque or thrombus T1 relaxation time with blood flow signal suppression. DATA CONCLUSION: Accurate T1 mapping with sufficient blood flow suppression was achieved by BB-MP2RAGE. BB-MP2RAGE has the potential to quantitatively characterize atherosclerosis and venous thrombosis. LEVEL OF EVIDENCE: 1 TECHNICAL EFFICACY: Stage 1.

4.
Artigo em Inglês | MEDLINE | ID: mdl-37903333

RESUMO

Many cathode materials store zinc ions based on the intercalation reaction mechanism in neutral aqueous Zn-ion batteries, and the structural design of the cathodes has been stuck in the curing mode by extending the ion diffusion channel. Here, we first develop halide ions to unlock the electrochemical activity of conversion-type Bi2O3 in aqueous Zn-ion batteries. Notably, the iodide ion shows the best performance compatibility with the Bi2O3 cathode. The electrochemical reaction mechanism studies show that iodide ions can be regarded as a redox medium to reduce the charge-transfer activation energy and motivate the conversion of Bi2O3 from Bi3+ to Bi0 during the cycle. Unsurprising, the discharge-specific capacity can reach 436.8 mAh g-1 at 0.5 A g-1 and achieve a cyclic lifespan of 6000 cycles at a current density of 3 A g-1. The activation of the Bi2O3 conversion reaction by iodide ions is of great significance for broadening the research range of ZIB cathode materials.

5.
Behav Res Methods ; 2023 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-37620745

RESUMO

Lexical databases are essential tools for studies on language processing and acquisition. Most previous Chinese lexical databases have focused on materials for adults, yet little is known about reading materials for children and how lexical properties from these materials affect children's reading comprehension. In the present study, we provided the first large database of 2999 Chinese characters and 2182 words collected from the official textbooks recently issued by the Ministry of Education (MOE) of the People's Republic of China for most elementary schools in Mainland China, as well as norms from both school-aged children and adults. The database incorporates key orthographic, phonological, and semantic factors from these lexical units. A word-naming task was used to investigate the effects of these factors in character and word processing in both adults and children. The results suggest that: (1) as the grade level increases, visual complexity of those characters and words increases whereas semantic richness and frequency decreases; (2) the effects of lexical predictors on processing both characters and words vary across children and adults; (3) the effect of age of acquisition shows different patterns on character and word-naming performance. The database is available on Open Science Framework (OSF) ( https://osf.io/ynk8c/?view_only=5186bd68549340bd923e9b6531d2c820 ) for future studies on Chinese language development.

6.
Heliyon ; 9(3): e13873, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36967925

RESUMO

As a security protection system, the marine interdiction system can be set up outside the port to provide security protection for the ships and facilities there as well as to prevent explosions and ship collisions. This paper uses the Arbitrary Lagrangian Euler (ALE) method in ANSYS LS/DYNA to simulate a blast for an interdiction system close to the water's surface. The simulated shock wave overpressure is extracted and fitted, and when compared with the empirical formula, it is discovered that the trend and value are in good agreement. In the case of controlled calculation scale, closer to the real situation and only consider the explosion transient effect, analysis of the dynamic reaction of the interdiction system under various operating situations to test its anti-explosion performance would help to confirm the validity of the proportional burst distance as a criterion for near-water explosion damage. The safe distance for a 500 kg TNT charge is 4.62 m, and the safe distance for a 1500 kg TNT charge is 6.37 m, when the proportional burst distance reaches 0.5, some of the cable tension reaches the breaking tension level at this moment, and foam floating balls appear to fail for some elements, but the system as a whole is still in a safe state. The research will also provide support for the optimization of the interdiction system and also provide support for the optimization and development of the marine interdiction system.

7.
J Agric Food Chem ; 71(14): 5525-5534, 2023 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-36989392

RESUMO

The microbial community structure in traditional fermented foods is quite complex, making the relationship between strains unclear. In this regard, the co-culture system can simulate microbial interactions during food fermentation and reveal the morphological changes, metabolic processes, and gene expression of microbial communities. The present study sought to investigate the effects of microbial interactions on the growth of Aspergillus oryzae and Zygosaccharomyces rouxii through omics. After co-cultivation, the pH value and dry weight were consistent with the pure culture of Z. rouxii. Additionally, the consumption of reducing sugar decreased, and the enzymatic activity increased compared with the pure culture of fungus. The analysis of volatile organic compounds (VOCs) and transcriptomics showed that co-culture significantly promoted the effect on Z. rouxii. A total of 6 different VOCs and 2202 differentially expressed genes were identified in the pure and co-culture of Z. rouxii. The differentially expressed genes were mainly related to the endonucleolytic cleavage of rRNA, ribosome biogenesis in eukaryotes, and RNA polymerase metabolic pathways. The study results will provide insights into the effect of microbial interactions on the growth of A. oryzae and Z. rouxii.


Assuntos
Zygosaccharomyces , Carboidratos , Fermentação , Perfilação da Expressão Gênica , Transcriptoma , Zygosaccharomyces/genética , Zygosaccharomyces/metabolismo , Aspergillus/genética , Aspergillus/metabolismo
8.
Magn Reson Imaging ; 96: 17-26, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36375762

RESUMO

PURPOSE: To develop and evaluate a sequence in which water excitation with lipid insensitive binomial off-resonant radio frequency excitation (LIBRE) pulses is incorporated into three-dimensional (3D) variable flip angle fast spin echo (LIBRE-vf-FSE) for fat-free and large field of view imaging at 3 Tesla (T). MATERIALS AND METHODS: Numerical simulation was conducted to optimize the parameters of LIBRE pulses, including the flip angle, pulse duration, and frequency offset, for maximizing the fat suppression effect of the proposed LIBRE-vf-FSE sequence. The sequence was then implemented at 3 T and assessed in phantoms, lower extremity imaging of 8 healthy volunteers, and head/neck imaging of 5 healthy volunteers. Conventional water excitation (WE) and fat saturation (FatSat) were also performed for comparison. Signal-to-noise ratio (SNR) of fat and contrast-to-noise ratio (CNR) between fat and water were used to evaluate the level of fat suppression. Standard deviation (SD) of SNR was used to evaluate the uniformity of fat suppression. RESULTS: The numerical simulation demonstrated that LIBRE-vf-FSE enables large volume imaging with uniform fat suppression, which was further confirmed by phantom and healthy volunteer experiments. LIBRE provided the lowest fat SNR and offered more uniform fat suppression compared with the WE and FatSat. Specifically, average oil SNRs obtained by LIBRE (1.10 ms, 360 Hz, and 60°), WE, and FatSat were (180.1 vs. 280.2 vs. 811.2) in phantom experiments, and average fat SNRs and SDs in legs obtained by LIBRE (1.10 ms, 360 Hz, and 60°), WE, and FatSat were (85.1 vs. 105.0 vs. 105.1) and (22.4 vs. 27.4 vs. 56.4) in vivo experiments, respectively. CONCLUSION: The proposed LIBRE-vf-FSE sequence allows for fat suppression and large field of view imaging at 3 T. It could be an alternative approach for fat-free vf-FSE scan.


Assuntos
Imageamento Tridimensional , Imageamento por Ressonância Magnética , Humanos , Imageamento Tridimensional/métodos , Imageamento por Ressonância Magnética/métodos , Água , Aumento da Imagem/métodos , Imagens de Fantasmas
9.
World J Gastrointest Surg ; 14(11): 1204-1218, 2022 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-36504521

RESUMO

BACKGROUND: As the lymph-node metastasis rate and sites vary among pancreatic head carcinomas (PHCs) of different T stages, selective extended lymphadenectomy (ELD) performance may improve the prognosis of patients with PHC. AIM: To investigate the effect of ELD on the long-term prognosis of patients with PHC of different T stages. METHODS: We analyzed data from 216 patients with PHC who underwent surgery at our hospital between January 2011 and December 2021. The patients were divided into extended and standard lymphadenectomy (SLD) groups according to extent of lymphadenectomy and into T1, T2, and T3 groups according to the 8th edition of the American Joint Committee on Cancer's staging system. Perioperative data and prognoses were compared among groups. Risk factors associated with prognoses were identified through univariate and multivariate analyses. RESULTS: The 1-, 2- and 3-year overall survival (OS) rates in the extended and SLD groups were 69.0%, 39.5%, and 26.8% and 55.1%, 32.6%, and 22.1%, respectively (P = 0.073). The 1-, 2- and 3-year disease-free survival rates in the extended and SLD groups of patients with stage-T3 PHC were 50.3%, 25.1%, and 15.1% and 22.1%, 1.7%, and 0%, respectively (P = 0.025); the corresponding OS rates were 65.3%, 38.1%, and 21.8% and 36.1%, 7.5%, and 0%, respectively (P = 0.073). Multivariate analysis indicated that portal vein invasion and lymphadenectomy extent were risk factors for prognosis in patients with stage-T3 PHC. CONCLUSION: ELD may improve the prognosis of patients with stage-T3 PHC and may be of benefit if performed selectively.

10.
Food Res Int ; 158: 111453, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35840191

RESUMO

Melanoidins, making general contribution to the food characteristics, are extensively generated in the production of Chinese traditional vinegar; however, their effect on flavor modification remains unknown. This study investigated the changes in the melanoidins of Zhenjiang aromatic vinegar (ZAV) during decoction, and the interactions of crude melanoidins (CM) and pure melanoidins (PM) from decocted and undecocted ZAV with mixed aroma compounds were compared. With the exception of CN, OH and CH, chemical bonds and groups varied among the four types of melanoidins. However, CM and PM, obtained from decocted or undecocted vinegar, displayed generally similar structures, which resulted in their consistent retention of volatiles owning to the overall structure characteristics. Compared to aqueous solution, CM and PM from undecocted vinegar exhibited release, non-influence, or adsorption of flavors. However, melanoidins from decocted vinegar appeared the adsorption for all flavors but 2,3,5,6-Tetramethylpyrazine with weakened release. Free low molecular weight (LMw) compounds would affect the volatiles retention. Total solids (TS) from undecocted vinegar adsorbed volatiles except diethyl succinate; however, TS from decocted vinegar released all flavors significantly. Therefore, the decocted melanoidins were beneficial for the persistence of aroma. This study provided a base for elucidating the formation of melanoidins in decoction procedure and their roles in flavor modification.


Assuntos
Ácido Acético , Polímeros , Ácido Acético/química , Alimentos , Odorantes , Polímeros/química
11.
Bioengineered ; 13(4): 8503-8514, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35332852

RESUMO

Cervical squamous cell carcinoma (CSCC), the most common cervical malignancy, is more likely to invade and metastasize than other cervical cancers. miR-125a, a tumor suppressor gene, has been confirmed to be associated with cancer metastasis. However, the role of miR-125a in CSCC and the underlying mechanism are unknown. miR-125a expression was confirmed by real-time quantitative PCR (RT-qPCR), and the Rad51 expression level was measured by western blotting analysis. CSCC cell proliferation, migration and invasion were assessed with functional assays, including CCK-8, colony formation, wound healing and Transwell assays. Our data confirmed that miR-125a is expressed at low levels in CSCC tissues and cells. Functionally, the overexpression of miR-125a greatly prevented the proliferation, migration and invasion of CSCC cells, and the inhibition of miR-125a expression strongly enhanced these behaviors in CSCC cells. Moreover, the expression of Rad51, a miR-125a target gene, greatly reversed the miR-125-mediated inhibition of CSCC cell proliferation, migration and invasion. In addition, we discovered that miR-125a downregulated the levels of phosphorylated PI3K, AKT and mTOR through Rad51 in CSCC cells. miR-125a, a tumor suppressor, can attenuate the malignant behaviors of CSCC cells by targeting Rad51. Therefore, the miR-125a/Rad51 axis might be a target for CSCC therapy.


Assuntos
Carcinoma de Células Escamosas , MicroRNAs , Rad51 Recombinase , Neoplasias do Colo do Útero , Carcinoma de Células Escamosas/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Feminino , Humanos , MicroRNAs/genética , Rad51 Recombinase/genética , Neoplasias do Colo do Útero/genética
12.
Biosens Bioelectron ; 203: 114055, 2022 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-35131695

RESUMO

Protein kinases play crucial regulatory roles in the physiological activities in the human body. Understanding protein kinase activity and its inhibition is essential for the management of human diseases. Considering the limitations of the existing protein kinase-related analysis methods, the aim of the present study was to develop a fluorescent biosensor based on Eu(BTC) (H2O)6 (BTC = 1,3,5-Benzenetricarboxylic acid) for evaluating protein kinase activity and the relevant inhibitors. A fluorophore-labelled substrate polypeptide was phosphorylated under the catalysis of protein kinase. This phosphorylated peptide can be coordinated explicitly with the europium site of Eu(BTC) (H2O)6 to detect the protein kinase. The developed biosensor performed well, with a detection limit of 0.00003 U µL-1, and it showed good selectivity and universality. Protein kinase activity could also be detected in MCF-7 cells using this method. Furthermore, in terms of inhibitor screening using the Eu(BTC) (H2O)6-based sensor, both H-89 and ellagic acid were found to inhibit protein kinase activity with IC50 values of 1.09 and 19.88 nmol L-1, respectively. Overall, this biosensor has broad application prospects in monitoring and controlling protein kinase activity.


Assuntos
Técnicas Biossensoriais , Estruturas Metalorgânicas , Técnicas Biossensoriais/métodos , Európio , Fosforilação , Proteínas Quinases/metabolismo
13.
Food Microbiol ; 103: 103966, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35082083

RESUMO

Aspergillus oryzae and Zygosaccharomyces rouxii are the perquisites microorganisms in food fermentation due to the broad application prospects of their secondary metabolites. The co-culture strategy simulates the naturally occurring ecology by developing artificial microbial communities. This strategy has also been widely adopted to investigate the novel secondary metabolites. In the present study, the effects of co-culture on extracellular and intracellular secondary metabolites of fungi in liquid culture were investigated through UPLC-QTOF-MS. Notably, A. oryzae could significantly inhibit the growth of Z. rouxii when A. oryzae and Z. rouxii were co-cultured. The results further indicated that the co-culture of fungi could affect the secondary metabolites and produce various metabolic pathways. Overall, this study will provide insights into fungal interactions and cell metabolism mechanisms, contributing to supplementing and enriching the fermentation potential of fungi.


Assuntos
Aspergillus oryzae , Zygosaccharomyces , Técnicas de Cocultura , Fermentação , Metabolômica
14.
J Food Sci ; 87(2): 714-727, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35049049

RESUMO

Soy sauce fermentation is largely mediated by bacteria, including several non-salt-tolerant bacterial species. The present study aimed to compare the use of Aspergillus oryzae alone or in co-inoculation with Lactobacillus plantarum or Enterococcus faecalis on the resulting enzymatic activity, content of phenolic compounds, free amino acids, organic acids, and antioxidant capacity of soy sauce. Co-inoculation significantly increased acid protease, ß-glucosidase, and pectinase activities during koji making. Additionally, the contents of total phenols, total flavonoids, organic acids, amino acids, isoflavones, as well as the antioxidant capacity were higher during moromi fermentation using co-inoculants compared to those obtained when A. oryzae was used as single inoculant. Overall, co-inoculation of A. oryzae with L. plantarum or E. faecalis during koji making was shown to effectively promote the production of active substances in soy sauce. PRACTICAL APPLICATION: In this study, Aspergillus oryzae in mixed inoculation with Lactobacillus plantarum or Enterococcus faecalis could be effectively used in koji making for soy sauce. The use of co-inoculants in koji making effectively promoted the production of active substances in soy sauce, hence it is improving health benefits, whilst diversifying the use of raw materials and the application value of soybean meal.


Assuntos
Aspergillus oryzae , Lactobacillus plantarum , Alimentos de Soja , Enterococcus faecalis , Fermentação
15.
Food Chem ; 365: 130495, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34243128

RESUMO

Lactobacillus enriched with organic/inorganic selenium and pickles fermented with the Lactobacillus plantarum R were prepared. The results showed that selenium-enriched Lactobacillus plantarum R enhanced the antioxidant capacity, inhibition rate of advanced glycation end-products (AGEs), nitrite degradation, and the organic acid production of fermented pickles, while Lactobacillus plantarum R enriched with inorganic selenium (R-Se-IN) showed the best performance. Twenty-three aroma-active substances and seven characteristic compounds were detected in the R-Se-IN group. Moreover, the bacterial community result revealed that Lactococcus, Lactobacillus, and Leuconostoc were predominant in the R-Se-IN group, while the other groups contained Enterobacter, Halomonas, and Klebsiella. Furthermore, the correlations between environmental factors, differential flavor substances, and microbial communities were explored based on multivariate statistical analysis. These results indicate that the addition of Lactobacillus plantarum R enriched with organic/inorganic selenium influenced the environmental factors, differential flavor substances, and microbial communities of the fermented pickles.


Assuntos
Alimentos Fermentados , Lactobacillus plantarum , Microbiota , Selênio , Fermentação , Lactobacillus
16.
Brain Struct Funct ; 226(5): 1627-1639, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33866405

RESUMO

Writing sequences play an important role in handwriting of Chinese characters. However, little is known regarding the integral brain patterns and network mechanisms of processing Chinese character writing sequences. The present study decoded brain patterns during observing Chinese characters in motion by using multi-voxel pattern analysis, meta-analytic decoding analysis, and extended unified structural equation model. We found that perception of Chinese character writing sequence recruited brain regions not only for general motor schema processing, i.e., the right inferior frontal gyrus, shifting, and inhibition functions, i.e., the right postcentral gyrus and bilateral pre-SMA/dACC, but also for sensorimotor functions specific for writing sequences. More importantly, these brain regions formed a cooperatively top-down brain network where information was transmitted from brain regions for general motor schema processing to those specific for writing sequences. These findings not only shed light on the neural mechanisms of Chinese character writing sequences, but also extend the hierarchical control model on motor schema processing.


Assuntos
Imageamento por Ressonância Magnética , Redação , Encéfalo , Mapeamento Encefálico , China , Escrita Manual , Humanos , Reconhecimento Visual de Modelos , Leitura
17.
Microb Biotechnol ; 14(2): 517-534, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32954686

RESUMO

Myriocin, which is produced by Bacillus amyloliquefaciens LZN01, can inhibit the growth of Fusarium oxysporum f. sp. niveum (Fon). In the present study, the antifungal mechanism of myriocin against Fon was investigated with a focus on the effects of myriocin on the cell membrane. Myriocin decreased the membrane fluidity and destroyed the membrane integrity of Fon. Significant microscopic morphological changes, including conidial shrinkage, the appearance of larger vacuoles and inhomogeneity of electron density, were observed in myriocin-treated cells. A membrane-targeted mechanism of action was also supported by transcriptomic and proteomic analyses; a total of 560 common differentially expressed genes (DEGs) and 285 common differentially expressed proteins (DEPs) were identified. The DEGs were further verified by using RT-qPCR. The combined analysis between the transcriptome and proteome revealed that the expression of some membrane-related genes and proteins, mainly those related to sphingolipid metabolism, glycerophospholipid metabolism, steroid biosynthesis, ABC transporters and protein processing in the endoplasmic reticulum, was disordered. Myriocin affected the serine palmitoyl transferase (SPT) activity as evidenced through molecular docking. Our results indicate that myriocin has significant antifungal activity owing to its ability to induce membrane damage in Fon.


Assuntos
Bacillus amyloliquefaciens , Citrullus , Fusarium , Ácidos Graxos Monoinsaturados , Simulação de Acoplamento Molecular , Doenças das Plantas , Proteômica
18.
Anal Chim Acta ; 1128: 99-106, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32825917

RESUMO

In this work, we used a titanium-based metal-organic framework (MOF, Ti-MIL125-NH2) as a novel enrichment platform to detect protein kinase A (PKA) activity and to screen relevant kinase inhibitors. This method took advantage of the highly specific recognition of phosphate groups by the Ti-MIL125-NH2 nanoparticle. In the presence of PKA and adenosine 5'-triphosphate (ATP), the fluorophore-labeled peptide substrate was phosphorylated, and the generated phosphopeptide could then specifically bind to the titanium sites of Ti-MIL125-NH2. This resulted in fluorescence enrichment, which could be efficiently detected by the system. Under optimal conditions, the method presented a linear relationship in the experimental range of 0.00005-0.01 U µL-1, and the limit of detection was 0.00003 U µL-1 (3σ, n = 11). Furthermore, protein kinase Akt1 was tested to verify the universality of this method. The method was also successfully applied in cell lysates for kinase activity analysis and inhibitor screening. Thus, the new, highly sensitive fluorescence method based on MOF for detecting PKA activity is an excellent tool that has potential applications in kinase-related disease and basic research.


Assuntos
Estruturas Metalorgânicas , Fosfopeptídeos , Fosforilação , Proteínas Quinases/metabolismo , Titânio
19.
Arch Microbiol ; 202(8): 2169-2179, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32519022

RESUMO

Bacillus methylotrophicus has been demonstrated to promote growth of various plants, whereas the promoting effect of B. methylotrophicus on rice growth has been rarely reported. In this study, B. methylotrophicus DD-1, capable of efficiently promoting the growth of rice, was isolated from the root soil of rice plants. The isolate exhibited potassium-solubilizing (1.18 mg/L), Indole-3-acetic acid (IAA) (87.26 mg/L), Gibberellic acid (GA) (25.91 mg/L) and Siderophore production activity (52.32%). As indicated from the result, plant growth parameters (e.g., dry weight, tiller number, root and shoot length) of rice seedlings treated with the isolate DD-1 were more effective than those of the control group in pot and soilless culture experiments. Moreover, the adsorption capacity of rice roots which were soaked in the bacterial suspension of isolate increased with the increase in concentration and absorption time. In sterilized and unsterilized soil, conformation of root colonization activity by bacterial isolate established by its nearer existence to the rice root. Thus, the B. methylotrophicus DD-1 enhances plant growth promotion by multifarious growth promoting and root colonization traits, thereby augmenting potassium level in soil. Henceforth, the potential bacterium could be exploited for the development of biological fertilizer, leading towards sustainable agronomy.


Assuntos
Bacillus/fisiologia , Oryza/microbiologia , Raízes de Plantas/microbiologia , Plântula/microbiologia , Microbiologia do Solo , Bacillus/isolamento & purificação , Giberelinas/metabolismo , Ácidos Indolacéticos/metabolismo , Oryza/crescimento & desenvolvimento , Desenvolvimento Vegetal , Plântula/crescimento & desenvolvimento , Sideróforos/metabolismo
20.
Se Pu ; 38(8): 923-928, 2020 Aug 08.
Artigo em Chinês | MEDLINE | ID: mdl-34213184

RESUMO

Using o-phthalaldehyde (OPA) as the derivatization reagent, a precolumn derivatized -high performance liquid chromatography (HPLC) method was developed for the simultaneous determination of amino acid neurotransmitters taurine (Tau), glutamic acid (Glu), glycine(Gly), and γ -aminobutyric acid (γ-GABA), as well as the monoamine neurotransmitter dopamine (DA), in serum samples. The samples and ethanol were mixed at a volume ratio of 1:2 (v/v) for protein precipitation. After centrifugation, the supernatant was withdrawn and blown to dryness using nitrogen. The residue was pre-column derivatized with OPA, and the derivatized product was isolated by gradient elution ona Luna 5u C18 column (250 mm×4.6 mm, 5 µm). Under the optimal experimental conditions, the five neurotransmitters showed good linearities (r2 ≥ 0.9866). The limits of detection were between 0.10 and 0.40 µmol/L. The spiked recoveries at different spiked levels were 87.57%-115.31%, and the RSDs were below 7.80%. This method is simple, sensitive, and it can be promised for the simultaneous detection of amino acid and monoamine neurotransmitters.


Assuntos
Aminoácidos , Neurotransmissores , Aminoácidos/sangue , Cromatografia Líquida de Alta Pressão , Humanos , Neurotransmissores/sangue , o-Ftalaldeído
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