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1.
Microvasc Res ; 139: 104252, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34520772

RESUMO

Soluble fms-like tyrosine kinase-1 (sFlt-1), a circulating antiangiogenic protein, is involved in the pathogenesis of atherosclerosis (AS), and the underlying mechanism is still unclear. Here, we attempted to investigate the mechanism of action of sFlt-1 in AS. Human umbilical vein endothelial cells (HUVECs) were treated with oxidized low density lipoprotein (ox-LDL) to induce cell injury. ox-LDL treatment increased LC3-II/LC3-I ratio, Beclin-1 expression and GFP-LC3 puncta in HUVECs, suggesting that ox-LDL may induce autophagic flux impairment in HUVECs. ox-LDL-treated HUVECs displayed a decrease of sFlt-1 levels. Moreover, ox-LDL treatment reduced cell proliferation and elevated apoptosis in HUVECs, which was abrogated by sFlt-1 overexpression. Up-regulation of sFlt-1 repressed the activity of PI3K/AKT/mTOR signaling pathway and enhanced autophagy in HUVECs following ox-LDL treatment. Additionally, sFlt-1 overexpression-mediated increase of autophagy in ox-LDL-treated HUVECs was abolished by 3-methyladenine (autophagy inhibitor). 3-methyladenine abrogated the impact of sFlt-1 overexpression on proliferation and apoptosis in ox-LDL-treated HUVECs. This work confirmed that overexpression of sFlt-1 activated autophagy by repressing PI3K/Akt/mTOR signaling pathway, and thus alleviated ox-LDL-induced injury of HUVECs. Therefore, this study suggests that sFlt-1 may be a potential target for AS treatment.

2.
Bioresour Technol ; 343: 126160, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34678447

RESUMO

As an energy-efficient and eco-friendly sludge treatment process, two-stage anaerobic digestion (AD) is widely employed to recovery biomass energy from waste sludge. However, the effect of primary and secondary sludge for two-stage AD was not clear. In this study, two-stage AD of mixed sludge in different volume ratio was investigated. The maximum cumulative H2 yield (100.5 ml) and CH4 yield (2643.6 ml) were obtained in volume ratio of 1:3 (primary sludge: secondary sludge). In two-phase AD, mixed sludge could induce positive effect on both organics releasing in extracellular polymeric substances (EPS) and the utilization of volatile fatty acids (VFAs). By investigating the compositional characteristics of dissolved organic matters (DOM) through excitation-emission matrix (EEM) coupling with fluorescence regional integration (FRI), it revealed more degradable substances utilization in mixture of sludge. Results from this work suggest that two-phase AD with mixed sludge is efficient for renewable energy recovery.


Assuntos
Matriz Extracelular de Substâncias Poliméricas , Esgotos , Anaerobiose , Espectrometria de Fluorescência
3.
J Exp Bot ; 2021 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-34727176

RESUMO

Vegetable oils are indispensable nutritional components of human diet as well as important raw materials for a variety of industrial applications such as pharmaceuticals, cosmetics, oleochemicals and biofuels. The oil plant genomes are highly diverse, and the genetic variation leads to the diversity in oil biosynthesis and accumulation along with agronomic traits. This review discusses the plant oil biosynthetic pathways, the current state of genome assembly, the polyploidy and asymmetric evolution genomes of oil plants and their wild relatives, and the research progress of pan-genomics in oil plants. The availability of complete high-resolution genomes and pangenomes has enabled the identification of structural variations in the genomes that are associated with the diversity of agronomic and environment fitness traits. These and more future genomes also provide powerful tools to understand crop evolution and to harvest the rich natural variations to improve oil crops for enhanced productivity, oil quality, and adaptability to changing environments.

4.
Front Oncol ; 11: 778068, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34737969
5.
iScience ; 24(11): 103240, 2021 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-34746704

RESUMO

Intracellular signaling dynamics play fundamental roles in cell biology. Precise modulation of the amplitude, duration, and frequency of signaling activation will be a powerful approach to investigate molecular mechanisms as well as to engineer signaling to control cell behaviors. Here, we showed a practical approach to achieve precise amplitude modulation (AM), frequency modulation (FM), and duration modulation (DM) of MAP kinase activation. Alternating current (AC) electrical stimulation induced synchronized ERK activation. Amplitude and duration of ERK activation were controlled by varying stimulation strength and duration. ERK activation frequencies were arbitrarily modulated with trains of short AC applications with accurately defined intervals. Significantly, ERK dynamics coded by well-designed AC can rewire PC12 cell fate independent of growth factors. This technique can be used to synchronize and modulate ERK activation dynamics, thus would offer a practical way to control cell behaviors in vivo without the use of biochemical agents or genetic manipulation.

6.
Chem Pharm Bull (Tokyo) ; 69(11): 1104-1109, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34719593

RESUMO

In this study, a series of alkyl diamine linked bivalent ß-carbolines was synthesized and evaluated as antitumor agent. The results demonstrated that most compounds displayed good antiproliferative activities with IC50 value lower than 10 µM against a panel of human tumor cell lines, and compound 8 was found to be the most potent antiproliferative agent with IC50 value of 1.39, 1.96, 1.42, 1.49, 1.32, 1.96 and 1.63 µM against human breast cancer cell line (MCF-7), human adenocarcinoma cell line (769-P), human malighant melanoma cell line (A375), human ovarian cancer cell line (SK-OV-3), human colon carcinoma cell line (HCT-116), human gastric cancer cell line (BGC-823) and human esophageal squamous carcinoma cell line (Eca-109), respectively. Further investigations on mechanism of action of this class of compound demonstrated that the representative compound 8 inhibited colorectal cancer growth through inducing autophagy.

7.
Nucleic Acids Res ; 2021 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-34788860

RESUMO

8-Oxo-7,8-dihydro-2'-deoxyguanosine (OG), one of the most common oxidative DNA damages, causes genome instability and is associated with cancer, neurological diseases and aging. In addition, OG and its repair intermediates can regulate gene transcription, and thus play a role in sensing cellular oxidative stress. However, the lack of methods to precisely map OG has hindered the study of its biological roles. Here, we developed a single-nucleotide resolution OG-sequencing method, named CLAPS-seq (Chemical Labeling And Polymerase Stalling Sequencing), to measure the genome-wide distribution of both exogenous and endogenous OGs with high specificity. Our data identified decreased OG occurrence at G-quadruplexes (G4s), in association with underrepresentation of OGs in promoters which have high GC content. Furthermore, we discovered that potential quadruplex sequences (PQSs) were hotspots of OGs, implying a role of non-G4-PQSs in OG-mediated oxidative stress response.

8.
J Environ Manage ; 302(Pt B): 114095, 2021 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-34775333

RESUMO

Microalgae are one of the promising sources for renewable energy production, and the light intensity variation can affect the biofuel generation and carbon assimilation of mixotrophic microalgae. To reveal the response of carbon assimilation to light intensity, the effect of light intensity on the carbon source metabolism of Chlorella vulgaris under mixotrophic cultivation was investigated in this study. Moreover, the optimal carbon source composition for mixotrophic microalgae cultivation was evaluated using bicarbonate (HCO3-) and carbonate (CO32-) as inorganic carbon sources, and glucose and acetate as organic carbon sources. The optimal light intensity for Chlorella vulgaris growth was at the range of 8000-12000 lux. For the accumulation of biochemical components, low light intensity was beneficial to protein accumulation, and high light intensity was advantageous for carbohydrate and lipid accumulation. With HCO3- and glucose, the maximum lipid content reached 37.0% at a light intensity of 12000 lux. The citrate synthase activity was negatively correlated with light intensity, showing an opposite trend to biomass production. High light intensity had a positive impact on Rubisco expression, which promoted the microalgae growth and carbon fixing. The energy produced by heterotrophic metabolic activities increased at low light intensity, and the enhancement of biomass production with high light intensity was mainly caused by the improved photoreaction efficiency during the mixotrophic cultivation.

9.
J Agric Food Chem ; 69(47): 14215-14221, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34786944

RESUMO

l-Ascorbic acid-2-phosphate (AsA-2P) is stable in aqueous solution and at high temperatures and is widely used in foods, pharmaceuticals, cosmetics, and fodders; however, practical application of enzymatic synthesis methods to promote industrial-scale production of AsA-2P remains a major challenge. In this study, we enhanced the phosphorylation efficiency of Pseudomonas aeruginosa acid phosphatase (APase; EC 3.1.3.2) for AsA-2P production via protein engineering. Among the mutants obtained, we selected the most efficient mutant (Var5; G125E/D135T/S136N), which exhibited an increased kcat of 18.6 s-1 and a Km for AsA of 223.9 mM. In addition, Var5 exhibited a maximum enzyme activity of 2080.4 U/L after 10 h of fermentation, which was 80% higher than the wild-type enzyme. Furthermore, under optimal conditions, Var5 showed a maximal conversion of 48.6% and achieved a final AsA-2P titer of 61.5 g/L at 8 h, which is considerably higher than that reported for other similar biocatalytic approaches. These findings demonstrate the potential of this method for the large-scale production of AsA-2P.

10.
Sci Rep ; 11(1): 22947, 2021 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-34824313

RESUMO

Applied Current Thermoacoustic Imaging (ACTAI) is a new imaging method which combines electromagnetic excitation with ultrasound imaging, and takes ultrasonic signal as medium and biological tissue conductivity as detection target. Taking the high contrast advantage of Electrical Impedance Tomography (EIT) and high resolution advantage of ultrasound imaging, ACTAI has broad application prospects in the field of biomedical imaging. Although ACTAI has high excitation efficiency and strong detectable Signal-to-Noise Ratio, yet while under low frequency electromagnetic excitation, it is still a big challenge to reconstruct a high-resolution image of target conductivity. This paper proposes a new method for reconstructing conductivity based on Generative Adversarial Network, and it consists of three main steps: firstly, use Wiener filtering deconvolution to restore the electrical signal output by the ultrasonic probe to a real acoustic signal. Then obtain the initial acoustic source image with filtered backprojection technology. Finally, match the conductivity image with the initial sound source image, which are used as training samples for generating the adversarial network to establish a deep learning model for conductivity reconstruction. After theoretical analysis and simulation research, it is found that by introducing machine learning, the new method can dig out the inverse problem solving model contained in the data, which further reconstruct a high-resolution conductivity image and has strong anti-interference characteristics. The new method provides a new way to solve the problem of conductivity reconstruction in Applied Current Thermoacoustic Imaging.

11.
Nat Commun ; 12(1): 6886, 2021 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-34824227

RESUMO

Microbial populations are a promising model for achieving microbial cooperation to produce valuable chemicals. However, regulating the phenotypic structure of microbial populations remains challenging. In this study, a programmed lysis system (PLS) is developed to reprogram microbial cooperation to enhance chemical production. First, a colicin M -based lysis unit is constructed to lyse Escherichia coli. Then, a programmed switch, based on proteases, is designed to regulate the effective lysis unit time. Next, a PLS is constructed for chemical production by combining the lysis unit with a programmed switch. As a result, poly (lactate-co-3-hydroxybutyrate) production is switched from PLH synthesis to PLH release, and the content of free PLH is increased by 283%. Furthermore, butyrate production with E. coli consortia is switched from E. coli BUT003 to E. coli BUT004, thereby increasing butyrate production to 41.61 g/L. These results indicate the applicability of engineered microbial populations for improving the metabolic division of labor to increase the efficiency of microbial cell factories.

12.
Int J Mol Sci ; 22(21)2021 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-34768943

RESUMO

As a metabolic organ, adipose tissue plays an important role in regulating metabolism. In adults, most adipose tissue is white adipose tissue (WAT), and excessive expansion of WAT will lead to obesity. It is worth noting that exercise can reduce the fat mass. There is also a lot of evidence that exercise can promote the browning of WAT, which is beneficial for metabolic homeostasis. Multiple factors, including reactive oxygen species (ROS), metabolites, nervous system, exerkines and lipolysis can facilitate exercise-mediated browning of WAT. In this review, the roles and the underlying mechanisms of exercise-mediated browning of WAT are summarized. The effects of different styles of exercise on the browning of WAT are also discussed, with the aim to propose better exercise strategies to enhance exercise-mediated browning of WAT, so as to promote metabolic health. Finally, the different reactivity of WAT at different anatomical sites to exercise-mediated browning is reviewed, which may provide potential suggestion for people with different fat loss needs.

13.
Opt Express ; 29(24): 39777-39787, 2021 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-34809334

RESUMO

We present a novel and effective approach for designing and analyzing graphene metasurface-based terahertz absorbers with the desired central frequency and fractional bandwidth. Narrowband and broadband absorbers are designed using the same configuration with a single-layer of graphene ribbons deposited on a metal-backed dielectric film. An analytical circuit model derived for the graphene array applies the impedance matching concept to realize the desired terahertz absorber. Absorbers with a fractional bandwidth ranging from 10-100% are realized at the 1-THz central frequency. The results show excellent agreement with those calculated using full-wave numerical simulations. The proposed method is promising for terahertz imaging, sensing, and filtering applications.

14.
Rice (N Y) ; 14(1): 98, 2021 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-34825994

RESUMO

Cold tolerance at the bud burst stage (CTB) is a key trait for direct-seeded rice. Although quantitative trait loci (QTL) affecting CTB in rice have been mapped using traditional linkage mapping and genome-wide association study (GWAS) methods, the underlying genes remain unknown. In this study, we evaluated the CTB phenotype of 339 cultivars in the Rice Diversity Panel II (RDP II) collection. GWAS identified four QTLs associated with CTB (qCTBs), distributed on chromosomes 1-3. Among them, qCTB-1-1 overlaps with Osa-miR319b, a known cold tolerance micro RNA gene. The other three qCTBs have not been reported. In addition, we characterised the candidate gene OsRab11C1 for qCTB-1-2 that encodes a Rab protein belonging to the small GTP-binding protein family. Overexpression of OsRab11C1 significantly reduced CTB, while gene knockout elevated CTB as well as cold tolerance at the seedling stage, suggesting that OsRab11C1 negatively regulates rice cold tolerance. Molecular analysis revealed that OsRab11C1 modulates cold tolerance by suppressing the abscisic acid signalling pathway and proline biosynthesis. Using RDP II and GWAS, we identified four qCTBs that are involved in CTB and determined the function of the candidate gene OsRab11C1 in cold tolerance. Our results demonstrate that OsRab11C1 is a negative regulator of cold tolerance and knocking out of the gene by genome-editing may provide enhanced cold tolerance in rice.

15.
J Mol Model ; 27(12): 363, 2021 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-34825997

RESUMO

The study of the reaction between plutonium and nitrogen is helpful in further understanding the interaction between plutonium and air molecules. Currently, there is no research on the microscopic reaction mechanism of plutonium nitridation reactions. Therefore, the microscopic mechanism of the Pu with N2 gas phase reaction is explored in this study, based on density functional theory (DFT) using different basis functions. In this paper, the geometry of stationary points on the potential energy surface is optimized. In addition, the transition states are verified by frequency analysis and intrinsic reaction coordination (IRC). Finally, we obtained the reaction potential energy curve and micro reaction pathways. Analysis of the reaction mechanism shows that the reaction of Pu with N2 has two pathways. Pathway 1 (Pu + N2 → R1 → TS1 → PuN2) has a T-shaped transition state and pathway 2 (Pu + N2 → R2 → TS2 → PuN + N) has an L-shaped transition state. Both transition states have only one imaginary frequency. According to the comparison of the energy at each stagnation point along the two pathways, and the heat energy emitted by the two reaction paths, we found that pathway 1 is the main reaction pathway. The nature of Pu-N bonding evolution along the pathways was studied by atoms in molecules (AIM) and electron localization function (ELF) topological approaches. In order to analyze the role of the plutonium atom 5f orbital in the reaction, the variation in density state along the pathways was measured. Results show that the 5f orbital mainly contributes to the formation of Pu-N bonds, and the influence of temperature on the reaction rate is revealed by calculating the rate constants of the two reaction pathways.

16.
Front Oncol ; 11: 700204, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34722248

RESUMO

Objective: To confirm the diagnostic performance of computed tomography (CT)-based texture analysis (CTTA) and magnetic resonance imaging (MRI)-based texture analysis for grading cartilaginous tumors in long bones and to compare these findings to radiological features. Materials and Methods: Twenty-nine patients with enchondromas, 20 with low-grade chondrosarcomas and 16 with high-grade chondrosarcomas were included retrospectively. Clinical and radiological information and 9 histogram features extracted from CT, T1WI, and T2WI were evaluated. Binary logistic regression analysis was performed to determine predictive factors for grading cartilaginous tumors and to establish diagnostic models. Another 26 patients were included to validate each model. Receiver operating characteristic (ROC) curves were generated, and accuracy rate, sensitivity, specificity and positive/negative predictive values (PPV/NPV) were calculated. Results: On imaging, endosteal scalloping, cortical destruction and calcification shape were predictive for grading cartilaginous tumors. For texture analysis, variance, mean, perc.01%, perc.10%, perc.99% and kurtosis were extracted after multivariate analysis. To differentiate benign cartilaginous tumors from low-grade chondrosarcomas, the imaging features model reached the highest accuracy rate (83.7%) and AUC (0.841), with a sensitivity of 75% and specificity of 93.1%. The CTTA feature model best distinguished low-grade and high-grade chondrosarcomas, with accuracies of 71.9%, and 80% in the training and validation groups, respectively; T1-TA and T2-TA could not distinguish them well. We found that the imaging feature model best differentiated benign and malignant cartilaginous tumors, with an accuracy rate of 89.2%, followed by the T1-TA feature model (80.4%). Conclusions: The imaging feature model and CTTA- or MRI-based texture analysis have the potential to differentiate cartilaginous tumors in long bones by grade. MRI-based texture analysis failed to grade chondrosarcomas.

17.
Toxics ; 9(11)2021 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-34822690

RESUMO

Chemotherapy-induced peripheral neuropathy (CIPN) is widely recognized as a potentially severe toxicity that often leads to dose reduction or discontinuation of cancer treatment. Symptoms may persist despite discontinuation of chemotherapy and quality of life can be severely compromised. The clinical symptoms of CIPN, and the cellular and molecular targets involved in CIPN, are just as diverse as the wide variety of anticancer agents that cause peripheral neurotoxicity. There is an urgent need for extensive molecular and functional investigations aimed at understanding the mechanisms of CIPN. Furthermore, a reliable human cell culture system that recapitulates the diversity of neuronal modalities found in vivo and the pathophysiological changes that underlie CIPN would serve to advance the understanding of the pathogenesis of CIPN. The demonstration of experimental reproducibility in a human peripheral neuronal cell system will increase confidence that such an in vitro model is clinically useful, ultimately resulting in deeper exploration for the prevention and treatment of CIPN. Herein, we review current in vitro models with a focus on key characteristics and attributes desirable for an ideal human cell culture model relevant for CIPN investigations.

18.
Zootaxa ; 5027(3): 429-437, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34811161

RESUMO

A new species of the genus Lemaireia Nssig Holloway, 1988 (Lepidoptera: Saturniidae: Saturniinae: Saturniini), L. daparo sp. n., is described from evergreen broad-leaf forests in Panzhihua (Sichuan), Qujing (Yunnan) and Dali (Yunnan) of China. The new species resembles L. luteopeplus aureopeplus Nssig Holloway, 1988 and L. hainana Nssig Wang, 2006 from China, but can be easily separated from them by the male genitalia. In addition, the genus Lemaireia is reported here for the first time from Sichuan Province, and now its distribution range reached the northeastern extreme point. The habitus, diagnostic characters and distribution map of the three species of the genus Lemaireia from China are provided. A list of all Lemaireia species presently known worldwide is also given.


Assuntos
Lepidópteros , Mariposas , Distribuição Animal , Animais , China , Genitália Masculina , Folhas de Planta
19.
J Org Chem ; 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34780194

RESUMO

The Catellani reaction provides an efficient synthetic approach to polyfunctionalized arenes. However, the selective ortho-arylating reagents employed in these reactions have been strictly limited to activated bromoarenes. As demonstrated in this work, aryl diazonium salts bearing both electron-donating and electron-withdrawing substituents, after in situ transformations with KI into the corresponding iodoarenes, were efficient arylating reagents for Catellani type ortho-arylation approaches.

20.
Fish Shellfish Immunol ; 120: 180-189, 2021 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-34838985

RESUMO

The interplay between virus and host has been one of the hot spot in virology, and it is also the important aspect of revealing the mechanism of virus infection. Increasing studies revealed that several key molecules took part in the process of virus-host interaction. White spot syndrome virus (WSSV) has been proved to affect several physiological processes of the host cells, especially apoptosis. While the relationship between them still remains unclear. In this study, a IFI27 gene (LvIFI27) of Litopenaeus vannamei was cloned. It is indicated that LvIFI27 was induced upon endoplasmic reticulum (ER)-stress and unfolded protein response activator Thapsigargin. Unlike human IFI27 locating to mitochondria, LvIFI27 lied to ER, and was involved in cell apoptosis process. Moreover, results of cumulative mortality analysis showed that LvIFI27 might contributed to WSSV proliferation by promoting apoptosis during the process of viral infection. Findings in this study enriched our understanding of the relationship between WSSV infection and ER-stress mediated apoptosis.

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