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1.
J Hazard Mater ; 421: 126628, 2022 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-34343879

RESUMO

Electroreduction of nitrate (NO3-) to value-added ammonia (NH3) provides an alternative to NH3 production industry and remediation of NO3--containing wastewater. This study reports a series of Cu-Ni catalysts with component-controllable CuxNiy nanoparticles encapsulated in N-doped carbon film (CuxNiy/NC), and disclosure of the associated mechanism for NO3- reduction reaction (NO3-RR). Cu0.43Ni0.57/NC achieves a better NO3--N removal proportion of 89% in comparison with the reference catalysts, including Cu/NC (73%) and CuxNiy/NC with other compositions (Cu0.79Ni0.21/NC, 83%; Cu0.26Ni0.74/NC, 62%; Ni/NC, 20%). The experimental results and density functional theory calculations demonstrate that the lowered energy barriers of *NO2-to-*NO derived from appropriate Ni atom alloying plays a key role in the enhanced catalytic activity. Auxiliary porous substrate further contributes to the exposure of active sites and the durability of catalyst structure. These findings offer a mechanistic understanding of catalyst structure on the NO3-RR activity and valuable insights toward rational design of other catalysts for enhanced NO3-RR.

2.
ACS Omega ; 6(43): 28587-28597, 2021 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-34746554

RESUMO

To reduce the cost of synthetic organic corrosion inhibitors in corrosion protection, dye wastewater exhibiting a synergistic effect is used with organic corrosion inhibitors to reduce the amount of high-cost molecules. The corrosion inhibition effects of the cationic dye methylene blue (MB) and the anionic dye methyl orange (MO) are tested. The test methods include electrochemical methods, weight-loss tests, and so on. MB exhibits better performance on the tested steel, with the anticorrosion efficiency reaching as high as 75.40%, which is chosen as an additive for organic corrosion inhibitors. After that, an organic inhibitor decamethylene bis-pyridinium dibromide (DBP) is selected for compounding with MB, and the corrosion inhibition effect under different ratios is tested. Similar effects of the compound inhibitor to the pristine sample are obtained at a ratio of MB/DBP = 6:4. In addition to experiments, theoretical calculations have also confirmed that the addition of dye molecules can inhibit corrosion. This research not only provides a way to reuse dye wastewater but also proposes measures to reduce the cost of organic corrosion inhibitors and, at the same time, provides new ideas for environmental protection and metal protection.

3.
Insects ; 12(11)2021 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-34821783

RESUMO

Insect galls are the abnormal growth of plant tissues induced by a wide variety of galling insects and characterized by high concentrations of auxins and cytokinins. It remains unclear whether the auxins and cytokinins affect the bacterial community structure of insect galls. We determined the concentrations of indoleacetic acid (IAA) as an example of auxin, trans-zeatin riboside (tZR) and isopentenyladenine (iP) as cytokinins in Lithosaphonecrus arcoverticus (Hymenoptera: Cynipidae) galls and the galled twigs of Lithocarpus glaber (Fagaceae) using liquid chromatography-tandem mass spectrometry. Moreover, for the first time, we compared the bacterial community structure of L. arcoverticus galls and galled twigs by high-throughput sequencing, and calculated the Spearman correlation and associated degree of significance between the IAA, tZR and iP concentrations and the bacterial community structure. Our results indicated the concentrations of IAA, tZR and iP were higher in L. arcoverticus galls than in galled twigs, and positively correlated with the bacterial community structure of L. arcoverticus galls. We suggest the high concentrations of IAA, tZR and iP may affect the bacterial community structure of L. arcoverticus galls.

4.
J Agric Food Chem ; 69(45): 13568-13577, 2021 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-34730357

RESUMO

To improve the reactivity and enrich the functionality of lignin for valorization, kraft lignin was depolymerized and demethylated via cleaving aryl and alkyl ether bonds in acidic lithium bromide trihydrate (∼60% LiBr aqueous solution). It was found that the cleavage of the ether bonds followed the order of ß-O-4 ether > aryl alkyl ether in phenylcoumaran > dialkyl ether in resinol > methoxyl (MeO). The depolymerization via ß-O-4 cleavage occurred under mild conditions (e.g., <0.5 M HCl at 110 °C), while sufficient demethylation of the lignin needed harsher conditions (>1.5 M HCl). Both depolymerization and demethylation generated new aromatic hydroxyl (ArOH). With 2.4 M HCl, MeO content dropped from 4.85 to 0.95 mmol/g lignin, and ArOH content increased from 2.78 to 5.09 mmol/g lignin. The depolymerized and demethylated kraft lignin showed excellent antioxidant activity and Cr(VI)-scavenging capacity, compared with original kraft lignin and tannins.


Assuntos
Antioxidantes , Lignina , Desmetilação , Éteres , Lignina/metabolismo
5.
Front Bioeng Biotechnol ; 9: 778332, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34805125

RESUMO

In this study, seven 316L stainless steel (316L SS) bulks with different angles (0°, 15°, 30°, 45°, 60°, 75°, and 90°) relative to a build substrate were built via selective laser melting (SLM). The influences of different angles on the metallography, microstructure evolution, tensile properties, and corrosion resistance of 316L SS were studied. The 0° sample showed the morphology of corrugated columnar grains, while the 90° sample exhibited equiaxed grains but with a strong <101> texture. The 60° sample had a good strength and plasticity: the tensile strength with 708 MPa, the yield strength with 588 MPa, and the elongation with 54.51%. The dislocation strengthening and grain refinement play a vital role in the mechanical properties for different anisotropy of the SLM-fabricated 316L SS. The 90° sample had greater toughness and corrosion resistance, owing to the higher volume fraction of low-angle grain boundaries and finer grains.

6.
ChemSusChem ; 2021 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-34796684

RESUMO

10-Hydroxy-2-decenoic acid (10-HDA) is a terminal hydroxylated medium-chain α, ß-unsaturated carboxylic acid that performs various unique physiological activities and has a wide market value. Therefore, development of an environmentally friendly, safe, and high-efficiency route to synthesize 10-HDA is required . Here, we modified the ß-oxidation pathway of Escherichia coli and rationally designed P450 terminal hydroxylase (CYP153A33-CPR BM3 ) to synthesize 10-HDA using decanoic acid as a substrate via two-step whole-cell catalysis. We analysed different homologues of FadDs, FadEs, and YdiIs in the first step of the conversion of decanoic acid to trans- 2-decenoic acid. In the second step, CYP153A33 (M228L)-CPR BM3 efficiently catalysed the conversion of trans -2-decenoic acid to 10-HDA. Finally, we obtained 217 mg L -1 10-HDA with 500 mg L -1 decanoic acid. Our study provides a strategy for biosynthesis of 10-HDA and other α, ß-unsaturated carboxylic acid derivatives from specific fatty acids.

7.
Brain Res ; 1774: 147723, 2021 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-34780748

RESUMO

Epilepsy is a common chronic neurological disorder worldwide, but its entire pathology remains unknown. The purpose of this study was to explore the antiepileptic effect of baicalin (BAL), the main bioactive component of scutellaria. We isolated astrocytes from neonatal rats and astrocytes were identified by glial fibrillary acidic protein (GFAP) immunostaining. The viability and phenotype of astrocytes were determined by Cell Counting Kit-8 (CCK-8) and immunofluorescence staining, respectively. For investigating the effect of BAL on the autophagy in A1 astrocytes treated PC12 cells, expression of light chain 3B (LC3-B) and sequestosome 1 (P62) was analyzed by immunofluorescence staining and apoptosis by acridine orange/ethidium bromide (AO/EB) staining, respectively. For animal experiments, pentylenetetrazol (PTZ)-induced epileptic model was used to explore the antiepileptic effect of BAL. The results showed that BAL reduced lipopolysaccharide (LPS)-induced complement C3 (C3, a marker of A1 astrocytes) + A1 cells and decreased autophagy and apoptosis in PC12 cells. Further findings showed seizure grade and latency were positively correlated with GFAP+/C3 + A1 cells' infiltration in interstitial astrocytes. After BAL treatment, epileptogenesis was ameliorated with decreased A1 astrocytes in the brain and improved behavioral performance. The enzyme-linked immunosorbent assay (ELISA) showed that the levels of interleukin-1α (IL-1α) and tumor necrosis factor-α (TNF-α) were reduced in the cerebral interstitial site in the BAL group compared to the PTZ group. Western blotting analysis showed that BAL treatment reduced expression of C3, inward rectifier potassium channel Kir4.1, aquaporin-4 (AQP4) in the frontal cortex and Caspase-3, BCL2-associated X protein (Bax) in the hippocampus. In conclusion, these findings suggest that BAL can prevents cognitive and emotional disorders and has antiepileptic effects in rats, which may be associated with suppresses neuron autophagy and apoptosis in the hippocampus via regulate astrocyte phenotypes.

8.
Biotechnol J ; : e2100408, 2021 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-34705337

RESUMO

BACKGROUND: As an important farm animal, pig functional genomic study can help understand the molecular mechanism related to the key economic traits of pig, such as growth, reproduction, or disease. The genome-scale library based on clustered regularly interspaced short palindromic repeat (CRISPR)/CRISPR-associated endonuclease Cas9 (Cas9) system facilitates discovery of key genes involved in a specific function or phenotype, allowing for an effective "phenotype-to-genotype" strategy for functional genomic study. METHODS AND RESULTS: We designed and constructed a pig genome-scale CRISPR/Cas9 knockout library targeting 16,888 genes with 970,001 unique sgRNAs. The library is a single-vector system including both Cas9 and sgRNA, and packaged into lentivirus for an easy cell delivery for screening. To establish a screening method in pig cells, we used diphtheria toxin (DT)-induced cell death as a model to screen the host genes critical for DT toxicity in pig PK-15 cells. After lentiviral transduction and two sequential screening with DT treatment, the highest-ranking candidates we identified were previously validated genes, HBEGF, DPH1, DPH2, DPH3, DPH5, DNAJC24, and ZBTB17, which are DT receptor and the key factors involved in biosynthesis of diphthamide, the target of DT action. The function and gene essentiality of candidates were further confirmed by gene knockout and DT toxicity assay in PK-15 cells. CONCLUSIONS: Our CRISPR knockout library targeting pig whole genome establishes a promising platform for pig functional genomic analysis.

9.
Front Oncol ; 11: 720814, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34676163

RESUMO

Arsenic trioxide (ATO) has been used to treat acute promyelocytic leukemia. However, it is not effective in treating solid tumors such as colorectal cancer. We have previously reported that polyploid giant cancer cells (PGCCs) exhibiting the characteristics of cancer stem cells can be generated by various inducers. In this study, ATO was used to induce the formation of PGCCs in LoVo and Hct116 colon cancer cell lines. The migration, invasion, and proliferation abilities of colon cancer cells with and without ATO treatment were assessed by wound-healing, transwell, and plate colony formation assays. The expression of epithelial to mesenchymal transition-related proteins and erythroid differentiation-related proteins in colon cancer cells was further evaluated by western blot and immunocytochemical assays. LoVo and Hct116 cells were transfected with a eukaryotic expression vector for green fluorescent protein (GFP), red fluorescent protein (RFP), H2B-GFP, and H2B-mCherry to study PGCCs formation via cell fusion. WB and ICC assays were performed to assess the expression of cell fusion-related proteins. MG132, small interfering RNA-glial cell missing 1 (GCM1), and chromatin immunoprecipitation-polymerase chain reaction assays were performed to study the role of GCM1/syncytin-1-mediated cell fusion. Clinically, the significance of cell fusion-related proteins and erythroid differentiation-related proteins expression in human colorectal cancer tissues was evaluated. Results of our study showed that ATO induced the formation of PGCCs, and the daughter cells derived from PGCCs gained a mesenchymal phenotype and exhibited strong migration, invasion, and proliferation abilities. PGCCs also produced embryonic hemoglobin-delta and -zeta with strong oxygen-binding ability and erythroid differentiation-related proteins after ATO treatment. In addition, cell fusion was observed during the formation of PGCCs, indicated by the presence of yellow fluorescence via the GCM1/syncytin-1 signaling pathway. Clinically, the expression of cell fusion-related and erythroid differentiation-related proteins gradually increased with the progression of human colorectal cancer tissues. In conclusion, ATO can promote tumor progression by inducing the formation of PGCCs via GCM1/syncytin-1-mediated cell fusion. PGCCs can produce daughter cells with high invasion and migration abilities and embryonic hemoglobin with strong oxygen binding ability, promoting survival of tumor cells in a hypoxic microenvironment.

10.
Int J Gen Med ; 14: 7065-7076, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34707398

RESUMO

Background: Severe trauma and burns accompanied by sepsis are associated with high morbidity and mortality. Little is known about the transcriptional similarity between trauma, burns, sepsis, and systemic inflammatory response syndrome (SIRS). Uncovering key genes and molecular networks is critical to understanding the biology of disease. Conventional analysis of gene changes (fold change) analysis is difficult for time-serial data such as post-injury blood transcriptome. Methods: Weighted gene co-expression network analysis (WGCNA) was applied to the trauma dataset to identify modules and hub genes. Module stability was tested by half sampling. Module preservations of burns, sepsis, and SIRS were calculated using trauma as reference. Module functional enrichment was analyzed in gProfiler server. Candidate drugs were screened using Connectivity Map based on hub genes. The modules were visualized in Cytoscape. Results: Seventeen modules were identified. The modules were robust to the exclusion of half the sample. They were involved in lymphocyte and platelet activation, erythrocyte differentiation, cell cycle, translation, and interferon signaling. In addition, highly connected hub genes were identified in each module, such as GUCY1B1, BCL11B, HMMR, and CEACAM6. High BCL11B (M13) or low CEACAM6 (M27) expression indicates better survival prognosis in sepsis patients regardless of endotype class and age. Network preservation in burns, sepsis, and SIRS showed a general similarity between trauma and burns. M4, M5, M13, M16, M20, and M27 were significantly associated with injury time in trauma and burns. High M13 (T cell activation), low M15 (cell cycle), and low M27 (neutrophil activation) indicate better survival of sepsis patients, regardless of endotype class and age. Moreover, the modules can efficiently separate patients with different diseases. Some modules and hub genes have good prognostic performance in sepsis. Based on the hub genes of each module, six candidate drugs were screened. Conclusion: This study first compared the gene co-expression modules in trauma, burns, sepsis, and SIRS. The identified modules are useful for disease prognosis and drug discovery. BCL11B and CEACAM6 may be promising biomarkers for sepsis risk assessment.

11.
Phys Chem Chem Phys ; 23(38): 22035-22044, 2021 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-34570137

RESUMO

The electrocatalytic reduction of CO2 is considered an effective method to reduce CO2 emissions and achieve electrical/chemical energy conversion. It is crucial to determine the reaction mechanism so that the key reaction intermediates can be targeted and the overpotential lowered. The process involves the interaction with the electrode surface and with species, including the solvent, at the electrode-electrolyte interface, and it is therefore not easy to separate catalytic contributions of the electrode from those of the electrolyte. We have used density functional theory-based molecular dynamics to calculate the Gibbs free energy of the proton and electron transfer reactions corresponding to each step in the electroreduction of CO2 to HCOOH in aqueous media. The results show thermodynamic pathways consistent with the mechanism proposed by Hori. Since electrodes are not included in this work, differences between the calculated results and the experimental observations can help determine the catalytic contribution of the electrode surface.

12.
Cell Discov ; 7(1): 84, 2021 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-34518515

RESUMO

IL6 is one of the most elevated cytokines during chimeric antigen receptor (CAR) T cell cytokine release syndrome (CRS), and IL6R blockade by Tocilizumab has successfully relieved the most life-threatening aspects of CRS in patients. In addition, latest studies demonstrated the essential role of IL1 in driving CART induced neurotoxicity in mouse models. Here we present a clinical investigation (ChiCTR2000032124; ChiCTR2000031868) of anti-CD19 and anti-BCMA CART (41BBζ) secreting an anti-IL6 scFv and IL1 receptor antagonist (IL1RA) in treating patients with hematologic malignancy. Our results revealed that IL6 and IL1B were maintained at low levels without significant elevation during CRS, rendering Tocilizumab dispensable. Moreover, treated patients did not show neurotoxicity during CRS and exhibited mild to moderate CRS. Notably, we observed high rate of complete response (CR) and significant CART expansion during treatment. In sum, we conclude that CART-secreting anti-IL6 scFv and IL1RA could self-neutralize IL6 storm and maintain low levels of IL1B during CART therapy to minimize IL6- and IL1-associated cytokine toxicity and neurotoxicity without impairing therapeutic efficacy.

13.
J Phys Chem Lett ; 12(37): 8924-8931, 2021 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-34499508

RESUMO

Electrode potential is the key factor for controlling electrocatalytic reactions at electrochemical interfaces, and moreover, it is also known that the pH and solutes (e.g., cations) of the solution have prominent effects on electrocatalysis. Understanding these effects requires microscopic information on the electrochemical interfaces, in which theoretical simulations can play an important role. This Perspective summarizes the recent progress in method development for modeling electrochemical interfaces, including different methods for describing the electrolytes at the interfaces and different schemes for charging up the electrode surfaces. In the final section, we provide an outlook for future development in modeling methods and their applications to electrocatalysis.

14.
Insects ; 12(8)2021 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-34442279

RESUMO

Phage WO was first characterized in Wolbachia, an obligate intracellular Rickettsiales known for its ability to regulate the reproduction of arthropod hosts. In this paper, we focus on the study of virus diversity in Andricus hakonensis and the development of highly effective primers. Based on the existing Wolbachia genome sequence, we designed primers (WO-TF and WO-TR) to amplify the full-length orf7 gene of phage WO. Surprisingly, sequencing results showed a high abundance of other phage WO groups in A. hakonensis, in addition to the four groups previously identified. The results also showed that A. hakonensis contained most of the known types of orf7 genes (I, III, IV, V and VI) and the level of diversity of harbored phage WO was very high. Therefore, we speculated that existing primers were not specific enough and that new primers for the detection of phage WO were needed. Based on the existing orf7 gene sequence, we designed specific detection primers (WO-SUF and WO-SUR). Sequencing results showed that the primers effectively amplified all known types of phage WO. In addition to amplifying most of the known sequences, we also detected some new genotypes in A. hakonensis using the new primers. Importantly, all phage WO groups could be efficiently detected. Combined with the results of previous studies, our results suggest that A. hakonensis contains the largest number of phage types (up to 36 types). This study is novel in that it provides practical molecular evidence supporting base deletions, in addition to gene mutations and genetic recombination, as an important cause of phage WO diversity.

15.
Front Mol Biosci ; 8: 716415, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34355022

RESUMO

Annexin A3 (ANXA3), also known as lipocortin III and placental anticoagulant protein III, has been reported to be dysregulated in tumor tissues and cancer cell lines, and harbors pronounced diagnostic and prognostic value for certain malignancies, such as breast, prostate, colorectal, lung and liver cancer. Aberrant expression of ANXA3 promotes tumor cell proliferation, invasion, metastasis, angiogenesis, and therapy resistance to multiple chemotherapeutic drugs including platinum-based agents, fluoropyrimidines, cyclophosphamide, doxorubicin, and docetaxel. Genetic alterations on the ANXA3 gene have also been reported to be associated with the propensity to form certain inherited, familial tumors. These diverse functions of ANXA3 in tumors collectively indicate that ANXA3 may serve as an attractive target for novel anticancer therapies and a powerful diagnostic and prognostic biomarker for early tumor detection and population risk screening. In this review, we dissect the role of ANXA3 in cancer in detail.

16.
Huan Jing Ke Xue ; 42(9): 4083-4094, 2021 Sep 08.
Artigo em Chinês | MEDLINE | ID: mdl-34414707

RESUMO

This study developed a two-stage statistical model (linear mixed effect (LME) model+geographical weight regression (GWR) model) to determine the spatio-temporal variation of PM2.5 concentrations in the Beijing-Tianjin-Hebei (BTH) region with full-coverage, high resolution, and high accuracy. The model employs multi-angle implementation of atmospheric correction aerosol optical depth (MAIAC AOD) data, with a 1 km spatial resolution, as the main predictor and meteorological data/land-use data as the auxiliary predictors. To determine the characteristics of heavy PM2.5 pollution in the BTH region, unique predictors such as AOD2 were also introduced into the two-stage model. The two-stage model was used to estimate the daily PM2.5 concentrations with a 1 km resolution. After being cross-validated against ground observations, the R2 of PM2.5 was found to be 0.94, with a slope value of 0.95 and RMSPE value of 13.14 µg·m-3. Compared to previous studies such as LME, the two-stage model has much higher accuracy, suitable for estimating PM2.5 concentrations. The PM2.5 concentration in the BTH region ranged from 0 to 89.89 µg·m-3 in 2017, with a mean value of 44.96 µg·m-3. The spatio-temporal variability of PM2.5 over the BTH region was significant, exhibiting high values over the southwestern plain, moderate values over the northeastern plain, and low values over the mountainous plateau. In terms of seasonal variation, PM2.5 concentrations were high in winter, low in summer, and moderate in spring and autumn. The estimated PM2.5 concentrations, with high spatio-temporal resolution, are useful for exposure assessments in epidemiological studies and identifying the spatio-temporal variation of pollution sources at a fine spatial scale. The results show that the locations of vital pollution sources over the severely polluted south-central Hebei piedmont plain may have changed since the implementation of the Air Pollution Prevention and Control Action Plan. This study could provide a scientific basis for the prevention and control of air pollution in the BHT region.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Pequim , Monitoramento Ambiental , Humanos , Material Particulado/análise
17.
Micromachines (Basel) ; 12(7)2021 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-34357234

RESUMO

Based on the conventional structure of traveling wave ultrasonic motor, a rotary ultrasonic motor with double-sided staggered teeth was proposed. Both sides of the stator could be used to actuate the rotors to rotate and output torque. Moreover, the staggered teeth in the stator could be dedicated to accommodating the piezoelectric ceramic chips. Under the excitation of two alternating voltages with a 90° phase difference, a traveling wave could be generated in the ring-like stator. Then, a rotary motion could be realized by means of the friction between the rotors and the driving teeth of the stator. The finite element method was adopted to analyze the motion trajectories of the driving tips. Moreover, the experimental results showed that the load-free maximum speed and maximum output torque of the prototype were 99 rpm and 0.19 N·m at a voltage of 150 Vp with a frequency of 28.25 kHz.

18.
Behav Neurol ; 2021: 9990375, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34447483

RESUMO

Background: Aß deposition abnormally in the mitochondria can damage the mitochondrial respiratory chain and activate the mitochondrial-mediated apoptosis pathway, resulting in AD-like symptoms. Objective: To observe the protective effects of Dendrobium nobile Lindl. alkaloids (DNLA) on Aß 25-35-induced oxidative stress and apoptosis in PC12 cells explore its possible protective mechanisms. Methods: PC12 cells were treated with DNLA with different concentrations (0.035 mg/L, 0.3 mg/L, and 3.5 mg/L) for 6 h, followed by administration with Aß 25-35 (10 µM) for 24 h. MTT assay and flow cytometer observe the effect of DNLA on Aß 25-35-induced cytotoxicity and apoptosis of PC12 cell. Based on the mitochondrial apoptosis pathway to study the antiapoptotic effect of DNLA on this model and its relationship with oxidative stress, flow cytometer detected the level of reactive oxygen species (ROS), and ELISA kits were used to detect superoxide dismutase activity (SOD) and glutathione (GSH) content in cells. The JC-1 fluorescent staining observed the effect of DNLA on the mitochondrial membrane potential (MMP) with inverted immunofluorescence microscopy. Western blot was used to detect the levels of mitochondrial apoptosis pathway-related protein and its major downstream proteins Bax, Bcl-2, cleaved-caspase-9, and cleaved-caspase-3. Results: DNLA can significantly improve the viability and apoptosis rate of PC12 cell damage induced by Aß 25-35. It also can restore the reduced intracellular ROS content and MMP, while SOD activity and GSH content increase significantly. The expression of apoptosis-related protein Bax, cleaved-caspase-9, and cleaved-caspase-3 decreased when the Bcl-2 protein expression was significantly increased. Conclusion: These findings suggest that it can significantly inhibit the apoptosis of PC12 cell damage induced by Aß 25-35. The mechanism may reduce the level of cellular oxidative stress and thus inhibit the mitochondrial-mediated apoptosis pathway.


Assuntos
Alcaloides , Dendrobium , Alcaloides/farmacologia , Animais , Apoptose , Estresse Oxidativo , Células PC12 , Ratos
19.
Front Microbiol ; 12: 694115, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34276627

RESUMO

The phage WO was characterized in Wolbachia, a strictly intracellular bacterium causing several reproductive alterations in its arthropod hosts. This study aimed to screen the presence of Wolbachia and phage WO in 15 gall wasp species from six provinces of southern China to investigate their diversity and prevalence patterns. A high incidence of Wolbachia infection was determined in the gall wasp species, with an infection rate of 86.7% (13/15). Moreover, seven species had double or multiple infections. All Wolbachia-infected gall wasp species were found to harbor phage WO. The gall wasp species infected with a single Wolbachia strain were found to harbor a single phage WO type. On the contrary, almost all species with double or multiple Wolbachia infections harbored a high level of phage WO diversity (ranging from three to 27 types). Six horizontal transfer events of phage WO in Wolbachia were found to be associated with gall wasps, which shared identical orf7 sequences among their respective accomplices. The transfer potentially took place through gall inducers and associated inquilines infected with or without Wolbachia. Furthermore, 10 putative recombination events were identified from Andricus hakonensis and Andricus sp2, which harbored multiple phage WO types, suggesting that intragenic recombination was the important evolutionary force, which effectively promoted the high level of phage WO diversity associated with gall wasps.

20.
ACS Omega ; 6(28): 18084-18098, 2021 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-34308042

RESUMO

Fault diagnosis technology of power transformers is essential for the stable operation of power systems. Fault diagnosis technology based on dissolved gas analysis (DGA) is one of the most commonly used methods. However, due to the lack of fault information, traditional DGA fault diagnosis techniques are difficult to meet increasing power demand in terms of accuracy and efficiency. To address this problem, this paper proposes a novel fault diagnosis model for oil-immersed transformers based on International Electrotechnical Commission (IEC) ratio methods and probabilistic neural network (PNN) optimized with the modified moth flame optimization algorithm (MMFO). PNN as a radial neural network has good utility and is often used in classification models, but its classification performance is easily affected by the smoothing factor (σ) of the hidden layer and is not stable. This paper addresses this issue using the MMFO to optimize the smoothing factor, which effectively improves the classification accuracy and robustness of PNN. The proposed method was validated by conducting the experiments with the real data collected from transformers. Experimental results show that the MMFO-PNN model improves the fault diagnosis accuracy rate from 70.65 to 99.04%, which is higher than other power transformer fault diagnosis models.

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