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1.
Opt Lett ; 49(19): 5587-5590, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39353012

RESUMO

A topological bound state in the continuum (TBIC) is a novel topological phase that has attracted significant attention. Different from conventional topological insulators (TIs), where boundary states reside within gaps, TBICs can support unconventional boundary states that remain isolated from the surrounding bulk states. In this work, we experimentally demonstrate multiple TBICs in photonic bilayer trimer lattices using femtosecond laser writing technology. By modulating the interlayer coupling between two trimer chains, we observe the emergence of two distinct types of TBICs. Moreover, we experimentally achieve the coexistence of in-gap topological states and TBICs and demonstrate the transformation between them. Our work unveils new insights into the flexible construction of TBICs, and this method can be easily applied to other one-dimensional topological structures, offering promising avenues for further research.

2.
Molecules ; 29(18)2024 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-39339495

RESUMO

Despite the fact that doping nanoparticles into insulating transformer oil has proven to be an effective method of enhancing its dielectric and electrical properties, it remains unclear how different types and surface conditions of nanoparticles may affect their dielectric and electrical properties. Therefore, the effect of doping various types of BN nanoparticles (nanosphere, nanotube, and nanosheet) in insulating mineral oil (MO) on the diffusion properties of water molecules and electrical properties across the BN/MO interface was investigated using molecular dynamics (MD) and Density Functional Theory (DFT) simulations. Our results show that different surface morphology and grafted functional groups in different types of BN nanoparticles have a significant impact both on the water diffusion behavior and the interfacial potential barrier across the interface between BN and MO. In the MO system directly doped by BN nanospheres, water diffusion behavior is not significantly restricted. However, grafting -NH2 polar groups onto the BN nanoparticle surface may significantly limit the diffusion behavior of water due to the strong attraction between the -NH2 polar groups and water molecules; the most significant effect is with nanospheres, followed by nanotubes and nanosheets. In terms of electrical properties across the interface between BN and MO, the h-BN surface (derived from BN nanosheets and nanotubes) acts as a trap for electrons in MO (-0.59 eV), while the c-BN surface (derived from BN nanospheres) acts as a potential barrier for electrons in MO (1.45 eV), and it is noteworthy that the presence of water molecules near the interface between BN and MO has little impact on the potential barriers. Advancing a fundamental understanding of the electrical and water diffusion properties of MO in correlation with the surface morphology of different types of nanoparticles is key to improving the insulation properties of oil-impregnated power transformers.

3.
Angew Chem Int Ed Engl ; : e202413069, 2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-39045802

RESUMO

Lanthanide-based upconversion molecular complexes have potential application in diverse fields and attracted considerable research interest in recent years. However, the similar coordination reactivity of lanthanide ions has constrained the designability of target molecule with well-defined structure, and many attempts obtained statistical mixtures. Herein, an ion-paired Yb-Eu heteronuclear complex [Eu(TpPy)2][Yb(ND)4] (TpPy = tris[3-(2-pyridyl)pyrazolyl]hydroborate, ND = 3-cyano-2-methyl-1,5-naphthyridin-4-olate) was designed and synthesized. Thanks to the radius difference between Eu3+ (1.07 Å) and Yb3+ (0.98 Å) ions, the hexadentate TpPy ligand was selected to coordinate with Eu3+ and the Yb3+ with a smaller radius was chelated by bidentate ND ligand. As a result, the sites of Eu3+ and Yb3+ in the complex can be clarified by high-resolution mass spectrometry and single-crystal structure analysis. Upon the excitation of Yb3+ at 980 nm, the upconversion emission of Eu3+ was realized through a cooperative sensitization process. Furthermore, [Eu(TpPy)2][Yb(ND)4] demonstrated excellent photostability during continuous high-power density 980 nm laser irradiation, with a LT95 (the time to 95% of the initial emission intensity) of 420 minutes. This work provides the first example of a pure ion-paired Yb-Eu heteronuclear complex upconversion system and may bring insights into rational design of lanthanide-based upconversion molecular complexes.

4.
Phys Rev Lett ; 132(16): 165002, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38701476

RESUMO

We report the experimental measurement of millijoule terahertz (THz) radiation emitted in the backward direction from laser wakefields driven by a femtosecond laser pulse of few joules interacting with a gas target. By utilizing frequency-resolved energy measurement, it is found that the THz spectrum exhibits two peaks located at about 4.5 and 9.0 THz, respectively. In particular, the high frequency component emerges when the drive laser energy exceeds 1.26 J, at which electron acceleration in the forward direction is detected simultaneously. Theoretical analysis and particle-in-cell simulations indicate that the THz radiation is generated via mode conversion from the laser wakefields excited in plasma with an up-ramp profile, where radiations both at the local electron plasma frequency and its harmonics are produced. Such intense THz sources may find many applications in ultrafast science, e.g., manipulating the transient states of matter.

5.
Opt Lett ; 48(23): 6312-6315, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38039255

RESUMO

We demonstrate the first, to the best of our knowledge, experimental observation of higher-order topological corner states in the photonic two-dimensional (2D) trimer lattices. Using a femtosecond laser direct writing technology, we experimentally fabricate a series of 2D trimer lattices with different open boundary conditions and thereby observe two kinds of 0D topological corner states, i.e., topological corner states and topological defect corner states. Interestingly, these corner states and defect corner states can not only exist in the bandgap but also coexist with the bulk states and show obvious localization properties. This work provides fresh perspectives on higher-order topology in artificial microstructures.

6.
Front Immunol ; 14: 1277955, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38111572

RESUMO

Background: Rhoptry organelle proteins (ROPs) secreted by apicomplexan parasites play important roles during parasites invasion and survival in host cells, and are potential vaccine candidates against apicomplexan diseases. Eimeria tenella (E. tenella) is one of the most noteworthy apicomplexan species, which causes hemorrhagic pathologies. Although dozens of putative E. tenella ROP sequences are annotated, most ROP proteins are not well studied. Methods: In this study, an E. tenella ROP21 gene was identified and the recombinant EtROP21 protein (rEtROP21) was expressed in Escherichia coli. The developmental expression levels, localization, and protective efficacy against E. tenella infection in chickens were studied. Results: An EtROP21 gene fragment with an open reading frame (ORF) of 981 bp was obtained from the Beijing strain of E. tenella. The rEtROP21 has a molecular weight of approximately 50 kDa and was recognized by rEtROP21-immunized mouse serum. Two specific protein bands, about 43 KDa and 95 KDa in size, were detected in the whole sporozoite proteins using the rEtROP21-immunized chicken serum. RT-qPCR analysis of the E. tenella ROP21 gene (EtROP21) revealed that its mRNA levels were higher in merozoites and sporozoites than in sporulated and unsporulated oocysts. Immunofluorescence and immunoelectron analyses showed that the EtROP21 protein predominantly localizes in the bulb region of rhoptries distributed at anterior, posterior, and perinuclear regions of E. tenella sporozoites. Immunization and challenge experiments revealed that immunizing chickens with rEtROP21 significantly increased their average body weight gain while decreasing mean lesion score and oocyst output (P <0.05). When compared with the challenged control group, the rEtROP21-immunized group was associated with a significantly higher relative weight gain (90.2%) and a greater reduction in oocyst output (67%) (P <0.05). The anticoccidial index of the rEtROP21-immunized group was 163.2. Chicken serum ELISA revealed that the levels of the specific anti- rEtROP21 antibody, IFN-γ, and IL-4 were significantly higher in the rEtROP21-immunized group than in the challenged control group (P <0.05). Conclusion: These results indicate that rEtROP21 can induce a high level of specific immune response and it is a potential candidate for the development of vaccines against E. tenella infection in chickens.


Assuntos
Coccidiose , Eimeria tenella , Animais , Camundongos , Proteínas de Protozoários , Coccidiose/prevenção & controle , Coccidiose/veterinária , Galinhas , Proteínas Recombinantes , Esporozoítos , Oocistos/metabolismo
7.
Vet Parasitol ; 324: 110072, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37944350

RESUMO

Toxoplasma gondii and Neospora caninum are two major apicomplexan protozoan parasites with heteroxenous life cycles and worldwide distributions. The transplacental transmission of N. caninum causes bovine abortion, which resulting in serious economic losses to the dairy industry. Although T. gondii was also reported to cause abortions in pregnant woman and small ruminants, scarce cases about the symptom to the host cattle and the causality remains unknown. In this study, transcriptome analysis of Madin Darby bovine kidney (MDBK) cells infected with T. gondii and N. caninum was performed to uncover the differences in susceptibility of cattle to the two parasites. The results showed that 256 and 2225 differentially expressed genes (DEGs) were detected in cells infected with N. caninum and T. gondii, respectively. Moreover, significant biological differences were revealed by the functional analysis including GO and KEGG enrichment. One serpin peptidase inhibitor (SEPRINA14), which is associated with immunosuppression during pregnancy, was found to significantly decrease in cells infected with N. caninum and increase in cells infected with T. gondii-infected cells. Pattern recognition receptors TLR3 and NOD2 were also significantly upregulated in N. caninum-infected MDBK cells, but not in T. gondii. They could induce an increased inflammatory response leading to severe tissue damage. In addition, the interleukin 12 receptor subunit beta 2 (IL12ß2), which plays an essential role in Th1 and Th2 cell differentiation and inflammatory bowel disease, was also markedly upregulated in the N. caninum infected cells, which led to an imbalance in the Th1 and Th2 cells by promoting the Th1 cellular response. Altogether, our findings recognized a new understanding on the differences between T. gondii and N. caninum infection of MDBK cells, where SEPRINA14, TLR3, NOD2, and IL12ß2 may be the key genes that affect the difference in susceptibility of cattle to T. gondii and N. caninum, especially in pregnant animals. This study provides more clues as to why N. caninum is more likely to cause abortions in cattle.


Assuntos
Doenças dos Bovinos , Coccidiose , Neospora , Toxoplasma , Toxoplasmose Animal , Humanos , Gravidez , Feminino , Bovinos , Animais , Toxoplasma/genética , Coccidiose/genética , Coccidiose/veterinária , Coccidiose/parasitologia , Receptor 3 Toll-Like/genética , Anticorpos Antiprotozoários , Doenças dos Bovinos/genética , Doenças dos Bovinos/parasitologia , Perfilação da Expressão Gênica/veterinária , Estudos Soroepidemiológicos
8.
Molecules ; 28(20)2023 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-37894613

RESUMO

Cation-anion co-doping has proven to be an effective method of improving the photocatalytic performances of CaTiO3 perovskites. In this regard, (La/Ce-N/S) co-doped CaTiO3 models were investigated for the first time using first-principles calculations based on a supercell of 2 × 2 × 2 with La/Ce concentrations of 0.125, 0.25, and 0.375. The energy band structure, density of states, charge differential density, electron-hole effective masses, optical properties, and the water redox potential were calculated for various models. According to our results, (La-S)-doped CaTiO3 with a doping ratio of 0.25 (LCOS1-0.25) has superior photocatalytic hydrolysis properties due to the synergistic performances of its narrow band gap, fast carrier mobility, and superb ability to absorb visible light. Apart from the reduction of the band gap, the introduction of intermediate energy levels by La and Ce within the band gap also facilitates the transition of excited electrons from valence to the conduction band. Our calculations and findings provide theoretical insights and solid predictions for discovering CaTiO3 perovskites with excellent photocatalysis performances.

9.
Opt Lett ; 48(17): 4532-4535, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37656546

RESUMO

Bound states in the continuum (BICs) are intriguing localized states that possess eigenvalues embedded within the continuum of extended states. Recently, a combination of topological band theory and BIC physics has given rise to a novel form of topological matter known as topological BICs. In this work, we experimentally demonstrate the photonic topological subspace-induced BICs. By using femtosecond-laser writing, we experimentally establish a photonic nontrivial three-leg ladder lattice, thereby directly observe the localized propagation of two kinds of topological edge states which exist at different boundaries. Interestingly, such edge states appear in the continuum of the bulk modes, and the topological properties are inherited from its independent subspace Hamiltonian which contains a celebrated Su-Schrieffer-Heeger lattice. This work not only presents a novel, to the best of our knowledge, platform for investigating topological physics in optics, but also unveils exciting prospects for future exploration of other remarkable BICs.

10.
Front Cell Infect Microbiol ; 13: 1205782, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37469602

RESUMO

Introduction: Vacuolar protein sorting 29 (VPS29) is a core component of the retromer-retriever complex and is essential for recycling numerous cell-surface cargoes from endosomes. However, there are no reports yet on VPS29 of Eimeria spp. Methods: Here, we cloned and prokaryotically expressed a partial sequence of Eimeria tenella VPS29 (EtVPS29) with RT-PCR and engineered strain of Escherichia coli respectively. The localization of the VPS29 protein in E. tenella sporozoites was investigated with immunofluorescence (IFA) and overexpression assays. And its protective efficacy against E. tenella infection was investigated in chickens with the animal protection test. Results: An EtVPS29 gene fragment with an ORF reading frame of 549 bp was cloned. The band size of the expressed recombinant protein, rEtVPS29, was approximately 39 kDa and was recognized by the chicken anti-E. tenella positive serum. EtVPS29 protein was observed widely distributing in the cytoplasm of E. tenella sporozoites in the IFA and overexpression assays. rEtVPS29 significantly increased average body weight gain and decreased mean lesion score and oocyst output in chickens. The relative weight gain rate in the rEtVPS29-immunized group was 62.9%, which was significantly higher than that in the unimmunized and challenged group (P < 0.05). The percentage of reduced oocyst output in the rEtVPS29 immunized group was 32.2%. The anticoccidial index of the rEtVPS29-immunized group was 144.2. Serum ELISA also showed that rEtVPS29 immunization induced high levels of specific antibodies in chickens. Discussion: These results suggest that rEtVPS29 can induce a specific immune response and is a potential candidate for the development of novel vaccines against E. tenella infections in chickens.


Assuntos
Eimeria tenella , Doenças das Aves Domésticas , Vacinas Protozoárias , Animais , Eimeria tenella/genética , Galinhas , Proteínas Recombinantes/metabolismo , Imunização , Vacinação/veterinária , Oocistos/metabolismo , Esporozoítos , Doenças das Aves Domésticas/prevenção & controle , Vacinas Protozoárias/genética
11.
Int J Mol Sci ; 24(13)2023 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-37445967

RESUMO

Balantioides coli plays an important role in the diarrhea of weaned piglets, but its pathogenic potential and interaction with gut microbes remain unclear. To investigate the impact of B. coli colonization on the gut bacterial structure and function of weaned piglets, a metagenomic analysis based on shotgun sequencing was performed on fresh fecal samples collected from ten B. coli-colonized piglets and eight B. coli-free ones in this study. The results showed that decreasing diversity and shifted composition and function of the bacterial community were detected in the weaned piglets infected by B. coli. In contrast to the B. coli-negative group, the relative abundances of some members of the Firmicutes phylum including Clostridium, Ruminococcus species, and Intestinimonas butyriciproducens, which produce short-chain fatty acids, were significantly reduced in the B. coli-positive group. Notably, some species of the Prevotella genus (such as Prevotella sp. CAG:604 and Prevotella stercorea) were significantly increased in abundance in the B. coli-positive piglets. A functional analysis of the gut microbiota demonstrated that the differential gene sets for the metabolism of carbohydrates and amino acids were abundant in both groups, and the more enriched pathways in B. coli-infected piglets were associated with the sugar-specific phosphotransferase system (PTS) and the two-component regulatory system, as well as lipopolysaccharide (LPS) biosynthesis. Furthermore, several species of Prevotella were significantly positively correlated to the synthesis of lipid A, leading to the exporting of endotoxins and, thereby, inducing inflammation in the intestines of weaned piglets. Taken together, these findings revealed that colonization by B. coli was distinctly associated with the dysbiosis of gut bacterial structure and function in weaned piglets. Lower relative abundances of Clostridiaceae and Ruminococcaceae and higher abundances of Prevotella species were biomarkers of B. coli infection in weaned piglets.


Assuntos
Balantidíase , Microbioma Gastrointestinal , Suínos , Animais , Microbioma Gastrointestinal/genética , Metagenoma , Virulência , Diarreia/microbiologia
12.
Opt Lett ; 48(14): 3765-3768, 2023 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-37450745

RESUMO

Recently, there has been a surge of interest in square-root higher-order topological insulators (HOTIs) due to their unique topological properties inherited from their squared Hamiltonian. Different from conventional HOTIs, square-root HOTIs support paired corner states that exist in different bandgaps. In this work, we experimentally establish a series of two-dimensional photonic decorated Su-Schrieffer-Heeger (SSH) lattices by using the femtosecond-laser writing technique and thereby directly observe paired topological corner states. Interestingly, the higher-order topological properties of such square-root HOTIs are inherited from the parent Hamiltonian, which contains the celebrated 2D SSH lattice. The dynamic evolution of square-root corner states indicates that they exist in different bandgaps. This work not only provides a new platform to study higher-order topology in optics, it also brings about new possibilities for future studies of other novel HOTIs.


Assuntos
Fótons , Redação
13.
Phys Rev Lett ; 130(21): 215001, 2023 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-37295115

RESUMO

Curved plasma channels have been proposed to guide intense lasers for various applications, such as x-ray laser emission, compact synchrotron radiation, and multistage laser wakefield acceleration [e.g. J. Luo et al., Phys. Rev. Lett. 120, 154801 (2018)PRLTAO0031-900710.1103/PhysRevLett.120.154801]. Here, a carefully designed experiment shows evidences of intense laser guidance and wakefield acceleration in a centimeter-scale curved plasma channel. Both experiments and simulations indicate that when the channel curvature radius is gradually increased and the laser incidence offset is optimized, the transverse oscillation of the laser beam can be mitigated, and the stably guided laser pulse excites wakefields and accelerates electrons along the curved plasma channel to a maximum energy of 0.7 GeV. Our results also show that such a channel exhibits good potential for seamless multistage laser wakefield acceleration.


Assuntos
Aceleração , Elétrons , Frequência Cardíaca , Lasers , Plasma
14.
Animals (Basel) ; 13(10)2023 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-37238038

RESUMO

Carbohydrates are the main source of nutrition for B. coli, supplying energy for cell growth and development. The research aimed at investigating the mechanism of starch on the growth and replication of B. coli. Single-cell separation was used to isolate single trophozoites of B. coli under a stereomicroscope, transcriptomic profiling was conducted based on the SMART-seq2 single-cell RNA-seq method. Comparative genomic analysis was performed on B. coli and eight other ciliates to obtain specific and expanded gene families of B. coli. GO and KEGG enrichment analysis were used to analyze the key genes of B. coli under the action of starch in the present study. The results of single-cell RNA-seq depicts starch affected the growth and replication of B. coli in two ways: (1) the cell cycle was positively promoted by the activation of the cAMP/PKA signaling pathway via glycolysis; (2) the cell autophagy was suppressed through the PI3K/AKT/mTOR pathway. Genes involved in endocytosis, carbohydrate utilization, and the cAMP/PKA signaling pathway were highly enriched in both specific and expanded gene families of B. coli. Starch can be ingested and hydrolyzed into glucose, in turn affecting various biological processes of B. coli. The molecular mechanism of the effect of starch on the growth and proliferation of B. coli by promoting cell cycle and inhibiting the autophagy of trophozoites has been elucidated in our study.

15.
Opt Lett ; 48(7): 1802-1805, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-37221770

RESUMO

In recent years, topological insulators have been extensively studied in one-dimensional periodic systems, such as Su-Schrieffer-Heeger and trimer lattices. The remarkable feature of these one-dimensional models is that they support topological edge states, which are protected by lattice symmetry. To further study the role of lattice symmetry in one-dimensional topological insulators, here we design a modified version of the conventional trimer lattices, i.e., decorated trimer lattices. Using the femtosecond laser writing technique, we experimentally establish a series of one-dimensional photonic decorated trimer lattices with and without inversion symmetry, thereby directly observing three kinds of topological edge state. Interestingly, we demonstrate that the additional vertical intracell coupling strength in our model can change the energy band spectrum, thereby generating unconventional topological edge states with a longer localization length in another boundary. This work offers novel insight into topological insulators in one-dimensional photonic lattices.

16.
Inorg Chem ; 62(17): 6560-6564, 2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-37083359

RESUMO

Herein, a deuteration strategy is proposed to enhance the photoluminescence quantum yield (PLQY) of a Dy(III) complex. The perdeuterated Dy(III) complex Dy(D-DPPOP)3 (D-DPPOP = 6-[bis(phenyl-d5)phosphoryl]picolinate-d3) exhibits a high PLQY of up to 72% in deuterated chloroform, which is 4.8 times higher than that of the nondeuterated Dy(III) complex Dy(DPPOP)3. Then the corresponding ultraviolet-excited light-emitting diode is fabricated, showing a warm-white light with a Commission Internationale de l'Eclairage (CIE) of (0.36, 0.41) and a color temperature of around 4800 K. The deuteration strategy to improve the PLQY of the Dy(III) complex is proved in this work, and it will inspire the further design of white-emission Dy(III) complexes with high efficiency.

17.
Mater Horiz ; 10(2): 625-631, 2023 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-36515011

RESUMO

A new heteronuclear EuII-MnII complex [Eu(N2O6)]MnBr4 (N2O6 = 4,7,13,16,21,24-hexaoxa-1,10-diazabicyclo[8.8.8]hexacosane) is designed and synthesized, which shows an intense green emission from MnII with a near-unity photoluminescence quantum yield. Measurement of excited-state dynamics demonstrated the sensitization process from EuII to MnII, which represents the first example of f → d molecular sensitization. Due to the large optical absorption cross-section of the EuII center, [Eu(N2O6)]MnBr4 shows an emission intensity 7 to 2500 times stronger than that of the SrII-MnII control complex [Sr(N2O6)]MnBr4 upon the excitation of near ultraviolet to blue light.

18.
Anal Chem ; 94(43): 14820-14826, 2022 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-36260072

RESUMO

We report a living cell-target responsive accessibility profiling (LC-TRAP) approach to identify the targetome of silibinin (SIL), a well-established hepatoprotective natural product (NP), in HepG2 cells. Proteins showing accessibility changes, probed by covalent lysine labeling reagents and leveraged by multiplexed quantitative proteomics, following the administration of SIL to the living cells were assigned as potential targets. Among the assigned targetome, ACSL4, an enzyme essential for ferroptosis induction, might be involved in the hepatoprotective effects of SIL and hence was intensively validated. We first demonstrated that SIL protected HepG2 cells from ferroptosis dependent on ACSL4. Then, we used biophysical assays and a SIL-derivatized chemical probe to corroborate that SIL can bind to ACSL4. The ensuing enzymatic assays showed that SIL inhibited ACSL4 enzymatic activity, thereby mitigating the ACSL4-mediated ferroptosis. As such, we revealed that ACSL4 inhibition, using SIL as a model compound, represents a promising hepatoprotective strategy. Further, since TRAP probes the accessibility changes of reactive proteinaceous lysines, it can pinpoint the proximal regions where the ligand engagement may occur. Thus, the LC-TRAP analysis of SIL, the newly discovered ligand of ACSL4, and arachidonic acid (AA), the substrate, intriguingly showed that SIL and AA both affected the conformation of the K536-proximal region of ACSL4, albeit through distinct binding patterns. Collectively, we describe a straightforward LC-TRAP workflow that does not involve ligand-derived probe synthesis and is widely applicable to target discovery of NPs.


Assuntos
Ferroptose , Humanos , Silibina/farmacologia , Coenzima A Ligases/metabolismo , Ligantes , Células Hep G2 , Ácido Araquidônico
19.
Parasit Vectors ; 15(1): 332, 2022 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-36138417

RESUMO

BACKGROUND: Melanoma is a malignant tumor with a high mortality rate. Some microorganisms have been shown to activate the immune system and limit cancer progression. The objective of this study is to evaluate the anti-melanoma effect of Neospora caninum, a livestock pathogen with no pathogenic activity in humans. METHODS: Neospora caninum tachyzoites were inoculated into a C57BL/6 mouse melanoma model by intratumoral and distal subcutaneous injections. Tumor volumes were measured, and cell death areas were visualized by hematoxylin and eosin staining and quantified. Apoptosis in cell cultures and whole tumors was detected by propidium iodide (PI) and TUNEL staining, respectively. Cytokine and tumor-associated factor levels in tumors and spleens were detected by real-time quantitative polymerase chain reaction. Infiltration of macrophages and CD8+ T cells in the tumor microenvironment (TME) were detected by immunohistochemistry with anti-CD68 and anti-CD8 antibodies, respectively. Finally, 16S rRNA sequencing of mice cecal contents was performed to evaluate the effect of N. caninum on gut microbial diversity. RESULTS: Intratumoral and distal subcutaneous injections of N. caninum resulted in significant inhibition of tumor growth (P < 0.001), and more than 50% of tumor cells were dead without signs of apoptosis. Neospora caninum treatment significantly increased the mRNA expression levels of IL-12, IFN-γ, IL-2, IL-10, TNF-α, and PD-L1 in the TME, and IL-12 and IFN-γ in the spleen of tumor-bearing mice (P < 0.05). An increase in the infiltration of CD8+ T cells and macrophages in the TME was observed with these cytokine changes. Neospora caninum also restored the abundance of gut microbiota Lactobacillus, Lachnospiraceae, Adlercreutzia, and Prevotellaceae associated with tumor growth, but the changes were not significant. CONCLUSION: Neospora caninum inhibits B16F10 melanoma by activating potent immune responses and directly destroying the cancer cells. The stable, non-toxic, and efficacious properties of N. caninum demonstrate the potential for its use as a cancer treatment.


Assuntos
Neoplasias , Neospora , Animais , Antígeno B7-H1 , Linfócitos T CD8-Positivos , Citocinas/metabolismo , Amarelo de Eosina-(YS) , Hematoxilina , Imunidade , Interleucina-10 , Interleucina-12 , Interleucina-2 , Camundongos , Camundongos Endogâmicos C57BL , Neoplasias/imunologia , Neoplasias/prevenção & controle , Propídio , RNA Mensageiro , RNA Ribossômico 16S , Fator de Necrose Tumoral alfa
20.
Environ Technol ; : 1-10, 2022 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-36036221

RESUMO

⋅OHThe wet denitrification technology has a good development prospect due to its simple system and mild reaction conditions, and related research has become a hot topic in the field of flue gas purification. In this work, a novel simultaneous removal technology of NO from flue gas using Fe2+/Cu2+-catalytic H2O2/(NH4)2S2O8 system was developed for the first time. The feasibility of this new flue gas cleaning technology was explored through a series of experiments and performance analyses. The mechanism of oxidation products, free radicals and simultaneous removal of NO was revealed. The effects of the main process parameters on the removal of NO were investigated. Relevant results demonstrated that the removal efficiency of NO was elevated when the concentration of (NH4)2S2O8 or reacting temperature increased, while it was decreased after increasing the raising of Fe2+, Cu2+ and H2O2 concentrations. The main radicals were and·SO4-, using the electron spin resonance technique in the solution, and played a very important role in NO removal. The main products were carried out by ion chromatography and elemental N material accountancy, and the results showed that it was sulfate and nitrate in the solution, which provided theoretical guidance for the subsequent treatment and resource utilization of the absorption solution. The results of the study provided a theoretical basis for the industrial application of wet denitrification.

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