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1.
J Oncol ; 2022: 8035083, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36052282

RESUMO

Background: Circular RNAs (circRNAs) regulate complex functional processes and play crucial roles in cancer development and progression. It was reported that circKIF4 regulates the progression of triple-negative breast cancer (TNBC). This study evaluates the role of circKIF4 in breast cancer distant metastasis and metabolic reprogramming. Methods: RT-qPCR was performed to verify the expression of circKIF4A in breast cancer, liver metastatic tissues, and cell lines. The function of circKIF4A in metastasis was evaluated both in vitro and in vivo through a series of experiments, including cell migration and glucose intake experiments. Additionally, we conducted molecular experiments to clarify the regulatory role of circKIF4A. We then conducted a Luciferase reporter assay and an RNA immunoprecipitation assay to identify the molecular interactions between circKIF4A and miRNA. Results: circKIF4A was overexpressed in breast cancer cell lines and tissues, inhibiting its expression and suppressing breast cancer growth and metastasis. Interestingly, we observed that circKIF4A reprogrammed the glucose metabolism of breast cancer, and silencing circKIF4A greatly affected glucose uptake and lactate production in breast cancer cells. miR-335 can be sponged by circKIF4A, which affected the expression of ALDOA/OCT4 protein and regulated HK2/PKM2 expression. Conclusions: This study demonstrated that the circKIF4A-miR-335-OCT4/ALDOA-HK2/PKM2 axis is critical to breast cancer metabolic reprogramming, indicating that this axis could be a novel therapeutic target for the treatment of liver metastasis of breast cancer.

2.
Front Cardiovasc Med ; 9: 952430, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36072857

RESUMO

Background: Sex hormones are associated with many cardiovascular risk factors, but their effects on atrial fibrillation (AF) incidence remain unclear. This systematic review and meta-analysis aimed to evaluate the association of circulating sex hormones with AF risk by pooling available data from observational studies. Methods: A systematic literature search for pertinent articles with case-control and cohort designs was conducted via five databases up to 7 July 2021. A meta-analysis with six cohort studies was conducted separately on men and women. Adjusted relative risk (RR) with a 95% confidence interval (CI) was derived by comparing the highest with the lowest levels of a specific sex hormone and by using a random-effect or fixed-effect model. Heterogeneity was tested using the I 2 statistic and the Q-test. Results: A total of six cohort studies and four case-control studies were included. In a meta-analysis of cohort studies, dehydroepiandrosterone sulfate (DHEAS) was associated with a decreased risk of AF in men (RR: 0.729, 95% CI: 0.559-0.952, I 2 = 50.0%, P -heterogeneity = 0.157) after combining results from two cohort studies; total testosterone was not associated with any risk of AF in men and postmenopausal women, and AF risk was not associated with estradiol in men after synthesizing available studies. Conclusion: This study indicates that a higher endogenous DHEAS level was associated with a lower AF risk in men, whereas total testosterone and estradiol were not associated with AF risk. Longitudinal studies with multiple monitoring are needed to further promulgate the relationship between various circulating sex hormones and AF risk.

3.
Huan Jing Ke Xue ; 43(9): 4497-4505, 2022 Sep 08.
Artigo em Chinês | MEDLINE | ID: mdl-36096590

RESUMO

To investigate the characteristics and sources of atmospheric volatile organic compounds (VOCs) in a typical industrial zone in Dongguan, 56 VOCs species were continuously measured in Houjie Town of Dongguan in summer of 2020. In addition, mass concentrations of O3, NOx, and CO and meteorological data were synchronously collected. Then, characteristics of total VOCs and major species, the contributions of major VOCs species to ozone formation potential (OFP), and source apportionment of VOCs under the different ozone concentrations were discussed. The mean mixing ratio of VOCs was 53.1×10-9 including aromatics (24.7×10-9), alkanes (23.7×10-9), alkenes (3.9×10-9), and alkynes (0.7×10-9). The mean mixing ratios of aromatics, alkanes, alkenes, and alkynes increased approximately 10%, 43%, 38%, and 98% during the period of ozone pollution, respectively, compared with those during the period of non-ozone pollution. Aromatics contributed the most to OFP during the periods of both ozone pollution and non-ozone pollution, followed by alkanes, alkenes, and alkynes. Solvent sources, liquefied petroleum gas (LPG) leakage, fossil fuel combustion, and hydrocarbon volatilization were resolved using the PMF model, which accounted for 60%±20%, 16%±11%, 15%±11%, and 9%±6% of total VOCs, respectively. During the period of ozone pollution, the contribution of solvent sources to the total VOCs decreased to 44%, whereas that of LPG leakage and hydrocarbon volatilization increased to 21% and 16%, respectively.


Assuntos
Poluentes Atmosféricos , Ozônio , Compostos Orgânicos Voláteis , Poluentes Atmosféricos/análise , Alcanos/análise , Alcenos/análise , Alcinos , Monitoramento Ambiental , Hidrocarbonetos , Ozônio/análise , Solventes , Compostos Orgânicos Voláteis/análise
4.
Materials (Basel) ; 15(17)2022 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-36079516

RESUMO

The finite element method (FEM) is used to investigate the free and forced vibration characteristics of functionally graded graphene-nanoplatelet-reinforced composite (FG-GPLRC) beams. The weight fraction of graphene nanoplatelets (GPLs) is assumed to vary continuously along the beam thickness according to a linear, parabolic, or uniform pattern. For the FG-GPLRC beam, the modified Halpin-Tsai micromechanics model is used to calculate the effective Young's modulus, and the rule of mixture is used to determine the effective Poisson's ratio and mass density. Based on the principle of virtual work under the assumptions of the Euler-Bernoulli beam theory, finite element formulations are derived to analyze the free and forced vibration characteristics of FG-GPLRC beams. A two-node beam element with six degrees of freedom is adopted to discretize the beam, and the corresponding stiffness matrix and mass matrix containing information on the variation of material properties can be derived. On this basis, the natural frequencies and the response amplitudes under external forces are calculated by the FEM. The performance of the proposed FEM is assessed, with some numerical results obtained by layering method and available in published literature. The comparison results show that the proposed FEM is capable of analyzing an FG-GPLRC beam. A detailed parametric investigation is carried out to study the effects of GPL weight fraction, distribution pattern, and dimensions on the free and forced vibration responses of the beam. Numerical results show that the above-mentioned effects play an important role with respect to the vibration behaviors of the beam.

5.
Molecules ; 27(18)2022 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-36144828

RESUMO

Salvianic acid A (SAA), as the main bioactive component of the traditional Chinese herb Salvia miltiorrhiza, has important application value in the treatment of cardiovascular diseases. In this study, a two-step bioprocess for the preparation of SAA from l-DOPA was developed. In the first step, l-DOPA was transformed to 3,4-dihydroxyphenylalanine (DHPPA) using engineered Escherichia coli cells expressing membrane-bound L-amino acid deaminase from Proteus vulgaris. After that, the unpurified DHPPA was directly converted into SAA by permeabilized recombinant E. coli cells co-expressing d-lactate dehydrogenase from Pediococcus acidilactici and formate dehydrogenase from Mycobacterium vaccae N10. Under optimized conditions, 48.3 mM of SAA could be prepared from 50 mM of l-DOPA, with a yield of 96.6%. Therefore, the bioprocess developed here was not only environmentally friendly, but also exhibited excellent production efficiency and, thus, is promising for industrial SAA production.


Assuntos
Escherichia coli , Levodopa , Biocatálise , Escherichia coli/genética , Formiato Desidrogenases , Ácidos Fenilpirúvicos
6.
Reprod Biol Endocrinol ; 20(1): 138, 2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-36109751

RESUMO

BACKGROUND: Circular RNAs (circRNAs) play a vital role in cancer progression. However, there are still numerous circRNAs that have not been functionally explored. Our study aimed to disclose the role of circ-CSNK1G1 in triple-negative breast cancer (TNBC). METHODS: The expression of circ-CSNK1G1, miR-28-5p and lactate dehydrogenase A (LDHA) mRNA was measured by quantitative real-time polymerase chain reaction (qPCR), and the expression of LDHA protein was measured by western blot. Cell proliferation was assessed using MTT assay and colony formation assay. Cell apoptosis was monitored using flow cytometry assay. Cell migration and cell invasion were investigated using transwell assay. Glycolysis progression was assessed according to glucose consumption, lactate production and ATP/ADP ratio. Tumor formation assay in nude mice was conducted to verify the role of circ-CSNK1G1 in vivo. The interplays between miR-28-5p and circ-CSNK1G1 or LDHA were confirmed by dual-luciferase reporter assay. RESULTS: Circ-CSNK1G1 was upregulated in TNBC tissues and cells. Circ-CSNK1G1 knockdown suppressed cancer cell proliferation, migration, invasion and glycolysis energy metabolism, promoted cell apoptosis in vitro, and blocked tumor growth in vivo. Mechanism analysis showed that circ-CSNK1G1 positively regulated LDHA expression by suppressing miR-28-5p. Rescue experiments presented that circ-CSNK1G1 played functions by targeting miR-28-5p, and miR-28-5p participated in TNBC progression by degrading LDHA. CONCLUSION: Circ-CSNK1G1 promotes cell proliferation, migration, invasion and glycolysis metabolism during TNBC development by regulating the miR-28-5p/LDHA pathway.


Assuntos
L-Lactato Desidrogenase , MicroRNAs , Neoplasias de Mama Triplo Negativas , Difosfato de Adenosina/metabolismo , Trifosfato de Adenosina/metabolismo , Animais , Linhagem Celular Tumoral , Proliferação de Células/genética , Glucose , Glicólise/genética , Humanos , L-Lactato Desidrogenase/genética , Camundongos , Camundongos Nus , MicroRNAs/genética , MicroRNAs/metabolismo , RNA Circular/genética , RNA Mensageiro/metabolismo , Neoplasias de Mama Triplo Negativas/genética
7.
Comput Intell Neurosci ; 2022: 7368771, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36156941

RESUMO

With the development of information technology, teaching reform has also undergone major changes. The traditional college physical education teaching method cannot meet the needs of the majority of students, and the physical education teaching mode continues to be reformed. Microcourse is the most intuitive form of deep integration of information technology and physical education. From the perspective of the flipped classroom (FC), the physical education model has gradually changed from teacher centered to student centered. Deep learning (DL) emphasizes that learners have the ability to actively construct knowledge, effectively transfer knowledge, and solve real problems. This design applies DL and convolutional neural network to the teaching design of physical gymnastics in colleges and universities. The application of the DL teaching model based on FC in the microcourse teaching of gymnastics in colleges and universities is studied and evaluated. The results show that the current utilization of microcourse teaching resources is too low. Interest-oriented teaching microcourses cannot improve students' interests. The proportion of students who are interested is relatively small, and more than 50% of students are not interested. Teachers generally believe that the current gymnastics microcourse needs further optimization and improvement. The poor quality of microvideos and the lack of supervision and reward mechanism in the course are the main reasons for the insufficient students' interest. The complexity of the videos and the liveliness of the discussions are the main problems of low resource utilization. The student's interest in learning is greatly improved after the application of the designed model, and the proportion increases to 82.4%. The effect on ordinary college students is the most obvious, and the effect of microvideo learning has been significantly promoted. Design mode has the most obvious improvement in improving learning efficiency and autonomous learning ability. The improvement of learning ability has increased from 18% to 72%, and the improvement of learning efficiency has increased from 39% to 82%. Meanwhile, students' interest in learning is stimulated, and the utilization of resources is improved.


Assuntos
Aprendizado Profundo , Educação Física e Treinamento , Humanos , Estudantes , Universidades
8.
Chem Biol Interact ; 366: 110148, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-36084724

RESUMO

Ferroptosis is a novel form of regulated cell death that has a close association with mitochondrial dysfunction and is characterized by iron overload, the accumulation of reactive oxygen species (ROS), and lipid ROS. Chondrocytes ferroptosis accelerates the progression of osteoarthritis (OA). Astaxanthin (ATX) is a xanthophyll carotenoid that possesses anti-inflammatory and antioxidant properties and has been explored in research studies for the treatment of diabetes and cardiovascular disease. However, the role it plays in OA, particularly in chondrocyte ferroptosis, has not yet been reported. In this study, ferroptosis-related events were analyzed in rat chondrocytes in vitro. A surgical destabilized medial meniscus was performed for the establishment of in vivo OA model. The results showed that interleukin-1ß (IL-1ß) induced inflammatory injury in chondrocytes through the promotion of the expressions of inflammatory factors including inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX2). IL-1ß triggered chondrocyte ferroptosis by increasing the levels of intracellular ROS, lipid ROS, iron, and mitochondrial iron and inhibiting the expressions of SLC7A11/glutathione peroxidase 4 (GPX4) and Ferritin. The above indices were ameliorated by ferrostatin-1 (Fer-1, a classic ferroptosis inhibitor) and ATX. Furthermore, Fer-1 and ATX rescued the IL-1ß-induced down-regulating collagen type II (collagen Ⅱ) and up-regulating matrix metalloproteinase 13 (MMP13). Following treatment with IL-1ß, mitochondrial membrane potential decreased and the mitochondrial membrane was broken. At the same time, the mitochondrion shrank, becoming deformed as the mitochondrial cristae reduced and became disrupted. These changes were entirely consistent with ferroptosis features. All the aforementioned phenomena were reversed by Fer-1 and ATX. In addition, intra-articular injection of Fer-1 and ATX delayed articular cartilage degradation and OA progression. This study demonstrated that IL-1ß can induce inflammatory damage and ferroptosis in chondrocytes. Both Fer-1 and ATX have the ability to mitigate chondrocyte injury and osteoarthritis progression by inhibiting ferroptosis and the regulation of mitochondrial function. Targeting ferroptosis has the potential to be a promising future treatment method for OA.


Assuntos
Ferroptose , Osteoartrite , Animais , Anti-Inflamatórios/farmacologia , Antioxidantes/metabolismo , Células Cultivadas , Condrócitos/metabolismo , Colágeno Tipo II/metabolismo , Ciclo-Oxigenase 2/metabolismo , Ferritinas/metabolismo , Interleucina-1beta/metabolismo , Ferro/metabolismo , Lipídeos , Metaloproteinase 13 da Matriz/metabolismo , Mitocôndrias/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Osteoartrite/tratamento farmacológico , Osteoartrite/metabolismo , Fosfolipídeo Hidroperóxido Glutationa Peroxidase , Ratos , Espécies Reativas de Oxigênio/metabolismo , Xantofilas/farmacologia , Xantofilas/uso terapêutico
9.
J Agric Food Chem ; 70(38): 11994-12003, 2022 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-36121904

RESUMO

Tenvermectins A and B (TVMs A and B) are hybrid natural compounds of avermectins and milbemycins with enhanced insecticidal activity. Aiming at obtaining a strain for the production of the higher activity metabolite-TVM-B as a major constituent, a recombinant strain Streptomyces avermitilis HU02 was constructed by a domain swapping strategy in which milA1-AT0 gene in S. avermitilis MHJ1011 was replaced by eryA1-AT0 gene from Saccharopolyspora erythraea ATCC 40137. Chemical investigation on the culture of S. avermitilis HU02 led to the isolation of a large amount of TVM-B and trace amounts of five new TVM-B analogues. The structures of new metabolites were elucidated by extensive spectroscopic analysis including 1D and 2D nuclear magnetic resonance and high-resolution electrospray ionization mass spectrometry data. The bioassay test indicated that five new TVM-B analogues exhibited potent insecticidal activity against Tetranychus cinnabarinus and Bursaphelenchus xylophilus. This study provided a feasible route to the low-cost production of TVM-B and enriched the structural diversity of TVM-B metabolites.


Assuntos
Acaricidas , Inseticidas , Acaricidas/química , Aciltransferases/metabolismo , Inseticidas/farmacologia , Ivermectina/farmacologia , Lactonas , Compostos Macrocíclicos , Estrutura Molecular , Streptomyces
10.
ISA Trans ; 2022 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-36175187

RESUMO

The issue of secure estimation for cyber-physical systems subject to unknown inputs and stealthy deception attacks is addressed in this paper. First, the unknown inputs are treated as augmented state and on the basis of that, the original plant is transformed into a singular system, which is decoupled with the unknown inputs. Then, for the purpose of reducing communication burden and avoiding congestion in the network, the event-triggered mechanism is introduced. Two approaches are presented to accomplish state estimation. The former one is known as the monotone system method. In the latter method, an input-to-state stable robust observer is constructed and by using the set-membership method, approximated estimation error is obtained. Finally, the effectiveness of the proposed method is verified by two illustrative examples.

11.
Foods ; 11(18)2022 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-36141055

RESUMO

Daqu provides functional microbiota and various nutrients for artificial pit mud (APM) cultivation. However, little is known about whether its attributes affect the microbiome and metabolome of APM. Here, two types of APM were manufactured by adding fortified Daqu (FD) and conventional Daqu (CD); they were comprehensively compared by polyphasic detection methods after being used for two years. The results showed that FD altered the prokaryotic communities rather than the fungal ones, resulting in increased archaea and Clostridium_sensu_stricto_12 and decreased eubacteria and Lactobacillus. Correlation analysis suggested that these variations in community structure promoted the formation of hexanoic acid, butyric acid, and the corresponding ethyl esters, whereas they inhibited that of lactic acid and ethyl lactate and thus improved the flavor quality of the APM. Notably, pH was the main driving factor for the bacterial community variation, and the total acid mediated the balance between the stochastic and the deterministic processes. Furthermore, the results of the network analysis and PICRUSt2 indicated that FD also enhanced the modularity and robustness of the co-occurrence network and the abundance of enzymes related to hexanoic acid and butyric acid production. Our study highlights the importance of Daqu attributes in APM cultivation, which are of great significance for the production of high-quality strong-flavor Baijiu.

12.
Int J Mol Sci ; 23(18)2022 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-36142144

RESUMO

Southern corn leaf blight is one of the most widespread foliar diseases in maize-producing areas worldwide and can seriously reduce the yield and quality of sweet corn. However, the molecular mechanisms underlying the disease in sweet corn have not been widely reported. In this study, two sweet corn inbred lines, resistant K13 (RK13) and susceptible K39 (SK39), were used to explore the disease resistance mechanism of southern leaf blight. We observed morphological characteristics and assessed the changes in protective enzymatic activity in sweet corn leaves after inoculation of C. heterostrophus. RNA-seq was performed to elucidate the transcriptional dynamics and reveal the key pathways involved in southern leaf blight resistance without pathogens (Mock) and at 1 and 3 days post inoculation (1 and 3 dpi). Differentially expressed genes (DEGs) were identified in the SK39 group (including three pairwise combinations: SK39-0d_vs_SK39-1d, SK39-1d_vs_SK39-3d and SK39-1d_vs_SK39-3d), the RK13 group (including three pairwise combinations: RK13-0d_vs_RK13-1d, RK13-1d_vs_RK13-3d and RK13-1d_vs_RK13-3d), and the SK39_vs_RK13 group (including three pairwise combinations: SK39-0d_vs_RK13-0d, SK39-1d_vs_RK13-1d, and SK39-3d_vs_RK13-3d). In our study, 9455 DEGs from the RK13 group, 9626 from the SK39 group, and 9051 DEGs from the SK39_vs_RK13 group were obtained. Furthermore, 2775, 163, and 185 DEGs were co-expressed at SK39_vs_RK13, RK13, and SK39, respectively. A functional analysis of the DEGs revealed that five pathways-i.e., photosynthesis, plant hormone signal transduction, MAPK signaling pathway, phenylpropanoid biosynthesis, and biosynthesis of secondary metabolites-and transcription factor families play crucial roles in disease resistance. The results from the present study enabled the identification of the JA and SA signaling pathways, which are potentially involved in the response to southern leaf blight in maize. Our findings also highlight the significance of ZIM transcription factors and pathogenesis-related (PR) genes during pathogen infection. This study preliminarily explored the molecular mechanisms of the interaction between sweet corn and C. heterostrophus and provides a reference for identifying southern leaf blight resistance genes in the future.


Assuntos
Resistência à Doença , Zea mays , Resistência à Doença/genética , Perfilação da Expressão Gênica/métodos , Regulação da Expressão Gênica de Plantas , Doenças das Plantas/genética , Reguladores de Crescimento de Plantas , Fatores de Transcrição/genética , Zea mays/genética
13.
Front Med (Lausanne) ; 9: 920760, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36111119

RESUMO

Background: Limited evidence was available on the association of the integrated effect of multidimensional lifestyle factors with mortality among Chinese populations. This cohort study was to examine the effect of combined lifestyle factors on the risk of mortality by highlighting the number of healthy lifestyles and their overall effects. Methods: A total of 11,395 participants from the Guangzhou Heart Study (GZHS) were followed up until 1 January 2020. Individual causes of death were obtained from the platform of the National Death Registry of China. The healthy lifestyle index (HLI) was established from seven dimensions of lifestyle, and lifestyle patterns were extracted from eight dimensions of lifestyle using principal component analysis (PCA). Hazard ratios (HRs) and 95% confidence intervals (95% CIs) were estimated using the Cox proportional hazard regression model. Results: During 35,837 person-years of follow-up, 184 deaths (1.61%) were observed, including 64 from cardiovascular disease. After adjustment for confounders, HLI was associated with a 50% (HR: 0.50, 95% CI: 0.25-0.99) reduced risk of all-cause mortality when comparing the high (6-7 lifestyle factors) with low (0-2 lifestyle factors) categories. Three lifestyle patterns were defined and labeled as pattern I, II, and III. Lifestyle pattern II with higher factor loadings of non-smoking and low-level alcohol drinking was associated with a decreased risk of all-cause mortality (HR: 0.63, 95% CI: 0.43-0.92, P -trend = 0.023) when comparing the high with low tertiles of pattern score, after adjustment for confounders. Every 1-unit increment of pattern II score was associated with a decreased risk (HR: 0.97, 95% CI: 0.95-0.99) of all-cause mortality. The other two patterns were not associated with all-cause mortality, and the association of cardiovascular mortality risk was observed with neither HLI nor any lifestyle pattern. Conclusion: The results suggest that the more dimensions of the healthy lifestyle the lower the risk of death, and adherence to the lifestyle pattern characterized with heavier loading of non-smoking and low-level alcohol drinking reduces the risk of all-cause mortality. The findings highlight the need to consider multi-dimensional lifestyles rather than one when developing health promotion strategies.

14.
Opt Lett ; 47(18): 4728-4731, 2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-36107073

RESUMO

We report on a Kerr-lens mode-locked Yb:YAlO3 laser generating soliton pulses as short as 24 fs at 1085 nm with an average output power of 186 mW and a pulse repetition rate of 87.5 MHz, representing the shortest pulses ever achieved from any mode-locked laser based on Yb3+-doped structurally ordered crystal. Optimized for power-scalable operation, the Yb:YAlO3 laser delivers 1.9 W at 1060 nm at the expense of a longer pulse duration of 44 fs, corresponding to a peak power of 462 kW and an optical efficiency of 43.2%.

15.
Zootaxa ; 5175(4): 463-477, 2022 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-36095351

RESUMO

A new species Andropromachus ynau sp. nov.. is described and the Chinese species of the moss-like stick insect genus Andropromachus are reviewed. An updated key to the known species of this genus is provided. Types of the new species are deposited in Yunnan Agricultural University (YNAU).


Assuntos
Briófitas , Neópteros , Animais , China , Humanos , Insetos , Universidades
16.
Front Immunol ; 13: 942862, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36091043

RESUMO

The morbidity and mortality of malaria are still high. Programmed cell death-1(PD-1) is an important co-inhibitory factor and CD8 T cells with PD-1 were reported to be exhausted cells. It remains unknown what the role of CD4 T cells expressing PD-1 is and what the upstream regulating molecules of PD-1 in CD4 T cells are. The C57BL/6 mice were injected with Plasmodium yoelii (P. yoelii) in this study. Expressions of PD-1, activation markers, and cytokines were tested. The differentially expressed genes between PD-1+/- CD4 T cells were detected by microarray sequencing. Western blot, chromatin immunoprecipitation (ChIP), siRNA, hypoxia inducible factor-1α (HIF-1α) inducer and inhibitor were used to explore PD-1's upstream molecules, respectively. The proportions of PD-1+ CD4 T cells increased post P. yoelii infection. PD-1+ CD4 T cells expressed more activated surface markers and could produce more cytokines. Nuclear factor of activated T cells 1 (NFATc1) was found to be a key transcription factor to induce PD-1 expression after infection. Both the inducer and the inhibitor of HIF-1α could change the expressions of NFATc1 and PD-1 in vivo and in vitro, respectively. Taken together, P. yoelii infection induced NFATc1 expression by HIF-1α. The highly expressed NFATc1 entered the nucleus and initiated PD-1 expression. PD-1+ CD4 T cells appeared to be more activated and could secrete more cytokines to regulate the host's immune responses against malaria.


Assuntos
Linfócitos T CD4-Positivos , Subunidade alfa do Fator 1 Induzível por Hipóxia , Malária , Fatores de Transcrição NFATC , Plasmodium yoelii , Receptor de Morte Celular Programada 1 , Animais , Linfócitos T CD4-Positivos/imunologia , Citocinas/imunologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/imunologia , Malária/genética , Malária/imunologia , Malária/parasitologia , Camundongos , Camundongos Endogâmicos C57BL , Fatores de Transcrição NFATC/genética , Fatores de Transcrição NFATC/imunologia , Receptor de Morte Celular Programada 1/genética , Receptor de Morte Celular Programada 1/imunologia , Transdução de Sinais
17.
Microbiol Res ; 265: 127195, 2022 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-36126492

RESUMO

Fusarium verticillioides is a key maize pathogen and produces fumonisins, a group of mycotoxins detrimental to humans and animals. Unfortunately, our understanding on how this fungus interacts with maize to trigger mycotoxin biosynthesis is limited. We performed a systematic computational network-based analysis of large-scale F. verticillioides RNA-seq datasets to identify gene subnetwork modules associated with virulence and fumonisin regulation. F. verticillioides was inoculated on two different maize lines, moderately resistant line hybrid 33K44 and highly susceptible line maize inbred line B73, to generate time-course RNA-Seq data. Among the highly discriminative subnetwork modules, we identified a putative hub gene FvLCP1, which encodes a putative a type-D fungal LysM protein with a signal peptide, three LysM domains, and two chitin binding domains. FvLcp1 is a unique protein that harbors these domains amongst five representative Fusarium species. FvLcp1 is a secreted protein important for fumonisin production with the LysM domain playing a critical role. The chitin-binding domain was essential for in vitro chitin binding. Using Magnaporthe oryzae, we learned that FvLcp1 accumulates in appressoria, suggesting that FvLcp1 is involved in host recognition and infection. Full length FvLcp1 suppressed BAX-triggered plant cell death in Nicotiana benthamiana. This unique type-D LysM secreted protein with a chitin-binding domain in F. verticillioides was shown to be potentially involved in suppressing host cell death and promoting fumonisin biosynthesis while the pathogen colonizes maize kernels.

18.
mBio ; : e0201322, 2022 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-36043788

RESUMO

Lysine acetylation, a ubiquitous and dynamic regulatory posttranslational modification (PTM), affects hundreds of proteins across all domains of life. In bacteria, lysine acetylation can be found in many essential pathways, and it is also crucial for bacterial virulence. However, the biological significance of lysine acetylation events to bacterial virulence factors remains poorly characterized. In Streptococcus mutans, the acetylome profiles help identify several lysine acetylation sites of lactate dehydrogenase (LDH), which catalyzes the conversion of pyruvate to lactic acid, causing the deterioration of teeth. We investigated the regulatory mechanism of LDH acetylation and characterized the effect of LDH acetylation on its function. We overexpressed the 15 Gcn5 N-acetyltransferases (GNAT) family members in S. mutans and showed that the acetyltransferase ActA impaired its acidogenicity by acetylating LDH. Additionally, enzymatic acetyltransferase reactions demonstrated that purified ActA could acetylate LDH in vitro, and 10 potential lysine acetylation sites of LDH were identified by mass spectrometry, 70% of which were also detected in vivo. We further demonstrated that the lysine acetylation of LDH inhibited its enzymatic activity, and a subsequent rat caries model showed that ActA impaired the cariogenicity of S. mutans. Collectively, we demonstrated that ActA, the first identified and characterized acetyltransferase in S. mutans, acetylated the LDH enzymatically and inhibited its enzymatic activity, thereby providing a starting point for the further analysis of the biological significance of lysine acetylation in the virulence of S. mutans. IMPORTANCE Lysine acetylation, a dynamic regulatory posttranslational modification, remains poorly characterized in bacteria. Hundreds of proteins have been identified to be acetylated in bacteria, with advances made in acetylome analyses. However, the regulatory mechanisms and functional significance of the majority of these acetylated proteins remain unclear. We analyzed the acetylome profiles of Streptococcus mutans and found that lactate dehydrogenase (LDH) contains several lysine acetylation sites. We also demonstrated that the acetyltransferase ActA, a member of the Gcn5 N-acetyltransferases (GNAT) family in S. mutans, acetylated LDH, inhibited its enzymatic ability to catalyze the conversion of pyruvate to lactic acid, and impaired its cariogenicity in a rat caries model. Therefore, LDH acetylation might be a potential target that can be exploited in the design of novel therapeutics to prevent dental caries.

19.
Sensors (Basel) ; 22(16)2022 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-36015702

RESUMO

The development of quantum radar technology presents a challenge to stealth targets, so it is necessary to study the quantum detection probability. In this study, an analytical expression of the quantum radar cross section (QRCS) for complex targets is presented. Based on this QRCS expression, a calculation method for the detection probability for quantum radar is creatively proposed. Moreover, a self-designed flying-wing stealth aircraft is adopted to obtain the detection probability distributions of the conventional radar and the quantum radar in different directions. As revealed by the result of this study, the detection probabilities of the quantum radar and the conventional radar are significantly different, and the detection probability of the quantum radar has obvious advantages in most regions with a certain distance.

20.
JACS Au ; 2(8): 1800-1810, 2022 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-36032530

RESUMO

Plasma-catalytic CO2 hydrogenation is a complex chemical process combining plasma-assisted gas-phase and surface reactions. Herein, we investigated CO2 hydrogenation over Pd/ZnO and ZnO in a tubular dielectric barrier discharge (DBD) reactor at ambient pressure. Compared to the CO2 hydrogenation using Plasma Only or Plasma + ZnO, placing Pd/ZnO in the DBD almost doubled the conversion of CO2 (36.7%) and CO yield (35.5%). The reaction pathways in the plasma-enhanced catalytic hydrogenation of CO2 were investigated by in situ Fourier transform infrared (FTIR) spectroscopy using a novel integrated in situ DBD/FTIR gas cell reactor, combined with online mass spectrometry (MS) analysis, kinetic analysis, and emission spectroscopic measurements. In plasma CO2 hydrogenation over Pd/ZnO, the hydrogenation of adsorbed surface CO2 on Pd/ZnO is the dominant reaction route for the enhanced CO2 conversion, which can be ascribed to the generation of a ZnO x overlay as a result of the strong metal-support interactions (SMSI) at the Pd-ZnO interface and the presence of abundant H species at the surface of Pd/ZnO; however, this important surface reaction can be limited in the Plasma + ZnO system due to a lack of active H species present on the ZnO surface and the absence of the SMSI. Instead, CO2 splitting to CO, both in the plasma gas phase and on the surface of ZnO, is believed to make an important contribution to the conversion of CO2 in the Plasma + ZnO system.

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