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1.
Breast Cancer Res ; 26(1): 103, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38890750

RESUMO

BACKGROUND: Triple-negative breast cancer (TNBC) represents a highly aggressive subset of breast malignancies characterized by its challenging clinical management and unfavorable prognosis. While TFAP2A, a member of the AP-2 transcription factor family, has been implicated in maintaining the basal phenotype of breast cancer, its precise regulatory role in TNBC remains undefined. METHODS: In vitro assessments of TNBC cell growth and migratory potential were conducted using MTS, colony formation, and EdU assays. Quantitative PCR was employed to analyze mRNA expression levels, while Western blot was utilized to evaluate protein expression and phosphorylation status of AKT and ERK. The post-transcriptional regulation of TFAP2A by miR-8072 and the transcriptional activation of SNAI1 by TFAP2A were investigated through luciferase reporter assays. A xenograft mouse model was employed to assess the in vivo growth capacity of TNBC cells. RESULTS: Selective silencing of TFAP2A significantly impeded the proliferation and migration of TNBC cells, with elevated TFAP2A expression observed in breast cancer tissues. Notably, TNBC patients exhibiting heightened TFAP2A levels experienced abbreviated overall survival. Mechanistically, TFAP2A was identified as a transcriptional activator of SNAI1, a crucial regulator of epithelial-mesenchymal transition (EMT) and cellular proliferation, thereby augmenting the oncogenic properties of TFAP2A in TNBC. Moreover, miR-8072 was unveiled as a negative regulator of TFAP2A, exerting potent inhibitory effects on TNBC cell growth and migration. Importantly, the tumor-suppressive actions mediated by the miR-8072/TFAP2A axis were intricately associated with the attenuation of AKT/ERK signaling cascades and the blockade of EMT processes. CONCLUSIONS: Our findings unravel the role and underlying molecular mechanism of TFAP2A in driving tumorigenesis of TNBC. Targeting the TFAP2A/SNAI1 pathway and utilizing miR-8072 as a suppressor represent promising therapeutic strategies for treating TNBC.


Assuntos
Movimento Celular , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , MicroRNAs , Fatores de Transcrição da Família Snail , Fator de Transcrição AP-2 , Neoplasias de Mama Triplo Negativas , Fator de Transcrição AP-2/metabolismo , Fator de Transcrição AP-2/genética , Humanos , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/patologia , Neoplasias de Mama Triplo Negativas/metabolismo , Neoplasias de Mama Triplo Negativas/mortalidade , MicroRNAs/genética , Fatores de Transcrição da Família Snail/metabolismo , Fatores de Transcrição da Família Snail/genética , Feminino , Animais , Camundongos , Linhagem Celular Tumoral , Movimento Celular/genética , Transição Epitelial-Mesenquimal/genética , Regulação para Baixo , Ensaios Antitumorais Modelo de Xenoenxerto
2.
J Virol ; 97(4): e0181422, 2023 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-36939341

RESUMO

Rift Valley fever virus (RVFV) is a mosquito-borne bunyavirus that causes severe and potentially fatal hemorrhagic fever in humans. Autophagy is a self-degradative process that can restrict viral replication at multiple infection steps. In this study, we evaluated the effects of RVFV-triggered autophagy on viral replication and immune responses. Our results showed that RVFV infection triggered autophagosome formation and induced complete autophagy. Impairing autophagy flux by depleting autophagy-related gene 5 (ATG5), ATG7, or sequestosome 1 (SQSTM1) or treatment with autophagy inhibitors markedly reduced viral RNA synthesis and progeny virus production. Mechanistically, our findings demonstrated that the RVFV nucleoprotein (NP) C-terminal domain interacts with the autophagy receptor SQSTM1 and promotes the SQSTM1-microtubule-associated protein 1 light chain 3 B (LC3B) interaction and autophagy. Deletion of the NP C-terminal domain impaired the interaction between NP and SQSTM1 and its ability to trigger autophagy. Notably, RVFV-triggered autophagy promoted viral infection in macrophages but not in other tested cell types, including Huh7 hepatocytes and human umbilical vein endothelial cells, suggesting cell type specificity of this mechanism. It was further revealed that RVFV NP-triggered autophagy dampens antiviral innate immune responses in infected macrophages to promote viral replication. These results provide novel insights into the mechanisms of RVFV-triggered autophagy and indicate the potential of targeting the autophagy pathway to develop antivirals against RVFV. IMPORTANCE We showed that RVFV infection induced the complete autophagy process. Depletion of the core autophagy genes ATG5, ATG7, or SQSTM1 or pharmacologic inhibition of autophagy in macrophages strongly suppressed RVFV replication. We further revealed that the RVFV NP C-terminal domain interacted with SQSTM1 and enhanced the SQSTM1/LC3B interaction to promote autophagy. RVFV NP-triggered autophagy strongly inhibited virus-induced expression of interferon-stimulated genes in infected macrophages but not in other tested cell types. Our study provides novel insights into the mechanisms of RVFV-triggered autophagy and highlights the potential of targeting autophagy flux to develop antivirals against this virus.


Assuntos
Autofagia , Imunidade Inata , Nucleoproteínas , Vírus da Febre do Vale do Rift , Imunidade Inata/imunologia , Vírus da Febre do Vale do Rift/imunologia , Nucleoproteínas/imunologia , Nucleoproteínas/metabolismo , Autofagia/imunologia , Replicação Viral , Linhagem Celular , Febre do Vale de Rift/imunologia , Humanos , Animais , Macrófagos/virologia
3.
Opt Express ; 31(17): 27381-27392, 2023 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-37710815

RESUMO

We propose an alternative scheme to achieve the cross-correlations between magnon and photon in a hybrid nonlinear system including two microwave cavities and one yttrium iron garnet (YIG) sphere, where two cavities nonlinearly interact and meanwhile one of cavities couples to magnon representing the collective excitation in YIG sphere via magnetic dipole interaction. Based on dispersive couplings between two cavities and between one cavity and magnon with the larger detunings, the nonlinear interaction occurs between the other cavity and magnon, which plays a crucial role in generating quantum correlations. By analyzing the second-order correlation functions via numerical simulations and analytical calculations, the remarkable nonclassical correlations are existent in such a system, where the magnon blockade and photon antibunching could be obtainable on demand. The scheme we present is focused on the magnon-photon cross-correlations in the weak coupling regime and relaxes the requirements of experimental conditions, which may have potential applications in quantum information processing in the hybrid system.

4.
J Virol ; 95(17): e0074721, 2021 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-34133897

RESUMO

The coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is bringing an unprecedented health crisis to the world. To date, our understanding of the interaction between SARS-CoV-2 and host innate immunity is still limited. Previous studies reported that SARS-CoV-2 nonstructural protein 12 (NSP12) was able to suppress interferon-ß (IFN-ß) activation in IFN-ß promoter luciferase reporter assays, which provided insights into the pathogenesis of COVID-19. In this study, we demonstrated that IFN-ß promoter-mediated luciferase activity was reduced during coexpression of NSP12. However, we could show NSP12 did not affect IRF3 or NF-κB activation. Moreover, IFN-ß production induced by Sendai virus (SeV) infection or other stimulus was not affected by NSP12 at mRNA or protein level. Additionally, the type I IFN signaling pathway was not affected by NSP12, as demonstrated by the expression of interferon-stimulated genes (ISGs). Further experiments revealed that different experiment systems, including protein tags and plasmid backbones, could affect the readouts of IFN-ß promoter luciferase assays. In conclusion, unlike as previously reported, our study showed SARS-CoV-2 NSP12 protein is not an IFN-ß antagonist. It also rings the alarm on the general usage of luciferase reporter assays in studying SARS-CoV-2. IMPORTANCE Previous studies investigated the interaction between SARS-CoV-2 viral proteins and interferon signaling and proposed that several SARS-CoV-2 viral proteins, including NSP12, could suppress IFN-ß activation. However, most of these results were generated from IFN-ß promoter luciferase reporter assay and have not been validated functionally. In our study, we found that, although NSP12 could suppress IFN-ß promoter luciferase activity, it showed no inhibitory effect on IFN-ß production or its downstream signaling. Further study revealed that contradictory results could be generated from different experiment systems. On one hand, we demonstrated that SARS-CoV-2 NSP12 could not suppress IFN-ß signaling. On the other hand, our study suggests that caution needs to be taken with the interpretation of SARS-CoV-2-related luciferase assays.


Assuntos
RNA-Polimerase RNA-Dependente de Coronavírus , Interferon beta , Regiões Promotoras Genéticas , SARS-CoV-2 , RNA-Polimerase RNA-Dependente de Coronavírus/genética , RNA-Polimerase RNA-Dependente de Coronavírus/metabolismo , Células HEK293 , Humanos , Fator Regulador 3 de Interferon/genética , Fator Regulador 3 de Interferon/metabolismo , Interferon beta/antagonistas & inibidores , Interferon beta/biossíntese , Interferon beta/genética , NF-kappa B/genética , NF-kappa B/metabolismo , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , SARS-CoV-2/genética , SARS-CoV-2/metabolismo
5.
Opt Express ; 30(15): 27346-27365, 2022 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-36236908

RESUMO

In scattering scenes, depth measurements are greatly distorted due to light scattering for Time-of-flight imaging. We propose a bispectral Time-of-flight system and phasor-based depth-recovery method to improve the quality of depth maps in scattering scenes. We reveal that the amplitude of scattered light is wavelength dependent while the phase measured is wavelength independent. The method uses bispectral measurements to nullify the effects of scattering components by calculating the amplitude ratio of scattering phasors. Experimental results demonstrate that the proposed method has a significant improvement in depth recovery with robustness and low computational cost.

6.
J Exp Bot ; 73(19): 6663-6677, 2022 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-35927220

RESUMO

Sclerotinia stem rot (SSR), caused by Sclerotinia sclerotiorum, is among the most devastating diseases in Brassica napus worldwide. Conventional breeding for SSR resistance in Brassica species is challenging due to the limited availability of resistant germplasm. Therefore, genetic engineering is an attractive approach for developing SSR-resistant Brassica crops. Compared with the constitutive promoter, an S. sclerotiorum-inducible promoter would avoid ectopic expression of defense genes that may cause plant growth deficits. In this study, we generated a S. sclerotiorum-inducible promoter. pBnGH17D7, from the promoter of B. napus glycosyl hydrolase 17 gene (pBnGH17). Specifically, 5'-deletion and promoter activity analyses in transgenic Arabidopsis thaliana plants defined a 189 bp region of pBnGH17 which was indispensable for S. sclerotiorum-induced response. Compared with pBnGH17, pBnGH17D7 showed a similar response upon S. sclerotiorum infection, but lower activity in plant tissues in the absence of S. sclerotiorum infection. Moreover, we revealed that the transcription factor BnTGA7 directly binds to the TGACG motif in pBnGH17D7 to activate BnGH17. Ultimately, pBnGH17D7 was exploited for engineering Sclerotinia-resistant B. napus via host-induced gene silencing. It induces high expression of siRNAs against the S. sclerotiorum pathogenic factor gene specifically during infection, leading to increased resistance.


Assuntos
Arabidopsis , Ascomicetos , Brassica napus , Brassica , Brassica napus/genética , Brassica napus/metabolismo , Doenças das Plantas/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Melhoramento Vegetal , Ascomicetos/fisiologia , Brassica/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Inativação Gênica
7.
Diabetes Metab Res Rev ; 38(1): e3477, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34041844

RESUMO

AIMS: Glycated albumin (GA) is a biomarker for short-term (2-3 weeks) glycaemic control. However, the predictive utility of GA for diabetes and prediabetes is largely uncharacterised. We aimed to investigate the relationships of baseline serum GA levels with incident diabetes and prediabetes. METHODS: This was a longitudinal cohort study involving 516 subjects without diabetes or prediabetes at baseline. Blood glucose levels were observed during follow-up. Hazard ratios (HRs) with 95% confidence intervals (CIs) were calculated using COX proportional hazard models. Receiver operating characteristic curves and areas under the curves (AUCs) were used to evaluate the discriminating abilities of glycaemic biomarkers and prediction models. RESULTS: During a 9-year follow-up, 51 individuals (9.88%) developed diabetes and 92 (17.83%) prediabetes. Unadjusted HRs (95% CI) for both diabetes and prediabetes increased proportionally with increasing GA levels in a dose-response manner. Multivariable-adjusted HRs (95% CI) for diabetes were significantly elevated from 1.0 (reference) to 5.58 (1.86-16.74). However, the trend was no longer significant for prediabetes after multivariable adjustment. AUCs for GA, fasting blood glucose (FBG) and 2-h postprandial blood glucose (2h-PBG) for predicting diabetes were 0.698, 0.655 and 0.725, respectively. The AUCs for GA had no significant differences compared with those for FBG (p = 0.376) and 2h-PBG (p = 0.552). Replacing FBG or 2h-PBG or both with GA in diabetes prediction models made no significant changes to the AUCs of the models. CONCLUSIONS: GA is of good prognostic utility in predicting diabetes. However, GA may not be a useful biomarker for predicting prediabetes.


Assuntos
Diabetes Mellitus Tipo 2 , Estado Pré-Diabético , Biomarcadores , Glicemia , Estudos de Coortes , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/epidemiologia , Hemoglobinas Glicadas/análise , Produtos Finais de Glicação Avançada , Humanos , Estudos Longitudinais , Estado Pré-Diabético/diagnóstico , Estado Pré-Diabético/epidemiologia , Estudos Retrospectivos , Albumina Sérica , Albumina Sérica Glicada
8.
Appl Opt ; 61(24): 7206-7217, 2022 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-36256341

RESUMO

The existence of nearby obstruction causes significant errors in depth sensing for time-of-flight cameras, namely multipath interference. A polarized time-of-flight system is established for multipath interference mitigation. Based on polarization cues and the phasor representation of time-of-flight imaging, the proposed method acquires depth maps in high accuracy when specular dominant obstruction is in path. Both rough and smooth targets are applicable in our approach even though they have distinct polarization characteristics. Several experiments with different types of targets and various obstructions confirm the effectiveness of our method qualitatively and quantitatively.

9.
Sensors (Basel) ; 22(9)2022 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-35590850

RESUMO

Due to the light scattered by atmospheric aerosols, the amplitude image contrast is degraded and the depth measurement is greatly distorted for time-of-flight (ToF) imaging in fog. The problem limits ToF imaging to be applied in outdoor settings, such as autonomous driving. To improve the quality of the images captured by ToF cameras, we propose a polarization phasor imaging method for image recovery in foggy scenes. In this paper, optical polarimetric defogging is introduced into ToF phasor imaging, and the degree of polarization phasor is proposed to estimate the scattering component. A polarization phasor imaging model is established, aiming at separating the target component from the signal received by ToF cameras to recover the amplitude and depth information. The effectiveness of this method is confirmed by several experiments with artificial fog, and the experimental results demonstrate that the proposed method significantly improves the image quality, with robustness in different thicknesses of fog.


Assuntos
Diagnóstico por Imagem , Tempo (Meteorologia) , Análise Espectral
10.
Sensors (Basel) ; 21(10)2021 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-34068306

RESUMO

Precise localization and pose estimation in indoor environments are commonly employed in a wide range of applications, including robotics, augmented reality, and navigation and positioning services. Such applications can be solved via visual-based localization using a pre-built 3D model. The increase in searching space associated with large scenes can be overcome by retrieving images in advance and subsequently estimating the pose. The majority of current deep learning-based image retrieval methods require labeled data, which increase data annotation costs and complicate the acquisition of data. In this paper, we propose an unsupervised hierarchical indoor localization framework that integrates an unsupervised network variational autoencoder (VAE) with a visual-based Structure-from-Motion (SfM) approach in order to extract global and local features. During the localization process, global features are applied for the image retrieval at the level of the scene map in order to obtain candidate images, and are subsequently used to estimate the pose from 2D-3D matches between query and candidate images. RGB images only are used as the input of the proposed localization system, which is both convenient and challenging. Experimental results reveal that the proposed method can localize images within 0.16 m and 4° in the 7-Scenes data sets and 32.8% within 5 m and 20° in the Baidu data set. Furthermore, our proposed method achieves a higher precision compared to advanced methods.

11.
BMC Genomics ; 20(1): 360, 2019 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-31072300

RESUMO

BACKGROUND: Toxigenic Vibrio cholerae serogroup O1 is the causative pathogen in the sixth and seventh cholera pandemics. Cholera toxin is the major virulent factor but other virulence and virulence-related factors play certain roles in the pathogenesis and survival in the host. Along with the evolution of the epidemic strains, the virulence-related genes also experience variation, gain and loss, and lead to genetic divergence in different strains. RESULTS: In this study, we analyzed the virulence-related gene profiles in the toxigenic serogroup O1 strains isolated from 1923 to 2015, the genomes of which were publicly available. The virulence-related genes of the V. cholerae O1 strains were annotated based on the Virulence Factors Database (VFDB). An average of 230.1 virulence-related genes per strain were identified; significant differences in the average numbers were found between the classical and El Tor biotypes, and increasing trends in the number of virulence-related genes along with the isolation years were observed in the El Tor biotype strains. A total of 176 homologs of virulence-related genes were found from these strains, of which 25 belonged to the core genes, suggesting their conservative and necessary roles in V. cholerae pathogenesis. We described the diversities of the homologs by defining gene sequence type, and illustrated its association with gene duplication; we found that gene duplication clearly increased the complexity of the gene sequence types in the core virulence-related genes. In addition, we provided virulence-related gene profiles whose genetic characteristic depend on the isolation years from the view of gene gain and loss, variation, gene duplication and gene sequence type number. CONCLUSIONS: Our study reveals the comprehensive variation dynamics of the virulence-related genes in toxigenic V. cholerae serogroup O1 during epidemics. The increasing trend for the virulence-related genes may suggest the evolutional advantage of strains by gaining virulence-related genes with diverse functional categories.


Assuntos
Proteínas de Bactérias/genética , Cólera/epidemiologia , Variação Genética , Sorogrupo , Vibrio cholerae O1/genética , Fatores de Virulência/genética , Cólera/microbiologia , Humanos , Filogenia , Vibrio cholerae O1/isolamento & purificação
12.
Appl Environ Microbiol ; 85(11)2019 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-30902862

RESUMO

The genus Shewanella comprises a group of marine-dwelling species with worldwide distribution. Several species are regarded as causative agents of food spoilage and opportunistic pathogens of human diseases. In this study, a standard multilocus sequence analysis (MLSA) based on six protein-coding genes (gyrA, gyrB, infB, recN, rpoA, and topA) was established as a rapid and accurate identification tool in 59 Shewanella type strains. This method yielded sufficient resolving power in regard to enough informative sites, adequate sequence divergences, and distinct interspecies branches. The stability of phylogenetic topology was supported by high bootstrap values and concordance with different methods. The reliability of the MLSA scheme was further validated by identical phylogenies and high correlations of genomes. The MLSA approach provided a robust system to exhibit evolutionary relationships in the Shewanella genus. The split network tree proposed twelve distinct monophyletic clades with identical G+C contents and high genetic similarities. A total of 86 tested strains were investigated to explore the population biology of the Shewanella genus in China. The most prevalent Shewanella species was Shewanella algae, followed by Shewanella xiamenensis, Shewanella chilikensis, Shewanella indica, Shewanella seohaensis, and Shewanella carassii The strains frequently isolated from clinical and food samples highlighted the importance of increasing the surveillance of Shewanella species. Based on the combined genetic, genomic, and phenotypic analyses, Shewanella upenei should be considered a synonym of S. algae, and Shewanella pacifica should be reclassified as a synonym of Shewanella japonicaIMPORTANCE The MLSA scheme based on six housekeeping genes (HKGs) (gyrA, gyrB, infB, recN, rpoA, and topA) is well established as a reliable tool for taxonomic, evolutionary, and population diversity analyses of the genus Shewanella in this study. The standard MLSA method allows researchers to make rapid, economical, and precise identification of Shewanella strains. The robust phylogenetic network of MLSA provides profound insight into the evolutionary structure of the genus Shewanella The population genetics of Shewanella species determined by the MLSA approach plays a pivotal role in clinical diagnosis and routine monitoring. Further studies on remaining species and genomic analysis will enhance a more comprehensive understanding of the microbial systematics, phylogenetic relationships, and ecological status of the genus Shewanella.


Assuntos
Evolução Biológica , Tipagem de Sequências Multilocus/métodos , Filogenia , Shewanella/classificação , Shewanella/genética , Shewanella/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Microbiologia de Alimentos , Genes Bacterianos/genética , Genes Essenciais/genética , Humanos , Fenótipo , RNA Ribossômico 16S/genética , Reprodutibilidade dos Testes , Análise de Sequência de DNA
13.
Int J Syst Evol Microbiol ; 69(3): 852-858, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30663957

RESUMO

Eight swarming motile bacteria were isolated from food and clinical samples in China. Cells were Gram-stain-negative, facultatively anaerobic and rod-shaped (0.5-0.8×1.0-3.0 µm) with hairlike pili and flagella. The 16S rRNA and partial rpoB housekeeping gene sequence analyses indicated that the strains belong to the genus Proteusin the family Enterobacteriaceae. Of the eight strains studied, seven and a single isolate formed two separate clades in the phylogeny of Proteusspecies, indicating two separate species. Both the in silico DNA-DNA hybridization and the average nucleotide identity values between these two groups and to the type strains of the genus Proteuswere below the recommended threshold for signifying their candidature as two separate species. The DNA G+C contents of strains TJ1636T and FJ2001126-3T were 37.8 and 38.1 mol%, respectively. The major cellular fatty acids of the two novel type strains were C16:0, cyclo C17:0, summed feature 3 and summed feature 8. The results supported that the strains belong to different taxonomic positions in the genus Proteus. The isolates were named Proteus faecis sp. nov., with type strain TJ1636T (=DSM 106180T=GDMCC 1.1245T), and Proteuscibi sp. nov., with type strain FJ2001126-3T (=DSM 106178T =GDMCC 1.1244T).


Assuntos
Fezes/microbiologia , Microbiologia de Alimentos , Filogenia , Proteus/classificação , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Humanos , Hibridização de Ácido Nucleico , Proteus/isolamento & purificação , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
14.
Plant Cell Rep ; 38(5): 545-558, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30706138

RESUMO

KEY MESSAGE: Abnormal tapetum degradation and anther development in cytoplasmic male sterility SaNa-1A are the main reasons for the anther abortion. SaNa-1A is a novel cytoplasmic male sterility (CMS) line of Brassica napus derived from somatic hybrids of B. napus-Sinapis alba, and SaNa-1B is the corresponding maintainer line. Ultrastructural comparison between developing anthers of sterile and maintainer lines revealed abnormal subcellular structure of pollen mother cells (PMCs) in the CMS line. The PMC volume and size of nucleus and nucleolus in the CMS line were smaller than those in the maintainer line. The abnormal tapetum cell development and delayed tapetum degradation inhibited microspore development. Finally, anther abortion in the CMS line occurred. Physiological and biochemical analyses of developing anthers and mitochondria revealed that over-accumulation of reactive oxygen species (ROS) in the SaNa-1A and deficiency in antioxidant enzyme system aggravated the oxidization of membrane lipids, resulting in malondialdehyde (MDA) accumulation in anthers. High MDA content in the CMS line was toxic to the cells. ROS accumulation in SaNa-1A also affected anther development. Abnormal structure and function of terminal oxidase, which participates in the electron transport chain of mitochondrial membrane, were observed and affected the activity of cytochrome c oxidase and F1F0-ATPase, which inhibited ATP biosynthesis. Proline deficiency in SaNa-1A also affected anther development. Few hybridization signals of programmed cell death (PCD) in tetrads of SaNa-1A were identified using TdT-mediated dUTP Nick-End Labeling assay. PCD was not obvious in tapetum cells of SaNa-1A until the unicellular stage. These results validated the cytological differences mentioned above, and proved that abnormal tapetum degradation and anther development in SaNa-1A were the main reasons for the anther abortion.


Assuntos
Brassica napus/metabolismo , Citoplasma/metabolismo , Brassica napus/fisiologia , Metabolismo Energético/fisiologia , Regulação da Expressão Gênica de Plantas/genética , Regulação da Expressão Gênica de Plantas/fisiologia , Infertilidade das Plantas/fisiologia , Espécies Reativas de Oxigênio/metabolismo
15.
Int J Syst Evol Microbiol ; 68(4): 1390-1395, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29509133

RESUMO

Two strains of Gram-stain-negative, facultatively anaerobic short-rod bacteria were recovered from two different food samples in Ma'anshan city, Anhui province, China in 2008. The bacteria were characterized in a polyphasic taxonomic study that included phenotypic, phylogenetic and genotypic methodologies. Phylogenetic analysis of the 16S rRNA gene demonstrated that the two strains belonged to the genus Proteus and were most similar to Proteus vulgaris ATCC 29905T with a score of 99.7 %. Phylogenetic analysis of the rpoB gene placed the two strains into a cluster with a distinctly interspecies phylogenetic branch that was clearly separated from six type strains of the genus Proteus, with the most closely related species being Proteus mirabilis ATCC 29906T. In silico genomic comparisons, including in silico DNA-DNA hybridization (isDDH) and average nucleotide identity (ANI) analysis showed that the representative strain, 08MAS0041T, and all six Proteus species share less than 70 % isDDH and have a 95 % ANI cutoff level, supporting the designation of the two strains as a novel species of the genus Proteus. The predominant cellular fatty acids of strain 08MAS0041T were C16 : 0 (24.8 %), C16 : 1ω7c/16 : 1ω6c (16.5 %), C18 : 1ω6c/C18 : 1ω7c (14.5 %), C17 : 0 cyclo (12.6 %) and C16 : 1iso I/C14 : 0 3-OH (10.6 %). The analysis of biochemical, phylogenetic and genomic data confirmed that the two strains were clearly different from all recognized species of the genus Proteus and represent a novel Proteus species, for which the name Proteus alimentorum sp. nov. is proposed. The type strain is 08MAS0041T (=DSM 104685T=CGMCC 1.15939T).


Assuntos
Filogenia , Proteus/classificação , Carne Vermelha/microbiologia , Alimentos Marinhos/microbiologia , Animais , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Nephropidae , Hibridização de Ácido Nucleico , Proteus/genética , Proteus/isolamento & purificação , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Suínos
16.
Int J Syst Evol Microbiol ; 68(2): 552-557, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29297845

RESUMO

A Gram-negative, facultatively anaerobic bacillus, strain 08MAS2615T, was isolated from the flesh of a pigeon specimen collected in Ma'anshan, Anhui province, China. Phylogenetic analysis of 16S rRNA gene sequences confirmed that strain 08MAS2615T belonged to the genus Proteus, and formed an independent branch which was clearly separated from the other six known species of Proteus. Strain 08MAS2615T was more closely related to Proteus vulgaris ATCC 29905T and Proteus penneri NCTC 12737T than other Proteus species. Similar independent phylogenetic results were obtained using rpoB gene sequence analysis, whereas strain 08MAS2615T clustered near the species of Proteus cibarius JS9T and Proteus terrae N5/687T. Furthermore, the genome-wide core-single nucleotide polymorphism-based phylogenetic tree confirmed that strain 08MAS2615T formed a monophyletic and robust clade. Based on whole-genome sequences, the range of in silico DNA-DNA hybridization and average nucleotide identity between strain 08MAS2615T and the six Proteus species were 25.5-48.8 % and 82.8-92.9 %, respectively, less than the proposed cutoff level for species delineation, i.e. 70 and 95 %. In addition, the major cellular fatty acid profile of strain 08MAS2615T was C14 : 0 (12.4 %), C16 : 0 (23.8 %), C17 : 0cyclo (14.4 %), summed feature 2 (C16 : 1iso I/C14 : 0 3-OH) (11.0 %), summed feature 3 (C16 : 1ω7c/16 : 1ω6c) (18.5 %) and summed feature 8 (C18 : 1ω6c) (18.6 %). On the basis of these results, strain 08MAS2615T represents a novel species of the genus Proteus, for which the name Proteuscolumbae sp. nov. is proposed with strain 08MAS2615T (=DSM 104686T=CGMCC 1.15982T) designated as the species type strain.


Assuntos
Columbidae/microbiologia , Filogenia , Proteus/classificação , Animais , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Genes Bacterianos , Hibridização de Ácido Nucleico , Proteus/genética , Proteus/isolamento & purificação , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
17.
Int J Syst Evol Microbiol ; 68(4): 1146-1152, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29458501

RESUMO

A Gram-stain-negative, facultatively anaerobic strain, designated FJ201301T, was isolated from aquaculture water collected from Fujian province, China. Phylogenetic analysis of 16S rRNA gene sequences indicated that strain FJ201301T belonged to the genus Vibrio, formed a distinct cluster with Vibriocincinnatiensis ATCC 35912T and shared the highest similarity with Vibriosalilacus CGMCC 1.12427T. A 15 bp insertion found in the 16S rRNA gene was a significant marker that distinguished strain FJ201301T from several phylogenetic neighbours (e.g. V. cincinnatiensis). Multilocus sequence analysis of eight genes (ftsZ, gapA, gyrB, mreB, pyrH, recA, rpoA and topA; concatenated 4135 bp sequence) showed that, forming a long and independent phylogenetic branch, strain FJ201301T clustered with V. cincinnatiensis ATCC 35912T, Vibrioinjenensis KCTC 32233T and Vibriometschnikovii CIP 69.14T clearly separated from V. salilacus CGMCC 1.12427T. Furthermore, the highest in silico DNA-DNA hybridization and average nucleotide identity values between strain FJ201301T and the closest related species were 26.3 and 83.1 % with V. cincinnatiensis ATCC 35912T, less than the proposed cutoff levels for species delineation, i.e. 70 and 95 %, respectively. Biochemical, sequence and genomic analysis suggested the designation of strain FJ201301T representing a novel species of the genus Vibrio, for which the name Vibrio fujianensis sp. nov. is proposed. The type strain is FJ201301T (=DSM 104687T=CGMCC 1.16099T).


Assuntos
Aquicultura , Filogenia , Vibrio/classificação , Microbiologia da Água , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Genes Bacterianos , Tipagem de Sequências Multilocus , Hibridização de Ácido Nucleico , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vibrio/genética , Vibrio/isolamento & purificação
18.
BMC Infect Dis ; 18(1): 454, 2018 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-30185170

RESUMO

BACKGROUND: Members of Shewanella species are opportunistic pathogens that are found in marine environments. Currently more than sixty species have been identified, whereas the most commonly clinical cases associated with Shewanella species have involved only two species, i.e., S. algae and S. putrefaciens. We present two cases of pulmonary and bloodstream infections caused by two rare Shewanella spp. strains from patients of gastrointestinal cancer. CASE PRESENTATION: Two male patients with a history of gastrointestinal cancer presented to hospital with pulmonary and bloodstream infections, respectively. The infective pathogens of both cases were primarily isolated and identified as Shewanella algae (case I) and Shewanella putrefaciens (case II) by phenotypic features and VITEK 2 system, but they were further confirmed as Shewanella haliotis and Shewanella upenei by 16S rRNA gene sequence analysis. The major bacterial composition of the bronchoalveolar lavage in case I was also identified as Shewanella by 16S rRNA amplicon sequencing analysis. Antimicrobial susceptibility testing showed that the two strains had broad susceptibility, but S. haliotis in the case I was resistant to ciprofloxacin and levofloxacin and S. upenei in the case II was intermediate to imipenem, piperacillin/tazobactam and ciprofloxacin. CONCLUSIONS: To the best of our knowledge, this is the first cases of the pulmonary and bloodstream infections caused by Shewanella spp. from clinical patients in mainland China. Shewanella as a potential pathogen in China should not be ignored.


Assuntos
Neoplasias Esofágicas/diagnóstico , Infecções por Bactérias Gram-Negativas/diagnóstico , Shewanella/isolamento & purificação , Neoplasias Gástricas/diagnóstico , Idoso , Antibacterianos/farmacologia , Líquido da Lavagem Broncoalveolar/microbiologia , China , Neoplasias Esofágicas/complicações , Infecções por Bactérias Gram-Negativas/complicações , Infecções por Bactérias Gram-Negativas/microbiologia , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Filogenia , RNA Ribossômico 16S/genética , Shewanella/classificação , Shewanella/efeitos dos fármacos , Shewanella/genética , Neoplasias Gástricas/complicações
19.
Appl Opt ; 57(16): 4649-4658, 2018 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-29877374

RESUMO

Targeting star-like water surface clutter, a clutter suppression method based on infrared polarization information is proposed. First, the clutter is suppressed from a global perspective using infrared polarization imaging technology, and a basic clutter-suppressed image is obtained. Then, using the Reed-Xiaoli anomaly detection algorithm, the remaining clutter positions in the basic image are determined from the polarization intensity image and basic image. Finally, an image filtering algorithm is utilized to further suppress the remaining clutter in the basic image. In experiments, the proposed method can not only improve the signal-to-clutter ratio as much as 152%, but also preserve the target information and background texture features effectively, indicating clear superiority of our method over existing clutter suppression algorithms. Clutter suppression and target detail preservation can enhance observer understanding of a scene significantly, so this method is applied to the detection and recognition of targets on the water surface.

20.
Int J Mol Sci ; 19(9)2018 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-30208656

RESUMO

Targeted genome editing is a desirable means of basic science and crop improvement. The clustered, regularly interspaced, palindromic repeat (CRISPR)/Cas9 (CRISPR-associated 9) system is currently the simplest and most commonly used system in targeted genomic editing in plants. Single and multiplex genome editing in plants can be achieved under this system. In Arabidopsis, AtWRKY11 and AtWRKY70 genes were involved in JA- and SA-induced resistance to pathogens, in rapeseed (Brassica napus L.), BnWRKY11 and BnWRKY70 genes were found to be differently expressed after inoculated with the pathogenic fungus, Sclerotinia sclerotiorum (Lib.) de Bary. In this study, two Cas9/sgRNA constructs targeting two copies of BnWRKY11 and four copies of BnWRKY70 were designed to generate BnWRKY11 and BnWRKY70 mutants respectively. As a result, twenty-two BnWRKY11 and eight BnWRKY70 independent transformants (T0) were obtained, with the mutation ratios of 54.5% (12/22) and 50% (4/8) in BnWRKY11 and BnWRKY70 transformants respectively. Eight and two plants with two copies of mutated BnWRKY11 and BnWRKY70 were obtained respectively. In T1 generation of each plant examined, new mutations on target genes were detected with high efficiency. The vast majority of BnWRKY70 mutants showed editing in three copies of BnWRKY70 in examined T1 plants. BnWRKY70 mutants exhibited enhanced resistance to Sclerotinia, while BnWRKY11 mutants showed no significant difference in Sclerotinia resistance when compared to non-transgenic plants. In addition, plants that overexpressed BnWRKY70 showed increased sensitivity when compared to non-transgenic plants. Altogether, our results demonstrated that BnWRKY70 may function as a regulating factor to negatively control the Sclerotinia resistance and CRISPR/Cas9 system could be used to generate germplasm in B. napus with high resistance against Sclerotinia.


Assuntos
Brassica napus/genética , Sistemas CRISPR-Cas , Edição de Genes , Doenças das Plantas/genética , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas/genética , Fatores de Transcrição/genética , Ascomicetos/fisiologia , Resistência à Doença , Regulação da Expressão Gênica de Plantas , Genoma de Planta , Mutagênese , Mutação , Doenças das Plantas/microbiologia
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