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1.
J Sci Food Agric ; 102(1): 147-155, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34057213

RESUMO

BACKGROUND: Bacterial community successions were surveyed during the processing stages of sugar production using high-throughput sequencing methods. Furthermore, the correlation between bacterial community and nitrate/nitrite content in beet sugar processing were investigated. RESULTS: In an analysis of the V3-V4 region of the 16S rDNA gene, 254 122 effective sequences were obtained from samples, which included sugar beet, cossettes, diffusion juice, second-phase diffusion juice, light juice and thick juice. The results showed that dominant genera included Pantoea, Pseudomonas, Leuconostoc and Burkholderia. Moreover, significant changes in bacterial communities were observed in samples. Regarding the relevant nitrogen metabolic potential, this study revealed communities with the ability for nitrate and nitrite metabolism. Furthermore, a shaking experiment involving diffusion juice and second-phase diffusion juice was performed, and results showed that the nitrate level declined 73% and 98% in 36 h, respectively. These results suggested that the bacterial communities contribute to nitrate and nitrite transformation. CONCLUSION: This study illustrated that the bacterial communities and their specific effects on the formation of nitrate and nitrite during beet sugar processing. The results presented the basic concept involving the nitrate- and nitrite-forming pathways directly related to the mechanism of bacterial community growth. This study could facilitate an understanding of the correlation between nitrite content and microorganisms to guide beet sugar manufacturers regarding the control of nitrite and nitrate content. © 2021 Society of Chemical Industry.


Assuntos
Bactérias/metabolismo , Beta vulgaris/química , Nitratos/análise , Nitritos/análise , Tubérculos/microbiologia , Açúcares/isolamento & purificação , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Beta vulgaris/microbiologia , Biotransformação , Manipulação de Alimentos , Sequenciamento de Nucleotídeos em Larga Escala , Nitratos/metabolismo , Nitritos/metabolismo , Tubérculos/química , Açúcares/química
2.
Artigo em Inglês | MEDLINE | ID: mdl-34824588

RESUMO

Working memory (WM), a central component of general cognition, plays an essential role in human beings' daily lives. WM impairments often occur in psychiatric, neurodegenerative, and neurodevelopmental disorders, mainly presenting as loss of high-load WM. In previous research, electroacupuncture (EA) has been shown to be an effective treatment for cognitive impairments. Frequency parameters are an important factor in therapeutic results, but the optimal frequency parameters of EA have not yet been identified. In this study, we chose theta-EA (θ-EA; 6 Hz) and gamma-EA (γ-EA; 40 Hz), corresponding to the transcranial alternating-current stimulation (tACS) frequency parameters at the Baihui (DU20) and Shenting (DU24) acupoints, in order to compare the effects of different EA frequencies on WM. We evaluated WM performance using visual 1-back, 2-back, and 3-back WM tasks involving digits. Each participant (N = 30) attended three different sessions in accordance with a within-subject crossover design. We performed θ-EA, γ-EA, and sham-EA in a counterbalanced order, conducting the WM task both before and after intervention. The results showed that d-prime (d') under all three stimulation conditions had no significance in the 1-back and 2-back tasks. However, in the 3-back task, there was a significant improvement in d' after intervention compared to d' before intervention under θ-EA (F [1, 29] = 22.64; P < 0.001), while we saw no significant difference in the γ-EA and sham-EA groups. Reaction times for hits (RT-hit) under all three stimulation conditions showed decreasing trends in 1-, 2-, and 3-back tasks but without statistically significant differences. These findings suggest that the application of θ-EA might facilitate high-load WM performance.

3.
Artigo em Inglês | MEDLINE | ID: mdl-34727034

RESUMO

The non-stationary characteristics of surface electromyography (sEMG) and possible adverse variations in real-world conditions make it still an open challenge to realize robust myoelectric control (MEC) for multifunctional prostheses. Variable muscle contraction level is one of the handicaps that may degrade the performance of MEC. In this study, we proposed a force-invariant intent recognition method based on muscle synergy analysis (MSA) in the setting of three self-defined force levels (low, medium, and high). Specifically, a fast matrix factorization algorithm based on alternating non-negativity constrained least squares (NMF/ANLS) was chosen to extract task-specific synergies associated with each of six hand gestures in the training stage; while for the testing samples, we used the non-negative least square (NNLS) method to estimate neural commands for movement classification. The performance of proposed method was compared with conventional pattern recognition (PR) method consisting of LDA (linear discrimination analysis) classifier and representative features in three offline evaluation scenarios. Statistical tests on ten able-bodied subjects revealed no significant difference in intra-force-level (p = 0.353) and multi-force-level (p = 0.695) accuracy; But the synergy-based method performed significantly better than conventional PR-based method under inter-force-level conditions (p < 0.05). Similar results were observed for nine amputee subjects though there was a drop in the classification accuracy. This study was the first to concurrently demonstrate the robustness and predictive power of task-specific synergies under variant force levels and explore their potential for reliable intent recognition against force variation. Although the online performance is yet to be demonstrated, the proposed method is characterized by simple training procedure and acceptable computational efficiency, which would potentially provide an alternative approach for the development of clinically viable prostheses and rehabilitation robots driven by sEMG.


Assuntos
Membros Artificiais , Gestos , Eletromiografia , Humanos , Movimento , Reconhecimento Automatizado de Padrão
4.
Trials ; 22(1): 837, 2021 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-34819130

RESUMO

BACKGROUND: People with post-stroke aphasia commonly receive speech-language therapy (SLT) when they are admitted to hospitals. Commonly, these patients reported communication difficulties in in-patient settings. Augmentative and alternative communication (AAC) has been reported as an effective treatment approach to improve communication effectiveness, language performance, decreasing depression, and improving quality of life for this population. However, little evidence has demonstrated the use of AAC intervention (AACT) in early recovery from people with post-stroke aphasia in in-patient rehabilitation settings for improving these patients' communication effectiveness. The pilot randomized controlled trial (RCT) will explore the effectiveness and feasibility of including AACT in regular SLT for in-patient people with post-stroke aphasia. METHOD: This pilot RCT is a single-blind, randomized controlled trial with two parallel groups. Both groups receive a 1-h treatment session, including either both AACT and SLT or SLT only for ten consecutive days. We aim to include 22 in-patient participants with post-stroke aphasia in each group. Participants will be assessed at pre- and post-intervention and 2 weeks after intervention. The primary outcomes are the ability of communication measured by the communication of basic needs subtest in the Functional Assessment of Communication Skills for Adult (FACS) and the overall language performance measured by the Chinese Standard Aphasia Battery (ABC). The secondary outcomes include a 10-min conversation, the 10-item Hospital version of the Stroke Aphasic Depression Questionnaire (SADQH-10), the Stroke-Specific Quality of Life Scale (SS-QOL), and a patient and caregiver satisfaction questionnaire. DISCUSSION: This pilot RCT will contribute to new scientific evidence to the field of aphasia rehabilitation in early recovery during the in-patient period. The paper describes the trial, which will explore the effect of combining AACT and SLT and SLT only, our choice of primary and secondary outcome measures, and proposed analyses. The study results will provide information for implementing AACT in the regular in-patient SLT of future RCTs. TRIAL REGISTRATION: Chinese Clinical Trial Registry database (ChiCTR) ChiCTR2000028870 . Registered on 5 January 2020.

5.
Br J Haematol ; 2021 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-34664256

RESUMO

Diffuse large B-cell lymphoma (DLBCL) is a highly heterogenous malignancy, early identification of patients for relapse remains challenging. The potential to non-invasively monitor tumour evolutionary dynamics of DLBCL needs to be further established. In the present study, 17 tumour biopsy and 38 plasma samples from 38 patients with high-intermediate/high-risk DLBCL were evaluated at baseline. Longitudinal blood samples were also collected during therapy. Circulating tumour DNA (ctDNA) was analysed using targeted sequencing based on a gene panel via a recently developed methodology, circulating single-molecule amplification and re-sequencing technology (cSMART). We found that the most frequently mutated genes were tumour protein p53 (TP53; 42·1%), histone-lysine N-methyltransferase 2D (KMT2D; 28·9%), caspase recruitment domain family member 11 (CARD11; 21·1%), cAMP response element-binding protein binding protein (CREBBP; 15·8%), ß2 -microglobulin (B2M; 15·8%), and tumour necrosis factor alpha-induced protein 3 (TNFAIP3; 15·8%). The mutation profiles between ctDNA and matched tumour tissue showed good concordance; however, more mutation sites were detected in ctDNA samples. Either TP53 or B2M mutations before treatment predicted poor prognosis. Analysis of dynamic blood samples confirmed the utility of ctDNA for the real-time assessment of treatment response and revealed that the increases in ctDNA levels and changes in KMT2D mutation status could be useful predictors of disease progression. Our present results suggest that ctDNA is a promising method for the detection of mutation spectrum and serves as a biomarker for disease monitoring and predicting clinical recurrence.

6.
Sensors (Basel) ; 21(17)2021 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-34502606

RESUMO

Planetary gearboxes are the key components of large equipment, such as wind turbines, shield machines, etc. The operating state of the planetary gearbox is related to the safety of the equipment as a whole, and its feature extraction technology is essential. In assessing the problem of the non-stationarity of the current signal under variable speed conditions and the difficulty of evaluating the operating state of the planetary gearbox under a tacholess condition, a three-phase current, variable-speed tacholess envelope order analysis method is proposed. Firstly, a tacholess rotation speed estimation is completed by extracting the trend term of the instantaneous frequency of the asynchronous motor's three-phase currents. The motor slip rate is assumed to be constant. Then, the envelope order analysis signal is obtained by re-sampling in the angular domain. Finally, the features of the envelope order signal are extracted, and a linear discriminant analysis (LDA) algorithm is used to fuse multiple indexes to generate a comprehensive feature reflecting the operating status of the planetary gearbox. The results of the simulation analysis and experimental verification show that the proposed method is effective in evaluating the operating state of the planetary gearbox under variable speed conditions. Compared with the traditional time-frequency ridge extraction method, the tacholess speed estimation method can improve the instantaneous speed estimation accuracy. The comprehensive index of envelope order completes the planetary gearbox state identification process, and a 95% classification accuracy rate is achieved.

7.
Front Neurosci ; 15: 716051, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34489633

RESUMO

The purpose of this study was to enhance the performance of steady-state visual evoked potential (SSVEP)-based visual acuity assessment with spatial filtering methods. Using the vertical sinusoidal gratings at six spatial frequency steps as the visual stimuli for 11 subjects, SSVEPs were recorded from six occipital electrodes (O1, Oz, O2, PO3, POz, and PO4). Ten commonly used training-free spatial filtering methods, i.e., native combination (single-electrode), bipolar combination, Laplacian combination, average combination, common average reference (CAR), minimum energy combination (MEC), maximum contrast combination (MCC), canonical correlation analysis (CCA), multivariate synchronization index (MSI), and partial least squares (PLS), were compared for multielectrode signals combination in SSVEP visual acuity assessment by statistical analyses, e.g., Bland-Altman analysis and repeated-measures ANOVA. The SSVEP signal characteristics corresponding to each spatial filtering method were compared, determining the chosen spatial filtering methods of CCA and MSI with a higher performance than the native combination for further signal processing. After the visual acuity threshold estimation criterion, the agreement between the subjective Freiburg Visual Acuity and Contrast Test (FrACT) and SSVEP visual acuity for the native combination (0.253 logMAR), CCA (0.202 logMAR), and MSI (0.208 logMAR) was all good, and the difference between FrACT and SSVEP visual acuity was also all acceptable for the native combination (-0.095 logMAR), CCA (0.039 logMAR), and MSI (-0.080 logMAR), where CCA-based SSVEP visual acuity had the best performance and the native combination had the worst. The study proved that the performance of SSVEP-based visual acuity can be enhanced by spatial filtering methods of CCA and MSI and also recommended CCA as the spatial filtering method for multielectrode signals combination in SSVEP visual acuity assessment.

8.
J Neural Eng ; 18(5)2021 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-34492637

RESUMO

Objective. Transient visual evoked potential (TVEP) can reflect the condition of the visual pathway and has been widely used in brain-computer interface. TVEP signals are typically obtained by averaging the time-locked brain responses across dozens or even hundreds of stimulations, in order to remove different kinds of interferences. However, this procedure increases the time needed to detect the brain status in realistic applications. Meanwhile, long repeated stimuli can vary the evoked potentials and discomfort the subjects. Therefore, a novel unsupervised framework was developed in this study to realize the fast extraction of single-channel TVEP signals with a high signal-to-noise ratio.Approach.Using the principle of nonlinear aperiodic FitzHugh-Nagumo (FHN) model, a fast extraction and signal restoration technology of TVEP waveform based on FHN stochastic resonance is proposed to achieve high-quality acquisition of signal features with less average times.Results:A synergistic effect produced by noise, aperiodic signal and nonlinear system can force the energy of noise to be transferred into TVEP and hence amplifying the useful P100 feature while suppressing multi-scale noise.Significance. Compared with the conventional average and average-singular spectrum analysis-independent component analysis(average-SSA-ICA) method, the average-FHN method has a shorter stimulation time which can greatly improve the comfort of patients in clinical TVEP detection and a better performance of TVEP waveform i.e. a higher accuracy of P100 latency. The FHN recovery method is not only highly correlated with the original signal, but also can better highlight the P100 amplitude, which has high clinical application value.


Assuntos
Potenciais Evocados Visuais , Vias Visuais , Humanos , Razão Sinal-Ruído
9.
J Neural Eng ; 18(5)2021 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-34571497

RESUMO

Objective.Motor imagery (MI), based on the theory of mirror neurons and neuroplasticity, can promote motor cortical activation in neurorehabilitation. The strategy of MI based on brain-computer interface (BCI) has been used in rehabilitation training and daily assistance for patients with hemiplegia in recent years. However, it is difficult to maintain the consistency and timeliness of receiving external stimulation to neural activation in most subjects owing to the high variability of electroencephalogram (EEG) representation across trials/subjects. Moreover, in practical application, MI-BCI cannot highly activate the motor cortex and provide stable interaction owing to the weakness of the EEG feature and lack of an effective mode of activation.Approach.In this study, a novel hybrid BCI paradigm based on MI and vestibular stimulation motor imagery (VSMI) was proposed to enhance the capability of feature response for MI. Twelve subjects participated in a group of controlled experiments containing VSMI and MI. Three indicators, namely, activation degree, timeliness, and classification accuracy, were adopted to evaluate the performance of the task.Main results.Vestibular stimulation could significantly strengthen the suppression ofαandßbands of contralateral brain regions during MI, that is, enhance the activation degree of the motor cortex (p< 0.01). Compared with MI, the timeliness of EEG feature-response achieved obvious improvements in VSMI experiments. Moreover, the averaged classification accuracy of VSMI and MI was 80.56% and 69.38%, respectively.Significance.The experimental results indicate that specific vestibular activity contributes to the oscillations of the motor cortex and has a positive effect on spontaneous imagery, which provides a novel MI paradigm and enables the preliminary exploration of sensorimotor integration of MI.


Assuntos
Interfaces Cérebro-Computador , Neurônios-Espelho , Eletroencefalografia , Humanos , Imagens, Psicoterapia , Imaginação
10.
J Neural Eng ; 18(5)2021 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-34592716

RESUMO

Objective. The steady-state visual evoked potential (SSVEP) is one of the most commonly used control signals for brain-computer interfaces (BCIs) due to its excellent interactive potential, such as high tolerance to noises and robust performance across users. In addition, it has a stable cycle, obvious characteristics and minimal training requirements. However, the SSVEP is extremely weak and companied with strong and multi-scale noise, resulting in a poor signal-to-noise ratio in practice. Common algorithms for classification are based on the principle of template matching and spatial filtering, which cannot obtain satisfied performance of SSVEP detection under the multi-scale noise. Therefore, using linear methods to extract SSVEP with obvious nonlinear and non-stationary characteristics, the useful signal will be attenuated or lost.Approach.To address this issue, two novel frameworks based on a two-dimensional nonlinear FitzHugh-Nagumo (FHN) neuron system are proposed to extract feature frequency of SSVEP.Results.In order to evaluate the effectiveness of the proposed methods, this research recruit 22 subjects to participate the experiment. Experimental results show that nonlinear FHN neuron model can force the energy of noise to be transferred into SSVEP and hence amplifying the amplitude of the target frequency. Compared with the traditional methods, the FHN and FHNCCA methods can achieve higher classification accuracy and faster processing speed, which effectively improves the information transmission rate of SSVEP-based BCI.


Assuntos
Interfaces Cérebro-Computador , Potenciais Evocados Visuais , Eletroencefalografia , Humanos , Neurônios , Estimulação Luminosa
11.
Front Cell Infect Microbiol ; 11: 711746, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34527602

RESUMO

Interstitial cystitis (IC) is a clinical syndrome characterized by frequency, urgency, and bladder pain or pelvic pain; however, the underlying pathophysiological mechanisms and diagnostic markers are unknown. In this study, microbiome and metabolome analysis were used to explain the urine signatures of IC patients. Urine samples from 20 IC patients and 22 control groups were analyzed by using 16S rRNA sequence and liquid chromatography coupled with mass spectrometry. Four opportunistic pathogen genera, including Serratia, Brevibacterium, Porphyromonas, and Citrobacter, were significantly upregulated in IC group. The altered metabolite signatures of the metabolome may be related to sphingosine metabolism, amino acid metabolism, and fatty acid biosynthesis. Meanwhile, the associations were observed between different metabolites and microbiomes of IC. The present study suggests that the combined signatures of IC in urine microbiome and metabolome may become its prospective diagnostic markers.


Assuntos
Cistite Intersticial , Microbiota , Biomarcadores , Humanos , Metaboloma , Estudos Prospectivos , RNA Ribossômico 16S/genética
12.
Trials ; 22(1): 504, 2021 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-34321056

RESUMO

BACKGROUND: Post-stroke depression (PSD) is a common complication after stroke which hinders functional recovery and return to social participation of stroke patients. Efficacy of conventional drug therapies for patients with PSD is still uncertain. Therefore, many patients prefer to use complementary and alternative therapies for PSD. Tuina (traditional Chinese manual manipulation) with herbal ointment is an integration of manual therapy, and ointment is an important part of traditional Chinese medicine (TCM) therapy. Preliminary experiments have shown that the Tuina with herbal ointment can improve the mental state of patients with PSD. The purpose of this study is to observe and verify the efficacy of Tuina combined with herbal ointment for patients with post-stroke depression, and to lay a foundation for further research on its mechanism of action. METHODS/DESIGN: In this study, a randomized controlled trial will be conducted in parallel, including two intervention groups: Tuina with herbal ointment group and herbal ointment for control group. A total of 84 eligible participants will be randomly assigned to the groups in a 1:1 ratio. All participants will receive conventional antidepressant venlafaxine treatment (75 mg QD), on which they received two different interventions. The interventions for both groups will be carried out 5 times each week for a period of 2 weeks. The primary outcome will be the Hamilton Rating Scale for Depression (HAMD). Secondary outcomes will include transcranial magnetic stimulation (TMS), as well as 36-item Short-Form Health Survey (SF-36) and Treatment Emergent Symptom Scale (TESS). They will be assessed at the baseline, at the end of the intervention (2 weeks), and during the 1 month and 3 months of follow-up by repeated measures analysis of variance. The significance level is 5%. Adverse events will be monitored at each visit to assess safety. All outcomes will be assessed and analyzed by researchers blinded to the treatment allocation. The purpose of this study will focus on observing the efficacy of Tuina with herbal ointment for patients with post-stroke depression, and to explore further the mechanisms of its effects. DISCUSSION: This study may evaluate clinical application value and safety of Tuina with herbal ointment in PSD patients, which can provide basis for clinical research and mechanism exploration of PSD. TRIAL REGISTRATION: Chinese Clinical Trial Registry ChiCTR2000033887 . Registered on 15 June 2020. DISSEMINATION: The results will be published in peer-reviewed journals and disseminated through the study's website and conferences.


Assuntos
Depressão , Acidente Vascular Cerebral , Antidepressivos , Depressão/diagnóstico , Depressão/tratamento farmacológico , Depressão/etiologia , Humanos , Medicina Tradicional Chinesa , Pomadas , Ensaios Clínicos Controlados Aleatórios como Assunto , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/diagnóstico , Resultado do Tratamento
13.
Artigo em Inglês | MEDLINE | ID: mdl-33872154

RESUMO

Brain computer interface (BCI) is a novel communication method that does not rely on the normal neural pathway between the brain and muscle of human. It can transform mental activities into relevant commands to control external equipment and establish direct communication pathway. Among different paradigms, steady-state visual evoked potential (SSVEP) is widely used due to its certain periodicity and stability of control. However, electroencephalogram (EEG) of SSVEP is extremely weak and companied with multi-scale and strong noise. Existing algorithms for classification are based on the principle of template matching and spatial filtering, which cannot obtain satisfied performance of feature extraction under the multi-scale noise. Especially for the subjects produce weak response for external stimuli in EEG representation, i.e., BCI-Illiteracy subject, traditional algorithms are difficult to recognize the internal patterns of brain. To address this issue, a novel method based on Chaos theory is proposed to extract feature of SSVEP. The rule of this method is applying the peculiarity of nonlinear dynamics system to detect feature of SSVEP by judging the state changes of chaotic systems after adding weak EEG. To evaluate the validity of proposed method, this research recruit 32 subjects to participate the experiment. All subjects are divided into two groups according to the preliminary classification accuracy (mean acc >70% or < 70%) by canonical correlation analysis and we define the accuracy above 70% as group A (normal subjects), below 70% as group B (BCI-Illiteracy). Then, the classification accuracy and information transmission rate of two groups are verified using Chaotic theory. Experimental results show that all classification methods using in our study achieve good performance for normal subjects while chaos obtain excellent performance and significant improvements than traditional methods for BCI-Illiteracy.


Assuntos
Interfaces Cérebro-Computador , Potenciais Evocados Visuais , Algoritmos , Eletroencefalografia , Humanos , Estimulação Luminosa , Tecnologia
14.
J Neural Eng ; 18(4)2021 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-33887707

RESUMO

Objective. This study aimed to explore an online, real-time, and precise method to assess steady-state visual evoked potential (SSVEP)-based visual acuity more rapidly and objectively with self-adaptive spatial frequency steps.Approach. Taking the vertical sinusoidal reversal gratings with different spatial frequencies and temporal frequencies as the visual stimuli, according to the psychometric function for visual acuity assessment, a self-adaptive procedure, the best parameter estimation by sequential testing algorithm, was used to calculate the spatial frequency sequence based on all the previous spatial frequencies and their significance of the SSVEP response. Simultaneously, the canonical correlation analysis (CCA) method with a signal-to-noise ratio (SNR) significance detection criterion was used to judge the significance of the SSVEP response.Main results.After 18 iterative trails, the spatial frequency to be presented converged to a value, which was exactly defined as the SSVEP visual acuity threshold. Our results indicated that this SSVEP acuity had a good agreement and correlation with subjective Freiburg Visual Acuity and Contrast Test acuity, and the test-retest repeatability was also good.Significance. The self-adaptive step SSVEP procedure combined with the CCA method and SNR significance detection criterion appears to be an alternative method in the real-time SSVEP acuity test to obtain objective visual acuity more rapidly and precisely.


Assuntos
Interfaces Cérebro-Computador , Potenciais Evocados Visuais , Eletroencefalografia , Estimulação Luminosa , Acuidade Visual
15.
Microorganisms ; 9(2)2021 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-33525426

RESUMO

Botrytis cinerea is a destructive necrotrophic pathogen that can infect many plant species. The control of gray mold mainly relies on the application of fungicides, and the fungicide fludioxonil is widely used in China. However, the field fungicide resistance of B. cinerea to this compound is largely unknown. In this study, B. cinerea isolates were collected from different districts of Shanghai province in 2015-2017, and their sensitivity to fludioxonil was determined. A total of 65 out of 187 field isolates (34.76%) were found to be resistant to fludioxonil, with 36 (19.25%) showing high resistance and 29 (15.51%) showing moderate resistance. Most of these resistant isolates also showed resistance to iprodione, and some developed resistance to fungicides of other modes of action. AtrB gene expression, an indicator of MDR1 and MDR1h phenotypes, was not dramatically increased in the tested resistant isolates. Biological characteristics and osmotic sensitivity investigations showed that the fitness of resistant isolates was lower than that of sensitive ones. To investigate the molecular resistance mechanisms of B. cinerea to fludioxonil, the Bos1 amino acid sequences were compared between resistant and sensitive isolates. Resistant isolates revealed either no amino acid variations or the mutations I365S, I365N, Q369P/N373S, and N373S.

16.
J Proteomics ; 238: 104137, 2021 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-33548507

RESUMO

Extracellular vesicles (EVs) are important for the transport of biomolecular materials and intercellular communication in eukaryotes. Recent research has revealed that they are involved in plant-pathogen interaction and pathogenesis of infected cells. Phytophthora capsici is a highly devastating oomycete pathogen with a broad host range. To increase infection and facilitate colonization, it secretes effector proteins during interaction with plants. In this study, we characterize for the first time the EVs from pathogen P. capsici through transmission electron microscopy. For the biological study of EVs, results showed that mixing high concentrations of EVs with zoospores could enhance the virulence of P. capsici. By sequencing the protein composition of EVs by liquid chromatography in tandem with mass spectrometry we found that there are many proteins related to metabolism, oxidation/reduction, and transport in EVs, indicating that they have important roles in pathogenesis and immunological processes within the host. SIGNIFICANCE: Extracellular vesicles (EVs) are important both at normal physiological processes as well as pathological progression during pathogen and host interaction. In this paper we first establish the extraction method of EVs from the important oomycete pathogen Phytophthora capsici. Bioinformatics analysis of EV proteomics revealed a variety of pathogenic-related proteins, like oxidation/reduction-related proteins, stress response proteins as well as elicitors. Our results will help better understanding the biological function of the EVs during plant and P. capsici interaction and providing the evidence for the role of EVs in pathogenesis of the P. capsici.


Assuntos
Vesículas Extracelulares , Phytophthora , Doenças das Plantas , Proteoma , Proteômica
17.
Nat Commun ; 12(1): 177, 2021 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-33420027

RESUMO

Glioblastoma (GBM) is the most common type of adult malignant brain tumor, but its molecular mechanisms are not well understood. In addition, the knowledge of the disease-associated expression and function of YTHDF2 remains very limited. Here, we show that YTHDF2 overexpression clinically correlates with poor glioma patient prognosis. EGFR that is constitutively activated in the majority of GBM causes YTHDF2 overexpression through the EGFR/SRC/ERK pathway. EGFR/SRC/ERK signaling phosphorylates YTHDF2 serine39 and threonine381, thereby stabilizes YTHDF2 protein. YTHDF2 is required for GBM cell proliferation, invasion, and tumorigenesis. YTHDF2 facilitates m6A-dependent mRNA decay of LXRA and HIVEP2, which impacts the glioma patient survival. YTHDF2 promotes tumorigenesis of GBM cells, largely through the downregulation of LXRα and HIVEP2. Furthermore, YTHDF2 inhibits LXRα-dependent cholesterol homeostasis in GBM cells. Together, our findings extend the landscape of EGFR downstream circuit, uncover the function of YTHDF2 in GBM tumorigenesis, and highlight an essential role of RNA m6A methylation in cholesterol homeostasis.


Assuntos
Neoplasias Encefálicas/metabolismo , Colesterol/metabolismo , Receptores ErbB/metabolismo , Glioblastoma/metabolismo , Proteínas de Ligação a RNA/metabolismo , Adulto , Animais , Neoplasias Encefálicas/genética , Linhagem Celular Tumoral , Proliferação de Células , Sobrevivência Celular , Transformação Celular Neoplásica/genética , Proteínas de Ligação a DNA/metabolismo , Receptores ErbB/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Glioblastoma/genética , Glioma , Humanos , Receptores X do Fígado/metabolismo , Sistema de Sinalização das MAP Quinases , Masculino , Camundongos , Fosforilação , Estabilidade de RNA , Proteínas de Ligação a RNA/genética , Transdução de Sinais , Fatores de Transcrição/metabolismo , Transcriptoma
19.
Int Ophthalmol ; 41(2): 587-598, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33044670

RESUMO

PURPOSE: Traditional color vision tests depend on subjective judgments and are not suitable for infant children and subjects with cognitive dysfunction. We aimed to explore an objective and quantitative color vision testing method based on sweep steady-state visual evoked potentials (sweep SSVEPs) and compare the results with subjective Farnsworth-Munsell (FM) 100-hue test results. METHODS: A red-green SSVEP pattern reversal checkboard paradigm at different luminance ratios was used to induce visual evoked potentials (VEPs) from 15 color vision deficiencies (CVDs) and 11 normal color vision subjects. After electroencephalography signals were processed by canonical correlation analysis, an equiluminance turning curve corresponding to the activation of the L-cones and M-cones at different levels of color vision was established. Then, we obtained different equiluminance T and proposed the SSVEP color vision severity index (ICVD) to quantify color vision function and the severity of CVDs. In addition, the FM 100-hue test was used to obtain subjective data for the diagnosis of color vision. RESULTS: The value of ICVD can be an indicator of the level of color vision. Both the total error scores (TES) and confusion index (C-index) of the FM 100-hue test were significantly correlated with ICVD values (P < 0.001, respectively). ICVD also had a good classification effect in detecting normals, anomalous trichromats and dichromats. Moreover, equiluminance T had a good effect on classifying protans and deutans in subjects with CVDs. CONCLUSION: Color vision evaluation with sweep SSVEPs showed a good correlation with subjective psychophysical methods. SSVEPs can be an objective and quantitative method to test color vision and diagnose CVDs.


Assuntos
Defeitos da Visão Cromática , Visão de Cores , Criança , Percepção de Cores , Testes de Percepção de Cores , Defeitos da Visão Cromática/diagnóstico , Potenciais Evocados Visuais , Humanos , Testes Visuais
20.
Neural Regen Res ; 16(7): 1229-1234, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33318399

RESUMO

Previous studies have shown that transcranial pulse current stimulation (tPCS) can increase cerebral neural plasticity and improve patients' locomotor function. However, the precise mechanisms underlying this effect remain unclear. In the present study, rat models of stroke established by occlusion of the right cerebral middle artery were subjected to tPCS, 20 minutes per day for 7 successive days. tPCS significantly reduced the Bederson score, increased the foot print area of the affected limbs, and reduced the standing time of affected limbs of rats with stroke compared with that before intervention. Immunofluorescence staining and western blot assay revealed that tPCS significantly increased the expression of microtubule-associated protein-2 and growth-associated protein-43 around the ischemic penumbra. This finding suggests that tPCS can improve the locomotor function of rats with stroke by regulating the expression of microtubule-associated protein-2 and growth-associated protein-43 around the ischemic penumbra. These findings may provide a new method for the clinical treatment of poststroke motor dysfunction and a theoretical basis for clinical application of tPCS. The study was approved by the Animal Use and Management Committee of Shanghai University of Traditional Chinese Medicine of China (approval No. PZSHUTCM190315003) on February 22, 2019.

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