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1.
Biomed Eng Online ; 23(1): 55, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38886737

RESUMO

BACKGROUND: Schizophrenia (SZ), a psychiatric disorder for which there is no precise diagnosis, has had a serious impact on the quality of human life and social activities for many years. Therefore, an advanced approach for accurate treatment is required. NEW METHOD: In this study, we provide a classification approach for SZ patients based on a spatial-temporal residual graph convolutional neural network (STRGCN). The model primarily collects spatial frequency features and temporal frequency features by spatial graph convolution and single-channel temporal convolution, respectively, and blends them both for the classification learning, in contrast to traditional approaches that only evaluate temporal frequency information in EEG and disregard spatial frequency features across brain regions. RESULTS: We conducted extensive experiments on the publicly available dataset Zenodo and our own collected dataset. The classification accuracy of the two datasets on our proposed method reached 96.32% and 85.44%, respectively. In the experiment, the dataset using delta has the best classification performance in the sub-bands. COMPARISON WITH EXISTING METHODS: Other methods mainly rely on deep learning models dominated by convolutional neural networks and long and short time memory networks, lacking exploration of the functional connections between channels. In contrast, the present method can treat the EEG signal as a graph and integrate and analyze the temporal frequency and spatial frequency features in the EEG signal. CONCLUSION: We provide an approach to not only performs better than other classic machine learning and deep learning algorithms on the dataset we used in diagnosing schizophrenia, but also understand the effects of schizophrenia on brain network features.


Assuntos
Eletroencefalografia , Redes Neurais de Computação , Esquizofrenia , Esquizofrenia/diagnóstico , Esquizofrenia/fisiopatologia , Humanos , Eletroencefalografia/métodos , Processamento de Sinais Assistido por Computador , Automação , Diagnóstico por Computador/métodos , Análise Espaço-Temporal
2.
Brain Res ; 1831: 148816, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38387716

RESUMO

The cognitive impairment in schizophrenia (SZ) is characterized by significant deficits in working memory task. In order to explore the brain changes of SZ during a working memory task, we performed time-domain and time-frequency analysis of event related potentials (ERP) of SZ during a 0-back task. The P3 wave amplitude was found to be significantly lower in SZ patients than in healthy controls (HC) (p < 0.05). The power in the θ and α bands was significantly enhanced in the SZ group 200 ms after stimulation, while the θ band was significantly enhanced and the ß band was weakened in the HC group. Furthermore, phase lag index (PLI) based brain functional connectivity maps showed differences in the connections between parietal and frontotemporal lobes between SZ and HC (p < 0.05). Due to the natural similarity between brain networks and graph data, and the fact that graph attention network can aggregate the features of adjacent nodes, it has more advantages in learning the features of brain regions. We propose a multi graph attention network model combined with adaptive initial residual (AIR) for SZ classification, which achieves an accuracy of 90.90 % and 78.57 % on an open dataset (Zenodo) and our 0-back dataset, respectively. Overall, the proposed methodology offers promising potential for understanding the brain functional connections of schizophrenia.


Assuntos
Memória de Curto Prazo , Esquizofrenia , Humanos , Memória de Curto Prazo/fisiologia , Encéfalo , Mapeamento Encefálico/métodos , Potenciais Evocados
3.
J Affect Disord ; 352: 1-9, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38355054

RESUMO

BACKGROUND: Psychological repurcussions of COVID-19 pandemic has received wide attention, but there's limited attention paid to psychological recovery afterwards. This study focuses on the changes and predictive factors of mental health of Chinese university students post-pandemic. METHODS: This study included 1175 Chinese undergraduate students sampled in May 2022 and May-June 2023, right before and after peaks of infections following the end of lockdown policy in China. The participants completed a survey of demographic variables, and three questionnaires: 12-item General Health Questionnaire, Positive Psychological Capital Questionnaire, and Prosocial Tendencies Measure. RESULTS: The participants sampled in 2023 have significant lower GHQ scores and higher PPQ scores than those sampled in 2022, while there is no significant difference in PTM scores between them. The proportion of participants with GHQ-12 scores exceeding 12 in 2023 showed slightly decrease compared to that in 2022. The infection of significant others, the sense of hope, and PPQ self-efficiency, hope and optimism subscale scores were significantly associated with GHQ-12 scores in 2023, but actual infection or quarantine experience were not. CONCLUSIONS: The mental health and psychological capital of the university students have been significantly improved within a year. It is worthy to pay attention to the infection of significant others, the sense of hope, and psychological capital in a pandemic to improve the mental health of university students. LIMITATIONS: Compared to a cross-sectional study, longitudinal research is the better choice for a two-year comparison.


Assuntos
COVID-19 , Humanos , COVID-19/prevenção & controle , COVID-19/psicologia , Saúde Mental , Pandemias , Estudos Transversais , Universidades , Controle de Doenças Transmissíveis , Estudantes/psicologia
4.
J Hazard Mater ; 467: 133763, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38359757

RESUMO

Practical gas sensing application requires sensors to quantify target analytes with high sensitivity and reproducibility. However, conventional surface enhanced Raman scattering (SERS) sensor lacks reproducibility and quantification arising from variations of "hot spot" distribution and measurement conditions. Here, a ratio-dependent SERS sensor was developed for quantitative label-free gas sensing. Au@Ag-Au nanoparticles (NPs) were filtered onto anodic aluminum oxide (AAO) forming Au@Ag-Au@AAO SERS substrate. 4-MBA was encapsulated in the gap of Au@Ag-Au and served as the internal standard (IS) to calibrate SERS signal fluctuation for improved quantification ability. Combined with headspace sampling method, SO2 residue in traditional Chinese medicine (TCM) can be extracted and captured on the immediate vicinity of Au@Ag-Au surface. The intensity ratio I613 cm-1/I1078 cm-1 showed excellent linearity within the range of 0.5 mg/kg-500 mg/kg, demonstrating superior quantification performance for SO2 detection. Signals for concentration as low as 0.05 mg/kg of SO2 could be effectively collected, much lower than the strictest limit 10 mg/kg in Chinese Pharmacopoeia. Combined with a handheld Raman spectrometer, handy and quantitative TCM quality evaluation in aspect of SO2 residue was realized. This ratiometric SERS sensor functioned well in rapid on-site SO2 quantification, exhibiting excellent sensitivity and simple operability.


Assuntos
Nanopartículas Metálicas , Nanopartículas Metálicas/química , Ouro/química , Reprodutibilidade dos Testes , Prata/química , Medicina Tradicional Chinesa
5.
BMC Infect Dis ; 23(1): 462, 2023 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-37430239

RESUMO

BACKGROUND: B7-H3 is an important immune checkpoint molecule that plays a negative role in immune regulation. This study was aimed to explore B7-H3 expression in HIV-infected patients and its clinical significance. METHODS: To explore the expression and clinical significance of B7-H3 in HIV-infected patients, we investigated the B7-H3 expression pattern and the correlation of B7-H3 expression with clinical parameters of HIV-infected patients with different levels of CD4+ T cells. To assess the role of B7-H3 in regulating the function of T cells in HIV infection, we performed a proliferation assay and T cell function test in vitro. RESULTS: B7-H3 expression in HIV-infected patients was significantly higher than that in healthy controls. mB7-H3 expression on CD4+CD25high T cells and CD14+ monocytes increased with disease progression. mB7-H3 expression on CD4+CD25high T cells and monocytes was negatively correlated with lymphocyte count, CD4+T cell count, and positively correlated with HIV viral load in HIV-infected patients. when the number of CD4+ T cells in HIV-infected patients was ≥ 200/µL, sB7-H3 and mB7-H3 expression levels on CD4+CD25high T cells and monocytes were negatively correlated with lymphocyte count, CD4+T cell count. sB7-H3 and mB7-H3 expression on monocytes were positively correlated with HIV viral load. B7-H3 inhibited the proliferation of lymphocytes and the secretion of IFN-γ in vitro, especially the ability of CD8+ T cells to secrete IFN-γ. CONCLUSIONS: B7-H3 played an important negative regulatory role in anti-HIV infection immunity. It could be used as a potential biomarker for the progression of HIV infection and a novel target for the treatment of HIV infection.


Assuntos
Linfócitos T CD8-Positivos , Infecções por HIV , Humanos , Relevância Clínica , Monócitos , Plasma , Bioensaio , Fatores de Transcrição
6.
Front Hum Neurosci ; 16: 799881, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35355584

RESUMO

To explore the change of brain connectivity in schizophrenics (SCZ), the resting-state EEG source functional connections of SCZ and healthy control (HC) were investigated in this paper. Different band single-layer networks, multilayer networks, and improved multilayer networks were constructed and their topological attributes were extracted. The topological attributes of SCZ and HC were automatically distinguished using ensemble learning methods called Ensemble Learning based on Trees and Soft voting method, and the effectiveness of different network construction methods was compared based on the classification accuracy. The results showed that the classification accuracy was 89.38% for α band network, 82.5% for multilayer network, and 86.88% for improved multilayer network. Comparing patients with SCZ to those with Alzheimer's disease (AD), the classification accuracy of improved multilayer network was the highest, which was 88.12%. The power spectrum in the α band of SCZ was significantly lower than HC, whereas there was no significant difference between SCZ and AD. This indicated that the improved multilayer network can effectively distinguish SCZ and other groups not only when their power spectrum was significantly different. The results also suggested that the improved multilayer topological attributes were regarded as biological markers in the clinical diagnosis of patients with schizophrenia and even other mental disorders.

7.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 30(1): 237-243, 2022 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-35123634

RESUMO

OBJECTIVE: To investigate the role of relationship between the expression of miRNA181a-5p and imbalance of Treg/Th17 in the pathogenesis of primary immune thrombocytopenia(ITP), which contributes to clarify the mechanism of T cell immune imbalance in ITP patients. METHODS: Peripheral blood was collected from 37 ITP patients, concluding 21 untreated patients and 16 effectively treated patients, and 19 healthy controls; Peripheral blood mononuclear cells (PBMC) were isolated and the expression of miRNA181a-5p and Notch1 was analyzed by RT-PCR. The proportion of Th17 subsets and Treg cells in the peripheral circulation was detected by flow cytometer (FCM). Clinical data of ITP group was collected, including age, platelet count and disease course. RESULTS: The expression of miR-181a-5p was significantly decreased in ITP group than that of healthy control group (P<0.01). After effective treatment, the expression of miR-181a-5p was significantly higher than that of ITP group (P<0.05), but still significantly lower than that of healthy control group (P<0.01); The expression of Notch1 was significantly increased in ITP group and effectively treated group than that of healthy control group (P<0.01). There was no significant difference in proportion of Treg cells in ITP group, effectively treated group and healthy control group (P>0.05). The proportion of Th17 subsets in ITP group was significantly increased than that of healthy control group (P<0.05), while the ratio of Treg/Th17 was significantly decreased (P<0.05). There was a positive correlation between the expression of miR-181a-5p and ratio of Treg/Th17 in ITP group (r=0.555). CONCLUSION: The expression of miR-181a-5p is significantly decreased in ITP patients, which is closely related to the imbalance of Treg/Th17 cells. After effective treatment, the expression of miR-181a-5p can be significantly corrected, but still failed to reach the level of healthy people. While the expression of Notch1 is significantly increased in ITP patients, and could not reach the level of healthy people after effective treatment.


Assuntos
Púrpura Trombocitopênica Idiopática , Linfócitos T Reguladores , Humanos , Leucócitos Mononucleares , Contagem de Plaquetas , Células Th17
8.
JID Innov ; 1(3): 100038, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34909734

RESUMO

Acupuncture treatment is based on acupoint stimulation; however, the biological basis is not understood. We stimulated one acupoint with catgut embedding for 8 weeks and then used isobaric tags for relative and absolute quantitation to screen proteins with altered expression in adjacent acupoints of Sprague Dawley rats. We found that kininogen expression was significantly upregulated in the stimulated and the nonstimulated adjacent acupoints along the same meridian. The enhanced kininogen expression was meridian dependent and was most apparent among small vessels in the subcutaneous layer. Enhanced signals of nitric oxide synthases, cGMP-dependent protein kinase, and myosin light chain were also observed at the nonstimulated adjacent acupoints along the same meridian. These findings uncover biological changes at acupoints and suggest the critical role of the kininogen-nitric oxide signaling pathway in acupoint activation.

9.
J Nanosci Nanotechnol ; 21(5): 3107-3114, 2021 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-33653486

RESUMO

We firstly discover the enhanced catalytic activity of magnetic noble metal nanoparticles mediated by surface plasmon resonance. Under light irradiation with certain wavelength, the catalytic performance of magnetic noble metal nanoparticles shows changes with different degrees and directions that are associated with the surface plasmon resonance (SPR) of the noble metal. Moreover, the coupling of silver and gold allows the catalytic performance of magnetic bimetallic Ag-Au nanoparticles to show more positive response to surface plasmon resonance. The magnetic bimetallic Ag-Au nanoparticles show excellent catalytic performance toward the reduction reaction of aromatic nitro group, and corresponding rate constant of the catalytic reduction reaction increases about three times with light irradiation.

10.
J Nanosci Nanotechnol ; 20(4): 2231-2238, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-31492232

RESUMO

In this paper, we report a novel kind of pH-mediated homogeneous magnetic Ag@Fe3O4 nanoparticles prepared by facile one-pot synthesis. The nanostructure and surface element composition along with magnetism of the as-synthesized hybrid nanoparticles can be easily adjusted by pH value in synthetic process. Furthermore, XRD and XPS detections indicated that the two components in the nanoparticles are both independent and certain synergistic. Compared with magnetic silver nanoparticles prepared by traditional multi-step methods, the homogeneous Ag@Fe3O4 nanoparticles showed excellent monodispersity and stability. Moreover, corresponding formation mechanism of the homogeneous hybrid magnetic nanoparticles was demonstrated in detail. Catalytic application of the homogeneous hybrid nanoparticles prepared under different pH values also verified rationality of the formation mechanism from side. This research provides a general strategy for constructing and large-scale preparing homogeneous magnetic hybrid metal nanoparticles.

11.
J Biochem Mol Toxicol ; 33(8): e22346, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31291034

RESUMO

Non-small-cell lung cancer (NSCLC) is one of the most prevalent type of lung cancers with an increased mortality rate in both developed and developing countries worldwide. Dieckol is one such polyphenolic drug extracted from brown algae which has proven antioxidant and anti-inflammatory properties. In the present study, we evaluated the anticancer property of dieckol against NSCLC cell line A549. The LC50 value of dieckol was found to be 25 µg/mL by performing 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and the antiapoptotic property of dieckol was analyzed by dual staining technique with acridine orange/propidium iodide (AO/PI) stains. It was further confirmed with flow cytometry analysis with Annexin FITC and JC-1 staining and the anti-invasive property was assessed by Transwell assay. The molecular mechanism of dieckol anticancer activity was confirmed by estimating the levels of caspases and by estimating the signaling proteins of Pi3K/AKT/mTOR signaling pathway using the immunoblotting technique. Our data suggest that dieckol is potent anticancer agent, it effectively inhibits the invasive and migratory property A549 cells and it also induces apoptosis via inhibiting Pi3K/AKT/mTOR signaling, activating the tumor suppressor protein E-cadherin signifying that dieckol is potent natural anticancer drug to treat NSCLC.


Assuntos
Benzofuranos/farmacologia , Carcinoma Pulmonar de Células não Pequenas/patologia , Proliferação de Células/efeitos dos fármacos , Neoplasias Pulmonares/patologia , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Carcinoma Pulmonar de Células não Pequenas/enzimologia , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Humanos , Neoplasias Pulmonares/enzimologia , Neoplasias Pulmonares/metabolismo
12.
Ecol Evol ; 9(13): 7480-7496, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31346417

RESUMO

Although the Masson pine moth, Dendrolimus punctatus, is one of the most destructive forest pest insects and is an endemic condition in China, we still do not fully understand the patterns of how its distribution range varies in response to Quaternary climatic oscillations. Here, we sequenced one maternally inherited mitochondrial gene (COI) and biparentally inherited nuclear data (ITS1 and ITS2) among 23 natural populations across the entire range of the species in China. A total of 51 mitotypes and 38 ribotypes were separately obtained using mtDNA and ITS1 data. Furthermore, significant phylogeographical structure (N ST > G ST, p < 0.01) were detected. The spatial distribution of mitotypes implied that two distinct groups existed in the species: one in the southwest distribution, including 10 locations, and the other located in the northeast region of China. It is suggested, therefore, that each group was derived from ancestors that occupied different isolated refugia during previous periods, possibly last glacial maximum. Mismatch distribution and Bayesian population dynamics analysis suggested the population size underwent sudden expansion, which is consistent with the results of ecological niche modeling. As a typical phytophagous insect, the history of population expansion was in accordance with the host plants, providing abundant food resources and habitat. Intraspecific success rate of barcoding identification was lower than interspecific ones, indicating a level of difficulty in barcoding individuals from different populations. However, it still provides an early insight into the pattern of genetic diversity within a species. OPEN RESEARCH BADGES: This article has been awarded an Open Data and Open Materials. All materials and data are publicly accessible via the Open Science Framework at https://doi.org/10.5061/dryad.2df87g2. Learn more about the Open Practices badges from the Center for Open Science: https://osf.io/tvyxz/wiki.

13.
Front Mol Neurosci ; 11: 343, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30319352

RESUMO

Osteoblasts derived osteocalcin (OCN) is recently reported to be involved in dopaminergic neuronal development. As dopaminergic neuronal injury in the substantia nigra (SN) is a pathological hallmark of Parkinson's disease (PD), we investigated whether OCN could exert protective effects on 6-hydroxydopamine (6-OHDA)-induced PD rat model. Our data showed that the OCN level in the cerebrospinal fluid (CSF) in PD rat models was significantly lower than that in controls. Intervention with OCN could improve the behavioral dysfunction in PD rat models and reduce the tyrosine hydroxylase (TH) loss in the nigrostriatal system. In addition, OCN could inhibit the astrocyte and microglia proliferation in the SN of PD rats. In vitro studies showed that OCN significantly ameliorated the neurotoxicity of 6-OHDA through the AKT/GSK3ß signaling pathway. In summary, OCN plays a protective role against parkinsonian neurodegeneration in the PD rat model, suggesting a potential therapeutic use of OCN in PD.

14.
J Nanosci Nanotechnol ; 18(12): 8201-8206, 2018 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-30189938

RESUMO

In this paper, we first report the selective reduction of nitro group in aryl halides catalyzed by silver nanoparticles modified with ß-CD. Taking advantage of hydrophobic lumen and donor-acceptor behavior of ß-CD, the halogenated alkyl groups on the aromatic ring can be enveloped in the inner cavity that thereby inhibits the reduction of the halogen. For validating the mechanism proposed by us, different silver nanoparticles were applied in parallel experiments. In our experiments, UV-vis spectra and NMR spectra were used to characterize the selectivity. This strategy represents an outstanding improvement on the synthesis of halogenated aromatic amines in comparison with the traditional route, and greatly expands the application of silver nanoparticles in catalytic field.

15.
J Proteomics ; 185: 8-24, 2018 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-30003963

RESUMO

Lysine acetylation is a widespread protein posttranslational modification in all organisms. However, quantitative acetylproteome characterization in response to water deficit during crop grain development remains unknown. In the study, we performed the first large-scale acetylproteome analysis of developing wheat grains under water-deficit using label-free quantitative proteome approach. In total, 716 acetylated sites corresponding to 442 acetylated proteins were identified, of which 106 acetylated sites representing 93 acetylated proteins (including 88 non-histones) showed significant changes under water-deficit. The functional classification showed that 57% and 20% of acetylated proteins were related to metabolic and cellular processes, respectively. Water-deficit caused widespread functional crosstalk between protein acetylation and other PTMs. Particularly, both acetylation and phosphorylation occurred in two key enzymes involved in starch biosynthesis, sucrose synthase (SuSy) and ADP glucose pyrophosphorylase (AGPase). Their crosstalk could play important roles in starch biosynthesis and yield formation under drought conditions. Western blot analysis combined with tandem mass spectrometry identification further verified the reliability of the acetylproteome results. Most of the acetylated proteins showed consistences between transcription and post-translation levels by quantitative real-time PCR. A putative metabolic pathway was proposed to dissect the roles of protein acetylation in regulation of drought response and defense during wheat grain development. SIGNIFICANCE: Lysine acetylation is a widespread modification in all organisms. We performed the first large-scale acetylproteome analysis of developing wheat grains under water-deficit and revealed key acetylated proteins involved in wheat grain development and starch biosynthesis.


Assuntos
Acetiltransferases/metabolismo , Lisina/metabolismo , Processamento de Proteína Pós-Traducional , Proteoma/análise , Amido/biossíntese , Triticum , Acetilação , Grão Comestível/crescimento & desenvolvimento , Grão Comestível/metabolismo , Proteínas de Plantas/análise , Proteínas de Plantas/metabolismo , Proteoma/metabolismo , Proteômica/métodos , Amido/metabolismo , Espectrometria de Massas em Tandem , Triticum/crescimento & desenvolvimento , Triticum/metabolismo
16.
Sci Rep ; 7(1): 7321, 2017 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-28779137

RESUMO

The pathophysiologic mechanisms of epileptogenesis are poorly understood, and no effective therapy exists for suppressing epileptogenesis. Numerous reports have shown that nicotinamide adenine dinucleotide (NAD+) has neuroprotective effects, suggesting its potential use for treating epileptogenesis. Here we evaluated the effects of NAD+ on epileptogenesis and the mechanisms underlying these effects. In pilocarpine-induced status epilepticus (SE) model mice, NAD+ was injected three times within 24.5 h after SE. NAD+ intervention significantly reduced the incidence of spontaneous recurrent seizure (SRS) and abnormal electroencephalogram (EEG) activity, rescued contextual fear memory formation, reduced neuronal loss in the CA1 region of the hippocampus at SRS stage. Furthermore, exogenous supply of NAD+ distinctly reversed the seizure-induced depletion of endogenous NAD+, reduced neuronal apoptosis in the CA1 region of the hippocampus, and reversed the augmented Acp53/p53 ratio at the early stage of epileptogenesis. Our findings demonstrated that early-stage intervention with NAD+ prevents epileptogenesis in pilocarpine-induced SE mice by suppressing neuronal apoptosis.


Assuntos
Anticonvulsivantes/metabolismo , Epilepsia/etiologia , Epilepsia/metabolismo , NAD/metabolismo , Animais , Anticonvulsivantes/farmacologia , Apoptose/efeitos dos fármacos , Ondas Encefálicas , Região CA1 Hipocampal/metabolismo , Região CA1 Hipocampal/patologia , Contagem de Células , Modelos Animais de Doenças , Eletroencefalografia , Epilepsia/diagnóstico , Epilepsia/tratamento farmacológico , Incidência , Masculino , Memória , Camundongos , NAD/farmacologia , Células Piramidais/metabolismo , Células Piramidais/patologia , Índice de Gravidade de Doença
17.
Sci Rep ; 7(1): 3045, 2017 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-28596523

RESUMO

In the adult mouse hippocampus, NMDA receptors (NMDARs) of CA1 neurons play an important role in the synaptic plasticity. The location of NMDARs can determine their roles in the induction of long-term potentiation (LTP). However, the extrasynaptic NMDARs (ES-NMDARs) dependent LTP haven't been reported. Here, through the use of a 5-Hz stimulation and MK-801 (an irreversible antagonist of NMDARs) in the CA1 neurons of adult mice hippocampal slices, synaptic NMDARs were selectively inhibited and NMDAR-mediated excitatory postsynaptic currents were not recovered. We found that a robust LTP was induced by 3-train 100-Hz stimulation when the synaptic NMDARs and extrasynaptic NR2B containing NMDARs were blocked, but not in the any of the following conditions: blocking of all NMDARs (synaptic and extrasynaptic), blocking of the synaptic NMDARs, and blocking of the synaptic NMDARs and extrasynaptic NR2A-containing NMDARs. The results indicate that this LTP is ES-NMDARs dependent, and NR2B-containing ES-NMDARs modulates the threshold of LTP induction.


Assuntos
Região CA1 Hipocampal/metabolismo , Potenciação de Longa Duração , Células Piramidais/metabolismo , Receptores de N-Metil-D-Aspartato/metabolismo , Animais , Região CA1 Hipocampal/citologia , Região CA1 Hipocampal/fisiologia , Maleato de Dizocilpina/farmacologia , Antagonistas de Aminoácidos Excitatórios/farmacologia , Potenciais Pós-Sinápticos Excitadores , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Células Piramidais/fisiologia , Receptores de N-Metil-D-Aspartato/antagonistas & inibidores
18.
Front Plant Sci ; 7: 1567, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27812362

RESUMO

Oxidative stress in plants can be triggered by many environmental stress factors, such as drought and salinity. Brachypodium distachyon is a model organism for the study of biofuel plants and crops, such as wheat. Although recent studies have found many oxidative stress response-related proteins, the mechanism of microRNA (miRNA)-mediated oxidative stress response is still unclear. Using next generation high-throughput sequencing technology, the small RNAs were sequenced from the model plant B. distachyon 21 (Bd21) under H2O2 stress and normal growth conditions. In total, 144 known B. distachyon miRNAs and 221 potential new miRNAs were identified. Further analysis of potential new miRNAs suggested that 36 could be clustered into known miRNA families, while the remaining 185 were identified as B. distachyon-specific new miRNAs. Differential analysis of miRNAs from the normal and H2O2 stress libraries identified 31 known and 30 new H2O2 stress responsive miRNAs. The expression patterns of seven representative miRNAs were verified by reverse transcription quantitative polymerase chain reaction (RT-qPCR) analysis, which produced results consistent with those of the deep sequencing method. Moreover, we also performed RT-qPCR analysis to verify the expression levels of 13 target genes and the cleavage site of 5 target genes by known or novel miRNAs were validated experimentally by 5' RACE. Additionally, a miRNA-mediated gene regulatory network for H2O2 stress response was constructed. Our study identifies a set of H2O2-responsive miRNAs and their target genes and reveals the mechanism of oxidative stress response and defense at the post-transcriptional regulatory level.

19.
Sci Rep ; 6: 26268, 2016 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-27199260

RESUMO

Potential distributions of endemic relic shrubs in western Ordos were poorly mapped, which hindered our implementation of proper conservation. Here we investigated the applicability of ecological niche modeling for endangered relic shrubs to detect areas of priority for biodiversity conservation and analyze differences in ecological niche spaces used by relic shrubs. We applied ordination and niche modeling techniques to assess main environmental drivers of five endemic relic shrubs in western Ordos, namely, Ammopiptanthus mongolicus, Amygdalus mongolica, Helianthemum songaricum, Potaninia mongolica, and Tetraena mongolica. We calculated niche overlap metrics in gridded environmental spaces and compared geographical projections of ecological niches to determine similarities and differences of niches occupied by relic shrubs. All studied taxa presented different responses to environmental factors, which resulted in a unique combination of niche conditions. Precipitation availability and soil quality characteristics play important roles in the distributions of most shrubs. Each relic shrub is constrained by a unique set of environmental conditions, the distribution of one species cannot be implied by the distribution of another, highlighting the inadequacy of one-fits-all type of conservation measure. Our stacked habitat suitability maps revealed regions around Yellow River, which are highly suitable for most species, thereby providing high conservation value.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Magnoliopsida/fisiologia , China , Espécies em Perigo de Extinção , Geografia , Chuva , Solo
20.
Sci Rep ; 6: 23086, 2016 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-27052791

RESUMO

There is growing interest in engineering nerve cells in vitro to control architecture and connectivity of cultured neuronal networks or to build neuronal networks with predictable computational function. Pattern technologies, such as micro-contact printing, have been developed to design ordered neuronal networks. However, electrophysiological characteristics of the single patterned neuron haven't been reported. Here, micro-contact printing, using polyolefine polymer (POP) stamps with high resolution, was employed to grow cortical neurons in a designed structure. The results demonstrated that the morphology of patterned neurons was well constrained, and the number of dendrites was decreased to be about 2. Our electrophysiological results showed that alterations of dendritic morphology affected firing patterns of neurons and neural excitability. When stimulated by current, though both patterned and un-patterned neurons presented regular spiking, the dynamics and strength of the response were different. The un-patterned neurons exhibited a monotonically increasing firing frequency in response to injected current, while the patterned neurons first exhibited frequency increase and then a slow decrease. Our findings indicate that the decrease in dendritic complexity of cortical neurons will influence their electrophysiological characteristics and alter their information processing activity, which could be considered when designing neuronal circuitries.


Assuntos
Córtex Cerebral/fisiologia , Fenômenos Eletrofisiológicos , Neurônios/fisiologia , Potenciais de Ação , Animais , Proliferação de Células , Sobrevivência Celular , Células Cultivadas , Córtex Cerebral/citologia , Dendritos/fisiologia , Modelos Neurológicos , Neurônios/citologia , Ratos
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